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good egg
15th Jul 2018, 20:52
Please excuse my naivety...

I’m curious how minimum clean speed varies with altitude, say from 10,000ft to SFC, in benign conditions for (a) a small regional jet, and (b) a turboprop.

I understand there are a number of variables but, generally speaking, is there a significant difference in minimum clean speed at 10,000ft compared with 2,000ft for either aircraft type? (I’m interested in approach operations here rather than on departure, if that makes a difference?)

AerocatS2A
15th Jul 2018, 21:35
There shouldn’t be a difference in min clean IAS for most types over that altitude range. There is a difference between high altitude clean speed and low altitude. In the type I fly we add 20 knots above FL270.

You will see a difference in TAS for the same indicated speed between 10000 and 2000 though.

good egg
16th Jul 2018, 05:04
Great, thank you

good egg
16th Jul 2018, 13:34
As an aside, I don’t suppose anyone could point me towards fuel burn data for various aircraft types in level overflight over the same altitude ranges as above, when flown at 250kts, 220kts and min. clean speed?

(I’m also interested in noise data for the above...is min. clean speed best for noise reduction on the ground? Is that dependent on which measure of noise is used?)

Thanks, hopefully in advance, of any pointers :)

good egg
19th Jul 2018, 19:06
Hmmm, perhaps a new thread for this question....