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KRosh
15th Jun 2010, 23:08
Hi everyone!

I have a theory question about crosswind landings if someone here can help please. It's about landing in a crosswind with a failed engine, firstly in a small twin and then in a large jet aircraft.

From ground school I remember that in a small twin, it's easier to control a failed engine which is into wind, helping with adverse yaw when coming in for a landing. For example if the port engine has failed, the aircraft will yaw to the left, making a right rudder input necessary. Now landing in this configuration, a crosswind from the left would help with yaw and right rudder forces. However after an off chance conversation with a friend, I'm led to believe that the opposite is true with an airliner because of weathercocking. So in an airliner, a crosswind from the right would be more easier to handle than one from the left with a port engine failure due to weathercocking and possibly because of the large vertical tailplane of the airliner.

I'm not quite sure what the exact answer is and would appreciate some clarification to brush up on my theory!

Thanks a million,

KRosh.

welliewanger
19th Jun 2010, 15:58
Your friend is right in both instances. A failed left hand engine will cause yaw to the left. A crosswind from the left will cause the aircraft to weathercock left. Combine the two and the approach phase could be at a significant crab angle.Once the throttles are closed, any yaw effect caused by the failed engine disappears. We could debate which would be preferrable ad nauseum.

KRosh
19th Jun 2010, 21:14
Thanks for your reply welliewanger. Just to clarify, are you saying that an airliner such as an A320 or a B737 will always weathercock into wind on an approach? In other words, the opposite to what happens in a small twin? Or are there just too many variables to say whether an airliner will or won't weathercock?

Thanks very much!

KRosh.