EK407 Tailstrike @ ML

[RetiredBA/BY]

I don't normally get involved on these theads, just a watcher being long retired, but I can't let this on go. When I flew Valiants we had a check time to 100 knots to make sure accel. was OK. If speed was down we aborted, did once, we went off the end, slowly. That check might well have saved Emirates at MEL.

When I converted to civil jets, BOAC VC10s I was surprised that no such check existed, however, it was BOAC so surely they knew best. Some years later as a B737 Capt. I got involved in designing a TOPIS, Take Off Performance Indicator System, it got shelved, not needed, too hard box. The electronics then were not as they are now.

I see no reason why when the performance of a sophisticated electric jet such as an A340, say, is calculated the FMC cannot calculate exactly what the accleration rate should be, considering all parameters such as thrust, temp. flap setting, weight and runway characteristics, and assign THAT rate to one pointer on a scale, on , say, the HSI or ADI The exact acceleration could then be extracted from the IRSs and another pointer driven alongside the other (rather like Concorde's speed/C of G pointers) so a direct comparison could be made between planned accel. and achieved accel. to say, 100k. Should be easy to do AND interpret.

On too many aircraft, certainly those that I have flown, we ASSUME, but do not know, that the tyres (and therefore brakes) are all intact and that the brakes are all cool, and able to accept the energy of a rejected take off at V1.

How many flight manuals contain data on tyre limitations, (although speeds such as TSOC62, 225 mph. if I rememenber correctly are indicated on the tyre mouldings) such as the maximum taxi distance at given weights before the tyres overheat to the risk of possible failure ?

Many years ago I wrote a paper for the International Journal of Flight Safety (only one edition published before the publisher died).

In that I questioned why it was not an airworthiness requirement for ALL jet transports to be fitted with brake temp. guages (sure indicator of a dragging brake as I experienced once on a VC10, ) and tyre failure indicators (like Concorde and even on my BMW) which tells me I have lost one tyre and TWO brakes assuming I want to brake in a straight line. (which I did once in a 737, fortunately during push back when a brand new wheel casting failed).

Does the A340 have brake temp. guages and tyre failure indicators, and what else could cause it to fail to become airborne on a 12,000 feet runway, even at max. gross, except too little thrust or a totally wrong flap setting, assuming the crew (of 4) would have immediately spotted gross overloading or an unexpected large tailwind ?


I believe the lack of information about take off acceleration is one of the last missing pieces in the aviation safety jigsaw, and SO easy to correct with modern electronics. Any constructive comment ?

PS Sorry if I have not used correct AB terminolgy, spent a long time on Boeings, 73, 75, 76, never flown a 'bus.