Airworthiness Directive · Amendment 39-16478 · Wings
Cessna Aircraft Company (Cessna) Models 336, 337, 337A (USAF 02B), 337B, M337B (USAF 02A), T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, 337G, T337G, 337H, P337H, T337H, T337H-SP, F337E, FT337E, F337F, FT337F, F337G, FT337GP, F337H, and FT337HP Airplanes
This AD applies to Cessna Aircraft Company (Cessna) Models 336, 337, 337A (USAF 02B), 337B, M337B (USAF 02A), T337B, 337C, T337C, 337D, T337D, 337E, T337E, 337F, T337F, 337G, T337G, 337H, P337H, T337H, T337H-SP, F 337E, FT337E, F 337F, FT337F, F 337G, FT337GP, F337H, and FT337HP airplanes, all serial numbers, that:
(1) Are certificated in any category; and
(2) Are or have ever been modified by Aviation Enterprises Supplemental Type Certificate (STC) SA02055AT, SA02056AT, SA02307AT, or SA02308AT.
We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires inspecting the wings for internal and external damage, repairing any damage found, installing an operational limitation placard in the cockpit, adding limitations to the flight manual supplement, and reporting the results of the inspection to the FAA if damage is found. This AD was prompted by a wing overload failure and by reports of cracks in the upper wing skins on certain Cessna airplanes that are or have ever been modified by Aviation Enterprises Supplemental Type Certificate (STC) SA02055AT, SA02056AT, SA02307AT, or SA02308AT. We are issuing this AD to detect and correct damage in the wings and to prevent overload failure of the wing due to the installation of the STCs. Damage in the wing or overload failure of the wing could result in structural failure of the wing, which could result in loss of control.
Comply with this AD within the compliance times specified, unless already done.
Before further flight after November 3, 2010 (the effective date of this AD), do a general and focused inspection of the wing for internal and external damage from wing station (WSTA) 23 to the wing tip. Repetitively thereafter inspect every 100 hours time-in-service (TIS) or every 12 calendar months, whichever occurs first, for as long as any of the STCs specified in paragraph (c) of this AD are installed. If at any time the STCs are permanently removed, one final inspection is required following removal. Do the inspections following Appendix 1 of this AD.
(h) Anytime severe and/or extreme turbulence is encountered during flight, before the next flight, do a focused inspection of the wing for damage following steps 1, 2, 3, 4, 7, and 10 in Appendix 1 of this AD. Also inspect for signs of distress in the upper front spar in the area around WSTA 177. The definition of severe and extreme turbulence can be found in Table 7-1-9 of the FAA Aeronautical Information Manual (AIM). You may obtain a copy of the FAA AIM at http://www.faa.gov/air_traffic/publications/atpubs/aim/.
(i) For airplanes specified in paragraph (c) of this AD that are modified by STC SA02055AT or SA02308AT (wing extensions with fuel provisions), before further flight after November 3, 2010 (the effective date of this AD), do the following:
(1) Incorporate the information from Appendix 2 of this AD into the Limitations section of the Aviation Enterprises Aircraft Manual Supplement.
(2) Fabricate a placard (using at least 1/8 -inch letters) with the following words and install the placard on the instrument panel within the pilot's clear view: “MTOW=4,700 LBS. MAINTAIN AT LEAST 12 GAL OF FUEL IN EACH WING TIP FOR AIRPLANE WEIGHTS ABOVE 3,300 LBS.”
(j) For airplanes specified in paragraph (c) of this AD that are modified by STC SA02056AT or SA02307AT (wing extensions with no fuel provisions), before further flight after November 3, 2010 (the effective date of this AD), do the following:
(1) Incorporate the information from Appendix 3 of this AD into the Limitations section of the Aviation Enterprises Aircraft Manual Supplement.
(2) Fabricate a placard (using at least 1/8 -inch letters) with the following words and install the placard on the instrument panel within the pilot's clear view: “MTOW=4,000 LBS, MAX MANEUVER=2.5 G, Va=100 KCAS, Vno=105 KCAS, Vne=135 KCAS. OPERATION RESTRICTED TO VFR”
(k) Before further flight after each inspection required in paragraphs (g) and (h) of this AD where damage or signs of distress are found, repair all damaged and distressed parts following FAA Advisory Circular (AC) 43.13-1B. You may obtain a copy of AC 43.13-1B at http://rgl.faa.gov/.
(l) Within 10 days after each inspection required in paragraphs (g) and (h) of this AD in which damage or distress is found, send a report to the FAA at the address specified in paragraph (o) of this AD. Include as much information as possible, including the “N” number, model number, serial number, list of STC modifications, TIS on the aircraft and wing extension, description of the damage (location, length, orientation, parts cracked, sketches, etc.), and if possible, pictures of the damage.
(m) For all airplanes specified in paragraph (c) of this AD that have STC SA02055AT, SA02056AT, SA02307AT, or SA02308AT permanently removed, do one final inspection as specified in paragraph (g) of this AD, take corrective actions as specified in paragraph (k) of this AD, report the results as specified in paragraph (l) of this AD, and remove the flight limitations specified in paragraphs (i) and (j) of the AD. No further action is required.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
