Which is more important FAR-wise?

EdFred

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Maintaining cloud clearance, or maintaining appropriate cruise altitude for the direction of flight?

It got me thinking when I was flying home yesterday playing dodge 'em with some puffies, and had to temporarily fly a 2n+500 altitude while eastbound to go over a 2-3 mile wide bank of clouds. I wouldn't have even gotten to the next n+500 before I was past the cloud bank and would have been coming back down anyway.
 
Maintaining cloud clearance.
 
You wouldn't have been cruising, so in maneuvering flight, the hemispheric rule doesn't apply, does it?
 
Cloud clearances. Even if you are at the "wrong" VFR cruising altitude, as long as you maintain cloud clearance you should be able to maintain visual separation. Doesn't work the other way around.
 
You wouldn't have been cruising, so in maneuvering flight, the hemispheric rule doesn't apply, does it?

I guess the real question is, how long can you stay at an altitude before it is considered a cruise. And secondly, when manuevering around clouds, be prepared to see others at possibly "wrong" altitudes.
 
I don't think there's any hard and fast definition of how long you have to be at an altitude for it to be considered cruising flight, but if the clouds you're concerned about are large enough in extent for this to be a concern, maybe you could descend to 3000 agl or less, where the hemispheric rule doesn't apply.
 
I guess the real question is, how long can you stay at an altitude before it is considered a cruise.

Until either you hit someone, or until ATC says "WTF" and tries to bust you. Basically, as soon as the FAA notices, it will be considered cruise. ;)

And secondly, when manuevering around clouds, be prepared to see others at possibly "wrong" altitudes.

An excellent point. :yes:
 
I guess the real question is, how long can you stay at an altitude before it is considered a cruise.

My personal opinion on that is "as long as you are climbing/descending or considering doing so before needing to in order to land" you are not cruising long enough to require compliance with the hemispherical rule (which as explained by Richard Bach, only guarantees that all midair collisions above 3000 AGL will occur at angles less than 180 degrees).

And secondly, when manuevering around clouds, be prepared to see others at possibly "wrong" altitudes.
I'd say that most pilots are willing to climb and/or descend through holes too small to provide for the FAA mandated cloud avoidance distances. Virtually every pilot I've been with that passed through a scattered to broken deck did so without staying far enough away. I've also wondered how the FAA expects pilots to determine the distance from their airplanes to nearby clouds and I've never seen any sort of training to address this.
 
I've also wondered how the FAA expects pilots to determine the distance from their airplanes to nearby clouds and I've never seen any sort of training to address this.

It's just "by guess, and by golly," I guess. Maybe it's one of those skills that improves with experience.
 
Maybe it's one of those skills that improves with experience.
I doubt it. How many people can estimate 2000 feet away from some object on the ground with any accuracy let alone 2000 feet from something as indefinite as a cloud with no other reference points?
 
I doubt it. How many people can estimate 2000 feet away from some object on the ground with any accuracy let alone 2000 feet from something as indefinite as a cloud with no other reference points?

Fortunately it's just as difficult for the FAA to use their tape measures against us.
 
I doubt it. How many people can estimate 2000 feet away from some object on the ground with any accuracy let alone 2000 feet from something as indefinite as a cloud with no other reference points?
As I've always said, if an examiner asks how many feet you are from a cloud, s/he's testing your knowledge, not your depth perception.

In any event, while the 91.159 altitudes are significant in terms of keeping folks from head-on encounters, you've still got a good chance to see and avoid. OTOH, the cloud clearance rules are life-critical in terms of keeping an IFR plane coming out of a cloud from skewering a VFR plane passing by that cloud before anyone has a chance to detect, evaluate, and react.
 
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OTOH, the cloud clearance rules are life-critical in terms of keeping an IFR plane coming out of a cloud from skewering a VFR plane passing by that cloud before anyone has a chance to detect, evaluate, and react.
Visibility rules have this component to their reasoning too. They are not in effect solely to keep VFR pilots from getting lost or disoriented.
 
As I've always said, if an examiner asks how many feet you are from a cloud, s/he's testing your knowledge, not your depth perception.

Exactly.

Examiner: "How far are we below those clouds?"
(at 3000 MSL below an overcast sky in class E airspace)

Examinee: "At least 500 ft"[/quote]

In any event, while the 91.159 altitudes are significant in terms of keeping folks from head-on encounters, you've still got a good chance to see and avoid. OTOH, the cloud clearance rules are life-critical in terms of keeping an IFR plane coming out of a cloud from skewering a VFR plane passing by that cloud before anyone has a chance to detect, evaluate, and react.[/quote]

Except, of course when it most likely matters most e.g. coming out of a 1000 AGL cloud deck (IFR) flying into a class G airport with a NORDO in the pattern skimming the cloud bases.

-lance
 
Except, of course when it most likely matters most e.g. coming out of a 1000 AGL cloud deck (IFR) flying into a class G airport with a NORDO in the pattern skimming the cloud bases.
Can't do much with someone who's breaking the rules by being that close to the clouds in E-space (since it's 1000 AGL at an airport with an instrument approach) -- should be no higher than 700 AGL. And below 700 AGL, he's probably violating 91.119 while flying the pattern.
 
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