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pros and cons of over fueselage air intakes

ok you aerodynamics arm chair generals,

what are the pros and cons of over fueselage air intakes?

the F-107 got a lot of flak for it, and they cited concerns over pilot safety during ejection

but the stealth gen seems to use it quite a bit (granted a lot are on the sides or unmanned). I’m guessing from surface based radars it may seem stealthier? how does this affect agility

http://www.resume.shanaberger.com/images/F-107_main.jpg
http://files.harrispublications.com/wp-content/uploads/sites/8/2014/05/Boeing-Bird-of-Prey-artist-concept.jpg

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By: Ryan - 14th April 2017 at 15:18

Obstruction of airflow going over the top of the wing and less air going over top of wing due to engine taking it.

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By: Arabella-Cox - 14th April 2017 at 14:49

Firmly agree with the above that disturbed airflow to the engine at high AOA is the main con- effectively making such a placement a non-starter for fighters.

Would also add reduced rearward visibility (especially on something like the F-107) as a con. Checking your six is important in any fighter.

Agree with the pros listed above, especially reduced RCS/easier to mask and FOD. Would add increased flight deck crew safety and reduced stream ingestion in an aircraft carrier application.

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By: fltgshdw - 14th April 2017 at 12:46

Consider which combat aircraft have actually implemented an over-wing inlet in the past forty years: F-117, B-2, Bird of Prey, X-45, X-47, nEUROn, Taranis. These are all dedicated strike/bomber type aircraft that adopted an over-wing inlet purely for low observable reasons.

Any fighter – any aircraft that is expected to see severe maneuvers and high angles of attack – will avoid an over-wing inlet like the plague.

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By: halloweene - 13th April 2017 at 13:43

Mounting the intake on top is a great way to starve the engine of airflow in a tight turn, or any elevated AoA.

/agree

Only interest i could see is discretion vs ground installations.

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By: FBW - 13th April 2017 at 13:24

Mounting the intake on top is a great way to starve the engine of airflow in a tight turn, or any elevated AoA.

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By: Nils - 13th April 2017 at 08:32

i guess there are certain advantages, such as reduced bird strike/FOD risk. also frees up more space at the bottom for weapons bays for example.
i guess the biggest risk is that its prone to hot air ingestion when flying behind another aircraft in formation. also, it could ingest fuel when A2A refeuling goes wrong.

ejection could go wrong, but if the egine shuts off when ejection is triggered and given enough thrust in the ejection rockets, i think the risks are similar to that of a conventional aircraft. its only dangerous if you dont have an ejection seat (like in the Heinkel He162).

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