AC 43.9-1E, ADVISORY CIRCULAR: INSTRUCTIONS FOR COMPLETION OF FAA FORM 337 (OMB NO. 2120-0020), MAJOR REPAIR AND ALTERATION (AIRFRAME POWERPLANT, PROPELLER, OR APPLIANCE) (21 MAY 1987)

AC 43.9-1E, ADVISORY CIRCULAR: INSTRUCTIONS FOR COMPLETION OF FAA FORM 337 (OMB NO. 2120-0020), MAJOR REPAIR AND ALTERATION (AIRFRAME POWERPLANT, PROPELLER, OR APPLIANCE) (21 MAY 1987)., This advisory circular (AC) provides instructions for completing Federal Aviation Administration (FAA) Form 337, Major Repair and Alteration (Airframe, Powerplant, Propeller, or Appliance).