From: lhe@sics.se (Lars-Henrik Eriksson)
Subject: Re: Another trivia question
Organization: Swedish Institute of Computer Science, Kista
	<1992Oct1.003930.20736@mintaka.lcs.mit.edu>
Date: Thu, 1 Oct 1992 08:43:06 GMT

In article <1992Oct1.003930.20736@mintaka.lcs.mit.edu> mikec@tabasco.lcs.mit.edu (Mike Ciholas) writes:
   Depending on just how hard you squint at the international regulations
   and local interpretations, this flight may or may not have been legal.
   Some say the more restrictive of the two countries rules are in effect
   (what happens if the rules can't be compared?  Suppose country A's
   rules say to fly upside down during cross countries, and country B's
   rules say to fly right side up.  Which wins?).  Others believe you can
   consistently use one set of rules or the other.  A third
   interpretation is that you can only use the ICAO rules.

   I am sure there will be further discussion on this topic...

This question is rather messy. The only things that are certain is
that you *cannot* consistently follow one set of rules, and that you
always safe if you follow the most stringent rule - of course this may
inconvinience both you and ATC to arbitrary degrees. However the
Chicago convention on international civil aviation and its Annexes do
give some information. (The following discussion assumes that the same
country issued the pilot's license and registred the aircraft being
flown.)

Basically there are three kinds of rules (that are of interest to us
here...), certificate rules, operational rules and rules of the air.

Rules of the air are the easiest part. Those are stuff like
right-of-way rules, VMC minima, clearance requirements and the like.
On any flight, you follow the rules of the air of the country you fly
over, without exception. If you fly over international waters, you
apply the ICAO standard rules of the air (Annex 2), without exception.

Certificate rules deals with rules for issuing and renewal of
certificates, often also rules for currency. Since the Chicago
convention obliges each ICAO member country to accept the certificates
of other member countries. E.g. in Sweden, currency rules for IFR
ratings - which are different from those of the U.S. - are certificate
rules. This means that a pilot with a U.S.  certificate flying in
Sweden do not need to apply Swedish currency rules, since he doesn't
have a Swedish certificate. However, currency *may* be an operational
rule - in that case the situation is different.

Operational rules deal with rules about what is required to operate an
aircraft on a specific flight, this is the place where you would find
parachute rules. Basically, you have to apply the operational rules of
your home country wherever you fly.

Sweden has a rule that a private day VFR flight must not commence
unless all available MET info shows that you will have a flight
visibility of at least 5 km and a cloud base of at least 1000 feet.
These are *not* VMC minima. If the forecast is wrong, you may legally
go on flying down to ordinary real VFR minima (in most cases this
would mean 3 km visibility and 500 feet cloudbase). This is a similar
kinf of rule as the U.S. rule on parachutes for aerobatics. Another
example is that Germany requires an autopilot for all single pilot
IFR.

Now, does a foreign PPL in Sweden have to follow this weather rule?
Does a British pilot in the U.S. have to wear a parachute during
aerobatics? Does a French aircraft flying IFR in Germany have to have
an operating autopilot?  That depends. I would think not - in general.
I believe that any country *may* - but does not automatically - impose
its own operational rules on overflying aircraft.

How do you know if a particular rule is a certificate rule, a rule of
the air or an operational rule? Well, the ICAO regulations and many
national regulations make the distinction pretty clear. Possibly the
U.S. FARs have different parts for this. To me, part 91 and part 135
sound like operational rules.
--
Lars-Henrik Eriksson                            Internet: lhe@sics.se
Swedish Institute of Computer Science           Phone (intn'l): +46 8 752 15 09
Box 1263                                        Telefon (nat'l): 08 - 752 15 09
S-164 28  KISTA, SWEDEN                         Fax: +46 8 751 72 30
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