Would there be any aerodynamic advantage to mounting jet engines above the wings of an airliner instead of below?

I've seen pictures of a Fokker jet built like that, and have wondered what they were thinking.

Other answer:

Richard:
Aerodynamic advantage? No. Its always better to mount things underneath of a wing rather than on top which is why you rarely see engines mounted in this manner.

But there are a few other advantages to mounting the engines this way. First is less potential for engine damage due to FOD in comparison to under slung engines. Second is a lighter installation in comparison to the usual solution for FOD avoidance-a tail mounted engine. This is because wing mounted engines provide bending relief for the wing so it can be made lighter and either the aircraft wing attach can be made lighter or the aircraft can have a higher max zero fuel weight because the wings aren't carrying both the weight of engines and payload through the wing mounts.

Vincent G:
No, actually it would be detrimental. The upper surface of the wing is a low air pressure zone, and the engines are supposed to compress air. Put them in a low pressure zone, and they will be less efficient. The one thing that engines blowing on the upper surface might bring is an increased circulation that could boost lift at low speed, and blow the flaps through a Coanda effect.

On top of it, if the plane is at a high angle of attack, engines mounted above the wing could find themselves in the wake of the wing, which would not only reduce the efficiency, but would cause inlet distortion if only part of the airstream entering the engine is so affected while another part is not. This would cause a cyclical imbalance in the fan loading that will reduce efficiency, cause vibrations, increase the fatigue of the metallic rotating component. Mounting the engines above the wing is a very delicate tuning process, and the only advantage is permitting the landing gear to be shorter (and thus lighter) since they do not have to clear under-wing engine pods, and potential reduction in ingestion of foreign objects.

Ianab:
You are thinking of the VFW-Fokker 614.
https://en.wikipedia.org/wiki/VFW-Fokker…

The main reason was to keep the engines away from debris on rough runways, and allow shorter stronger landing gear.

There are a number if disadvantages to the design, so it's usually only used in special designs. The Beriev flying boat is another, where the high engines avoid water spray.

The Honda Jet also have engine mounted above the wings, although I'm not sure why…

Skipper747:
The only advantage I see would be better avoidance of FOD foreign object damage –
There is really NO aerodynamic advantage –
Airflow above the wing surface is not affected because of engine location –

Engine under wing insures better positive feed of fuel from wing tanks (above engine) –
This by gravity, no pump is really needed –

No Bozos:
The air above the wing is supposed to travel faster than the air below. It's what gives the wing its lifting coefficient. Mounting the engine above the wing would ruin that event and the plane would probably not lift the plane as well.

Any engine mounted above the plane of the wing is not mounted on the wing itself. It's mounted on the fuselage. Which is easier to brace against, but there isn't any speed or fuel efficiency benefit to doing this.Mounting the engine above the wing would ruin that event and the plane would probably not lift the plane as well.

Angela D:
the fokker jets had their engines on the aft fuselage, like a dc-9.

it permitted a cleaner wing, reduced the possibility of fod damage to the engines, and reduced engine noise in the cabin. a number of early jets had similar designs.

later: i had never seen the 614. fod was the main concern. the fact that they only made a handful of them should tell you something about the design.

PhotonX:
Some do.
http://aviation.stackexchange.com/questi… And I've seen special-use Soviet/Russian aircraft with top-mounted engines.
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Pilsner Man:
Boeing built two YC-14s for the USAF, and they flew successfully, but the program was scrapped.

Interesting read –> https://en.wikipedia.org/wiki/Boeing_YC-…

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