N747MLCessna 177RG · 1975

On October 18, 2022, about 0740 Pacific daylight time, a Cessna 177RG, N747ML, was substantially damaged when it was involved in an accident near Mesa, Arizona. The pilot sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The pilot stated that Falcon Aviation Services, based out of Falcon Field Airport (FFZ), Mesa, Arizona, reinstalled the overhauled engine and signed off the engine logbook entry on October 12, 2022. After multiple ground runs, the pilot completed an uneventful post-overhaul flight.

The pilot reported that he departed on the accident flight about 0624 with 28 gallons of fuel onboard and maneuvered north of FFZ, where he flew about one hour orbiting about 4,000 ft above the ground at 65% to 75% engine power. The pilot returned to FFZ and was turning the airplane from base to final for runway 04R when the engine lost total power. The pilot attempted to restart the engine but was unsuccessful, and he conducted a forced landing into a water canal. The airplane impacted a berm and came to rest in the canal, resulting in substantial damage to the left wing, fuselage, and engine mount. (See figure 1.) During the recovery of the airplane, about one cup of fuel was recovered from each fuel tank.

Figure 1. Google map view of wreckage location in relation to FFZ Runway 04R, with embedded picture of accident airplane in water canal.

Postaccident examination of the airframe and engine revealed that the fuel supply line from the fuel injection servo to the fuel flow divider, which attached to the baffle union fitting, exhibited a surging fuel leak when the propeller was manually rotated. Fuel continued to surge from the fuel line fitting as the engine-driven fuel pump actuated with the continuous manual rotation of the propeller. It was determined that the fuel line B-nut (figure 2) was not secured and was able to be turned ½ revolution to “finger tight.” The fuel pump, fuel flow divider, and each corresponding fuel line was secured to its respective mounting pad or fuel system component.

Figure 2. View of fuel supply line from fuel servo with overlayed close-up view of baffle union fitting connection (photo courtesy of engine manufacturer)

According to the repair station, there were two primary installers of the accident engine, a technician and an inspector. The recovered task card for the engine installation revealed that the fuel system tasks, including a fuel leak check, were completed and signed off by both the technician and the inspector; however, it could not be determined which individual secured the fuel line to the baffle union fitting.