http://www.youtube.com/watch?v=SRFtBVllxgg
Bus drivers, what caused this?
Trying to bring the nose up to soften the secondary touchdown or does spoiler deployment cause such a big pitch-up moment?
Tailstrike or no tailstrike?
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Lost in Saigon
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Probably because it doesn't need one if flown properly.I wonder why the A320 doesn't have a tail skid like the 727 has.
Tail skids are often the manufacturers answer to an increased likelyhood of a tail strike. You will notice that most designs start with a medium length fuselage and sometime later the manufacturer and/or the airlines see it fit to have a larger capacity a/c with minimal crew and maintenance retraining (and reduced development costs).
This is acomplished by fitting fuselage plugs ahead and behind the wing (for CG purposes), beefing up the gear structure, brakes, etc. Often the wing will stay aerodynamically unchanged.
You will notice that now you have more plane behind the gear so rotating to the same attitude as before will cause the tail to be much closer to the ground.
Since redesigning the gear to make it higher is impractical you have two options. The first one is to learn to live with the lower ground clearance by beating into the pilot's head the proper tailstrike avoidance technique and instaling a tail skid for those "barely there" scrapes.
Your seceond option is to increase Vr and Vref speed so that the angle of attack required for liftoff/touchdown is smaller therfore maintaining tail clearance. Problem with that option is that bigger planes might exclude themselves from some runways due to balanced field requirements (higher Vr = longer runway) You can play with flap settings as well.
You will see this on 752 vs 753, 763 vs 764, 772 vs 773, 733 vs 778
Now the tailskid is mostly for tail protection during takeoff in case you experience premature rotation due to bad CG, trim, dyslexic FO calling Vr too soon, too much/fast rotation. It will provide some protection during landing but don't count on it. It's not as beefy as it looks and you can't win with kinetic energy. (let's skip the part about which point the plane will rotate around as the gear unloads)
I was a passenger on 727-200 sitting in the back when it had a tail strike during a recovery from a bounce. Siting in the back I clearly heard it but it did NOT feel like a hard landing yet the tailskid was driven back into the fuselage grounding the plane for a few days of sheet metal work. I bet you that Aviacsa on the pic had some damage. Coincidently I hear that it's possible to touch the runway with the exhaust of some hushkited 727... Oh and IIRC the 727 had a tail skid from the begining for that very reason... exhaust protection.
Cheers!
