The passenger of the Cessna 182 reported that he and the pilot had been flying around the Pacific Northwest for several days. On the evening of June 11, 2023, they arrived at McCall Municipal Airport (KMYL) in Idaho and stayed overnight. Due to forecasted weather they elected to depart the following morning for a short flight to Indian Creek, Idaho.
The passenger reported that the pilot conducted a preflight inspection of the airplane and pre-takeoff checks on the morning of the accident. During the taxi to the runway, the pilot commented on the slight tailwind for the departure runway, and that it may result in a slightly longer takeoff roll.
As the airplane rotated for takeoff, the pilot said, “We have a power problem.”
The passenger told investigators that the pilot stated that he wanted to return to the runway to land, but the airplane was not climbing and did not have enough altitude to fly over the trees at the departure end of the runway.
Witnesses who observed the airplane departing to the north from KMYL noted that the departure roll appeared to be “unusually long.”
One witness reported that, “the engine was not developing too much power, but it sounded smooth, very low power, no coughing or sputtering….”
From their vantage point, they saw the airplane’s nose pitch up and begin to climb, but it did not gain enough altitude to clear the trees that were near the departure end of the runway.
The airplane hit the top of a pine tree before it descended below the tree line and out of visual range.
The pilot died in the crash and the passenger was seriously injured.
A post-accident examination of the engine revealed that a single-drive dual magneto was installed. The magneto was located in its normal relative position on the mounting pad, however it was not securely attached to the mounting pad.
Both the upper and lower retaining hardware were loose, and the lower retaining hardware was also backed off from the magneto. When the magneto was manually manipulated, there was movement between the mounting pad and the magneto.
A review of the airplane’s maintenance records revealed that a single-drive dual (D-style) magneto had been replaced about 15 hours before the accident flight.
The maintenance facility that replaced the magneto reported that the airplane was brought in for service due to a possible malfunctioning magneto.
According to the mechanic, while he was troubleshooting the malfunction, he noted that the “P” leads were crossed. The “P” leads were switched to their proper positions. An engine run was conducted, confirming that the right side of the magneto had failed.
The mechanic told investigators that the maintenance facility was only able to perform limited to basic diagnostic testing and replacement of magnetos, and that his experience with a D-style magneto was limited. As a result, the airplane owner ordered and supplied another single-drive dual magneto to the maintenance facility. After installing the replacement magneto, several engine runs were conducted, with no further discrepancies noted. A separate mechanic conducted the quality control check of the maintenance performed.
The airplane was returned to service and the pilot was advised to conduct a run-up and in-flight ignition test. If any abnormalities were present during the run-up and in-flight ignition test, the pilot was to return the airplane to the maintenance facility for further troubling shooting and diagnostics. The pilot conducted a run-up of the airplane, completed a couple of circuits in the airport traffic pattern, and then departed the area.
A service instruction letter issued by the engine manufacturer provided guidance for the installation and maintenance of the single-drive dual magneto. The service instruction letter cautioned that the magneto and/or attaching hardware on the engine accessory housing can become loose or unfastened after maintenance.
This condition can be caused by any, or a combination, of the following: Incorrect fastening hardware installation, incorrect torquing of the fastening hardware, incorrect gasket used for the magneto installation, incorrect magneto clamps installed, and incorrect gap between the magneto clamp and the accessory housing. The letter noted that failure to comply with the service instruction could result in a loss of engine power.
Probable Cause: Maintenance personnel’s failure to properly torque and inspect the magneto hardware, which resulted in a partial loss of engine power.
NTSB Identification: 192360
To download the final report. Click here. This will trigger a PDF download to your device.
This June 2023 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
