a) 000; 000 with needle central and TO indicated
b) 090; 090 with needle central and FROM indicated
c) 000; 000 with needle central and FROM indicated
d) 090; 090 with needle central and TO indicated
Just cant visualize this one.
Q.2. The accuracy of a DME:
a) is approximately ±0.5nm
b) decreases with increase of range
c) increases with increase of altitude
d) is approximately ±2 nm
Also interested in these questions.
I'm struggling to understand the first I'm afraid. Surely if the VOR is East of your position you will be on the 270 radial and would need a 090/270 OBS selection to get "to" or "from", respectively. Why would you ever get a reading of 000? Is this talking about a relative bearing?
What does 'correctly tuned' mean. Are you tracking inbound or outbound to the beacon?
Second question, if we know the required accuracy of a DME is 1/4nm + 1.25%, we know A and D are wrong.
C is wrong (accuracy decreases with increase in altitude as the vertical 'slant' component increases), so we are left with B as the least worst option. It's true to say slant accuracy increases with range but then DME is line of sight so eventually accuracy will decrease with an increase in range, as you pass beyond line of sight of the transmitter.