Question on HF Radio wave propagation...
Thread Starter
Joined: Mar 2003
Aviation Qualifications: PPL
Posts: 225
Likes: 21
From: London, England
Question on HF Radio wave propagation...
An aircraft is using a night time HF frequency of 5.5 MHz with ATC. The frequency the pilot would expect to use by day is:
a. 3 MHz
b. 12 MHz
c. 15 MHz
d. 18 Mhz
The correct answer is b. I can see why the freq needs to be higher by day but why 12 MHz specifically? Why not 15 MHz or 18 MHz? Is it just that the answer is most likely to be the lowest, higher frequency than 5.5 MHz or is there a relationship I should know about?
Thanks in advance
9:18
a. 3 MHz
b. 12 MHz
c. 15 MHz
d. 18 Mhz
The correct answer is b. I can see why the freq needs to be higher by day but why 12 MHz specifically? Why not 15 MHz or 18 MHz? Is it just that the answer is most likely to be the lowest, higher frequency than 5.5 MHz or is there a relationship I should know about?
Thanks in advance
9:18
