American Eagle CRJ900 scrapes wing on landing
[QUOTE]Well, at 30 kts crosswind and 132 kts approach speed you need around 9 degrees bank angle if no crab.
/QUOTE]
well, winds were variable 3 or 4 kts
Incident: Mesa CRJ9 at McAllen on Sep 29th 2015, wing tip strike on landing
/QUOTE]
well, winds were variable 3 or 4 kts
Incident: Mesa CRJ9 at McAllen on Sep 29th 2015, wing tip strike on landing
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Yes but; we can talk about angles all night long. Look at the attitude in the photo: now consider yourself on the inside sitting in the hot seat on RHS. Looking outside of the front window it must have been exciting and probably looked worse than from three outside. What were the control inputs?
Note that the seemingly extreme pitch attitude in the original picture could be an "optical illusion", because the camera wasn't held straight & level. Not saying that it is, just that it could be.
Look what happens if we straighten out the picture and measure the fuselage angle vs. the ground:
Now the camera-lens-aircraft geometry is uncertain and I'm not CSI... so the 7.2 degrees could be way off... but one possible hint is to look at the tail section: there's still quite a bit of clearance from the tail to the ground. So maybe the pitch attitude isn't as extreme as the original picture suggests.
Of course pictures do lie so we really can only speculate until the FDR data comes out...
Likely the photographer used a long lens which will foreshorten the apparent wingspan. Note also that the photo was taken from well above the fence so that we are looking a bit down on the wing planform which leads to the perception of even more roll angle.
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Assuming a 5 degree landing attitude, some 737 classics will smack parts on the ground at around 10.5 degrees bank.
I think the margins are better than that.
The following graph gives bank angle for x-wind 30 kt. If we take 140 kts approach, leaving 3 degrees of residual crab, and not fully banking by two degrees,** you only need six degrees of roll to cope with a 30 kt x-wind. And the 737-700 gives a very generous 14 degrees of roll before the flap track or (unlikely) the nacelle touches. And surprisingly, the -800 gives a degree more roll ability, because the approach speeds are higher.
(** The last thing you want is to be slipping into the upwind wheel, as that will result in an alarming gear-twang. Much better to allow a very slight drift downwind, and let the gear touch in 'trailing link' style. So slightly less than full roll is always desirable.)
Last edited by silvertate; 5th Oct 2015 at 18:05.
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@silvertate The quotation was:
The -700/-800 aren't classics. On the -400 if landing with a flare attitude of 5 degrees nose up, I believe the Flap Track Fairing will hit ground at around 10.5 degree roll angle.
And you can see from your chart, assuming the ~132 kts vref with zero crab angle at 30 knots you need to be at point "A" which is just shy of 9 degrees bank. Very tight margin!
Assuming a 5 degree landing attitude, some 737 classics will smack parts on the ground at around 10.5 degrees bank.
On the -400 if landing with a flare attitude of 5 degrees nose up, I believe the Flap Track Fairing will hit ground at around 10.5 degree roll angle.And you can see from your chart, assuming the ~132 kts vref with zero crab angle at 30 knots you need to be at point "A" which is just shy of 9 degrees bank. Very tight margin!
