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Dead Engine and x wind

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Dead Engine and x wind

Old 30th Oct 2011, 22:41
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Dead Engine and x wind

In a crosswind approach with failed engine on a twin, of course you do not have a option to decide which engine to fail (right or left), but you may have an option to select which runway to land.

Question: Which side do you prefer the x wind to strike to the plane, good engine side or dead engine side?

And why?

Thanks in advance
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Old 30th Oct 2011, 22:50
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Which side do you prefer the x wind to strike to the plane, good engine side or dead engine side?
The good side. Thrust from the good engine will yaw the airplane to the bad side, so the wind from the good side against your tail fin etc will balance the yaw toward the good side.

If the wind is from the bad side, it will hit the side of the airplane on the bad side. Add that to the good engine yawing the airplane to the bad side. So bad + bad = very bad. Understand ? Can't give a more simple explanation than that.

For all sim checks, expect OEI approaches to have bad side crosswinds as that will give you the most handling problems. If it's really bad, cancel the rudder trim on short finals to give you better uncontrollably in the flare.
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Old 31st Oct 2011, 02:34
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ReverseFlight

I undesrstand well .

Thanks again
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Old 6th Nov 2011, 17:41
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Just spitballing, but wouldn't a crosswind from the "bad" side allow you to use more reverse thrust, if you were runway limited and you had reverse available?

For the flare, I also imagine it would be different if you had residual thrust on the good engine or if you had drag when it was at idle.
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Old 6th Nov 2011, 18:56
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Also depends whether you have a fire scenario. In which case you definitely want the suspect engine on the downwind side. Ie blowing the flames away from the fuselage.
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Old 7th Nov 2011, 10:14
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Hi JABBARA,

I understand from your post that you are asking about the Approach to Landing.
In flight the aircraft will be balanced because you will have trimmed out the rudder load - so it makes no difference from which side the X wind is blowing.

Once you are in the flare and reducing power, you'll need a rudder change to balance the power change, and additionally yaw to align. If the wind is from the failed engine side, the reduction in power will help the yaw towards the runway QDM. After Landing, asymmetric reverse thrust will tend to swing you towards the operating engine and help balance the weather cocking effect with the wind from the failed engine side.

So there you have two completely opposite arguments from Reverse Flight and myself - so don't worry about which side - "just do it" (with apologies to Starsky & Hutch)
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