CEN22LA186

The pilot reported that about 10 minutes after departure the engine sustained a partial loss of power. During the forced landing to a gravel road, the airplane’s left wing contacted a tree, which resulted in substantial damage. A postaccident engine test run was performed, and the engine would not produce rated power, so the fuel servo was removed for testing. Functional testing and examination of the fuel servo revealed that it would not deliver fuel to rated specifications due to a self-locking nut being stuck inside the top section of the plug. This resulted in the head idle spring not properly allowing fuel to flow through the ball valve. The engine and fuel servo had both surpassed the manufacturers’ established time between overhauls by 572 hours.

On April 30, 2022, about 0810 eastern daylight time, a Piper PA-32R-301 airplane, N4303P, was substantially damaged when it was involved in an accident near Loogootee, Indiana. The pilot and passenger were not injured. The airplane was operated under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. The pilot reported that he and a passenger departed Huntingburg Airport (HNB), Huntingburg, Indiana, and were en route to Putnam County Regional Airport (GPC), Greencastle, Indiana. About 10 minutes after departure, while in cruise flight at 3,000 ft mean sea level, the engine lost partial power. The pilot performed a forced landing to a gravel road. During the landing, the airplane’s left wing contacted a tree resulting in substantial damage. The airplane was transported to a recovery facility for further examination. After the airplane was recovered, a Federal Aviation Administration (FAA) inspector examined the engine and could not find any anomalies with the engine. An engine functional test run was conducted, and full engine rpm could not be achieved. The fuel servo and fuel flow divider were removed and sent for further examination. Testing of the fuel servo found that it could not deliver more than 22 pounds per hour of fuel, which was less than the rated specifications. Disassembly discovered that the self-locking nut (p/n 2539449) was stuck inside the top section of the plug. This resulted in the head idle spring not properly allowing fuel to flow through the ball valve. The FAA inspector was informed by the mechanic that the fuel servo was overhauled at the same time as the engine, in March 2002, at a total time of 2,011.1 hours. At the time of the accident, the airplane had accrued 4,383.3 hours. Precision Airmotive Service Bulletin PRS-97 revision 2, dated November 22, 2013, established the time between overhaul for all designated fuel system components to be the same as the engine manufacturer or 12 years, whichever occurred first. Lycoming established a time between overhaul of 1,800 hours.