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Question about airspeed in class B?

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Sir Humpalot

Well-known member
Joined
Aug 30, 2002
Posts
142
I understand that if one is below 10000ft, the limiting airspeed is not greater than 250knots. If a class B airspace extends over 10000ft (ie DEN), does the airspeed still have to be 250 or less?

The logic states that it is still in class Bravo and so the airspeed has to be less than 250 but i just wanted someones input on this one.

Any help appreciated.
 
Aircraft speed.

(a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m.p.h.).
(b) Unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles of the primary airport of a Class C or Class D airspace area at an indicated airspeed of more than 200 knots (230 mph). This paragraph (b) does not apply to any operations within a Class B airspace area. Such operations shall comply with paragraph (a) of this section.
(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).
(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.

No special speed restrictions in Class B.
 
Are you talking about being beneath Class B or inside Class B? He just quoted you an FAR.
 
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liv'n_on_credit said:
The last post is incorrect. Everyone knows that there is a 250 knot speed restriction inside class B. Yes, even though it is above 10,000 you are still in class B airspace (like at DEN), therefore you still limited to 250KIAS.
That's not quite correct. There are exceptions...

This very issue was discussed on one of the NBAA forums that I participate in awhile back. (It's only been that last few years that this has even come up for us bizjet types, we haven't had any aircraft where this was even an issue.) Several airline pilots chimed in and contributed to the discussion. The following quote was typical of what they all said: "...If your weight nets a required clean min speed above 250 kts below 10,000' you can accelerate to that speed, period. There is no requirement that you fly with flaps/slats out so you can stay below 250 or 200 kts below the lateral limits of Class B, etc." The bottom line is that the intent of 14 CFR 91.117 is not to force heavy jets to leave flaps/slats out to climb. They are expected to clean up and fly at clean MMS until 10000'.

For us, the issue was what about when we operate out of one of the airports that are underneath the lateral limits of CBA? There is a 200 KIAS limit in that airspace. The Gulfstream G-200, at higher takeoff weights, requires airspeeds of around 220 KIAS to retract the slats and Krueger flaps. Although I believed what the airline pilots were telling us, I also wanted to avoid the opportunity of having to spend "quality time" at the local FSDO so I contacted a good friend of mine who is an FAA inspector. I asked him the following specific question: "...is it necessary to maintain a configuration (slats and Kruger flaps deployed) that will allow the aircraft to comply with the 200 KIAS speed limit when operating beneath the lateral limits of Class B airspace or is it acceptable to fly the aircraft in the "clean" configuration even though the minimum safe airspeed in the clean configuration is above the 200 KIAS limit?" He refered the question to another inspector at another office, who sent me the following reply:

"...The FAR's do not prohibit that operation. Now that I have said that let me explain the finer points about working with ATC and the FAA.
1. If you are at a low altitude and exceed 200 or 250 there is a record made by ATC and ATC may question you. However your flight in question will end up as an
investigation at the FSDO. When you are contacted regarding the "possible fracture" of 91.117 and you tell them what you told me it will probably be closed with no action.

2. You have 2 choices (1) configure the airplane to maintain the speed limits or (2) fly clean at the higher speed.

3. If you maintain speed limits and configure the airplane to do so, no problem end of subject.

4. If you clean the airplane up and accelerate to the speed required be absolutely positive you tell ATC on each frequency you operate on the reasons for exceeding the speed limits while in the airspace discussed in 91.117. Remember ATC spaces aircraft distances based on speed. This should preclude a FSDO investigation.

If you read 91.117(d) it does not specify the aircraft configuration. All it says is "...any particular operation..."

The decision is yours. Hope this helps."

There are those who think that 91.117 (a) authorizes individual air traffic controllers to authorize deviations from the rule. NOT! ATC is NOT the "Administrator" and controllers can not authorize deviations. There is an ongoing "test" at IAH where the Administrator has authorized increased speed operations and controllers can and do ask you to pick up the speed.

There are some other exemptions, such as operational necessity & emergencies that allow you to deviate. Personally, I've deviated from the rule many times, back when I was a Life Flight pilot flying Citations and MU-2 air ambulances. When the flight nurse or physician told us to "step on it" that's exactly what we did. We just told ATC that we needed to keep our speed up. We'd keep the speed at the barber pole until it was necessary to start slowing down for landing. All the FSDO guys wanted from us was the usual deviation letter. I bet I filled a couple of dozen of those forms over a 3-year period.

Hope this helps clarify things.

Lead Sled
 
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liv'n_on_credit said:
The last post is incorrect. Everyone knows that there is a 250 knot speed restriction inside class B.

Yes, even though it is above 10,000 you are still in class B airspace (like at DEN), therefore you still limited to 250KIAS.
Do you have the reference for this? I have tried unsuccessfully to find a regulatory reference for this. There used to be a restriction but I haven't seen it for a couple of years.
 
igneous guy has it right...

250 below 10k...no special restrictions for class b...

Class B is (supposed to be) set up for large traffic volume airports and is (supposed to be) from the surface up to 10k msl... obviously some are not...it just depends on the instrument approach procedures associated with the particular Class B airspace regarding how the airspace is set up...

for example...PIT is Class B from SFC up to 8,000...the airport elevatipon is 1204 so would it make sense to have another 9,000' of airspace for them? No 7,000' does just fine for the instrument procedures that are set up into PIT...

now for DEN...the elevation is 5431' so for them to go to 10,000' MSL wouldn't make sense either as that would only be another 4569' AGL...not very much space to set up instrument approaches with that much traffic coming in...so the set up their airspace to go higher for them (not sure on their cieling)

Its all in 91.117 (which was quoted already)...just like it says Class B airspace doesn't apply and aircraft are to abide by paragraph (a) [250 below 10,000 unless otherwise authorized by the administrator]...*edit* I'm assuming its in there like this so a big ol heavy doesn't have to stay at 200KIAS on departure until clear of that initial "surface area' of the airspace...thats just my assumption though

-mini
 
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Correction

NewBlue said:
There used to be a restriction but I haven't seen it for a couple of years.
I stand corrected. I guess I need to update my books!

When I took my ATP written, there was a question in there about being in class B airspace and what the speed restriction was, and the answer was 250 knots. But on second thought, I think the airplane in the question was also below 10,000 feet.

After reading through the current FAR's, I agree with the last post.
 
Wrong

liv'n_on_credit said:
The last post is incorrect. Everyone knows that there is a 250 knot speed restriction inside class B.

Yes, even though it is above 10,000 you are still in class B airspace (like at DEN), therefore you still limited to 250KIAS.
FAR 91.117 states 10,000' not Class B! Lots of people incorrectly assume that since most Class B's go up to 10,000' that's the reason for the speed limit.

In places like Denver and Atlanta it is common practice to accelerate to above 250 once above 10,000 and still within the Class B.

Here's an excerpt from a legal opinion dated 10/3/1993: "On September 16, 1993, the Airspace Reclassification Final Rule became effective. Under the provisions of this rule, TCA's are reclassified as Class B airspace areas. FAR Sec. 91.117(a) now states, "unless otherwise authorized by the Administrator (or by ATC in the case of operations in Class A or Class B airspace), no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 mph)." FAR Sec. 91.117(b) now states, "unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles the primary airport of a Class C or Class D airport at an indicated airspeed of more than 200 knots (230 mph)." Under this regulatory scheme, it is now clear that the pilot operating in a Class B airspace area at and above 10,000 feet MSL is not subject to a 250 knot speed limitation."
 

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