The point raised about perceiving rate of acceleration at night is a valid one, especially I suppose when the flight deck is as high it is on a 747.
Something to consider:
The captain of a Hercules decided to abort at Stansted because he felt that the aircraft's acceleration was somewhat slower than normal. After clearing the runway, tower advised him that flames could be seen in the main gear area. The crew evacuated and the fire was subsequently extinguished. I doubt if the aircraft was 'pulling' left or right unnoticed during taxy out, or take-off, but a brake only has to be binding slightly to build up heat. The abort was conducted at a fairly low airspeed (80kts I think) and probably very little brakes were required. This incident occured at night and with a relatively light load. If he had continued and the landing gear been retracted...
So, my question is, if a 747 had a brake binding in one of the centre bogies, would this have been noticeable on taxy out or take-off, apart from maybe more thrust being required depending on the amount and point at which it started binding - maybe at brake release for the take-off roll? Does this model 747 have brake temp. indicators, and if so does the MEL specify a requirement for them to be serviceable for all departures? The Herc has brake temperature indicators - they are fitted to the back of the FE or pilot's hand. Always a good idea to check to see if a single wheel is cooler or hotter than the other three after landing - it can tell you a lot about the state of the brakes.
Edited for clarity (or not).
Last edited by fourpaddles; 23rd Oct 2004 at 14:10.