250 Knots IAS below 10,000 feet - is it adhered to?

Lndwarrior said:
I fly a lot thru northern California Central Valley. Over the past year (including last week) I have seen (a little too close for comfort) mulitple corporate jets exceeding 250 knots indicated on my adsb readout below 10,000 feet.

Is this an erroneous interpretion of mine regarding the adsb read-out I am seeing - or is the 250 knot limit not enforced?

Or?
TIA,
Gary
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In the 182 it is.
 
LongRoadBob said:
As long as one knew the winds at their altitude and temp one could calculate the IAS, at least fairly accurately right?
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Remember that TAS at 10000 and 250CAS is roughly 307 KTAS.

There was a time when we would do the, "Southwest 250". Those days are long gone.

Sent from my Pixel 2 XL using Tapatalk
 
Tantalum said:
Which implies that "ATC" and "the Administrator" are ubiquitous
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Separate lines of authority. “Administrator” is when waivers are in place by the FAA or military LOAs are established for certain military aircraft. Waiver examples are for air shows, SUAs, MTRs, etc. Another waiver by the Administrator was for HOU allowing greater than 250 kts on departure. I believe that expired in 2004. LOAs from the FAA are common for specific fighter type aircraft that require a higher speed just for safe operating practices. We had a 350 kt waiver for F-18s at our base. We had no other LOA signed by the FAA for transient fighters. However, we almost always looked the other way if an “out town” fighter showed up for the break.

Only authority for a specific controller has for approving above 250 kts, pertains to class C & D surface areas. Even then it’s only for a safe min speed IAW a flight manual.
 
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Velocity173 said:
Only authority for a specific controller has for allowing above 250 kts, pertains to class C & D surface areas. Even then it’s only for a safe min speed IAW a flight manual.
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Thanks! So the poster who wrote about ORD and allowances for greater than 250 knots for the Asian heavies may have just misheard things? I thought I've heard of controllers allowing 250 knots and greater as well. it is easy though to miss hear things, for arrival procedures I often hear the instruction to delete speed restrictions
 
kkoran said:
Do you mean 'synonymous'?
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That could work, I was intending the word ubiquitous to mean that perhaps "administrator" was the ubiquitous entity that governs all, much like peanuts are the ubiquitous snack of air carriers

I was never being much of a cunning linguist, perhaps I'll go post this question on GrammarTutorsOfAmerica
 
Seanaldinho said:
Also keep in mind, about the only person who can report you is the controller working you. Generally the controller isn't going to care (or have time to care) if you're a little over speed and they will issue a speed restriction if they need to ensure separation.
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"Airliner 1234, say airspeed"
"........... 250 knots indicated" (this while cranking down the speed selector)

"Southwest 250" is also widely understood.
 
I've gone over 250 below 10 plenty of times. Did it last week going into PBI. Perfectly legal.
 
In the airline world you just don’t break the 250 below 10 limit. Having said that, taking off heavy in the 767, minimum clean speed can be 252 so then, yes, we break it just barely. Of course as someone already mentioned this is allowed.

Ten or fifteen years ago, IAH was doing a test and you could ask for “free speed” on departure and we would accelerate to 320 or so below 10 in the climb. That test is over now.
 
Flying a 737 from BWI to SFB descending through 11,000 slowing down, we were handed of to Jacksonville approach. We checked in and were immediately told to maintain present speed.

Us: Uh...approach were are doing 325 kts.
Approach: Roger. Descend and maintain 5,000 ft. Maintain present speed.
Us: Roger. Present speed...5,000ft.

After several minutes at 5,000 ft. we were assigned 170 kts. Slowed down and several minutes later were handed off to SFB tower. Nothing was ever said or heard about it again. Still don't know why were assigned that other than ATC wanted it. To this day I have not found out if that was even a legal speed assignment from ATC.

Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.

Noah W
 
Noah Werka said:
Flying a 737 from BWI to SFB descending through 11,000 slowing down, we were handed of to Jacksonville approach. We checked in and were immediately told to maintain present speed.

Us: Uh...approach were are doing 325 kts.
Approach: Roger. Descend and maintain 5,000 ft. Maintain present speed.
Us: Roger. Present speed...5,000ft.

After several minutes at 5,000 ft. we were assigned 170 kts. Slowed down and several minutes later were handed off to SFB tower. Nothing was ever said or heard about it again. Still don't know why were assigned that other than ATC wanted it. To this day I have not found out if that was even a legal speed assignment from ATC.

Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.

Noah W
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Seems fairly straightforward...

Velocity173 said:
Separate lines of authority. “Administrator” is when waivers are in place by the FAA or military LOAs are established for certain military aircraft. Waiver examples are for air shows, SUAs, MTRs, etc. Another waiver by the Administrator was for HOU allowing greater than 250 kts on departure. I believe that expired in 2004. LOAs from the FAA are common for specific fighter type aircraft that require a higher speed just for safe operating practices. We had a 350 kt waiver for F-18s at our base. We had no other LOA signed by the FAA for transient fighters. However, we almost always looked the other way if an “out town” fighter showed up for the break.

Only authority for a specific controller has for approving above 250 kts, pertains to class C & D surface areas. Even then it’s only for a safe min speed IAW a flight manual.
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Noah Werka said:
Flying a 737 from BWI to SFB descending through 11,000 slowing down, we were handed of to Jacksonville approach. We checked in and were immediately told to maintain present speed.

Us: Uh...approach were are doing 325 kts.
Approach: Roger. Descend and maintain 5,000 ft. Maintain present speed.
Us: Roger. Present speed...5,000ft.

After several minutes at 5,000 ft. we were assigned 170 kts. Slowed down and several minutes later were handed off to SFB tower. Nothing was ever said or heard about it again. Still don't know why were assigned that other than ATC wanted it. To this day I have not found out if that was even a legal speed assignment from ATC.

Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.

Noah W
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No, it is not legal.
 
Noah Werka said:
Flying a 737 from BWI to SFB descending through 11,000 slowing down, we were handed of to Jacksonville approach. We checked in and were immediately told to maintain present speed.

Us: Uh...approach were are doing 325 kts.
Approach: Roger. Descend and maintain 5,000 ft. Maintain present speed.
Us: Roger. Present speed...5,000ft.

After several minutes at 5,000 ft. we were assigned 170 kts. Slowed down and several minutes later were handed off to SFB tower. Nothing was ever said or heard about it again. Still don't know why were assigned that other than ATC wanted it. To this day I have not found out if that was even a legal speed assignment from ATC.

Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.

Noah W
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The 170 is legal if you were within 20 miles of the airport. The 325 assignment isn’t legal...within 12 miles of shore. ATC doesn’t have authority to override the FARs.
 
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Tantalum said:
Which implies that "ATC" and "the Administrator" are ubiquitous
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No. A US controller does not have the authority to waive the 250kt below 10,000' limit. As has been pointed out, the ORD5 departure requires 250kts until advised so the crew was notifying ATC that they could not comply with that limit.

Crews may ask to go faster than 10,000' but what they are really doing is notifying ATC that they will be flying faster in accordance with the exceptions in the regulation.

Noah Werka said:
Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.
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Were you more than 12 miles offshore?
 
Tantalum said:
"(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."
Which seems beautifully vague. I'm sure the Concorde can be operated "safely" under 250. Wonder what the official SOP is or if there is a specific Vspeed this is referring to, like Va for instance. If we go by certain minimum speeds then a fully laden swallow (I mean 747) will have a minimum flaps clean speed well above 250 knots.. do they climb to 10K with flaps out, or do they accelerate up to 280 or so and clean up?
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Not really vague, the various safe airspeeds are all defined in procedures for weights and flap configurations.

Also nuts, is the sheer speeds that jet planes fly. If I recall correctly from the days I was an even bigger aviation dork and had more free time on my hands the PMDG 747 climb speeds were 250 knots to 10K then 340 knots to FL250 transitioning to Mach 0.84 for the remainder of the climb. 340 knots indicated for a transport civilian jet. NUTS
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Yeah, these swept wing jets are fast, no two ways about it. My wife's flying the Challenger 300 these days. 250 to 10k, something pushing 300 into the flight levels, and something in the M0.7s or maybe 0.8 for the climb. I don't know the exact numbers, and she's sleeping. I'll listen on LiveATC and heard her get told to slow to 270 for the climb at one point, and it always amazes me how quickly they're at FL410-450 after takeoff. But the faster you go, the faster you need to go (and can go).
 
Noah Werka said:
Flying a 737 from BWI to SFB descending through 11,000 slowing down, we were handed of to Jacksonville approach. We checked in and were immediately told to maintain present speed.

Us: Uh...approach were are doing 325 kts.
Approach: Roger. Descend and maintain 5,000 ft. Maintain present speed.
Us: Roger. Present speed...5,000ft.

After several minutes at 5,000 ft. we were assigned 170 kts. Slowed down and several minutes later were handed off to SFB tower. Nothing was ever said or heard about it again. Still don't know why were assigned that other than ATC wanted it. To this day I have not found out if that was even a legal speed assignment from ATC.

Does a controller have authority to do that king of stuff? Haven't found anyone that really knows the answer.

Noah W
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You just busted 91.117. ATC cannot waive the 250/10k limitation. 91.117 specifically says only Administrator can waive the 250 below 10, but ATC can waive the 200 below C etc.
Same as ATC saying "maintain maximum forward speed" and you going 320kts or whatever your redline is. Just not legal.
 
mtuomi said:
You just busted 91.117. ATC cannot waive the 250/10k limitation. 91.117 specifically says only Administrator can waive the 250 below 10, but ATC can waive the 200 below C etc.
Same as ATC saying "maintain maximum forward speed" and you going 320kts or whatever your redline is. Just not legal.
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You might want to reread that. They can waive it within 4 nm. of the primary airport while in the C, but it says nothing about waiving it while UNDER the airspace..
 
In the military jets, we will climb and descend at 300kts below 10k for controllability reasons. The airplane flies fine at 250, but if you have to maneuver hard to avoid traffic it just tends to skid around below 300 as opposed to actually turning. Once above 10k we accelerate to 350kts.

Common misconception is that we simply roll around ignoring the FAR’s, but that simply ain’t true.

Now, if we are on an approved MTR (IR/VR route) that’s another story!
 
RhinoDrvr said:
In the military jets, we will climb and descend at 300kts below 10k for controllability reasons. The airplane flies fine at 250, but if you have to maneuver hard to avoid traffic it just tends to skid around below 300 as opposed to actually turning. Once above 10k we accelerate to 350kts.

Common misconception is that we simply roll around ignoring the FAR’s, but that simply ain’t true.

Now, if we are on an approved MTR (IR/VR route) that’s another story!
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We actually fly at whatever speed your MDS specifies. Sounds like the Super is 300. In the Eagle and Strike Eagle, we accel to 350 right after takeoff and climb there till we hit .9M (in the C model) and swap to a fixed .9M climb.
 
EvilEagle said:
We actually fly at whatever speed your MDS specifies. Sounds like the Super is 300. In the Eagle and Strike Eagle, we accel to 350 right after takeoff and climb there till we hit .9M (in the C model) and swap to a fixed .9M climb.
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Article in Flying Mag years ago a Strike Eagle pilot based at Bagram said they would land with a full load at 210 kts. Just thought that was an amazing number but does make sense due to the high DA and heavy load.

Walking out to the flightline one morning I just happened to be watching one land and I see this black doughnut flying thru the air. Took the departure end cable and closed the runway for hours. :(
 
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EvilEagle said:
We actually fly at whatever speed your MDS specifies. Sounds like the Super is 300. In the Eagle and Strike Eagle, we accel to 350 right after takeoff and climb there till we hit .9M (in the C model) and swap to a fixed .9M climb.
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Ah, got me, Evil! I shouldn’t have over-generalized.
 
Velocity173 said:
Article in Flying Mag years ago a Strike Eagle pilot based at Bagram said they would land with a full load at 210 kts. Just thought that was an amazing number but does make sense due to the high DA and heavy load.

Walking out to the flightline one morning I just happened to be watching one land and I see this black doughnut flying thru the air. Took the departure end cable and closed the runway for hours. :(
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210 is pretty darn fast on final. Both versions of the Eagle just fly AOA on final, not a specific KIAS. There's a formula that'll give you the IAS, but we all know "about" where it is then fine tune it with AOA. Bagram was a strange place to fly for sure - especially in the summer. Some strike eagle dudes were carrying 5 x 2,000# bombs plus fuel tanks, etc. If you brought all that back I can imagine 210 is in the ballpark.
 
I was a bit taken aback last week when Houston got lippy with me about 1) not being able to slow for an approach behind a C-172 at KVCT, and 2) being above 250 below 10k. I was conducting a category check with a student so I was in role and allowing the candidate make all the decisions. But these jackalopes kept pressing about it and my student finally relented and attempted to slow the rocket down, so I had to break out of role and avoid a legitimate safety of flight situation. That's when the fun started.

It's not like we're not local to this region, nor is Houston center new at the controlling non-standard aircraft game. So I was sincerely surprised by the lack of courtesy and buffoonish lack of knowledge of their own jobs that particular afternoon. Dude actually sarcastically replied to my student: " ----- XX, you mean to tell me you really caaaaan't do 170?". I could feel my skin turning green and the flight suit get snug, but I took the high road and told him to just get me long vectors until he got the separation he needed.

Then we get it again coming back to home plate below 10K. Clownshoes starts patronizing my student like we're new at this game:
Hst: "----- XX say airspeed"
Us: "3-zero-zero Kanots"
Hst *queue douchebag patronizing tone*: "------ XX, you áre aware of the restriction to maintain 250 below 10-thousand right?"
Uncle Hindsight in the RCP:
giphy.gif


Suffice to say when you have to quote LOAs and spelling out your aircraft type and approach category, you know we've gone off the rails on the mutual courtesy train between ATC and operators. Thankfully this is the exception and not the rule to our daily relationship.

Slowing to 170 clean heavyweight a mere 2000 feet from terra firma?...
tenor.gif


:D:D
 
kayoh190 said:
But to be clear, there is no speed limit for Class B airspace
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:confused2: The only exception I see to the speed limit inside class B (other than paragraph (d)) is for the 200 knot requirement in paragraph (b):

§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.

[Doc. No. 18334, 54 FR 34292, Aug. 18, 1989, as amended by Amdt. 91-219, 55 FR 34708, Aug. 24, 1990; Amdt. 91-227, 56 FR 65657, Dec. 17, 1991; Amdt. 91-233, 58 FR 43554, Aug. 17, 1993]​
 
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hindsight2020 said:
I was a bit taken aback last week when Houston got lippy with me about 1) not being able to slow for an approach behind a C-172 at KVCT, and 2) being above 250 below 10k. I was conducting a category check with a student so I was in role and allowing the candidate make all the decisions. But these jackalopes kept pressing about it and my student finally relented and attempted to slow the rocket down, so I had to break out of role and avoid a legitimate safety of flight situation. That's when the fun started.

It's not like we're not local to this region, nor is Houston center new at the controlling non-standard aircraft game. So I was sincerely surprised by the lack of courtesy and buffoonish lack of knowledge of their own jobs that particular afternoon. Dude actually sarcastically replied to my student: " ----- XX, you mean to tell me you really caaaaan't do 170?". I could feel my skin turning green and the flight suit get snug, but I took the high road and told him to just get me long vectors until he got the separation he needed.

Then we get it again coming back to home plate below 10K. Clownshoes starts patronizing my student like we're new at this game:
Hst: "----- XX say airspeed"
Us: "3-zero-zero Kanots"
Hst *queue douchebag patronizing tone*: "------ XX, you áre aware of the restriction to maintain 250 below 10-thousand right?"
Uncle Hindsight in the RCP:
giphy.gif


Suffice to say when you have to quote LOAs and spelling out your aircraft type and approach category, you know we've gone off the rails on the mutual courtesy train between ATC and operators. Thankfully this is the exception and not the rule to our daily relationship.

Slowing to 170 clean heavyweight a mere 2000 feet from terra firma?...
tenor.gif


:D:D
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We always gave T-38s a wide birth in ATC. Even behind an F-18 you’d have a 40 kt overtake on final.

Speaking of the mighty Talon. Just ordered one of these the other day.

https://roncole.net/products/special-24x18-northrop-t-38a-talon-aircraft-aluminum-relic-display
 
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Velocity173 said:
We always have T-38s a wide birth in ATC. Even behind an F-18 you’d have a 40 kt overtake.

Speaking of the mighty Talon. Just ordered one of these the other day.

https://roncole.net/products/special-24x18-northrop-t-38a-talon-aircraft-aluminum-relic-display
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Had a Navy TPS candidate two weeks ago and we're running through basic landing ops at the aux field. Hornet guy, kept wanting to get me killed getting slow in the final turn. Welcome to the equalizer I told him.

Terrible fighter, great "SA saturator" and AHC planform though.

The T-X will be a pussycat by comparison, judging by the inside baseball specs I'm getting from the program bros in St. Louis and Wright Patt. It may even have a safe space button for the student when whatever remnant of the fighter culture left in the training IP cadre hurt their feelings :D. One day when this thing is IOC I'll tell ya all about the absolute buffoonery that is DoD acquisitions. It ought to make the civilian tax paying base incensed, if it weren't for the fact some of them benefit from the graft in the first place. The world is grey. Aaaand I digress.
 
Here’s a can of worms I’ll open.

You can go faster than 250 knots below 10,000’ if the minimum speed for your aircraft weight, with the flaps and slats retracted is greater than 250 knots. There was a lot of discussion of this at our company because some pilots were adhering to the 250 knot restriction by climbing to 10,000’ with the slats/flaps extended, then retracting them above 10,000’ and accelerating.

Then the company published this in our Operations Manual:
The speed limits of FAR 91.117 are not intended to interfere with the normal flap and slat retraction speed schedule for departing traffic. During departure if the speed achieved by the normal takeoff profile should exceed the speed limit, that airspeed may be maintained.

NOTE: This only applies to the takeoff phase of flight. During any other phase of flight, i.e., en route or approach, airspeed must be in accordance with FAR 91.117.
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I don’t have the time or inclination to go search for something more official published by the FAA. Since the airlines hire people to liaise with the FAA on issues like this, and the POI signed off on it, I’m going to go with they’re okay with it.
 
Sluggo63 said:
Here’s a can of worms I’ll open.

You can go faster than 250 knots below 10,000’ if the minimum speed for your aircraft weight, with the flaps and slats retracted is greater than 250 knots. There was a lot of discussion of this at our company because some pilots were adhering to the 250 knot restriction by climbing to 10,000’ with the slats/flaps extended, then retracting them above 10,000’ and accelerating.

Then the company published this in our Operations Manual:


I don’t have the time or inclination to go search for something more official published by the FAA. Since the airlines hire people to liaise with the FAA on issues like this, and the POI signed off on it, I’m going to go with they’re okay with it.
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The controller’s manual states a minimum safe speed from a “airplane flight manual” but I think a GOM would be a close enough interpretation. Especially since it’s stamped by the FAA.
 
Velocity173 said:
The controller’s manual states a minimum safe speed from a “airplane flight manual” but I think a GOM would be a close enough interpretation. Especially since it’s stamped by the FAA.
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I'm no expert, but my understanding is that pilots are bound by the regulations, not the controller's manual, except to the extent that a controller issues a clearance or instruction based on the controller's manual (which would bring 14 CFR 91.123 into play). Another exception is if the regulation says "unless otherwise authorized or required by ATC," as it does in the case of 14 CFR 91.117(b). The speed-limit exception in 91.117(d) references "the minimum safe airspeed for any particular operation," not the AFM, which supports your belief that adherence to an FAA-approved operations manual would be sufficient.
 
Palmpilot said:
I'm no expert, but my understanding is that pilots are bound by the regulations, not the controller's manual, except to the extent that a controller issues a clearance or instruction based on the controller's manual (which would bring 14 CFR 91.123 into play). Another exception is if the regulation says "unless otherwise authorized or required by ATC," as it does in the case of 14 CFR 91.117(b). The speed-limit exception in 91.117(d) references "the minimum safe airspeed for any particular operation," not the AFM, which supports your belief that adherence to an FAA-approved operations manual would be sufficient.
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Not saying pilots are bound by the controllers manual. Just giving an FAA reference (more official published by the FAA) on how the controller side would look at it. When a controller issues a PD, they have to have something to go on. In the case of going over 250 below 10,000 ft, the vast majority don’t care. Never even heard of a PD being issued for speeding either.
 
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