Welcome Guest. Sign in or Signup

5 Answers

Why is it called a “Compass Locator?”

Asked by: 27650 views ,
Instrument Rating

Why is it called a compass locator? If I can't locate my compass I really shouldn't be flying IFR!

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

5 Answers



  1. John D. Collins on Nov 19, 2011

    I really don’t know why it is called a Compass Locator.  One of its functions is to provide ADF navigational guidance to the NDB located at the IAF, typically at the  marker beacon location. When you are within the service volume of the NDB, it can provide a means of navigating directly on a random route to the IAF to commence the approach.  So maybe it gets its name from beign able to locate and navigate to the IAF from anywhere on the Compass? Marker beacons and Compass Locators are going away.

    +9 Votes Thumb up 9 Votes Thumb down 0 Votes

  2. Best Answer


    Paul Tocknell on Nov 19, 2011

    Actually, the reason it is called a compass locator has little to do with the compass at all.  It actually comes from the old radio compasses installed on airplanes.  

    Radio Compass

    These were visual type radio direction indicators.  The “compass” doesn’t point to magnetic north but to the direction of the selected radio station.  In the first proposals of what would eventually become an ILS, they set up two markers.   

    You would make sure the compass indictor centered and lose altitude as presribed above.  Pretty rough, but back in the late 30s, this is all they had!  

    Thanks for the question, these are the types of questions I love to answer.

    Paul

    +34 Votes Thumb up 35 Votes Thumb down 1 Votes



  3. Donnie Beene on Nov 21, 2011

    @Paul — thanks for sharing this. Very interesting to know a little bit of navigational history.

    -1 Votes Thumb up 1 Votes Thumb down 2 Votes



  4. Ramius Lai on Dec 12, 2014

    Thank you very much Paul. It helps a lot.

    0 Votes Thumb up 0 Votes Thumb down 0 Votes



  5. Mark C. on Feb 22, 2015

    Awesome!

    I recently taught a class on the ILS in one of my CFI-I classes. Neither I, the instructor, nor the students could explain what the purpose of the compass locator was; only that it was considered supplementary equipment for the ILS.

    All the FAA materials I came across were very vague on the subject.

    Thank you for the information!

    +1 Votes Thumb up 1 Votes Thumb down 0 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.