IFR Landing Minimums for Part 91 Operations
Christopher Pettus
non-commercial Part 91 operations. The relevant section of the FARs
states ...
91.175 TAKEOFF AND LANDING UNDER IFR
(c) Operation below DH or MDA. Where a DH or MDA is applicable,
no pilot may operate an aircraft, except a military aircraft of
the United States, at any airport below the authorized MDA or
continue an approach below the authorized DH unless --
(2) The flight visibility is not less than the
visibility prescribed in the standard instrument
approach procedure being used; [...]
[and, redundantly]
(d) Landing. No pilot operating an aircraft, except a military
aircraft of the United States, may land that aircraft when the
flight visibility is less than the visibility prescribed in the
standard instrument approach procedure being used.
Now, in both cases, the term used is "flight visibility." Does this
mean that if the ATIS is reporting 1/4F, and the minimums for the
approach are 1/2F, can I still land if I (as PIC) feel the flight
visibility is 1/2 or more? Or is this ATIS assumed to be correct for
this purpose?
--
-- Christophe
"Oh, so you're going to kill me! What a finely-tuned response to the
situation!"
Steven Brecher brecher@btr.com
the FAR 91.175 prohibition against operating below DH or MDA, or landing,
when the flight visibility is less than prescribed in the approach
procedure:
> Now, in both cases, the term used is "flight visibility." Does this mean
> that if the ATIS is reporting 1/4F, and the minimums for the approach are
> [1/2], can I still land if I (as PIC) feel the flight visibility is 1/2 or
> more? Or is this ATIS assumed to be correct for this purpose?
"Flight visibility" is defined in FAR 1 as being from the cockpit of an
aircraft in flight. So with respect to FAR part 91, yes, you are the
judge of flight visibility.
Part 135, which applies to people who get other people to pay for their
flying, specifies reported conditions as the criterion.
--
bre...@btr.com (Steve Brecher)
Rick Reed
Now, in both cases, the term used is "flight visibility." Does this
mean that if the ATIS is reporting 1/4F, and the minimums for the
approach are 1/2F, can I still land if I (as PIC) feel the flight
visibility is 1/2 or more? Or is this ATIS assumed to be correct for
this purpose?
Under Part 91, it's the pilot's call, though that means you must actually
have the required visibility, not just see enough to land. So if the
controller queries you after an ILS with RVR 2400 minimums, you should be
able to say "I had the touchdown bars in sight at the middle marker"
("the wind must've blown a hole in the fog").
Seriously though, since the reported visibility is usually from the tower,
it's possible for the conditions to be better (or worse) at the approach
end of the runway, less likely if the RVR's reported though still possible
since it measures the vis in the touchdown zone not the "approach zone".
Rr
RVR - Runway Visual Range
Eric Myers
>mean that if the ATIS is reporting 1/4F, and the minimums for the
>approach are 1/2F, can I still land if I (as PIC) feel the flight
>visibility is 1/2 or more?
Yes. The it's the "flight" visibility, not the tower or runway
visibility. You make the call.
Of course if it's that close you have my respect... or condolences.
--
Eric Myers "If God had intended for man to fly
He would have given us the brains to build airplanes."
Center for Relativity, Department of Physics, University of Texas at Austin
my...@emx.utexas.edu | my...@utaphy.bitnet | my...@ut-emx.UUCP
Matthew Waugh
>non-commercial Part 91 operations. The relevant section of the FARs
>states ...
>
>
>Now, in both cases, the term used is "flight visibility." Does this
>mean that if the ATIS is reporting 1/4F, and the minimums for the
>approach are 1/2F, can I still land if I (as PIC) feel the flight
>visibility is 1/2 or more? Or is this ATIS assumed to be correct for
>this purpose?
You are correct. Let me know how the FAA and NTSB appeal goes. :-)
As a part 91 operator you need the flight visibility to land, and if you
have it you can land. At that point it's your word against the trained
weather observer in the tower, and possibly the RVR equipment if it's
around. If they went after your ticket and you didn't have something
other than your honest face to back up your visibility estimate I
suspect you'd lose, and I believe people have lost on such occassions,
but the regs. say you'd be OK.
Mat
Matthew Waugh wa...@dg-rtp.dg.com
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