RAF Chinook downwash allegedly sets off land mines
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used to be known as what you mentioned. now its Foreign Object Damage.Originally posted by equlus84:FOD--- Foreign Objects & Debris
but the old term is still recognised during daily communication.
"check shoes for FOD", "do FOD walks" -
That is to prevent TFOA (Things Falling Off Aircraft).Originally posted by equlus84:I think down wash is a real serious thing. Bcos those who did heli rappeling will know how fast one goes down the rope due to down wash. If u did it from an ordinary building, the speed is very much slower. But i don't think the down wash is strong enough to trigger mines. But some times dunno why our unit so kanchiong, must remove helmet net and not lose items to be hung outside, when taking helo
if there's TFOA, then you have a helluva report to hand in.
one small thing that falls off can probably do enough damage when it hits the ground.
heard of the coin falling from 5 storeys compared to falling off 20 storeys theory?
secondly, it is not your unit that's kanchiong. it is the safety regulation of the RSAF. -
The term downwash has two meanings within the field of aerodynamics.Originally posted by missqi:what is a downwash?
1. One meaning, used most often by non-engineers (in particular pilots), refers to the forcing of air downward during the creation of lift. This usage is most common with regard to helicopters where the effect is most dramatic.
2. The other meaning, used most often by engineers, refers to the flow of air behind a wing. The downwash behind a wing is a consequence of the wing trailing vortex system. This downwash is experienced by a horizontal tail placed in the flow behind a wing. The primary influence of downwash of on the horizontal edge is the reduction of tail angle of attack, and consequently the reduction of the tail lift. This reduction depends on the longitudinal and vertical distance between wing and horizontal tail. A horizontal tail that is close to the wing is more affected by the wing downwash than one that is far from the wing. In aircraft design, this influence must be avoided by locating the horizontal tail far and high enough compared with the location of the wing. In front of the wing the term upwash is used instead of downwash. Upwash is particularly important in the case of a canard airplane design.
These meanings are closely related. They differ primarily in terms of scale. The "pilot's meaning" is a much larger scale effect than the "engineer's meaning".
Downwash is also related to the difference in pressure between the top and bottom of a wing, which is required for lift. At the tip of a wing, this difference in pressure will "leak" around the tips from the bottom to the top, resulting in wingtip vortices.
Trailing vortices and downwash are caused by the same phenomenon. The energy used to create trailing vortices is a component of induced drag. -
FOD is only situated on the ground.Originally posted by martin_lim85:FODs aka Flight O(???) Debris cos loose item may cause alot of trouble in runway things get to fall off if these things fall off and cos the aircraft to malfunction thats bad
anything that falls off the aircraft during flight will be termed as TFOA.
and FOD to the engine isn't a very big issue with the helicopters because the engines are high up.
FOD is more critical to fighter jets / fixed wing... especially the F-16 with the air intake under the belly. -
oops wrong ideaOriginally posted by kopiosatu:FOD is only situated on the ground.
anything that falls off the aircraft during flight will be termed as TFOA.
and FOD to the engine isn't a very big issue with the helicopters because the engines are high up.
FOD is more critical to fighter jets / fixed wing... especially the F-16 with the air intake under the belly.
but downwash is 'fun' sometimes the 'cool' heavy breeze -
Well from what i have noticed , our own RAF , millitary units and even policemen are rank according to their school certificate , as long as you are dip holder you can be 3rd sergent liao after sispec . Whereas in other country millitary unit , their rank is gained by years of experience in millitary service and some may have actual war experience which is to say even if he is just a cpl , he may have much more actual war or battle experience then our major may have never gone through any actual war experience at all .