Notes on FAR Part 91 outside the USA

General

Subpart 91.1 says that part 91 only applies within the US, "Except as provided in ..... Secs. 91.701 and 91.703". So this is what applies outside the US:

Sec. 91.703
Operations of civil aircraft of U.S. registry outside of the United States.
(a) Each person operating a civil aircraft of U.S. registry outside of the United States shall--
(1) When over the high seas, comply with annex 2 (Rules of the Air) to the Convention on International Civil Aviation and with Secs. 91.117(c), 91.127, 91.129, and 91.131;
(2) When within a foreign country, comply with the regulations relating to the flight and maneuver of aircraft there in force;
(3) Except for Secs. 91.307(b), 91.309, 91.323, and 91.711, comply with this part so far as it is not inconsistent with applicable regulations of the foreign country where the aircraft is operated or annex 2 of the Convention on International Civil Aviation; and
(4) When operating within airspace designated as Minimum Navigation Performance Specifications (MNPS) airspace, comply with Sec. 91.705. When operating within airspace designated as Reduced Vertical Separation Minimum (RVSM) airspace, comply with Sec. 91.706.

So the only exceptions from Part 91 in non-US airspace (except if it clashes with local or ICAO rules) are 91.307 (Parachutes and parachuting), 91.309 (Towing gliders) , 91.323 (Increased MTOW in Alaska) and 91.711 (Special rules for foreign aircraft in US airspace).

FAR 91.175

This is an interesting example of the interminable debate around how FAA rules (drafted mostly with only the USA in mind) apply in the UK, or outside the USA generally.

91.175 states: Unless otherwise authorized by the FAA, when it is necessary to use an instrument approach to a civil airport, each person operating an aircraft must use a standard instrument approach procedure prescribed in part 97 of this chapter for that airport.

In the UK, the practice of carrying out a DIY letdown through IMC is not prohibited (which means it is permitted) on private flights, despite a abortive attempt by the CAA a few years ago. It is widely done, not least because most of UK's GA airfields do not have published IAPs.

Moreover, many UK airfields have IAPs which were once real but became unpublished after ATC left (the CAA requires, among other things, full ATC for any airfield with an IAP, and this expensive); these IAPs are still known to the locals who use them.

At other airfields, pilots do their own procedures, usually based on GPS.

FAR 91.175 appears to make this illegal with an N-reg aircraft.

However, the applicability of 91.175 outside the USA, and where local law is more permissive, is a grey area.

If 91.175 were generally applicable to for example the UK (where all night flight is IFR), an N-reg aircraft operating IFR at night could not land at an airfield without an official IAP. In the US you have to cancel IFR to land at such an airport, but you can't do this at night in the UK. 91.177 is minimum height except for take off and landing and 91.175 gives the rules for that phase. The situation of being visual and IFR into a VFR field is not allowed for yet is clearly intended to be legal in the UK.

Another view is that this doesn't matter much in practice because one can legally fly an N-reg in IMC, OCAS (i.e. Class G) at the MOCA (in non-mountainous terrain, this is 1000ft above the highest obstacle within 4nm of track) without ATC clearance and if the airfield becomes visible then one can execute a visual approach; this amounts to the same thing as an IAP with an MDH of 1000ft - not unreasonable.

Interestingly, an instrument rated (UK IMC Rating or a JAA IR) pilot, flying a G-reg aircraft, can legally descend down to zero height in the UK for the purpose of a landing, so it appears that, within the UK, a pilot who is flying a G-reg on his IMC Rating has greater privileges for DIY approaches than if he is flying an N-reg on the FAA IR.

Outside the UK, 91.175 isn't a problem anyway as IFR flight OCAS isn't normally done, and an IFR flight would terminate at an international airport, with an IAP, anyway.

This page last edited 1st February 2008