IFR Flying in Europe

The purpose of this article, originally written in 2005, is to help anyone who has, or is training for, an IR and who is unfamiliar with IFR flight planning procedures in Europe. Later, the information was expanded following requests from other pilots. The weather section should be well known to anyone with an IR but was requested for a magazine article. Revisions were done in 2007 to take out a lot of detail which was no longer applicable.

The article is written from the perspective of a UK single-engine non-pressurised pilot limited to say FL200. The writer is a UK PPL/NIGHT/IMC and FAA CPL/IR with 900 hours, mostly in a Socata TB20.

It's difficult to get this info together. Fresh JAA IR holders have usually trained between a very limited number of airports in the UK. Seeking the advice of a working airline pilot is productive but only up to a point because the route planning and flight plan filing is done by a separate ground team. Also, the internet has very recently made the process a lot more streamlined.

FAA IR holders who trained in the USA have an additional hurdle to cross because the U.S. system is different and a lot simpler (one can plan an airways route from the chart alone, and usually one can fly it as filed). The U.S. airspace rules can be very different from the European ones although they are closer on IFR procedures. FAA IFR clearances are different too. The FAA IR pilot flying an N-reg aircraft must comply with FAA rules but also any local rules of the air: CAA, JAA, ICAO - the whole lot.

Required Equipment

Certain minimum equipment must be carried on the aircraft. Contrary to popular belief among pilots there is little or no regulation prescribing equipment to be used. Usage is not the same as carriage! For example, many UK private pilots believe that GPS usage is illegal, which is rubbish.

The equipment that needs to be carried varies from one country to the next, and of course varies according to the class of airspace, and the full matrix would be so complicated that a pilot would tear all his hair out and never fly again.

The UK Air Navigation Order, the latest (2005) version, is here. Look in Schedule 4 and Schedule 5. There have been some recent amendments concerning the carriage and use of oxygen, for example, but these apply only to G-reg aircraft; oxygen use in an N-reg is governed by the well known FAA rules.

GPS: The UK ANO is silent on GPS. However, above FL095 in general one needs a BRNAV (basic area navigation) approved navigation means - this applies all over Europe. In the GA context the only useful way to meet this requirement is a BRNAV approved GPS (one other way is a BRNAV approved KNS80 with antenna filters, but that won't be any good if out of the coverage of a VOR/DME). The common FAA/IFR-approved units such as GNS430/530 and KLN90/KLN94 are OK if the GPS supplement in the aircraft operating manual authorises their use for IFR navigation. Owners of N-reg aeroplanes who fly GPS approaches in the USA will likely have a suitable supplement in their operating manual but merely fitting e.g. a GNS530 will not result in an installation legal for this purpose. It's very difficult to find references for this stuff - the whole area of European certification is now run by EASA.

ADF, DME: The UK Air Navigation Order requires an ADF for IFR in controlled airspace - clearly pointless. A quick look at some other AIPs at the Eurocontrol EAD website suggests this is not common although Sweden requires not just an ADF but also, like the USA, an ELT transmitting on 121.5 and the soon to be defunct 243MHz. The equipment list for each country is in the country's AIP GEN 1.5 and for Switzerland it returns the interesting result that a BRNAV GPS removes the need for an ADF for all IFR flight (ADF is still explicitly required for approaches containing NDBs, as one might expect). Germany requires an ADF only for approaches which use an NDB, which makes sense. France does not require an ADF. The trend for most of the "up and coming" European countries such as the Czech Rep is to not require an ADF. Most countries do however require a DME and - unlike in the USA - a GPS cannot be used instead of a DME. [Note 10/2007: the EAD links above are likely to be broken because the EAD website gets regularly changed around - you can find the current docs at the main site under "Pams Light"]

There is no central repository for this stuff that I am aware of; the EAD website (requires a password but registration is free) was supposed to become such a repository but evidently a number of countries (e.g. Greece) enjoy selling printed versions of their AIP too much... A separate list of national AIPs is here - many of these also appear at the EAD site, and not necessarily with identical data!!

There is an interesting argument that a GPS qualifies as a "distance measuring equipment" if the requirement is thus worded. Since all these regulations specify equipment to be carried but don't specify equipment to be used, there is a further possible argument that any means of navigation (and, therefore, a GPS of any sort) can be used to fly NDB approaches especially outside controlled airspace, if the requirement for an ADF is limited to controlled airspace. It would be interesting to find out whether any of the national aviation authorities have obtained legal advice on this. If they have, and the result was what I think it was, they would not be publicising it... Despite persistent rumours, there is no evidence that ADF+DME carriage has ever been enforced. The most commonly highlighted scenario is the Cirrus SR20/22 which have been sold in significant numbers in Europe with an IFR GPS but without ADF or DME.

If the aircraft is not G-registered then it must also carry any equipment mandated by its state of registry so e.g. if it is N-reg it needs to carry an ELT.

PRNAV is the big shadow on the mandatory-equipment horizon, not in terms of flying but in terms of wasting money on pointless avionics, but currently nobody knows what will happen and when. The requirements are being formulated in piecemeal fashion around the European CAAs (see JAA TGL10 for a start) and as usual they are being anally retentively interpreted by some authorities. Some notes on PRNAV are near the end of this article (under avionics upgrades). PRNAV could be a major issue if "PRNAV-mandatory" airspace came into existence but this is not currently on the horizon. It's much easier under FAA (N-reg) where a LoA (letter of authorisation) from the GPS manufacturer does the job, and the more modern GPSs come with one of these.

Do ATC care about your equipment?

It is up to the pilot to make sure he is legal for the route, airspace, etc. However, this leaves the question: do ATC look at the equipment declared in the flight plan and offer different routings? My enquiries suggest that in Europe the answer is NO. I got a very different answer for Australia though. However, the Eurocontrol computer has been reported to be rejecting any flight plan above FL195 which does not list 8.33 capability.

One would think that a flight plan above FL095 not listing BRNAV capability would get rejected, and similarly with Mode S in many airspaces. However, there is no evidence that ATC look at this at all - currently.

Route Planning

The first thing is to plan the route along the airways system. One can use the paper charts (Jeppesen or Aerad, etc). I think the Jepp charts are much better because the Aerad ones combine both upper and lower airways on the same chart and do it poorly. Or one can use IFR flight planning software like Jeppesen FliteStar IFR or, at a stretch, Navbox.

Many airways are bidirectional; others have a direction shown. On the Jeppesen charts, each has a minimum en-route altitude (MEA). So on the face of it it's easy:

The airways under discussion are highlighted in yellow.

Airway L604 runs on a track of 331 (degrees magnetic) from YNN (108.60) to TRN (117.70), and bidirectional. The airway MEA is FL110.

Airway G12 also runs between YNN and KRK, MEA is FL080, and is bidirectional. Airway M600 runs on the same route, MEA is also FL080 and is also bidirectional. The distance between these two waypoints is shown as 38nm.

Airway W62 is directional from RODON to GRIBA but continues as bidirectional from (apparently) GRIBA to KRK.

So one could just plan a route using the obvious selection of these airways. This works in the USA, where they do have preferred routes but those are not mandatory for flight plan filing purposes. Unfortunately planning a route straight off the chart won't usually work in Europe, because of additional factors:

a) Standard Route Documents (SRDs). Each country publishes a manual giving preferred and prohibited airways for various routes. These documents can be either free (online, like the UK one is) or you have to buy them

b) Conditional Routes (CDRs). On a lot of Jepp charts, some of the airways have a black '1', '2', or '3' after the designator. These are routes which are normally closed during the week but are open sometimes in the evenings, but more often than not during weekends / public holidays when the military aren't playing.

c) Temporary restrictions. These are just that. If e.g. there is a big airshow or military activity somewhere, then an airway might be closed.

Eurocontrol runs a database which contains all this and all FPs are verified against this database before acceptance. Obviously there is no way to plan a definitive route with any means that doesn't have access to the database.

The Job #1 is to get an FP accepted. It doesn't have to be exact since ATC will give you a series of direct-tos (or, in busy airspace, vectors) anyway along most of the route, so the route finally flown will always differ from anything planned.

IFR flight plans are filed via a Eurocontrol system called IFPS (Integrated Flight Plan Processing System) which distributes the flight plan to all enroute units, plus departure and destination, in seconds. This makes it possible to file a flight plan and depart minutes later - as soon as the tower confirms they have received it.

The IFPS operating manual, March 2007 version, is here local copy. This 504 page tome contains vastly more information than any pilot should ever need to know, but it looks like a useful reference.

In the following text, the words Eurocontrol and CFMU tend to get used interchangeably, and both refer to the anonymous computer is Brussells which manages the IFR routes.

How to design a valid route?

There are various ways to design a route which is accepted by Eurocontrol. Ideally, the route should verify with the Eurocontrol/CFMU route verification website before it is used in a flight plan. This website is routinely used to verify a route before it is used in a flight plan submission, but it isn't useful for generating a route, and the majority of its rejection messages are totally cryptic. About the only obvious ones are where some airway does not exist below a certain level - in that case you simply raise the level.

a) Get it right straight off the IFR chart

Just pick the airways, noting their directions and MEAs. This works in some parts of Europe (notably France) but is otherwise nearly useless due to all the additional restrictions.

b) Use the autorouting function in Flitestar

As with a) above, this works OK in some parts of Europe but in my experience most of its routings are still rejected by Eurocontrol, largely because Flitestar does not contain the SRDs and the CDRs.

c) Take a chance on it and enable Eurocontrol to do amendments

This involves using some means (any means) to generate a route which is more or less valid (taking into account airway directions and MEAs only) - for example using methods a) or b) above - and file the flight plan with this remark in Field 18

RMK/ IFPS REROUTE ACCEPTED

A lot of people have been doing this for years and think that this enables Eurocontrol to amend the route regardless. However, it occassionally does still result in a rejected flight plan, and then you are stuffed with no options left but to try some other route. My experience is that on occassions Eurocontrol will wash their hands of amending a route, and it is likely to happen at the least convenient time, because if you had time to play you would have worked out a good route in the first place!

This method obviously assumes that the pilot has a means of receiving the amended route, so he knows what he is supposed to be flying! With Homebriefing you have the option of an email and/or a GSM text message, but in virtually every case I have found that the text message arrives hours later. The email does appear to be transmitted immediately though, so you need a means of receiving emails during the period between filing the flight plan and getting into the aircraft. The airport tower will advise you of any allocated departure slots, but they may not realise your routing has been amended.

d) Use a website which has access to the route database.

Currently there is no official (and free) facility which can "autoroute". The Italian ASA site however gets very close. It seems to have the SRDs and CDRs, and the majority of the routes it generates do get through the Eurocontrol verification website straight away. Usually, you have to play with this one interactively, adding more and more of the restrictions that appear in the table at the bottom of the page, and eventually you should get something that gets through.

On many routes, this site will return a route for which no restrictions are reported in the above mentioned table, but which still fails the CFMU validation. In such cases, one has to manually exclude the offending airway sectionsby entering then in the restrictions box using the proper syntax e.g. A34(DRAKE>SITET).

The site claims to be for flight simulation use only and they talk about a commercial service which works fully but all emails I have sent them either bounce back or are ignored. Eventually I found a mailing address in Italy and wrote to them. I didn't get a reply. I even tried to pay up their paid-for service, only to get an incomprehensible page in Italian. I know someone eventually managed to contact them and pay for the commercial service, only to report that there is nothing much in there that's worth having over the free version. It's an embarrassing observation that the best currently available method - for private pilots - for generating European airways routes is an informal facility for people playing with flight simulators!

The chief limitation of the above Italian "ASA" site is that while it enables you to exclude routes, there is no way to specify "fly through" waypoints. One could do it indirectly by specifying a whole lot of exclusions, thus forcing the routing where you actually want to go, but it's clumsy. Again, Eurocontrol's internal tools (which they won't release to the outside) can do all that.

e) Use some tricks

It is obvious to anybody flying IFR that the route actually flown isn't, or doesn't need to be, exactly identical to that which was filed - either because ATC move you around or because you can ask them for shortcuts when airborne. Accordingly, pilots have developed a range of hacks which can be used to get a route accepted by Eurocontrol. This practice is perhaps questionable but frankly there isn't much of a choice. One can stuff any route into the CFMU validation website and if it says it's OK then it's OK to file a flight plan with it!!

Use variable levels. The ASA site will generate a route but bizzarely it won't specify the level at which you can successfully file it. Most of the time, one can get it accepted at a single level e.g. FL150, but sometimes one can get a more direct routing if one is prepared to file for different levels at different places. And there are instances where getting a route accepted is close to impossible without doing this. In the following example

G40 ARSIL A6 DJL SPR/N0150F190 TOP/N0150F110 M730 ANC/N0150F070 L612 BRD/N0150F110 TRL

you can see four self-explanatory level changes. Unfortunately one cannot specify just a level; the speed has to be specified at the same time, as shown. Flitestar's autoroute function often generates routings with such level changes. So, if you have a good route but the Eurocontrol validation site keeps chucking it out because one particular airway segment has to be flown below a certain level while another one further along as to be flown above that level (thus making it impossible to file a single-level flight plan on that route) this is the way to deal with it.

This technique just helps to get the flight plan into the system. With the exception of things like mountains or airway MEAs, ATC is almost certainly not going to care about the different levels and will let you fly the whole route at FL100 or whatever you ask for.

Use DCTs. These can be used to get routes where no suitable airways exist. In this case one must be careful with MEAs and breaching restricted/prohibited areas; the existing airway system is already designed to avoid the permanent ones. The CFMU website does not validate the MEA on DCT routes - this would require the software to have a terrain/obstacle map of the whole of Europe. As always, the pilot is responsible for terrain clearance! There is also a limit on the length of a DCT leg ; this can be anywhere from zero (i.e. this method cannot be used) in some airspaces, to 50nm in others. Some information on commonly permitted DCT legs is here. In the extreme, a sequence of DCTs can be used as a really dirty trick to bypass CFMU route checking.

Avoid named waypoints. The CFMU software does not error-check a route whose waypoints are specified using lat/long coordinates, or using the standard VOR-relative notation (e.g. MID240033 being the 240 radial from MID, 33D). Such waypoints merely need to be less than 50nm apart (or whatever the maximum permitted DCT leg is within the airspace in question). In some cases one can use the absurd reduction of this e.g. MID000000 DCT CPT000000 to avoid the computer thinking you are routing along an airway running MID-CPT and enforcing the airway MEA/direction.

The mysterious "GAT" keyword. The CFMU software does not check a route that contains the term "GAT" (Eurocontrol-speak for "general aviation traffic") anywhere within the route. The "GAT" can be at the beginning or at the end of the route, but it must be before an airways designator. If it is used after an airways designator, that airway is reported "unknown". This feature is really weird but appears to be intentional. I have not yet had to do this.

f) Use an airport handling agent, or another commercial service

These tend to be used by commercial/professional pilots.

There is also a product from a German company which seems to be very good, and combines in-flight radar etc data using a satellite downlink; the price however is very high.

g) Get Eurocontrol to help you

There are two contact numbers for Eurocontrol where somebody can help sort out problematic routings.

The numbers for the IFP1 and IFP2 help desks are: 0032 2 745 1950 and 0033 16 988 1750.

If your flight plan is getting rejected, or you would like to avoid certain routings (e.g. long over-water crossings, where there is an obvious alternative) just call them up, give them your callsign/reg and tell them what the problem is. They are reportedly very helpful. They also have the ability to force an unacceptable flight plan through the system manually. This might not always be possible, but may on occasion be your saving grace.

h) Use the standard route manuals

These have not been generally available online but have just (2008) been published here. This is a new development which I haven't tried yet. It offers the possibility of developing a route which passes through desired waypoints, e.g. to avoid large stretches of water.

i) Use software tools

Eurocontrol have in-house tools but have never released them to the public - reportedly because a certain commercial flight services provider complained it would ruin their business...

However, a new autorouting tool, Autoplan, has recently been developed which generates CFMU-validated routings in a minute or so. I have been using this and it has transformed the whole horrid IFR routing business. FlightPlanPro is another tool. Currently (2008) both of these are free.

Miscellaneous tips

Flying to/from airports with no SID/STAR. Often, when departing from or returning to the UK, the first or last part of the route lies outside controlled airspace (OCAS) and such airports do not usually have SIDs or STARs. The most official way to handle OCAS sections is to file them VFR (using a Y or Z flight plan) but this is largely unnecessary - a straight DCT from the airport to the terminating waypoint of the airways route usually works nowadays. The CFMU computer appears to insert an implicit DCT into flight plans anyway so e.g EGKA DRAKE ... will be assumed to be EGKA DCT DRAKE but sometimes several DCTs can be used to reach the start of the filed route.
Dirty tricks: some OCAS routes which are 100% legal are rejected by CFMU; for example if one specifies an airway whose MEA is inside CAS but you actually want to fly in Class G below it. In such a case, use the airway waypoints (with DCTs joining them up) but do not use the airway names. Or use the above mentioned lat/long or VOR-relative waypoint specifications if there are no usable waypoints. Sometimes one may have to use e.g. "MID000000" instead of "MID", to avoid the system deciding that you are flying an airway after all and then chucking out the route because you are below the airway's MEA..

STAR Limit Exceeded. This is a common and meaningless CFMU error message. It tends to be caused by the last section of the route, connecting to the destination, being longer than the maximum DCT leg length for that airspace. To get around this, insert additional waypoints to break it up a bit. If the airspace has a maximum DCT leg of zero, then you must connect to the start of a STAR (and all IFR airports in such an airspace should have published STARs) which rules out VFR-only airports as a filed destination, unless one changes to "VFR" for the last section (with a "Y" flight plan).

VFR-only airports For some countries (notably Spain and Germany) CFMU rejects "I" flight plans to/from an airport without IFR procedures, so you have to use Z or Y. Beware: as soon as IFR is cancelled formally by ATC, the whole predictable IFR apparatus washes its hands of you and you are thrown into the bad olde world of VRPs, reporting at some church tower, and all the other rubbish which you hoped to avoid after you got your IR!

Slots

These are departure delays generated by the Eurocontrol computer. If you have filed the flight plan via Homebriefing, you should get any slot notifications by email or SMS, otherwise the tower will tell you when you are about to depart...

Slots are relatively rare, and have a habit of being cancelled (or substantially reduced in their delay) within the hour before departure.

I am convinced they are meaningless in practice, because GA traffic usually flies in the great airspace void below FL200. One can fly all over Europe, airways, and not see another aircraft at one's level, say FL100-FL190. But they will delay your departure.

I've had a slot on about 10% of my flights; in one case it delayed the flight by an hour and forced a hurried re-route because the originally planned airport would have been closed.

Most slots tend to nearly disappear shortly before the original departure time! So, let's say the original EOBT is 1200, and you get a slot delaying it to 1400. You are quite likely to get changes to the slot, moving the EOBT from 1400 back to 1330, back to 1300, back to 1245... So when you get a slot delaying the flight by say 2 hours, you have to sit tight (in the plane or nearby) with a means of receiving slot amendment messages (if using Homebriefing, via SMS or email).

IFR flight plans for flights wholly within the UK

There is a bizzare twist in the handling of IFR flight plans that lie wholly within the UK. This is because, in the UK, there is a largely water-tight division between the IFR/airways controlling units, and everything flying below that. The airways traffic gets a proper service, while everything below gets something ranging from nothing at all to some kind of part-time radar or flight-information service. So, it is possible to file an IFR flight plan which lies wholly in Class G, perhaps with bits in Class D, and one of two things can happen:

a) The flight plan will be treated by ATC as a VFR one, will thus get sent to departure and destination only, you get no enroute clearance at all, and nobody enroute will know anything about you. You have been treated as if going VFR.

b) The flight plan correctly goes to Eurocontrol and is thus treated as an airways routing. You then get airborne, and on contacting the first IFR unit they will assume you have the full IR etc and will send you up into the airways. This is OK if you have an IR and have planned for this, but some pilots who have inadvertently managed to file such a flight plan have ended up tearing their hair out when they get directed into Class A airspace. London Control (or whichever authority is handling you in the relevant part of the UK) simply does not have procedures for routing pilots (which have the IMC Rating but not the full IR) around in Class G and Class D, avoiding Class A.

c) The flight plan correctly goes to Eurocontrol but they ignore it... you can continue the flight but you are not going to be able to get it elevated into the airways system.

So, if flying IFR around the UK, the best way is to either not file a flight plan at all, or file a VFR one and then change to IFR when airborne (which is just a pilot decision; no ATC clearance is needed in Class G).

IFR flight plans not taken seriously by enroute ATC

Some pilots have found that when they first contact the IFR controller after their departure, he keeps them at low level, outside CAS, for many miles. One solution to this may be to file the flight plan for an obvious and decisive "airways" level like FL120. Filing something for FL040, etc, is just asking for trouble - assuming it gets through the Eurocontrol validation in the first place.

It is much more common to get an early descent prior to arrival. ATC may be trying to do the pilot a favour by dropping him out of CAS, or they are just trying to wash their hands of "unnecessary" traffic. This may be fine if you have 30nm to run in a straight line, but is not OK if they drop you out of CAS in the middle of the London TMA and you have to work your way around, remaining below the 2500ft Class A base, in between many airfield CTAs, back home. This is a persistent complaint from UK private pilots and there appears to be no solution to it. However, the pilot is entitled to request to remain in CAS and to be given an appropriate route back home.

IFR flight plans incorrectly filed

Du to the fuzzy line between VFR and IFR in the UK, and the wide use of the IMC Rating for "informal IFR" (non-radio) in Class G, if you file an IFR flight plan through some small airfield tower facility, the ATCO may just address it as a VFR one (instead of being sent to Eurocontrol for validation and distribution enroute, it will be addressed manually to departure and destination only). This would normally happen only to flight plans which lie wholly within the UK.

The result is that, following departure, the pilot discovers the airways controlling authority (typically London Control) knows nothing about him and he will be refused a service; well initially anyway until they dig out the flight plan and re-enter it.

The best solution to this is to not use little UK airfields to file the flight plan. Use Homebriefing or fax the flight plan to a proper facility like Heathrow ATC.

Other reasons for pilots being kept outside CAS - regardless of how the flight plan was filed - can be

a) The Class G departure aerodrome failed to get them an airways joining clearance. Every airfield unit (doesn't need to be full ATC) should be able to telephone London Control and obtain an initial airways clearance; this will typically be a squawk and the initial frequency to call, and you have to remain OCAS until you are cleared by them to enter.

b) This applies to a Class G departure: The airways joining point was more than 10 minutes away from the point of departure. If this is the case then it is the pilots responsibility to obtain the airways clearance, either by requesting it from the ATC unit they're working at the time, or from the relevant FIR "info" frequency such as London Information.

c) This applies to a Class G departure: Tell the tower which is getting the airways clearance for you (when you are still on the ground) that you want an "airways join" and have already filed the flight plan via other means.

d) This applies to a Class G departure: If you are joining CAS quite a long way from the departure airfield then you have to make sure, especially if you're running late, that you get a "departure" message sent or your LARS unit (or London Info if not available) talks to the sector where you're joining CAS to activate the plan. The reason for this is if the centre doesn't hear about you within 30 minutes of your planned departure time the local Flight Plan processing system may dump your plan out of the system - when you eventually get to seek a joining clearance then they know nothing about you and you get further delayed.

En Route Billing - over 2000kg

I don't intend to cover this subject here, but will list just a few tips I've picked up. This applies only to aircraft over 2000kg MTOW, flying under IFR. Pilots operating 2000kg+ aircraft will be familiar with this.

In the UK, all night flight is under IFR; the only exception being SVFR and that is available only in a Control Zone. So any night flight is likely to result in an invoice.

If the flight plan is partially IFR (i.e. Z or Y) then the entire route is charged for, not just the IFR portion. Once a chargeable flightplan passes through a Eurocontrol address, an invoice is generated.

For IFR flights that take place outside the airways system and/or without having filed an ICAO flightplan (this is something particular to the UK; not permitted or commonly done elsewhere) the process of billing is more haphazard. Many (but not all) UK airfields report their movement logs to the CAA who in turn report them to Eurocontrol for billing purposes. Included in an airfield's movement log is whether or not each departure was IFR or VFR. The accuracy of this log, combined with the reliability of the reporting of the log through the CAA to Eurocontrol has been described as very patchy with some airfields being worse offenders for mislogged flights than others.

To avoid the charges, a lot of 2000kg+ pilots fly VFR rather than IFR. The drawbacks of this include:

a) No airways-style enroute clearance, need to sit up and beg for a transit at each piece of CAS (generally, less of a problem abroad than in the UK)
b) Cannot depart if cloudbase is below the minimum VFR departure figure for the airfield (if it's an ATC airfield)
c) The flight plan is addressed only to departure, destination and possibly some regional FIS units, and doesn't get looked at unless the aircraft vanishes.
d) In any airspace where night=IFR, night flight is not possible
e) Illegal if in IMC at any time (unenforceable...)
f) Cannot land if an instrument approach is obviously required to get in

On the last one, an IR (or IMC Rated if in the UK) pilot arriving VFR can then ask for an instrument approach, with the IFR clearance which that implies. Pilots have also reported that asking for such an IFR clearance, following a VFR flight plan, doesn't appear to trigger the en-route billing in many cases. This ad-hoc change from VFR to IFR is also called a "pop-up clearance" and some countries don't like it very much.

Filing the Flight Plan

The way the ICAO flight plan form is filled in and the physical input method are as per VFR flight plans, but there the similarity ends. Whereas VFR FPs get sent using manual addressing to a) the departure; b) the destination and possibly c) some large area FIS service, an IFR FP goes into the Eurocontrol computer and is made available to all the radar control units along the filed route.

As with VFR flight plans, one can file the FP using one of the dedicated terminals provided for this purpose at many airports.

Very recently, some countries have set up websites which allow electronic flight plan filing. These are not direct gateways into the system; instead an ATS employee checks, amends of necessary, and manually enters the flight plan. A well known one is the French Olivia but this supports only flight with one end in France. Currently, the only methods which will definitely accept an FP which lies entirely outside the country of the ATS unit are Homebriefing, and the UK NATS AFPEx system.

Homebriefing is used my many pilots and has been around a few years.

AFPEx came out in 2008 and is basically a messaging system which gives the user a direct interface into the AFTN; as such it is more complex and NATS are highly security conscious - rather pointless given that any PC can be compromised if physical access to it is not controlled. The 5MB terminal application is written in java and must be downloaded each time, which usually makes the system impractical for mobile (GPRS/3G) usage.

Loading the route into the GPS

It's desirable to load the finally accepted route into one's GPS, so at least one can see where one is going or, if ATC give one a direct-to XYZ, where one is not quite going.

Since most of the waypoints will not be navaids (and even if you get a DCT to a VOR the distance involved could be way beyond the navaid's range) it is essential to have an area navigation (RNAV) capability. In the GA context a GPS is the only practical way to do this, and legally it has to be a BRNAV approved one when above FL095 anywhere in Europe.

One needs a GPS which has a quickly accessible DCT facility. Every IFR certified GPS has this. One will spend most of the flight entering DCT to some waypoint given by ATC. It's likely to be one on the FP route (perhaps several waypoints past the next one, which is handy) or it could be something entirely unexpected. In the latter case you have to acknowledge the instruction fast (as with everything when flying IFR) and may have to ask the waypoint's spelling. What I find helpful is printing off "1 inch = 10nm" sections of the route from Jeppview; this shows the intersections and navaids on or near the route and these are most likely to be given by ATC.

The next job is how to load the route into the GPS. In many cases, any route that either gets through Eurocontrol, or gets accepted as an FP, will contain many waypoints; many more than one would fly with if doing "traditional UK IFR" flying outside CAS.

With the GPS I have (KLN94) there is no way to enter the route in the FP format containing airway references e.g.

ABCDE L217 XYZKK

where L217 is an airway with various intersections in it, changing direction at each intersection. To get the actual route into the GPS, one has to enter all the intermediate waypoints which make up L217. The immediate problem is that this can easily exceed the KLN94 waypoint limit of 20.

It's helpful to start off with a printed list of waypoints (a proper plog, ideally) that lie on the FP route, and that can be loaded straight into the GPS. Most DCTs that ATC will issue will lie somewhere on that route and such a list helps with understanding sometimes garbled instructions.

One method of getting such a plog is to run Jeppesen FliteStar/FliteMap/Jeppview and load the accepted FP into that, using the "plain text" route entry option (in Jeppview the plain text mode is the only available option). Make sure you have version 9.15 or higher otherwise the program crashes during this function. Then, printing out the routepack report gives you all the waypoints to load into the GPS - very handy! It can also be done with Navbox or manually (by tracing the airways on the paper chart) but the Jeppesen software is the only way I know where one can paste in an airways route and get a waypoint list out of it.

There is no way to exceed the 20-waypoint limit, other than missing some of the later ones out; during the actual flight one can delete the past waypoints and this makes room for those ahead. Not easy to do in turbulence. The destination waypoint should always be present, to get the GPS to show the full ETA and, if connected to a flowmeter, the reserve at destination. An autopilot is really helpful for this stuff.

The new Garmin GNS480, and recent versions of the G1000, can accept airway references directly, which would solve the waypoint overload issue.

The above isses are a good reason for not using the "reroute accepted" facility, and for working out a valid route before departure. In the case of lost comms, one is (in general; some airspaces differ) supposed to fly the clearance, the expected further clearance, and then revert to the filed route. If the filed route has been amended by Eurocontrol, you may or may not have it to hand, and if you do have it then you may have to load it into the GPS in a hurry.

Getting Notams

For VFR this is absolutely essential because one can fly around without ATC control, or indeed without using the radio at all, and one can stumble into stuff like temporary restricted areas (TRAs).

With IFR it's different. The UK is unique in that it allows IFR outside CAS, even without radio contact, and when doing that it is obviously as important to get Notams as for VFR. Elsewhere in Europe, and in UK airways, IFR is usually under radar control (exceptions being at the start and end of a flight which sometimes are done without a radar service) and ATC should not vector you into a prohibited area. So, while both en-route and departure/destination Notams are still a legal requirement, the en-route stuff becomes much less relevant and in all honesty most IFR pilots don't bother with it. The filed route is rarely flown exactly anyway so en route notams would be a waste of time (except for notifications of failed navaids). The departure/destination Notams remain very important because e.g. one can discover that the glideslope is inoperative which results in an increased DH. Or a runway can be closed, etc. On a recent planned flight to Berlin Tempelhof (EDDI) I found (from the notam) that the airport was shut (due to an air race), both ILSs were gone, the runway with the VOR approaches was shut, and the only approaches were the NDB ones!

One can get Notams from many places but the standard UK source is National Air Traffic Services (NATS) site which offers a unique feature (for a free website, anyway) of a narrow route briefing where the route is entered in the standard FP format. As per ICAO agreements, this site is not authorised for briefing for flights which lie entirely outside the UK; they have to say this otherwise everybody would use the best free website (which is exactly what happens on the internet anyway !!!!!) and overload it. The reality is that the NATS website should be good for any flight between international airports. It has to be because if one had an aircraft with a 15000nm range one could fly to any international airport direct from the UK. I know for sure that the French intentionally withold Notam data for their non-international airports (series D notams) from non-Schengen Notam data subscribers (such as the UK), presumably on the grounds that nobody from those countries can legally fly direct to a non-Customs French airport anyway. Homebriefing also offers notams but only if you file a flight plan first!

Very occassionally, notams are crucial for enroute too. A flight plan can be rejected due to an airway being closed due to e.g. military activity, and a narrow route notam briefing (done over the failed flight plan route) should give an idea what the problem is. Do a text search of the whole notam listing for the offending airway name.

Weather

This is just a quick bit on weather related planning for IFR.

For a pilot legally limited to VFR, weather is horribly limiting. In the UK, the IMC Rating (privileges, in short, are those of an IR but UK only and below Class A) opens up the options substantially, but they don't teach the pilot a lot of tricks on weather planning. The JAA IR (which I haven't done) is reputed for containing a vast amount of theoretical material on how weather works. However, no interpretive skills are going to be of any use if one cannot get the data; I think that what is really needed is a selection of good accessible (nowadays this means the internet) weather data sources from which one can rapidly build up a picture.

At this point, it's worth examining the often quoted phrase "official weather data". UK ANO (2005 version) Article 52(a) merely states "the latest information available as to the route and aerodrome to be used, the weather reports and forecasts available". It's reasonable to assume that a TAF, where available for the destination, meets this requirement but I have not found any regulation which lays down what is or isn't "official" and other weather data should meet the requirement too if reasonably current. This is true for both G-reg and N-reg operation.

Perhaps the most obvious place for UK weather data is the UK Met Office (UKMO). Personally I prefer Avbrief as they provide a better compilation of data for Europe. This free facility run by Avbrief is perfect for people on GSM/GPRS who want just TAFs/METARs while transferring only the absolute minimum of data.

There is no doubt that the best short-term weather data comes in TAFs and METARs. TAFs are produced by full-time professionals. METARs are accurate, being observations. The Met Office Low Level forms 214 and 215 are also good - even if 215 does tend to show a variety of weather and one can take one's pick! The European versions from Avbrief are 414/415. The SigWX charts perform a similar function to 215, for Europe, with the information very usefully limited to FL100-FL450, but there is a vital difference: the SigWx does not forecast vertical cloud extent; the vertical extents of the scalloped areas apply to the icing or turbulence only.

One problem for any pilot wishing to go away for a few days or more is that no "official" data is available more than about 24 hours ahead. There are only the MSLP charts (5 days ahead) which show the pressure and fronts and require skilled interpretation and guesswork for anything beyond the obvious like "here's a warm front; that's low cloud, high tops, drizzle and it will clear slowly". For large airports one can get long TAFs which are usually OK for a decision whether one might fly the following day. However, for locations for which no nearby long TAF exists, or for further ahead one has to go elsewhere, and the most common data is GFS (Global Forecasting System). GFS is a global weather model run by the USA.

A Google for "GFS weather" digs out countless websites that provide gateways into GFS, with a huge variety of presentations. A lot of these are run by/for the US Military and sometimes it's funny to note that one can enter airport identifiers like EGKA but not LFBZ (France is not in NATO).

One must be a little careful with the countless amateur weather websites, as they may present ordinary data (TAFs and MSLP charts) which is a lot older than what's available from UKMO or Avbrief. In Europe, the national weather providers like to charge a lot of money for data, so there is a big incentive for providers to get it from somewhere abroad instead. I have used some services which return a TAF in an SMS message, only to find that occassionally it was 2-3 days old!

My favourite GFS site is NOAA and I choose MSLP, 2 metre temperature (which also shows the DP), accumulated precip, total cloud cover, wind speed and wind flags. There are many other results one can pick; e.g. the 3D temperature as a specified millibar level gives a graph of the temperature up there, over time. One has to be careful in the way one mixes different results in the same run; the 2D and 3D don't appear to be compatible.

It's been said by some UK weather experts that the UK Met Office weather model is more accurate than GFS. Certainly, GFS does not model local effects such as fog and sea breezes. On the basis that weather forecasting is (quite obviously in my view) more accurate in what happens than in when it happens, a good tactic is to use the UKMO MSLP charts for timing information (look at the positions of any fronts, particularly) and use GFS for filling in the detail. Ultimately, when looking a few days ahead no forecast is likely to be accurate but this is a lot better than nothing. The UK Met Office does not release much information beyond this, presumably because they sell it to commercial weather data re-packagers.

This site in Wyoming is also very useful for Skew-T diagrams. These are also called "ascents" because they come from weather baloon ascents. Another name is a tephigram or tepigram, explanation. For Region, select Europe; for Type of Plot select GIF: Skew-T, and you get what amounts to a METAR map of data gathered from met baloons which go up every 12 hours. The generated diagram shows the profile of temperature and dew point versus height and this gives an immediately obvious (and accurate, at the time) figure for the cloudbase and cloud tops, freezing levels, etc. Another site is Univ of Cologne which presents both skew-t and tephigram charts.

The above are actuals; if you want forecasts you have to go to the Meteoblue site which offers various graphing options including tephigrams (a version of the skew-t) and cloud profiles over a straight-line route.

A TAF or METAR reporting SCT030 is permitted to omit the fact that there is a separate solid layer from 6000ft to 15000ft; in fact anything above 5000ft does not have to be reported.

The Dundee satellite station is one of many sites offering satellite images of various earth regions; great for seeing where the cloud cover is.

Cloud Tops

In any GA aircraft, the name of the game has to be to get VMC on top as soon as possible, for reasons of icing, turbulence or simply to get some warmth! Unfortunately, there is little good data available on where the tops are. They are fundamentally hard to forecast. Often, it will be visually obvious from looking up from the ground through a scattered cloud that it is only 1000-3000ft thick and one can safely climb up through that, especially with a de-iced propeller. Otherwise, one often faces a situation something like this: a uniformly dark sky, MSA=2000ft, base=2000ft, 0C level=4000ft, tops=?? and if the tops are at 5000ft that is OK (only 1000ft of freezing IMC to climb through) but if the tops are at 10000ft then you have 6000ft of freezing IMC to climb through!

Of the "official" data, the UK Form 215 contains any indication of tops, with varying usefulness as F215 usually shows a whole collection of different weather for the same area. It is possible to derive cloud tops from GFS data; the NOAA site given above has a "Soundings" function; also the aforementioned Meteoblue site (which I assume uses GFS data; they acknowledge "cooperation with NOAA") has a good go at it. The SigWx form looks attractive but in fact it does not forecast vertical cloud extent; the vertical extents of the scalloped areas apply to the icing or turbulence only.

The only accurate tops data is the Skew-T weather baloon data (see the Wyoming site given above) but they are generated only at 0000Z and 1200Z; the former is at night (in Europe) which is usually very different from daytime, and the baloon launch sites are well apart. This isn't normally very useful for flying, unless one can depart shortly after the data has come out.

Warning: It has been suggested (I have not been able to verify this) that the Meteoblue site may indicate the tops of stratus cloud only, and therefore cloud with significant vertical development is not indicated. This is still useful, since once one is above any organised"" IMC then one can avoid the nasty stuff visually. To get an idea of the extent of cumulus cloud, one needs a good understanding of tephigram/skew-t charts and how the temperature lapse rates shown therein relate to atmospheric stability.

Cloud tops forecasting, whether from Meteoblue, or from any other source, remains high unreliable and you will be lucky to get cloud tops accurate to within a few thousand feet. An article dealing with tops specifically is here.

Icing

This subject generates a lot of passionate debate between pilots; suffice to say that it can be divided into legal issues and practical issues. I will have a go below:

For an N-reg aircraft, you have to comply with FAA regulations and directives (as well as any local ones, where more restrictive), and some years ago the FAA had decreed that forecast icing constitutes known icing. This has been to some degree superceeded in the 2005 AIM which separates the two, and I am not aware of any case law developments since. If this recent development is disregarded, you would be illegal upon departing into forecast icing in a non-KI (KI="known ice certified") aircraft. Simple! Not so simple, because there are weather forecasts in the USA which forecast icing over huge parts of the USA and are thus obviously unrealistic. The consequence of this position would have been even less clear outside the USA, a) because the original FAA position was probably based solely on U.S. weather services; b) in the UK, the standard Met Office Form 215 carries the patently stupid statement "moderate icing in cloud" (on the new 2006 F215 the same thing is stated symbolically) every day and is thus forecasting icing in every cloud, not just freezing cloud. To argue in support of this being a "known icing" forecast is arguably unrealistic.

For a G-reg aircraft, there is no case law, or clarification that I know of, on the relationship between forecasts and icing certification. The European icing certifications specify categories of icing severity for which the aircraft is certified to operate; if the conditions exceed the certification category then the pilot is supposed to do something about it. This suggests that a departure into freezing IMC is not illegal in itself.

That's a summary of the legalities. Now onto the practicalities. On a strict view one would not even touch a cloud if the temperature is below 0C, which is unrealistic as it would practically prevent winter IFR, or any IFR at airway levels, in any aircraft not certified for flight into icing, which is the vast majority of singles and most piston twins. The reality is that flight in stratified cloud is most of the time either ice-free or one picks up only a few mm of rime, so in my view the issue becomes one of managing the risk and having exit options.

My tactic (flying an aircraft with a TKS de-iced prop but no other anti-ice equipment) is to scrap any flight where the forecast or actual 0C level lies below the en-route MSA - unless there is clear information on cloud tops which enables the flight to be done VMC on top. This procedure does prevent many flights in the winter where the cloud layer is several thousand feet thick and the bases are below the MSA - that is just the price one pays for not having a turbocharged aircraft with all-over de-icing. This takes one back to the question of how to find out the thickness of the layer - see "Cloud Tops" above.

A huge amount has been written on the practical aspects of icing. Here is an online NASA course on it. This site, under "flight hazards", offers what looks a useful icing chart. Some useful snippets: Icing is unlikely in stratified cloud below -15C i.e. about 7000ft above the 0C level. In cumulus cloud it can happen down to -25C. The areas where icing takes place are relatively small in vertical extent so a 2000ft climb or descent is likely to stop further accumulation even if the OAT remains below 0C. If you are in rain and the OAT is showing +1C then watch the OAT carefully; the most likely exit will be a descent as the ice buildup from freezing rain will be rapid and there better not be any terrain down there... Freezing rain: there is an alternative argument for freezing rain: it must be coming down from a warmer layer above, so climbing should help. A NASA article on freezing rain is here (local copy) and from the data in there (freezing rain layers can be up to 12000ft thick) it's clear that the best thing is a rapid 180 degree turn and get out of there. Another freezing rain article is here (local copy) and this confirms the aforementioned NASA information: freezing rain is not to be played with and one has to get out fast. Speed helps: due to aerodynamic airframe heating: (the following is at 5000ft and 0C, approx mach heating figures) 0.5C at 100kt IAS, 3.3C at 150kt IAS, 6C at 200kt IAS, and it's pretty obvious that a jet doing 300kt IAS will almost never ice up because its airframe will be 14C above the static air temperature (SAT). It's suprising how quickly the ice melts and falls off when transitioning from a 95kt climb at -1C to a 170kt descent; the OAT rises to +2C almost immediately due to aerodynamic heating. Note that the OAT probe temperature is a lot closer to total air temperature (TAT, this is SAT corrected for TAS) than it is to SAT; almost anything sticking out in the airstream will experience a similar sort of heating to the wings and other bits of the airframe. I religiously use the TKS prop de-ice whenever in IMC below +1C. Working out the TAT figures suggests it should be a lot harder to ice up a prop than the airframe but one of the above articles contains an explanation for this not being the case: on rotary objects like props, evaporative cooling takes over and the prop can still ice up nicely.

I've often picked up a few mm of rime ice and my view is that rime ice is nothing to be afraid of provided one has escape options; usually a descent below the 0C level once it gets beyond several millimetres in thickness. Some aerofoils do not like ice at all, however.

Convection

The other problem with flight in IMC is convection. Flying into a CB is dangerous but cannot be avoided if it is embedded in other cloud. I scrap any flight where CBs are forecast (or, any cold front) where one is likely to be in IMC at the time. An exception to the foregoing would be where the CB bases are forecast to be at least 2500ft AGL and there is no significant terrain; however we are then looking at a VFR flight anyway. It's best to scrap a flight where one might be passing through a cold front in IMC.

I have a WX500 stormscope but no radar. I've seen turbulence strong enough (CU/TCU most likely) to bang my head on the ceiling and throw off the headset, with nothing at all showing on the stormscope, which would show only electrical activity. On the other hand, I have seen (in VMC, from a distance) the sort of stuff that does show up strongly on the stormscope and one definitely doesn't want to go anywhere near any such group! I think a stormscope is highly desirable, and not expensive.

If turbulence is encountered, one must slow down to Va or slower. Often, this means flying the entire distance at below Va - also true at night even if in VMC because if the night is dark enough you never know what you will wonder into.

At a lower level of the problem, it's best to avoid prolonged flight in IMC with passengers as most people really dislike turbulence with no visual references. Sometimes this cannot be helped though, and I have found that this can be a huge source of stress. It's stressful when planning the flight to know the passengers are going to get scared and probably won't fly again, and it's much more stressful during flight when somebody gets scared but nothing whatsoever can be done about it. Flying an ILS through the bottom part of a TCU is hard enough without the passengers panicking. While the pilot must fly the aircraft regardless (and switch the intercom to "pilot only" if necessary) I am certain that many fatal accidents have been caused by this, quite pointlessly.

So the objective is to get high enough to be VMC en-route if at all possible and, if not, avoid carrying passengers that are even very slightly nervous.

Another problem, really big in the UK where few airfields have an instrument approach, is what to do about getting back down through IMC. In the UK there is no prohibition on flying below the MSA, IFR, if for the purpose of takeoff or landing. In other countries, e.g. the USA, this can be illegal - FAR 91.175 makes this illegal in the USA but may or may not be applicable outside the USA... So, how low should one go? I suspect a lot of people could tell some scary stories here. I would go down to 1000ft AGL in OVC conditions, having done a position fix using two independent methods of which one is GPS. Accurate navigation is essential in IMC anyway; the whole concept of MSA goes out of the window without it. I have gone down to 700ft AGL in SCT/BKN conditions and that is really my limit. It's much safer to fly down somebody's ILS and then proceed VMC to the destination - if one can get it. Or a "radar letdown" from a military radar unit. This issue causes many intra-UK IFR flights to be scrapped during planning.

Lightning data

This can be obtained in two ways: weather radar, and lightning discharge detection technology called "sferics". Weather radar data is normally sold to commercial organisations and is thus closely controlled, but free websites showing radar images of large chunks of Europe are increasingly appearing. Sferics is much easier and there is a large network of home-based detectors, many connected via the internet and correlating the data. On my links page there is a Weather Radar/Sferics link which is a good starting point. The latest development on the radar scene is Meteox who I am sure have upset a lot of commercial weather resellers but this gives key flight safety information for pilots. Unfortunately Meteox doesn't cover all of Europe and has large gaps in its coverage which are not in any way obvious (e.g. Northern Italy).

Data when on the move

When I started JAA PPL training in 2000, the instructor pinned a local FIR Notam printout on the notice board, and that was the full extent of Notam "training" within the PPL. It's useless for going anywhere. The UK Met Office Forms 214/215 were pinned next to the Notams and that was the full extent of "getting weather"; only marginally less useless than the Notams. Flight plans would be filed using a dedicated terminal (a PC hacked so it could not be used for anything else) at the tower, and if you typed in something stupid, a red phone next to the PC would ring and ask you to clarify.

This is still how a lot of people fly, but it's no good for going places - whether VFR or IFR. One cannot check out of the hotel, travel to the airport with all bags packed, and then mess about trying to get weather, file the flight plan, etc. Especially as the best time to fly, weather-wise, tends to be early in the morning. A lot of airports do have the services but they can be hard to find, hard to use, or they can be in the main passenger terminal which could be miles away from the GA facility. Or it could be a dedicated machine which happens to be broken. In Switzerland, I found the dedicated machines are seemingly everywhere and of course nothing in Switzerland is ever broken!! I just couldn't work out how to use them...

So portable data access is highly desirable. It can be easily enough achieved with any laptop computer, by plugging in a GPRS or 3G data card. One can buy such cards below £100, especially on Ebay, and they are available badged with e.g. Vodafone (PAYG SIM card included) and bundled with simple to install software. Just click on a CONNECT button and you have a standard internet connection. It works just about anywhere in Europe where there is GSM (mobile phone) reception. Occassionally one has to manually select a different network. The speed compares with a cheap dial-up modem and the charging is per kilobyte so it's OK to stare at an MSLP chart on a web page for an hour... GPRS is not cheap but even at £10/MB a comprehensive preflight briefing, with MSLP and other charts, and FP filing, can be done for say £3.

Most GPRS cards will also do FAX, using an application such as Winfax. The ability to send a fax is occassionally handy but is particularly necessary when flying between the UK and Europe for advising Immigration, Police and Customs of the flight and passenger details. These outfits do not have websites and only one can use email. However, there are commercial services (fax to email gateways) which will convert an email to a fax or vice versa.

If the laptop has WIFI (also known as 802.11) then one can get broadband-speed internet when within the range of a public WIFI access point. These can be plentiful in cities; many are available without the owner realising it. On a 10-mile drive through a nearby town, I detect about 85 of them, of which about 50 are insecure (open) and I bet none of them intentionally so. Cafes often have public WIFI; hotels likewise but they usually charge a lot for it. But finding an open WIFI access point can be impossible right when one needs it, so I generally stick to GPRS/3G which works practically everywhere.

I have had to play around fairly extensively with this stuff for non-aviation reasons, and dedicated gadget fans with plenty of time and patience can achieve mobile internet in a multitude of ways. One can set up a laptop or a tablet PC with WIFI, GPRS, 3G (in short, broadband-speed GPRS but coverage is currently very patchy), and all imaginable flight planning software. One also can do it all (except any decent flight planning software) with a high-end PDA (a pocket-sized device running a version of Windows even more flimsy than the standard version). It's even possible to do voice (telephone calls) over an internet connection, at rates way below that of a roaming GSM mobile call, but GPRS wouldn't be fast enough.

There are ways to get short amounts of data; TAFs and METARs, on any mobile phone using SMS. A number of commercial outfits offer this.

If using any of the above GSM/GPRS internet access methods, do make sure that you have disabled all automatic updating of Windows, antivirus software, browsers (Firefox etc), Adobe PDF writers, etc, otherwise it's possible to run up astronomical bills without realising it.

Mobile internet isn't cheap. Most websites were designed for flat-rate broadband access. There are a few ways around this, however:

This is a very compact site for TAFs and METARs which gets you what you want in just a few k. There are a few others but you have to be very careful with where the data comes from; out of date TAFs are common on some of the amateur weather sites.

Flying

The process involves the following steps:

(a) Getting an IFR flight plan accepted by the system. It should be filed 3 hours before the flight planned departure time. This isn't a hard rule but time slots are allocated 2 hours before the planned departure time so if you file it later than that you may not get a slot. The degree to which this matters in practice depends on the route; routes into France and Spain are a lot less congested than routes into Belgium for example. In reality the flight plan is distributed to the IFR sectors within seconds of getting accepted by CFMU and in most cases one can depart almost immediately.

(b) Getting an IFR departure clearance (DC) while still on the ground. This will give the current SID in use, so you need to have all the possible (or likely, given the departure runway/direction) SIDs to hand and have studied them beforehand. If departing from a field in Class G, the DC will be a provisional one with a squawk, an instruction to remain OCAS, and a contact frequency for the IFR sector controller (e.g. London Control).

(c) Departing on the SID. Often, one is asked to contact a radar unit early on which takes over control and once a heading is assigned the SID is no longer relevant (and ATC should then assign a new altitude or level). However, if an altitude or level only is given then you must still fly the SID laterally because the SID is the lateral clearance. At this point you are under radar control and in Europe will generally remain so for the entire route. This conversion from the assigned SID to radar control, well before the SID is exhausted, is very common.

One should query any SID given whose end point does not connect to one's filed route; the reason is obvious but a more subtle reason concerns the lost comms situation: how are you going to revert to your filed route if the SID takes you off in a totally silly direction? Sometimes, incorrect SIDs do get assigned by busy ATC.

If departing from an airfield which doesn't have a SID (usually, one in Class G) one departs as per the tower instructions.

If the airfield does not have any instrument departure, technically you should file a Z (VFR to IFR) flight plan. However, it's better to file a fully-IFR FP ("I") because that gets you into the airways system faster, even though the initial part may be under VFR. Same if flying into such an airfield; the arrival is under VFR but one doesn't bother with that in the flight plan; just "cancel IFR" some 20 miles out and ATC will get rid of you there and then. In the UK, one has the bizzare and wonderful option of departing from any old grass strip in Class G and once airborne calling oneself "IFR".

(d) Fly the route. ATC will give you "DCT" or "own navigation" clearances most of the way, with vectors in busy areas, so one rarely flies the filed route exactly. It's not unusual to do a 200nm route section with vectors the whole way. More typically, the route is flown as filed but with many shortcuts.

The general strategy in IFR flight is to climb to VMC on top and stay there. The filed route will have been filed at some level which passes the Eurocontrol validation, but you are not bound to this as a lower limit; two exceptions: cannot fly below an airway MEA unless authorised by ATC (and they will want to be sure you are in VMC); cannot generally fly below the base of controlled airspace (again, ATC can allow this at times). There is normally no upper limit on IFR flight; one can file a flight plan for FL100 and request a climb to FL250 "due weather" as required. One common tactic is to file a flight plan for the lowest level acceptable to Eurocontrol, or the forecast tops plus a few thousand feet, and then ask for a "stop climb" once in VMC.

(e) Arriving on a STAR. ATC will give you the current STAR, often not long before the first waypoint of the STAR is reached. So you need to have all the possible STARs to hand at this point and have studied them beforehand. As with a SID, the STAR to expect is one that connects to the filed route. Often, the STAR is not flown because one gets radar vectors to the ILS, to the localiser or to a VOR approach, and often one can ask for radar vectors instead of flying the STAR (it's a whole lot less work). If the destination is outside CAS then they will drop you out of CAS at some point and you may be offered the option of proceeding VFR. In the UK you can remain IFR at this point, under own navigation and (if you can get it) with a radar service from elsewhere.

Cancelling IFR: Beware of reverting to VFR in unfamiliar territory - no matter how good the weather is - because it throws you back in the old world of VRPs and other stuff which needs VFR charts, VFR airfield data, etc. The instant you are VFR, the whole IFR world with its predictable structures and procedures has washed its hands of you. However, as per the "VFR-only airports" note earlier in this article, some countries give you no choice (CFMU rejects an "I" flight plan) when using an airport with no instrument procedures, so in those cases you do need to carry at least the VFR charts for the airport.

IFR or VFR? There is occassional confusion among pilots, including many professional (airline) ones who don't know the subtle differences. If you arrive IFR and request a "visual approach" that is still technically IFR, but if you arrive IFR and ask for a "VFR approach" ATC could interpret that as you having cancelled IFR some way back. This is quite likely to happen in the UK where there is the watertight wall between "airways" traffic (for the most part in Class A), and everything else underneath that where the rules are more fluid especially at Class G airports with instrument procedures. If you fly an ILS and ATC think you are VFR, they will not give you the same separation from other traffic as they would if they thought you were IFR. Outside the UK, this confusion (within ATC) would be rare but in the UK it is easy to arrive IFR, from a Eurocontrol airways flight, and be treated as a VFR inbound. So, if you want the IFR treatment, let ATC know in no uncertain terms that you are "IFR".

Oxygen is desirable; I find that it keeps me more awake at FL100 and makes a big difference at FL120. The TB20 has been to FL190 and up there it is essential. A lot of people get headaches or blurred vision at FL120, without necessarily realising the cause. Even at FL080, where most pilots would claim (probably optimistically) to be completely unaffected, oxygen keeps one's mind sharp, and the required flow rate is very low. At FL120 one is likely to spend a lot less time sitting in cloud than at FL080, especially in the summer when the tops are higher. Even in the summer, the icing level is unlikely to be above FL100 (in Northern Europe) so the extra height capability is very handy. Moreover, the ability to file a flight plan at say FL160 can dramatically increase one's routing options - even if the actual flight is done flatly at FL100.

In stratus cloud, icing happens a lot less often than one would expect from purely being in IMC at below 0C but if you do it for a few hours, icing is a virtual certainty and one has to do something about it within minutes. I have a de-iced (TKS) propeller so prop icing is a non-issue (as is windshield icing, due to the amount of TKS fluid ending up all over it) but about 5mm of rime ice on the wings is enough for me and it shows up as a ~ 5kt loss of speed! So this is another flight planning issue; with two people and say 4 hours each way, one will use up a pretty big bottle at FL120+. Very few European airports are geared up for refilling portable bottles; if oxygen is available the threaded fittings tend to be for pressurised aircraft (where oxygen is used only in emergency) and filling up portable bottles is a huge hassle and like anything in aviation where they can smell money it can be very expensive (I once paid £75). Eventually I got sick of the hassle and now I rent the biggest available welding oxygen bottle from a local British Oxygen gas dealer; it costs relative peanuts at £90/year rent and £18 for a swap/refill. I can get 10-20 refills from this bottle. If I was doing this again, I would buy a bigger bottle for the aircraft. More info on portable oxygen kits here. Oxygen is all but essential for European IFR flight; without it you throw away about half of your operating ceiling, and throw away the most favoured weather avoidance option (climb to VMC).

Other Stuff

For a mostly-VFR pilot, there is a new "language" to learn. When learning to fly, one can hear it but one cannot understand much of it. Eventually, as with any other spoken language, one knows what to expect from the context and that is how language works. I very often fly with non-flying passengers and in almost every case of me not understanding something, they didn't catch it either. Non-UK controllers occassionally speak poor English, or (especially further south in Europe) use dubious / ambiguous phraseology, which makes things worse.

Most VFR pilots do very few hours and many are struggling with decrepit aircraft fitted with decrepit equipment and radios. So, any pilot with a few hundred recent hours will find that his own radio procedure is better than most of what he hears from others on the air. However, with airways flying, you are back to square one! There is a new chunk of context to learn, and you have to be quick, because every other pilot on the radio says the same things several times a day, all their working life. ATC gives you about 5 seconds to read back an instruction and if you don't they will remind you. On the other hand, there is a lot less variation in what ATC might ask you to do, and communications are better because a lot fewer people fly IFR in aircraft with decrepit radios.

When changing to a new frequency you officially have two minutes before calling the new unit and it's best to get everything sorted out and, as with any flying situation, know what to say before making the radio call. The information that needs to be passed on the initial call is only the callsign and the level, or the heading (to nearest 10 degrees). In UK IFR flight outside CAS but under a radar service, on a handover to a new radar unit, one passes the callsign and the other information depends on the method of handover.

My estimate is a few hours of flying to get up to speed on the language and what to expect most of the time - not hard at all.

European IFR flying is really easy 99% of the time - usually much less stressful than VFR where one is hoping for transit clearances through CAS which are sometimes not given and a last-moment re-route is necessary. Not to mention having to keep officially clear of cloud... The other 1% of the time, IFR brings a high workload, e.g. trying to find some waypoint - especially if they have given the name of the place rather than the ID of the navaid. It's a good idea to immediately ask them to spell anything that isn't clear. The spelling uses the aviation alphabet: ALPHA, BRAVO... ZULU.

The other tip I have found: when within say 100 miles of the destination, ask the current ATS unit to get you the current runway at the destination. This will enable you to sort out the STAR and approach charts, with the most likely ones at the top of the pile.

It's a perverse observation that the hardest flight training and the hardest exams are used to give the pilot access to the easiest way to fly...

IFR flight is for the most part very structured and predictable and this results in a much lower cockpit workload than with VFR, especially for long distances.

I have written up some IFR trips which contain detailed flight planning examples: Prague Corfu Crete Zaragoza Granada.

Flight Planning Software Update

In 2005 Jeppesen discontinued the FliteMap product, leaving FliteStar (which doesn't have a GPS input and can't do a moving map) as the main GA flight planning product. However they also integrated most of the FliteStar flight planning features into Jeppview v3 (Jeppview was basically an approach plate database and viewer) and JV3 now includes FliteDeck which is Jepp's only GPS moving map product.

What you don't get from JV3 is a plog (a list of waypoints, times, headings, tracks, etc) which is a huge omission for a flight planning program. You also don't get the "semi-automatic" airways routing nor the ability to load the Jepp "VFR raster charts". So, Jeppesen have crippled Jeppview 3 just enough to make you buy Flitestar as well...

Jeppesen also now offer an internet-based version of Flitestar: the JIFP. They do not yet offer (for Europe) an online version of Jeppview i.e. online approach plates.

Last edited 24th December 2008.

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