Crosswind or wake turbulence ?

[yurski]

What is main problem in this tricky landing of Russian cargo plane IL-76. Crosswind or wake turbulence from Typhoon? Crosswind landing of cargo plane Ilyushin IL-76 at Farnborough FIA14 - YouTube (http://youtu.be/AoQqfPVtNBo)

[Basil]

Just crosswind.

[AndoniP]

look at the efflux from the typhoon, it immediately gets blown to the right, the trees at the bottom would also indicate it's just windy conditions

[Talkdownman]

Typhoon MTOM is approx 23500Kgs therefore in the 'Small' Wake Turbulence Category.
IL76 MTOM is 195000Kgs therefore in the 'Heavy' Wake Turbulence Category (hardly surprising…)

From CAP493: In the case of an IL76 behind a Typhoon separation for wake turbulence reasons alone is not necessary.

I don't think the IL76 would have even felt a tickle…a crosswind, on the other hand, is a different matter, regardless of mass...

[+TSRA]

You'll also notice that the Typhoon seems to have been taking off. The Ilyushin was landing. As wake turbulence does not start until the aircraft rotates off the ground, there is no way the Ilyushin would have been affected by the Typhoon's wake even if you were not dealing with a small/heavy category difference - it would have landed well before the point that the Typhoon rotated...never mind the effects of wind on the wake. Looks either like a low level wind shift (considering the gusts in the trees) or a pilot over-controlling on landing (which never happens). ;)

[yurski]

Thank you guys for your answers!

[ManUtd1999]

As wake turbulence does not start until the aircraft rotates off the ground, there is no way the Ilyushin would have been affected by the Typhoon's wake even if you were not dealing with a small/heavy category difference -
Why does wake turbulence start at rotation? Surely as soon as the wings are producing lift (ie, the aircraft is at a reasonable speed), there will be some wake turbulence? Granted it will be lower until AoA is increased (rotation), but not negligible.

[oceanhawk]

As has been stated, wake turbulence does not start until the aircraft rotates off the ground ~ Fact.

[DaveReidUK]

Granted it will be lower until AoA is increased (rotation), but not negligible.

Most aircraft do indeed produce negligible lift at incidences that correspond to the nosewheel on the runway.

That's why they need to rotate. :O

[Armchairflyer]

I suppose one could also say that wake turbulence is produced as soon as the wings (and not the landing gear) bear the weight of the plane (or most of it).