@ btommy
Thanks.
The below are some questions from Oxford instrumentation book - objective revision 4 and 5.
Q1) An a/c is descending at a contant mach number. If the a/c is descending through an inversion layer, the RAS will:
a)remain constant
b)increase
c)decrease
d)decrease then decrease more slowly
Answer is b) increase.
however during descent in inversion, temp decreases at lower altitude. so, LSS decreases. since M.no = (TAS / LSS), therefore TAS should also decrease, in order for M.No to remain constant.
Yes, density increases at lower altitudes.
Now, RAS=(1/2)*density*(TAS squared).
Therefore effect of decreasing TAS is more, then increase of density.
so answer should be c) decrease.
Can anyone explain?
Q2)A perfectly frictionless DI, is corrected to give zero drift on the ground at 30 degree north. The DI is set to read 100 degree in an a/c stationary on the ground in latitude 45 degree north. The reading after 45 mins will be:
a) 92.33 degree
b)102.50 degree
c)97.78 degree
d) 103.75 degree
Q3) with constant drift during flight, the a/c heading will:
a)increase by more than 10 degree
b)decrease by less than 10 degree
c)increase by less than 10 degree
d)remain constant
Answer is b). what;s the logic?