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Driver170

SID Speed Rest.

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The 250 below 10,000' is a regulation.  The SID restrictions are ATC procedural.  ATC has the authority to cancel or modify procedural restrictions, but not regulatory restrictions.

 

jetjerry 

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Could that differ between Europe and USA? I've always understood that ATC in Europe can approve high speed below FL100 in Class A-D airspace. Listening to Dutch ATC, I often hear controllers instruct flights "high speed approved".

 

Edit: probably can (partially) answer my own question now. According to the Dutch AIP, there are no speed restrictions for IFR flights in class A, B, and C airspace. Any restriction in that airspace is procedural.


Marc ter Heide

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The 250 below 10,000' is a regulation.

 

Sure, it is routine to see heavies exceeding that. Houston has a NOTAM setting the limit to 280 full time... not sure where you are getting your information but I wouldn't offer it as authoritive unless you can provide citation.


Dan Downs KCRP

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It appears that in FAA airspace the following pertains:

 

14 CFR § 91.117 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.
 
where CFR = Code of Federal Regulations. Not sure what the comparable ICAO-land source would be. It's interesting to me that this section specifies both the 250 knot limit and the exception noted in (d).
 
 

John Wiesenfeld KPBI | FAA PPL/SEL/IFR in a galaxy long ago and far away | VATSIM PILOT P2

i7-11700K, 32 GB DDR4 3.6 GHz, MSI RTX 3070ti, Dell 4K monitor

 

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Could that differ between Europe and USA? I've always understood that ATC in Europe can approve high speed below FL100 in Class A-D airspace. Listening to Dutch ATC, I often hear controllers instruct flights "high speed approved".

Edit: probably can (partially) answer my own question now. According to the Dutch AIP, there are no speed restrictions for IFR flights in class A, B, and C airspace. Any restriction in that airspace is procedural.

 

Correct. This is different in ICAO areas.

 

 

Sure, it is routine to see heavies exceeding that. Houston has a NOTAM setting the limit to 280 full time... not sure where you are getting your information but I wouldn't offer it as authoritive unless you can provide citation.

 

He's correct. This is implied by 91.117. ATC is not a designee of the Administrator to waive any FAR. The only exemptions allowed to be offered by ATC are listed in b, and only in those areas around Class C and D airports.

 

Mind providing a link to that NOTAM? Sounds more like it would be an LOA for operators than a NOTAM (as I haven't found mention of 280 yet). Perhaps someone incorrectly cited the normal 280 descent speed on OPD STARs?

 

 

 


It's interesting to me that this section specifies both the 250 knot limit and the exception noted in (d).

 

Why wouldn't it? If you're setting a limit, you might as well state exemptions in the same place instead of sending people off on a wild goose chase through the other regs.


Kyle Rodgers

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Alright, now I'm getting confused. If I understand well, if the 250/FL100 is specified on charts, then the controller should be allowed to give a high speed clearance?

 

But if there is no such limitation like 250/FL100, then what would be the purpose of requesting a high speed clearance or being cleared by the controller?


Romain Roux

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Alright, now I'm getting confused. If I understand well, if the 250/FL100 is specified on charts, then the controller should be allowed to give a high speed clearance?

 

But if there is no such limitation like 250/FL100, then what would be the purpose of requesting a high speed clearance or being cleared by the controller?

 

What's the confusion? As I mentioned on page 1, the only applicability the 250/10 rule has is in the United States. Note that the only regs I was citing were the FARs, which only apply to the United States. Elsewhere, some SIDs have speed restrictions, or a generic speed restriction up to a certain altitude. In those areas, a controller may clear someone for high speed to cancel either the generic restriction, or the procedural restriction on the SID.

 

A controller in the United States, however, cannot waive the generic (regulatory) 250/10 requirement, though a pilot may fly faster than this if the min clean speed is above 250 (91.117d). Elsewhere? Depends on where you're flying, but it seems that controllers are able to, and do, cancel speed restrictions where possible.


Kyle Rodgers

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Elsewhere, some SIDs have speed restrictions, or a generic speed restriction up to a certain altitude. In those areas, a controller may clear someone for high speed to cancel either the generic restriction, or the procedural restriction on the SID.

 

So what you are saying if i was flying that SID in the RW lol the controller would mention about that 250 speed restriction doesn't apply? Unlike Vatsim that never mentined anything about it.


Vernon Howells

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So what you are saying if i was flying that SID in the RW lol the controller would mention about that 250 speed restriction doesn't apply? Unlike Vatsim that never mentined anything about it.

 

A non-FAA controller could choose to say something to the effect of "speed restrictions cancelled," or "high speed approved," yes.


Kyle Rodgers

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VATSIM's NY ARTCC tries to simulate Concorde historical operations in the context of what existed at the relevant time. Here's what the SOP says about speed restrictions:

 

After the initial departure heading/climb and around 4,000’-5,000’, speed restrictions were cancelled and SSTs were allowed to accelerate to approximately 400 knots below 10,000’. This was a special authorization from the Port Authority and FAA.

 

We are trained to cancel speed restrictions for the Concorde in accordance with that authorization although it presumably would have long ago been allowed to lapse. 


John Wiesenfeld KPBI | FAA PPL/SEL/IFR in a galaxy long ago and far away | VATSIM PILOT P2

i7-11700K, 32 GB DDR4 3.6 GHz, MSI RTX 3070ti, Dell 4K monitor

 

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We are trained to cancel speed restrictions for the Concorde in accordance with that authorization although it presumably would have long ago been allowed to lapse. 

 

That would've been a 91.117a exemption, handed down from the Administrator for the controllers to act upon. It was the Administrator waiving the requirement, essentially, and the controllers complying with that waiver, specific to that type of operation.

 

It's still true that a controller cannot waive any regulation (91.117 or not) simply as a matter of his or her position.

 

 

 

(Of course, for clarification, this only applies to FAA areas.)


Kyle Rodgers

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The only other point I would add to this is that in the UK the phraseology used to cancel SID/STAR altitude restrictions is "Climb (descend) now FLxxx". I would agree that the climb now instruction does not automatically imply a lifting of any speed restrictions, and so this should be queried with the controller if desired.

 

The 250/10 thing has been gone over a lot in the past, but in the UK there is no speed limit in Class A-C airspace for IFR flight, though most SIDs have a generic "maximum 250kts below FL100" and most STARs have a speed limit point at which you must be 250kts or less (normally not too far away from FL100 on a normal descent profile). Because there is no speed limit in these airspace classes, ATC may lift the SID (or STAR) speed restriction ("No ATC speed restriction").

 

In Class D-G there is a 250kts below FL100 restriction, and likewise for VFR flights in class C. I don't think ATC can lift this as it is law (HM Flying Club obviously operate to their own regulations which permit them to fling fast jets around at 400+kts in class G).

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Just found out the speed restriction won't apply if you have been cleared above the SID.


Vernon Howells

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