Speed limit above 10,000ft

[c172captain]

I'm having a somewhat argument with a thick-headed student who's sole purpose in life is to give me crap, but he's pretty cool.


Anyways he is convinced that there is NO speed limit above 10,000ft and I know for a fact that it is Mach .99. I just can't find the FAR to prove it. I have checked the obvious regulation, 91.117, which specifically says "aircraft speed," but says nothing about speed limit above 10,000ft, only below 10,000ft.


Any help?

 

[Berkut]

91.817?

 

[pwttogfk]

91.817...whoops, beat to it

 

[bdhill1979]

I shaved with a Mach 3 yesterday

 

[c172captain]

91.817?

Thanks for being a better researcher than I am

 

[Hacker15e]

FWIW even military guys have to adhere to the same restriction.

There are some areas specifically identified by FAA LOA where military aircraft are allowed to go supersonic above (and below) 10K. Most of them are in Restricted Areas like the Nellis Test and Training Range, but there are some areas outside of restricted airspace where it is allowed, too, but above certain FLs.

 

[JordanD]

I shaved with a Mach 3 yesterday

There's no time to think when you're shaving with a mach 3! You think, you're dead!

 

[moxiepilot]

lol.

 

[bdhill1979]

bogey on our six, he's got tone!

 

[Approach Control]

Certainly not a pilot yet, but I've seen this debated before elsewhere - so I looked it up.

As I understand it, .9 mach is the limit, but one can obtain a waiver issued from Control for "special flight conditions" which enables speeds in excess of .9 mach. From what I understand, Control can authorize for the purpose of "exhibition flights" (special flight conditions) and those have historically fallen into 99.9% military exhibition category at airshows.

On the flip side of this question of course, is the 250 kts under 10,000 ft restriction (outside of controlled airspace). What is the final ruling on this restriction, guys?

From what I was able to glean, the FARs require the 250 kts and Control may indee "request" 250 kts, but if 250 kts does not allow for minimum/safe controlability of your particular aircraft, then an airspeed greater than 250 kts is inherently approved. It would seem like an old loophole in the regs. as most modern airfoil designs (talking about the jets) don't require very high airspeeds below 10,000 ft in order to maintain minimum controlable airspeed.

Is any of this below 250 kts stuff true?

 

[mooneyguy]

Certainly not a pilot yet, but I've seen this debated before elsewhere - so I looked it up.

As I understand it, .9 mach is the limit, but one can obtain a waiver issued from Control for "special flight conditions" which enables speeds in excess of .9 mach. From what I understand, Control can authorize for the purpose of "exhibition flights" (special flight conditions) and those have historically fallen into 99.9% military exhibition category at airshows.

On the flip side of this question of course, is the 250 kts under 10,000 ft restriction (outside of controlled airspace). What is the final ruling on this restriction, guys?

From what I was able to glean, the FARs require the 250 kts and Control may indee "request" 250 kts, but if 250 kts does not allow for minimum/safe controlability of your particular aircraft, then an airspeed greater than 250 kts is inherently approved. It would seem like an old loophole in the regs. as most modern airfoil designs (talking about the jets) don't require very high airspeeds below 10,000 ft in order to maintain minimum controlable airspeed.

Is any of this below 250 kts stuff true?

Find you a dc10-md11 pilot or 747 pilot they might think otherwise.

 

[Hacker15e]

From what I was able to glean, the FARs require the 250 kts and Control may indee "request" 250 kts, but if 250 kts does not allow for minimum/safe controlability of your particular aircraft, then an airspeed greater than 250 kts is inherently approved. It would seem like an old loophole in the regs. as most modern airfoil designs (talking about the jets) don't require very high airspeeds below 10,000 ft in order to maintain minimum controlable airspeed.

The above 250 knot waiver for certain military aircraft is not implied -- it is explicitly stated in a LOA betweent the Department of Defense and the FAA. This is a copy of the one from 30 years ago. I'm sure there is a newer agreement out there, but this is the only one I've physically laid eyes on.

Each service, further, has specific restrictions on those waivered speeds. Here is a part of the USAF's message sent to all aircrew on the subject from several years ago:

ALL AIRCREW MEMBERS WILL REVIEW THE FAA AUTHORIZATION TO EXCEED 250 KNOTS BELOW 10,000 MSL LOCATED IN FLIP GENERAL PLANNING SECTION E, PART 5-35 AND AFI 11-202V3, GENERAL FLIGHT RULES, PARAGRAPH 5.7.5.

THE AIRCRAFT FLIGHT MANUAL MENTIONED IN FLIP GP IS THE SAME AS THE AIRCRAFT TECHNICAL ORDER (T.O.).

AIRCREW FLYING IN CONUS BELOW 10,000 MSL (OUTSIDE SPECIAL USE AIRSPACE) WILL FLY AT 250 KNOTS UNLESS MANEUVERING AIRSPEEDS PUBLISHED IN THE AIRCRAFT T.O. DICTATE OTHERWISE. IF SAFE MANEUVERING AIRSPEEDS FOR A PARTICULAR PHASE OF FLIGHT ARE NOT CONTAINED IN THE AIRCRAFT T.O., USE THE GUIDANCE CONTAINED IN THIS FCIF. IF THE SAFE MANEUVERING AIRSPEED IS LISTED AS A RANGE, FLY THE SLOWEST SPEED PRACTICAL IN THAT RANGE, BASED ON WEIGHT AND CONFIGURATION.

The message goes on to identify the allowed speeds for specific aircraft and specific phases of flight, but it is too long to post here.

The bottom line is that even the waivers have specified speed limitations. It is not a free-for-all.