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Doors to Automatic
28th Dec 2009, 16:47
Well not unsafe but perhaps less safe than their standard-length counterparts?

I was reading again about the less than perfect landing personality of the 737-800 over on the AA Jamaica crash thread (the subject has been covered many times before) and it got me wondering if stretched aircraft are less stable/safe than average.

There seem to be a lot of overrun incidents with the 737-800, which by all accounts is a handful to land.

A lot of hard landings involving the A321.

And of course our old friend the MD-11 which seems to spend half its life pretending it's in Australia!

By contrast incidents involving the A318/319 and 737-500/-600 are almost unheard of.

Proefessional opnions would be interesting, non-professional ones optional ......

Clandestino
28th Dec 2009, 21:22
They might be more handful, but generally they're not unsafe, as long as the operator remembers that stretched one just can't do everything that basic model did.

TheGorrilla
29th Dec 2009, 00:22
safe enough. If a proper structural analysis has been done. Although the same old adage still applies"if it looks right, it flies right". If it's too long and looks like it'll snap into pieces following a heavy landing.... It probably will.

Old Smokey
4th Jan 2010, 11:41
I agree with TheGorilla that it is dependant upon a proper structural analysis being made, which of course it is!:ok:

Speaking generally, any pilot must be aware of the specific limitations of whichever aircraft he or she is flying, and if flying mixed fleets of 'Standard' or 'Stretched' aircraft, remember the stretched aircraft's lesser limitations during rotation upon Takeoff, and flare during Landing.

In many respects the 'Stretched' aircraft is improved upon it's shorter sister. Longer moment arm of Fin and Stabiliser provide improved stability and control response. This longer moment arm of the Fin/Rudder will also provide lower Vmcg/Vmca for identically engined aircraft, leading to performance improvements in minimum V1/Vr/V2 speeds upon takeoff in many cases. (The B777-200ER and B777-300, both with identical engines, illustrates this).

Regards,

Old Smokey