atpl question
Can anyone tell me the effect that a change in altitude will have on an aeroplane's TAS? I have a question which is as follows:
An aeroplane performs a straight and level horizontal flight at the same angle of attack at two different altitudes: (all other factors of importance being constant, assume ISA conditions and no compressibility effects)
A – the TAS at the higher altitude is higher
B – the TAS at both altitudes is the same
C – the TAS at the higher altitude cannot be determined
D – the TAS at the higher altitude is lower
Ref: AIR: atpl, cpl;
Ans: A
Is the answer above correct? If so please elaborate.