Compass turning errors

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Compass turning errors

Postby Doss79 » Sun Feb 28, 2010 9:33 am

I can't find it on the PTS nor the sport pilot knowledge material from KING SCHOOLS, but does anyone know if it's possible that the DPE can test me on compass turning errors (deceleration/acceleration) for the checkride?

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One of 9

Postby bryancobb » Wed Mar 03, 2010 9:58 am

Hey Doss,

The wiskwey compass falls in the "avionics" area.

In the PTS, F-8, Systems/Avionics, it is one of the 9 subject areas that the examiner has to pick from. The examiner only has do do 3 of the nine.

Most examiners will probably want you to demonstrate that you have a pretty fair understanding of the weaknesses of the magnetic compass, during your oral.

They are probably going to want you to follow a course on your cross country using the compass in straight and level, unaccelerated flight.

They will not expect you to know a lot about or demonstrate turns to headings using the compass.

The Pilot's Handbook of Aeronautical Knowledge (free at FAA website) gives you a good understanding of all you'll need to know about the magnetic compass.
Bryan Cobb
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Commercial/Instrument Airplane
Commercial Rotorcraft Helicopter
Manufacturing Engineer II, Meggitt Airframe Systems, Fuel Systems & Composites Group
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Postby Doss79 » Thu Mar 04, 2010 9:01 am


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Postby Paul Hamilton » Sat Apr 03, 2010 2:14 pm

Typically the compass turning errors would be covered in the oral to test the aeronautical knowledge as Bryan states above. By the time you are ready to fly, the examiner usually will have covered compass errors. For flight, the tolerances for maneuvers such as steep turns, I like to use landmarks such as roads to eliminate any compass errors. The headings for pilotage and diversion can be done with a compass or a GPS.

If an examiner asks to turn to heading 180, and you have a magnetic compass plus a GPS with true heading, ask if he/she wants true or magnetic so there is no confusion as to the task.
Paul is a Sport Pilot CFI/DPE and the expert for ASA who writes the books and produces the DVD's for all pilots flying light sport aircraft.
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