Only official instrument approaches authorised under FAR?

In article ,
Peter wrote:

FAR 91.175 (a) suggests that it is not permitted to carry out a
descent in IMC except on an official published IAP.

It does more than suggest, it states it quite explicitly (for most of us,
neither of the exceptions are likely to apply):

"Unless otherwise authorized by the Administrator, when an instrument
letdown to a civil airport is necessary, each person operating an
aircraft, except a military aircraft of the United States, shall use a
standard instrument approach procedure prescribed for the airport in part
97 of this chapter."

How would it differ if the entire procedure was done in Class G?

Not in the least. All IFR rules apply in class G except for the
requirement to obtain a clearance.

"Peter" wrote in message
...

FAR 91.175 (a) suggests that it is not permitted to carry out a
descent in IMC except on an official published IAP.

Any views on this?


FAR 91.175 (a) suggests nothing, it states, "Unless otherwise authorized by
the Administrator, when an instrument letdown to a civil airport is
necessary, each person operating an aircraft, except a military aircraft of
the United States, shall use a standard instrument approach procedure
prescribed for the airport in part 97 of this chapter."



How would it differ if the entire procedure was done in Class G?


It wouldn't differ in any way, the regulation is not limited by class of
airspace.

In a previous article, Peter said:
"Steven P. McNicoll" wrote
FAR 91.175 (a) suggests nothing, it states, "Unless otherwise authorized by
the Administrator, when an instrument letdown to a civil airport is
necessary, each person operating an aircraft, except a military aircraft of
the United States, shall use a standard instrument approach procedure
prescribed for the airport in part 97 of this chapter."

Does that mean that, on an IFR flight, one is not allowed to descend
below the MOCA except on a published IAP?

It says "when an instrument letdown...is necessary" that you shall use an
instrument letdown. Isn't that sort of circular? It doesn't actually say
when an instrument letdown is necessary.


--
Paul Tomblin http://xcski.com/blogs/pt/
"You must be smarter than this stick ---- to put a machine on the
Internet."

"Peter" wrote in message
...

Does that mean that, on an IFR flight, one is not allowed to descend
below the MOCA except on a published IAP?

One could read 175 as saying that if an official IAP is provided, it
must be used.


No, it means that unless otherwise authorized by the Administrator
nonmilitary aircraft of the United States operating under IFR are not
allowed to descend below the minimum IFR altitude when an instrument letdown
to a civil airport is necessary except on a published IAP.

"Paul Tomblin" wrote in message
...

It says "when an instrument letdown...is necessary" that you shall use an
instrument letdown. Isn't that sort of circular? It doesn't actually say
when an instrument letdown is necessary.


An instrument letdown would be necessary whenever there's no way to descend
without one. Already at the MIA and still in IMC? Visual, contact, or
radar approach not an option? Looks like an instrument letdown is
necessary.

"Roy Smith" wrote in message
...

It does more than suggest, it states it quite explicitly (for most of us,
neither of the exceptions are likely to apply):

"Unless otherwise authorized by the Administrator, when an instrument
letdown to a civil airport is necessary, each person operating an
aircraft, except a military aircraft of the United States, shall use a
standard instrument approach procedure prescribed for the airport in part
97 of this chapter."

So the next question, which I'll ask on Peter's behalf is...

Since Part 97 only prescribes approaches for airports within the US (and
presumably associated territories), how does an N-registered aircraft ever
fly an IAP in IMC outside the US?

Julian

"Peter" wrote in message
...

This could be any of MEA, MOCA, MRA?


It couldn't be an MRA. An MRA is simply the lowest altitude at which an
intersection can be determined and should always be above the MEA/MOCA.



Would the pilot be free to choose
the lowest?


The pilot would comply with his clearance.

"Julian Scarfe" wrote in message
...

So the next question, which I'll ask on Peter's behalf is...

Since Part 97 only prescribes approaches for airports within the US (and
presumably associated territories), how does an N-registered aircraft ever
fly an IAP in IMC outside the US?


Probably by being otherwise authorized by the Administrator.

"Julian Scarfe" wrote in message
...

So the next question, which I'll ask on Peter's behalf is...

Since Part 97 only prescribes approaches for airports within the US (and
presumably associated territories), how does an N-registered aircraft
ever fly an IAP in IMC outside the US?


"Steven P. McNicoll" wrote in message
.net...
Probably by being otherwise authorized by the Administrator.

So is there some sort of generic authorization, or is it authorized on a
case by case basis?

The latter seems unlikely. Do you really apply for such an authorization
every time you fly IFR to Canada?

Julian

"Julian Scarfe" wrote:

So the next question, which I'll ask on Peter's behalf is...

Since Part 97 only prescribes approaches for airports within the US (and
presumably associated territories), how does an N-registered aircraft ever
fly an IAP in IMC outside the US?

That's easy, this rule doesn't apply outside the US. Part 91.1 says:

"this part prescribes rules governing the operation of aircraft [...]
within the United States, including the waters within 3 nautical miles of
the U.S. coast."