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To: HiTech RedNeck; phantomworker
With the jet exhaust at overhead level, that sucka has got to be LOUD inside.

Don't the over wing engines help with short field performance?

10 posted on 01/25/2006 10:42:17 PM PST by Paleo Conservative
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To: Paleo Conservative
Don't the over wing engines help with short field performance?

It's called the Coanda effect, where the airflow follows the surface of the airfoil design. That's why the Boeing YC-14 and Antonov An-72/74 had high-mounted engines, since the airflow from the engine exhaust actually followed the large wing flaps right behind the engine itself in a process called upper surface blowing. This results in dramatic reduction in takeoff and landing runs; indeed, the An-72 during its public demonstrations showed it could land and takeoff with the runway equivalent of not much more than the length of two American football fields!

The version of the An-74 proposed would probably use the same General Electric CF34 variant now used on the Embraer 190 regional jet airliner.

24 posted on 01/25/2006 11:18:26 PM PST by RayChuang88
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To: Paleo Conservative

Coanda Effect and its quieter than it would be if you hung the engines below the wing.


25 posted on 01/25/2006 11:22:51 PM PST by A.A. Cunningham
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To: Paleo Conservative

I seem to recall that early in the process of designing and bidding on the C-17, Boeing had an offering with the over-the-wing jet engines. Performance on short and unimproved runways was supposed to the reason for that design. The plane pictured looks like a standard aircraft with the OTW engines kludged on for experimental purposes. IMO. IRRC. YMMV.


58 posted on 01/26/2006 6:20:28 AM PST by ArrogantBustard (Western Civilisation is aborting, buggering, and contracepting itself out of existence.)
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To: Paleo Conservative

" Don't the over wing engines help with short field performance?"

Don't know about short field performance, that would depend more on the wing design but the high engines would be great for rough, unpaved fields. The engines would be much less likely to sustain FOD (foreign object damage).


63 posted on 01/26/2006 6:36:57 AM PST by dljordan
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