Welcome Back

Sign in to your PART66Online account

One click — no password needed

or use email
Forgot password?

Don't have an account? Register here

An aircraft is on course on an ILS Localiser. What is the depth of modulation?

  • zero
  • 20%
  • 50%

Explanation from PART66Online

The localiser radiates 90 Hz and 150 Hz tones; when the aircraft is exactly on the centreline both are received equally, so the difference in depth of modulation (DDM) is zero. A non-zero DDM only appears as the aircraft moves off the runway centreline towards one side.

N

nairs asked · 18 Mar 2014

depth of mod zeroooo??

Community Comments (3)

A
alarlns 30 Mar 2014
20% is right
A
alarlns 10 Apr 2014
I think that what was meant to be asked in this question is the difference of modulation of 150 Hz and 90 Hz tone if the aircraft was on the the center line. If the aircraft was on course on a ILS Localizer, then the difference in depth modulation on is zero.
J
Jordi 9 Apr 2021
Guys it says on the books of my part15 organisation,that when the a/c in on couse with the localizer there is no depth and thus 0 modulation.

Please Sign In to post a comment.

We use essential cookies to keep you signed in, plus anonymous analytics to understand how the site is used. Cookie-based analytics is set only with your consent. See our Privacy & Cookie Policy.