Airspeed Restrictions

[minitour]

"There's no speed restriction at all in class B airspace."
-mini

Seems to me operations in Class B fall under the speed restrictions of 91.117(a). There have been exceptions to the rule(remember the Houston departures?). I has been knowed too bee rong. Pleeze corekt me if i are now.

Not that I know of any US Class B airspace out there that is entirely above 10,000' MSL, but if there was such airspace, there would be no 250 knot speed restriction.

The restriction isn't being in Class B, it's being below 10,000'.

I know it's picking nits, but....

-mini

 

[NoahWerka]

Granted. Above 10k there is no speed restriction in Class B airspace.

 

[minitour]

Granted. Above 10k there is no speed restriction in Class B airspace.

I'm sure it's one of those "tomato - tomahto" things. Like the whole "first class, second class, third class medical" thing. You know...how some people teach it so students think it magically morphs from I to II on day 1 of month 7...or from II to III on day one of month 13...

I'm just in a nit-picky moooood....been talking to the wife and she makes me b*tchy.

-mini

 

[lawfly]

There is no speed RESTRICTION that is specific and unique to oeprations IN Class B (except for VFR corridors, discusssed below). Below 10,000, the 10/250 rule applies, regardless of class of airspace. There is the 200k rule for operations underlying (but not in) Class B airspace. In short, there is no speed restriction which derives solely from operation within Class B airsapce (except for the 200k restriction in a "VFR corridor designated through...Class B airspace"---91.117(c)). Indeed, Class B airsapce is NOT subject to certain restrictions found elsewhere, such as the 200 knot Class C/D primary airport speed restriction. (91.117(b)). So, the VFR corridor speed restriction appears to be the only restriction deriving from and specific to (certain VFR) operation within (designated portions of) Class B airspace.
In any event, the original post was about regulatory airspeed restrictions above 10,000.

 

[MauleSkinner]

§ 91.117 Aircraft speed.

(c) No person may operate an aircraft in the airspace underlying a Class B airspace area designated for an airport or in a VFR corridor designated through such a Class B airspace area, at an indicated airspeed of more than 200 knots (230 mph).

So...is it the "Class B" that's designated for an airport, or is it the "airspace underlying" that's designated for an airport?

 

[charter dog]

Not that I know of any US Class B airspace out there that is entirely above 10,000' MSL, but if there was such airspace, there would be no 250 knot speed restriction.

The restriction isn't being in Class B, it's being below 10,000'.

I know it's picking nits, but....

-mini

Right!

Denver is the one I was thinking of. I believe the DEN class B tops out at 12,000' msl. Since there is no speed limit in class B airspace per se, this would be one class B area where there is no 250 KIAS restriction, at least within that portion of the airspace at or above 10,000' msl. The class Bs that top out at 10,000' msl have the restriction in place by virtue of the 250 KIAS below 10,000' msl rule. (Houston experiment aside)

Good call mini!

Best,

 

[rballty]

I believe there is a max airspeed of .83 Mach in RVSM airspace, from FL290 to FL410.

 

[minitour]

So...is it the "Class B" that's designated for an airport, or is it the "airspace underlying" that's designated for an airport?

Class B Airspace Designated for an Airport (ie the "ORD Class B" is set up for ORD). If you are under the shelf of the Class B airspace you're limited to 200KIAS.

Class B Airspace is set up for the busiest airports (one of the most restrictive airspaces) so ATC doesn't have to worry about the bugsmasher going through when they don't want 'em there, etc. So it is airspace designated for an airport (the ORD class B is set up for ORD).

-mini

 

[rtmcfi]

I believe there is a max airspeed of .83 Mach in RVSM airspace, from FL290 to FL410.

First time I have heard that one..... I think you should examine your beliefs!

 

[MauleSkinner]

Class B Airspace Designated for an Airport (ie the "ORD Class B" is set up for ORD). If you are under the shelf of the Class B airspace you're limited to 200KIAS.

Class B Airspace is set up for the busiest airports (one of the most restrictive airspaces) so ATC doesn't have to worry about the bugsmasher going through when they don't want 'em there, etc. So it is airspace designated for an airport (the ORD class B is set up for ORD).

-mini

Why do they have to say "designated for an airport"? Seems pretty redundant, since Class B is ONLY designated for an airport.

And why, then, don't they reference Class C or Class D that's "designated for an airport"? These simply say in Class C or D airspace within 4 miles of the primary airport.

Fly safe!

David