AD 2002-11-03: Air Tractor, Inc. Models AT-502, AT-502A, AT-502B, and AT-503A Airplanes

This AD applies to certain Models AT-502, AT-502A, AT-502B, and AT-503A airplanes. Use paragraph (a)(1) of this AD for airplanes that do not incorporate and never have incorporated winglets. Use paragraph (a)(3) of this AD for certain AT-500 series airplanes that incorporate or have incorporated Marburger Enterprises, Inc. winglets. (1) The following presents airplanes (certificated in any category) that are affected by this AD, along with the new safe life (presented in hours time-in-service (TIS)) of the wing lower spar cap for all affected airplane models and serial numbers: Model Serial Nos. Safe life AT-502 0003 through 0236 2,050 hours TIS. AT-502A 0158 through 0618 1,650 hours TIS. AT-502B 0187 through 0618 2,050 hours TIS. AT-503A All serial numbers beginning with 2,050 hours TIS 0067. (2) If piston powered aircraft have been converted to turbine power, you must use the limits for the corresponding serial number turbine-powered aircraft. (3) The following presents airplanes (certificated in any category) that could incorporate or could have incorporated Marburger Enterprises, Inc. winglets. These winglets are installed in accordance with Supplemental Type Certificate…