Just got back from NZ after a flight on a Qantas A380. As I was an assisted passenger, I remained on board for a little while after landing at Sydnet and was lucky enough to chat to the Captain. I mentioned that I had followed the flight on the on-board TV and noticed that the A380 had not slowed at all until about 5000'. After answering how I knew that "rule", he told me that it was quite normal at Sydney for ATC to instruct the larger planes to maintain their speed until much lower than 10k feet.

Tell that to Radar Contact V4 and other simulator programs!

1 hour ago, IanHarrison said:

Tell that to Radar Contact V4 and other simulator programs!

I think RC4 allowed you to request to waive this speed limit. PF3 did enforce it during departure, but sometimes (if you behaved well) it waived the limit. For approach, it started suggesting lower speeds, but in 7 years, I can't recall having been told off for not reducing under 250 kt.

Now that I use FSHud, I see the 250 kt limit is not enforced at all. Only some speeds inidicated by ATC, but mostly for sequencing purposes.

I'll give you just a little insight on that limit😁. As you pointed out, there are some cases where you are allowed above 250 below 10,000. Now, I am FAA based and will follow FAA rules internationally, unless other wise it's specified by a specific governing body. When I first started flying the DC10, I learned that the FAA will look at this based on type. If you are a heavy, it's expected that you could be above 250 below 10,000. This happens frequently when you are departing. In the DC10, at 440,OOO pounds, clean minimum maneuver speed is at 252knots. At 590,000 pounds, it's 292kts. The climb schedule for heavies normally read as such: 

CLIMB SPEED SCHEDULE
The climb speed schedule is defined as the speed
schedule used to achieve the climb performance
provided in this section. The climb speeds below
10,000 feet are shown versus gross weight in
figure 4-1 and are based on 250 KIAS or the
minimum manuever speed, whichever is higher.
The climb speeds above 10,000 feet are as follows

As you can see, it's common to be above 250 when departing. I have never requested it due to my type. Now, when I flew KC10s, we would also do it for formation departures. In this case, FAA prefers that we expedite the join up, so the trailing jets will be in excess of minimum maneuver/250 in order to close and catch up to lead. Now, internationally, things can be different. During the wars, I would be returning back to my UAE base and the controller would say "no speed restriction below 10,000". Many debated this request and stuck with slowing before 10,000. Others said, they are controlling and took it as a request to keep the speed up. Internationally, I have never requested to be above 250 unless it was specified that I needed to be slower. There have been times where I have stayed slower to meet a turn on a SID/DP. Like those that take you towards terrain and turn you tightly. In those cases, I stay configure and maintain flap retract speed through the turn and then clean/speed up while my bank is limited to 15 degrees. In a sense ATC would not direct you to go against your flight manual. The FAA puts the onus on you to stay at or above your safe operating speeds.

As Rick said, in the US it's very strictly mandated that you shouldn't fly over 250kts below 10000ft (unless aircraft performance requires you to) but in the rest of the world they're less rigid about it. It makes the ATCer's life easier to have everyone at similar speeds (for spacing and turn radius etc) so the rule's on the books and they expect it (and we usually fly it) but if it's not too busy (or sometimes if you're getting in the way they will ask you) you can request high speed and they'll happily grant it.

Some aircraft (757?) have a windshield protection speed which is roughly 250 below 10 so they would probably respect it worldwide.

The big gotcha that often gets non US operaters (in the US) is when the ATCer says "no speed restriction" as most (non US) people believe this means "no speed restriction". In the States the ATCer doesn't have the authority to cancel the 250 below 10 speed restriction so what they mean is "you don't have to comply with any of the SID/STAR/previous ATC speed restrictions but you do have to obey the 250 below 10 speed restriction". And equally, when a US operator (not in the US) is told to "maintain high speed" the ATCer is expecting them to "maintain high speed" and not "maintain high speed until 10000ft and then slow down".

It's all part of the rich tapestry of international travel.

2 hours ago, iwebber said:

As Rick said, in the US it's very strictly mandated that you shouldn't fly over 250kts below 10000ft (unless aircraft performance requires you to) but in the rest of the world they're less rigid about it. It makes the ATCer's life easier to have everyone at similar speeds (for spacing and turn radius etc) so the rule's on the books and they expect it (and we usually fly it) but if it's not too busy (or sometimes if you're getting in the way they will ask you) you can request high speed and they'll happily grant it.

Some aircraft (757?) have a windshield protection speed which is roughly 250 below 10 so they would probably respect it worldwide.

The big gotcha that often gets non US operaters (in the US) is when the ATCer says "no speed restriction" as most (non US) people believe this means "no speed restriction". In the States the ATCer doesn't have the authority to cancel the 250 below 10 speed restriction so what they mean is "you don't have to comply with any of the SID/STAR/previous ATC speed restrictions but you do have to obey the 250 below 10 speed restriction". And equally, when a US operator (not in the US) is told to "maintain high speed" the ATCer is expecting them to "maintain high speed" and not "maintain high speed until 10000ft and then slow down".

It's all part of the rich tapestry of international travel.

Some clarification: 250 knots below 10,000 feet is an international standard worldwide. In the U.S., however, ATC cannot legally "instruct" a higher speed of 250 knots below 10,000 feet, and a no-speed restriction does not apply to any SID or STAR globally. 

For example, ATC can instruct higher speeds than 250 knots below 10,000 feet in Australia, but again, they cannot cancel speed limits during SIDs and STARs unless they take you off it. Also, as mentioned in this discussion, during departure, when the minimum clean speed (safety speed) exceeds 250 knots, generally based on weight for heavy or super aircraft, we let ATC know as a courtesy regarding our operational speed. Occasionally, we can maintain 250 knots without issues at lower weights, but typically, we find ourselves flying between 265 and 285 knots. For instance: "DEPARTURE XYZ025 HEAVY/SUPER, OUR MINIMUM/SAFETY SPEED today is 285 knots." 

In the last sentence, this isn't entirely accurate, as it depends on the country you are flying to. As you noted, things can sometimes get interesting.

On 2/4/2025 at 12:37 PM, IanHarrison said:

Tell that to Radar Contact V4 and other simulator programs!

I hope you enjoyed your holiday Ian. 😁 I’m sure you’re aware there is the option in RC4 to disable that for ICAO airports. It’s only FAA ones where it’s disabled.

In the real world I’m pretty sure exceptions were made as @G550flyermentions. When it was flying, Concorde would be given dispensation when safe to do so given it ate fuel at lower altitudes.

1 hour ago, Ray Proudfoot said:

I hope you enjoyed your holiday Ian. 😁 I’m sure you’re aware there is the option in RC4 to disable that for ICAO airports. It’s only FAA ones where it’s disabled.

In the real world I’m pretty sure exceptions were made as @G550flyermentions. When it was flying, Concorde would be given dispensation when safe to do so given it ate fuel at lower altitudes.

Answers: 1) Very much indeed. 2) Oh yes. I only mentioned RC because my old VA airline always objected to that disabling.