Precision Airmotive Tackles Fuel-Injection Servo Problem


If a brass hex plug is loose on your Precision Airmotive fuel control, don’t fly your aircraft until the issue is resolved. Two incidents relating to RSA-10ED1 fuel-injection servos on Lycoming IO-540-K engines in Piper Saratoga/6X aircraft have led Precision Airmotive to call for immediate action. A brass hex plug has been found in two cases with damaged threads and hanging from its safety wire, out of its hole. One incident resulted in an off-airport landing that considerably damaged the involved aircraft. In each case, the servos had between 200 and 300 hours time since new. While the cause of the problem has not yet been confirmed, Precision Airmotive believes immediate action is warranted and is requiring immediate inspection of all aircraft with RSA-5 or RSA-10 servos “which have had a new, rebuilt, overhauled, or repaired engine and/or servo installed since August 1, 2006 to determine if the brass regulator plug is loose.” A visual inspection isn’t good enough.

“The inspection should be accomplished by attempting to turn the plug by hand, while taking care not to damage the safety wire or seal,” according to the company. If the plug is loose, contact Precision Airmotive at 360-651-8282 and do not fly the aircraft until the issue is resolved.