Some information from an Airbus A340 - 500 FCOM may assist in providing some sober second thoughts and perhaps a pause before contributing some of the inexperienced, uninformed and wilder notions we are seeing.
The following is in no way intended as speculation but only as information.
Tailstrikes on any transport category aircraft have a fairly narrow range of causes. In tailstrike incidents and takeoff accidents, the following have occurred:
- incorrect rotation technique, (early, fast, two-stage)
- incorrect takeoff data calculation, (wrong weights, wrong runway)
- incorrect takeoff data entry, (correct calculation, wrong FMGC entry)
- wrong runway used for takeoff, (taxiway used in some cases)
- incorrect weight and balance numbers, (includes incorrect stabilizer setting)
- incorrect stabilizer setting by the crew (correctly calculated, wrong setting)
- cargo shift, (extremely rare today, but it has happened in the past)
- strong tailwinds/windshear (rare)
Operational Bulletins (not cautionary in nature but expanding upon operations), for the Airbus 340-500 state that, with respect to the A340-300, the flight control laws have been adapted to take into account the longer fuselage length and that the tail clearance is monitored and if marginal, the rotation rate is reduced until lift-off. The information also states, (and this ought to be obvious to anyone), the airplane has a large inertia and the rotation takes time to build up. For rotation, one "sets" the sidestick about 2/3rds back and waits - one does not pull further.
For information, the aircraft does not have a tailskid, but nor do most transports including the B747. The DC8-61 and 63 series did and the B720 had a ventral fin which may have acted as a bit of protection but that aircraft had a very short fuselage compared to the 707.
The Airbus A340-500 rotation technique requires some care. Even though the technique is (or certainly should be) well known/understood by those trained on the airplane, there is specific guidance in the FCOM regarding the maneuver, there remains an aspect to rotation of the Airbus A340-500 that can be a bit of a surprise if one is not prepared for it or knowledgeable about it.
I stress here that this information is for those new on the airplane. This is a non-issue for someone who has been flying the -500 for more than a couple of legs. The FCOM has very specific cautions on rotation technique:
AT VR SPEED
PNF..."ROTATE"
PNF observes the speed and completes the call by VR. When V1 and VR are the same, the calls must be completed by VR.
At VR , the PF initiates the rotation with a positive sidestick input and maintains the positive sidestick input to achieve a continuous rotation rate of about 3°/sec towards a pitch attitude of 12½°
[A343] /15° [A345, A330]. Changes to the sidestick position should not be made until airborne. After lift off, follow SRS pitch command bar. In the event of no FD after liftoff select 12½° [A343] /15° [A345, A330] pitch with all engines (maintain minimum V2 plus 10 kt) or 12½° in the event of an engine failure (maintain minimum V2).
As the rotation maneuver is flown in Direct Law with full authority, pitch control is very sensitive to sidestick inputs. Altering sidestick backpressure can produce pilot induced oscillations and/or may produce a two-stage rotation which significantly increases the chance of tail strike.
Minimize lateral inputs on ground and during the rotation, to avoid spoiler extension. In strong crosswind conditions, small lateral stick inputs may be used, if necessary, to maintain wings level.
If some lateral control has been applied on the ground, the Sidestick should be centralised during rotation so that the aircraft becomes airborne with a zero roll rate demand.
Info
Airbus Training advises that once the rotation has begun, increasing side stick back pressure will increase chance of a tail strike.
CAUTION
In the unlikely event that a tail strike should occur, flight at altitude requiring a pressurized cabin must be avoided and a return to the nearest suitable airport should be performed for damage assessment.