Airworthiness Directive · Amendment 39-15150 · Fokker Model F27 Mark 050 Airplanes Equipped With Dowty Type R.352 or R.410 Series Propellers
Fokker Model F27 Mark 050 Airplanes Equipped With Dowty Type R.352 or R.410 Series Propellers
This AD applies to Fokker Model F27 Mark 050 airplanes, certificated in any category; equipped with Dowty Type R.352 or R.410 series propellers.
The FAA is adopting a new airworthiness directive (AD) for certain Fokker Model F27 Mark 050 airplanes equipped with Dowty Type R.352 or R.410 series propellers. This AD requires checking the maintenance records to determine whether Minnesota Mining and Manufacture Co. (3M) 1300L adhesive was used to attach the de-icer assembly overshoes (boots) to the propeller blades, repetitive inspections of affected boots, and replacing boots attached with defective adhesive. This AD results from three events of propeller blade de-icer assembly boots debonding and detaching during flight. This condition was caused by using 3M 1300L adhesive to attach the boot to the propeller blade. We are issuing this AD to detect and correct boots attached with defective adhesive, which could result in debonding and separation of a boot from the airplane, consequent reduced structural integrity of the airplane, and possible injury to passengers and crew.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 30 days after the effective date of this AD: Check the maintenance records to determine whether 3M 1300L adhesive was used to attach the de-icer assembly boots to the propeller blades.
(1) If 3M 1300L adhesive was not used: No further action is required by this paragraph.
(2) If 3M 1300L adhesive was used, or the type of adhesive cannot be determined: Within 650 flight hours, do a general visual inspection for signs of lifting or bubbling of the adhesive in accordance with the Accomplishment Instructions of Dowty Service Bulletin F50-61-158, including Appendix 1, dated September 30, 2005.
(i) If no signs of lifting or bubbling are found: Repeat the inspection at intervals not to exceed 650 flight hours.
(ii) If any signs of lifting or bubbling are found: Before further flight, replace the affected de-icer assembly boot in accordance with Accomplishment Instructions of the service bulletin.
Note 1: For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
As of the effective date of this AD, no person may use 3M 1300L adhesive to attach a boot to the propeller blade, on any airplane.
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.
Propellers
