Tagged for overspeed at 10,500 ft.

[Roadrunner750]

I thought the overspeed penalty was "below" 10,000 ft., but on my KORD - KMIA flight as I reached 10,500 ft, the penalty flag notified me I was over 250 kts below 10,000 ft. The altimeters were set and current. Please clarify.

[AdmiralRolfe]

The altimeters were set and current.

When you say they were "current," do you mean they were at the correct barometric pressure and most likely NOT at 29.92 inHg? If this is the case, the client reads all altitude values from the standard barometric pressure, which may be the incorrect pressure setting for a particular area. In general, the best way to avoid this is to slow down below 250 kts around 12000 ft.

[jch5pilot]

Hello,

As John says, the 250kt limit is active from FL100 (with 1013 or 29.92 set), not altitude 10,000 feet (with local pressure set). Hope that helps!

James

[Roadrunner750]

They were set to the "adjusted" KMIA setting, not 29.92. This never happened before.

[jch5pilot]

Hi again James,

That is probably why it happened. In order to fly Flight Levels you need to have 29.92 set. It could be that on your previous flights the pressure was not all that different from the ISA standard pressure setting, therefore the difference was not large enough to affect your flights. It could be the case that on your last flight there was a particularly low or high band of pressure in that region thus the difference between 29.92 and whatever pressure you had set was quite large, causing you to pick up this 'penalty', if you can call it that.

I wouldn't worry too much. Although it is nice to get 100% on all flights, sometimes things happen and you are bound to get a few 95% or 90% here and there. A few of the aircraft I fly have the landing lights on the landing gear thus I get 95% on all those flights done with that aircraft. You just have to live with it.

I doubt anyone else other than yourself will actually look at your average ratings anyway, so don't worry!

Regards,

James

[AdmiralRolfe]

They were set to the "adjusted" KMIA setting, not 29.92. This never happened before.

That would explain it. If you're set to the local barometric pressure of KMIA, then you're not getting the flight level readings. The client checks the lights at "FL100" which is 10000 feet AT 29.92 inHg, even if your pressure settings are not at the standard barometric pressure.

[N8764E]

Well, I guess this can explain my fiasco I had with this... Thanks for the explaination though--NOTED