Gary Drescher wrote:

"Steven P. McNicoll" wrote in message
ink.net...
You're responsible for any bust. If following the instruction meant
entering the Class B airspace I'd respond to it with "verify I'm cleared
into Class B airspace." If the controller replies with "Negative" I'd
inform
him I was turning to avoid Class B airspace. Pilots are required to abide
by the FARs regardless of any ATC instruction.

I don't dispute that the FAA takes that position. But the FARs themselves
are contradictory on that point. FAR 91.123b requires obeying ATC
instructions, except if an emergency requires otherwise. There's no stated
exception for non-emergency violations of the regs. If the tower says
"Continue downwind, I'll call your base" and then hasn't gotten back to you
two minutes later when you're about to enter Class B, and if the frequency
is too crowded for you to call, then the only way to avoid busting Class B
may be to violate 91.123b.

--Gary

If frequency conjestion creates a sustained inability to request either a Class
B clearance to enter the imminent Class B airspace or a new instruction to avoid
the Class B, you have an emergency brewing. An emergency is not limited to the
aircraft having a mechanical or similar such problem. Violating Class B
airspace has unknown ramifactions, such as perhaps approach control seeing the
intrustion and declaring an emergency on your flight because of loss of
separation, etc., etc.

So, in that light, use of your emergency authority under 91.03 (a) and (b) would
be considered appropriate. Having said that, whatever action you have to take
to avoid the Class B should be reasonable and prudent so as to not unnecessarily
create an unsafe condition for the local controller working your flight.

Sometimes, operating in conjested airspace involves juggling several balls at
the same time. Operating IFR actually makes it all more straight-forward
because the entire concept of Class B operates in favor of IFR operations.

When Class B (TCAs) first was proposed in this country there were a lot of
advocates that wanted to make that airspace Class A. But, other interests
strongly opposed going that far.