VFR WX Minimums - Distance from Clouds

HPNPilot1200

HPNPilot1200

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Jason
I have a question regarding "Distance from Clouds" in FAR §91.155 - Basic VFR Wx minimums.

If you look at class E airspace below 10,000 feet, the FARs specify you must operate the aircraft (in Class E airspace below 10,000) [under VFR] 500 feet below, 1,000 feet above and 2,000 feet horizontally from clouds.

If you look at class B airspace, the FARs specify you must operate the aircraft (in Class B airspace) [under VFR] "Clear of Clouds."

Which is more restrictive? What does "clear of clouds" really mean?

If I interpreted the FARs correctly, "clear of clouds" means keeping your aircraft clear of any/all clouds, but you can get as close to them as you'd like, as long as you remain clear (not in) of them. From that conclusion, I would think that class B Wx minimums (in regards to distance from clouds) are less restrictive.

Is that correct? If not, please specify why.

Thanks,
Jason
 
you are correct jason. the distance requirements in class E are in case that IFR guy pops out of a cloud, you have some distance (time) to react and miss each other. In B space, VFR and IFR are under positive control, so you can go close to clouds. Also alleviates controller headaches on scattered or few days when all the VFR guys would need diversions to maintain cloud clearance
 
Frequently in class E airspace there is no radar coverage. The cloud clearance regs are intended to keep VFR aircraft clear of potential IFR traffic, giving both pilots enough time to react if the IFR airplane comes bouncing out of the clouds near the VFR airplane.

In class B airspace everything flying is supposed to be in radar contact, so the controllers can keep appropriate separation. The VFR pilot just needs to remain VFR - that is, remain clear of clouds.

I always wondered how I was supposed to know how far 2,000' lateral separation is. ???

Chip
 
You don't keep that 2k' tape in the Extra?

gibbons said:
I always wondered how I was supposed to know how far 2,000' lateral separation is. ???

Chip
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Steve said:
You don't keep that 2k' tape in the Extra?
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Yeah, but when you put it out horizontally, it inevitably bends someplace in the middle and takes out a building.
 
gibbons said:
I always wondered how I was supposed to know how far 2,000' lateral separation is. ???
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On climb out for my PP-ASEL checkride last year, the ceiling was being reported as 3000' (AGL) and broken. Approaching 3000' (MSL) the clouds sure looked lower and my DPE asked "How far below the clouds are we?" - I just smiled and said more than 500 ft and he smiled back and said good answer. (For the record "ground" is 918' MSL).
 
inav8r said:
On climb out for my PP-ASEL checkride last year, the ceiling was being reported as 3000' (AGL) and broken. Approaching 3000' (MSL) the clouds sure looked lower and my DPE asked "How far below the clouds are we?" - I just smiled and said more than 500 ft and he smiled back and said good answer. (For the record "ground" is 918' MSL).
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Thats great.
 
HPNPilot1200 said:
Which is more restrictive? What does "clear of clouds" really mean?
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As stated earlier, you're supposed to be in radar contact. Also, it's understood that you'll be in radio contact as well. If anyone's in the clouds around you, they'll let you know. :)
 
gibbons said:
...
I always wondered how I was supposed to know how far 2,000' lateral separation is.

???
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In the midwest, that's easier to judge. 2000 feet is less than half of one the squares that God divided the ground with. Those squares are a mile.

I just err on the side of caution.
 
yep that is nice mike. on my last cross country home with the gf, i was explaining to her how god divided the heartland into a one mile square grid. "well what about the interstate?"
"god didnt build the interstate"
 
MSmith said:
Yeah, but when you put it out horizontally, it inevitably bends someplace in the middle and takes out a building.
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No problem. He's got one of those aerobatic thingies. There use to be an airshow group that would tie a cord between planes (with a tension release slip knot of some kind) and do their routine.
Just tie the cord between him and Diana and let them go play in Class B somewhere for a while and they'll be able to sort out what 2000ft looks like.
 
AirBaker said:
As stated earlier, you're supposed to be in radar contact. Also, it's understood that you'll be in radio contact as well. If anyone's in the clouds around you, they'll let you know. :)
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It's really got nothing to do with RADAR although RADAR really helps. Class B is positive control airspace so everyone legally inside is being separated by ATC (RADAR or not). In Class E space (with or without RADAR coverage) ATC may only provide separation between IFR aircraft, hence the more restrictive requirements for VFR traffic.
 
lancefisher said:
It's really got nothing to do with RADAR although RADAR really helps. Class B is positive control airspace so everyone legally inside is being separated by ATC (RADAR or not).
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I suspect that if the radar was down, there wouldn't be too many VFR aircraft allowed in a Class B area -- like probably none.
 
Ron Levy said:
I suspect that if the radar was down, there wouldn't be too many VFR aircraft allowed in a Class B area -- like probably none.
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Hmmm... The scenario that came into my mind was this: It's a regular day in a class B other than Chicago (ie they actually let some VFR aircraft in) and all of the TRACON's radios go completely, utterly dead.

The IFR pilots have been trained in lost comm procedures and will go about their business. What about the VFR's? Do the controllers give them instructions such that they won't be a problem when they enter the B-space?
 
lancefisher said:
It's really got nothing to do with RADAR although RADAR really helps. Class B is positive control airspace so everyone legally inside is being separated by ATC (RADAR or not). In Class E space (with or without RADAR coverage) ATC may only provide separation between IFR aircraft, hence the more restrictive requirements for VFR traffic.
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Yeah, I know it wasn't quite right. (I'm sure its not written that way in the FARs). However, as Ron said, it would be interesting to see what goes on without Radar. :) A year or so ago when the fires came through SoCal, TRACON was basically out. You couldn't get close to the airspace down there with the smoke and those controller types not knowing where you were.

I'd have to go back and look up the specifics, but flights to LA were grounded and there were people over at Reid Hillview looking for charters from anyone.
 
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flyingcheesehead said:
Hmmm... The scenario that came into my mind was this: It's a regular day in a class B other than Chicago (ie they actually let some VFR aircraft in) and all of the TRACON's radios go completely, utterly dead. The IFR pilots have been trained in lost comm procedures and will go about their business. What about the VFR's? Do the controllers give them instructions such that they won't be a problem when they enter the B-space?
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Nothing specific. And there's no regulation to cover this event, so common sense (follow last instruction and then exit the B-space ASAPrac, either up, down, or laterally) would be the order of the day. But again, even the VFR pilot should be smart enough to listen to the chatter of the other planes on freq, pretend it's just like the CTAF at Moosebutt Muni, and go with the flow -- just with a few more, bigger, faster planes around (fortunately flown by pros).
 
Ron Levy said:
Nothing specific. And there's no regulation to cover this event, so common sense (follow last instruction and then exit the B-space ASAPrac, either up, down, or laterally) would be the order of the day.
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Yup. However, what if exiting the B meant busting VFR mins? Last summer on my way into Houston, I was glad they let me into the B, because visibilty was getting rather borderline. Of course, lost comm for the B would pretty much mean you're no safer in than out anyway, so declare and land at the nearest practical field outside the B.

But again, even the VFR pilot should be smart enough to listen to the chatter of the other planes on freq, pretend it's just like the CTAF at Moosebutt Muni, and go with the flow
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Amen to that. And they should have their current TAC chart and stay out of the way of the approach/departure corridors too...
 
flyingcheesehead said:
Yup. However, what if exiting the B meant busting VFR mins?
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At that point, 14 CFR 91.3(b) applies -- ya do what ya gotta do to get on the ground safely, and worry about the rules later.
 
AirBaker said:
However, as Ron said, it would be interesting to see what goes on without Radar.
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It all depends...

On my last dual XC flight for the instrument ticket we were enroute to Dullas...radar in the Washington area went down...no problems...everyone had to do the manditory and some additional position reporting.

My first solo flight on an instrument flight plan was in marginal conditions (due to summer haze) returning to the Philadelphia area (PNE) from the Hartford area. An AT&T telcom problem knocked out the radar in the New York area. I was just inside the Class B (TCA at the time) when it happened and was given an intersection hold with an expect further clearance of 120 minutes.:eek:

Len
 
Len Lanetti said:
I was just inside the Class B (TCA at the time) when it happened and was given an intersection hold with an expect further clearance of 120 minutes.:eek:

Len
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ICK! I'd really hate to do the 30 times around in a hold.
 
TMetzinger said:
How quickly did you say "unable", and what did you end up doing?
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If one said "unable" in that situation, ATC's probably response would be something like, "Say intentions -- diverting to BDR or declaring an emergency?" In that sort of situation, they really can't stand "unable" without a request that will get you out of their system.
 
Yeah - I should have been clearer. The correct response (assuming you don't have an extra two hours of fuel on board) would have been either to reply "Roger -Unable 120 min due to fuel, we'll be back to you with an alternate plan" or "Unable, request clearance to XXX (and maybe via YYY if you're thinking that far ahead)".
 
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