FAA disapproves certain adhesives

The FAA notice "encourages aircraft owners, operators," and others in the maintenance and supply industries to inspect certified aircraft and parts inventories to determine if one of the 12 products made by a small California company was on hand, or installed on certified aircraft. In such cases, "the FAA recommends that they be removed and quarantined until a determination can be made regarding their eligibility for installation."

A Federal Register search found no airworthiness directives or other documents related to the notice. The September 13 unapproved parts notice names Aircraft Spruce as the vendor that sold the various adhesives subject to the FAA investigation. Rob Irwin, vice president of marketing at Aircraft Spruce and Specialty Co., provided a statement via email:

"Aircraft Spruce had been a distributor of Certified Coatings for decades before the product line was acquired by PTI," Irwin wrote, referring to the adhesives made by Products Technologies Inc., the California company cited as the original manufacturer in the FAA notice. (PTI was a family-run business that has since been sold to new owners.) The parts manufacturer approval (PMA) required for adhesives to be used on certified aircraft would have originated with a prior manufacturer that was acquired by PTI.

"Aircraft Spruce was not informed by PTI that the PMA for these products was affected by the transition of the product line from Certified Coatings to PTI. As a distributor of a wide selection of aviation products, Aircraft Spruce relies on the manufacturer to [ensure] that all applicable FAA approvals are in place and current," Irwin wrote.

It is unclear how many aircraft may be affected, though the number is likely small. The various adhesives cited by part number are mostly types of butyrate dope that vary by color, as well as two varieties of clear nitrate dope, also used to secure fabric covering on aircraft, a process that has become increasingly rare over the decades since the products were first sold. Experimental aircraft owners were not asked to supply information to the FAA, while those to whom the notice was addressed—including owners of certified aircraft—were asked to contact the FAA to report findings.

"In addition to the above recommendations, the FAA would appreciate any information concerning the discovery of the above identified part numbers from any source, the means used to identify the source, and the actions taken to inspect and/or remove the part numbers from FAA type-certificated aircraft and/or associated aircraft parts inventories," the agency wrote. The notice originated from the FAA Los Angeles Certificate Management Section, 3960 Paramount Blvd., Lakewood, California, 90712; the phone number 562-627-5290 was provided.

Aircraft Spruce is a longtime AOPA Strategic Partner.