Class Bravo Operations

Chrisgoesflying

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Chrisgoesflying
Now that I'm based inside a busy class Bravo airspace, I had a situation come up, wondering on how this would be handled. For context, I only recently got my plane ADS-B compliant so I'm new to flying in busy B airspace in the U.S. In Canada, I didn't need ADS-B so I flew through Toronto airspace frequently, hence radio coms are fine with me, however, Toronto controllers usually gave me such low altitudes that the following scenario usually would never apply, but it did come up in DFW class B recently.

Situation: I was flying at 4,500 ft. and was cleared into the Bravo at 4,500 ft. staying on present heading and altitude. As I made my way through the Bravo, I saw clouds at my altitude and present heading. Not being instrument rated, I asked for lower and they cleared me down to 3,500 which was sufficient so all good. However, another plane like 10 minutes behind me had the same request. He was also at 4,500, asked for lower due to clouds and at first, the controller didn't get back to him for a long time (frequency was busy) and then when they did get back to him, they just told him to stay at 4,500.

My questions:

1. In that scenario above, what is one to do if there are clouds in front of you, you are assigned a certain altitude, asked for lower and the controllers don't get back to you?

2. Same scenario, what if the controller does get back to you but tells you to remain at the altitude where the clouds are?
 
Class Bravo, remain clear of clouds while VFR.

You must maintain VMC conditions, that’s on you the pilot, therefore you shall deviate to maintain VMC.

For me, I inform my intentions, wait a few seconds, then act. If ATC advises otherwise, you say “unable” and then advise the reason, unable to maintain current altitude due to clouds ahead. You can provide alternatives if you want, of course you can see traffic on your foreflight so you can make a plan too.

I once was cleared into the Bravo, and when switching controllers, the new controller said remain outside of the Bravo and I responded unable due to clouds, plus I was already cleared into the Bravo (transitioned a Delta thus talking to that airports tower then back to approach when passing through).
 
Class Bravo, remain clear of clouds while VFR.

You must maintain VMC conditions, that’s on you the pilot, therefore you shall deviate to maintain VMC.

For me, I inform my intentions, wait a few seconds, then act. If ATC advises otherwise, you say “unable” and then advise the reason, unable to maintain current altitude due to clouds ahead. You can provide alternatives if you want, of course you can see traffic on your foreflight so you can make a plan too.

I once was cleared into the Bravo, and when switching controllers, the new controller said remain outside of the Bravo and I responded unable due to clouds, plus I was already cleared into the Bravo (transitioned a Delta thus talking to that airports tower then back to approach when passing through).
This. Just make small deviations around the clouds to remain clear in Class B. If this is an actual cloud ceiling/deck then I would be requesting lower, or advising ATC that I would be descending to whatever altitude keeps me clear.
 
Also try to be aware of the arrival/departure patterns from the Bravo airport. If you have the choice of deviating up/down/left/right pick the one that seems least likely to cause a conflict with arriving or departing commercial traffic.
 
Okay, so seems like when VFR in Bravo, I can deviate (after advising ATC) in order to remain clear of clouds without getting the dreaded "possible pilot deviation, here's a number to call for ya."

I looked at the arrival paths and also looked at flightaware prior to the flight and it was busy in the Bravo so I originally intended to stay south of it until south of the destination and then request clearance into the Bravo for just a brief 5 minute flight to the destination - I told FW Center of my intentions. But, when they handed me off to Regional Approach just east of the Bravo (when I was just about to turn south to stay out of it), Regional Approach gave me "cleared into the bravo, direct Spinks" so I thought why not get a nice view of Dallas and Fort Worth flying "home" for the first time :)
 
when VFR in Bravo, deviate (after advising ATC) in order to remain clear of clouds without getting … "possible pilot deviation,”
Consider “after advising ATC” vs. “after obtaining an ATC clearance (to descend, turn, etc)”

For class B, is there a regulation which permits deviation from assigned altitude/heading (for weather avoidance), absent an amended clearance? (other than emergency authority)

If a VFR pilot descends (to avoid IMC), without a clearance, and causes a conflict, can “possible pilot deviation” be expected?
Even without conflicting traffic, after a deviation in Positive Control airspace, might FSDO be interested in a discussion, for example to review pre-flight planning (for weather)?

If it helps ….
In congested (B), consider airspace constraints (threats): traffic and weather.
Traffic
Class B Tracon manages separation for both IFR and VFR traffic.
VFR aircraft remain under positive control and absent an amended clearance, comply with assigned altitude/heading.

Weather
VFR aircraft in class B must remain clear of clouds.
Consider threats:
-(*)radio congestion precludes request for lower, or heading change
-traffic precludes clearance for descent. ATC: “Unable lower due to traffic. Say intentions.”
To avoid IMC, plan for alternative requests: heading change, and if that’s also unavailable, request 180 turn for weather avoidance.

In congested airspace, VFR pilots might avoid challenging constraints by mitigating threats.

For weather:
-(*)CAVU removes IMC threat; request bravo clearance and expect assigned altitude will remain clear of clouds.
-For low clouds, route avoiding class B

Are there other ways to avoid potential for being caught between a rock and a hard place?
 
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I've been in this situation. What I did is on my req for altitude, add "for VMC" at the end of your request. That lets the controller know you can't stay on the vector and alt currently running. The controller give me a left turn, and I said "unable, not VMC". Then followed it up finally with me telling them I'm going to do a course reversal and please advise. They replied to reverse course, then gave me a vector to another exit from the class B that worked. I was at 3000 and wanted 2000, but that was going to interfere with arrivals. They wanted me out of the B as much as I wanted out of there. Once out of the class B, but still on FF I then advised "I'm descending to 2400 for VMC", and there isn't anything they can do about it.
 
Okay, so seems like when VFR in Bravo, I can deviate (after advising ATC) in order to remain clear of clouds without getting the dreaded "possible pilot deviation, here's a number to call for ya."

I looked at the arrival paths and also looked at flightaware prior to the flight and it was busy in the Bravo so I originally intended to stay south of it until south of the destination and then request clearance into the Bravo for just a brief 5 minute flight to the destination - I told FW Center of my intentions. But, when they handed me off to Regional Approach just east of the Bravo (when I was just about to turn south to stay out of it), Regional Approach gave me "cleared into the bravo, direct Spinks" so I thought why not get a nice view of Dallas and Fort Worth flying "home" for the first time :)
I wouldn't just tell them you're deviating from your assigned altitude, although regulations do allow you to do that to avoid flying into the clouds. What I would do is let them know that you need to avoid a cloud in front of you to maintain VFR, and if they tell you to keep flying straight ahead or just don't respond, then you tell them, "Deviating x* left to remain VFR." Try not to cause a loss of separation when you do that....

If you're on Facebook, join the North Texas Aviators group. In addition to pilots, there are also some local controllers in there.
 
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First, understand the rules you are operating.

A. The Class B airspace VFR weather minimums are 3 sm and clear of clouds. (91.155(a)).
B. You are required to receive a clearance to operate in Class B. 91.131(a)(1).
C. You are required to adhere to that clearance 91.123(a))
D. Each pilot in command who, in an emergency, or in response to a traffic alert and collision avoidance system resolution advisory, deviates from an ATC clearance or instruction shall notify ATC of that deviation as soon as possible. (91.123(c)).

A typical Class B VFR clearance includes the instruction to remain VFR + a heading + an altitude. Something has to give if you can’t remain VFR. And why controllers don’t like to clear VFR aircraft into the Bravo.
 
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I think the OP is 'under' not in the class B. I used to be based under as well. I made a point to not call, and not try to get clearance into the B, just because it's fairly easy to get a deviation. I've heard other pilots in the B get a request to call this number, and I might burn an extra 3 gal going around the inner ring, and I'll gladly pay that extra gas for the option not to talk to or take vectors/altitudes from the B. It would be extremely rare for a GA pilot to 'need' to enter the class B, but it happens sometimes. Just not to me.
 
@Chrisgoesflying there are several of us near you here in the Metroplex. If you ever feel like you want to fly with someone to get familiar with the area, just reach out to one of us. I fly complex photography missions in the Bravo every week and have a working relationship with ATC.

1. If you understand the airspace and the system, it's really pretty good.
2. Keep in mind that cardinal altitudes like 3000, 3500, etc... are best because they allow the controllers to push more traffic through an area, but I've been given 2200, 2400, and all kinds of altitudes at times. If you can't maintain clear of clouds at 4500, you could succinctly advise them, "Approach NXXXNC unable to maintain 4500 for clouds, request 4200 or lower for cloud clearance" or something like that. They aren't going to force you to go into the clouds.
3. Usually, you don't want to bust even 100' or 200' of an assigned altitude in the Bravo, but if you have to fly 100' lower to avoid the clouds and stay legal, do it. Remember, you are PIC and responsible. Also, don't abuse this, but if you can't get a word in edgewise for an extended period of time, hit your IDNT button and they'll know you are trying to say something or get their attention.
4. Using flight following is usually a good thing since everyone is playing together unless you are in a peak time when the area is so saturated that the controllers are really really busy. I've been stuck up near Plano over a photo target for 15 minutes unable to get to my next target for the volume of radio traffic. As long as you can tell the frequencies aren't too busy, use the help. It generally improves separation.
 
This was actually part of my PPL oral (which was under the DFW bravo shelf actually). What do you do if you can’t stay VFR but you’re in the bravo? “Unable” and tell them what you’re doing, but just do enough to stay clear of clouds. Bravo clearance doesnt give you clearance to operate in IMC without a clearance.
 
First, understand the rules you are operating.

A. The Class B airspace VFR weather minimums are 3 sm and clear of clouds. (91.155(a)).
B. You are required to receive a clearance to operate in Class B. 91.131(a)(1).
C. You are required to adhere to that clearance 91.123(a))
D. Each pilot in command who, in an emergency, or in response to a traffic alert and collision avoidance system resolution advisory, deviates from an ATC clearance or instruction shall notify ATC of that deviation as soon as possible. (91.123(c)).

A typical Class B VFR clearance includes the instruction to remain VFR + a heading + an altitude. Something has to give if you can’t remain VFR. And why controllers don’t like to clear VFR aircraft into the Bravo.
The only airport I have issues with the Bravo airspace entry is Ohare. Others have been very accommodating. If we are experiencing weather then so are others.
 
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