According to the flight instructor, the preflight inspection and engine run-up of the Cirrus SR22T were normal. During takeoff from the airport in Boerne, Texas, about 20 to 30 feet above the runway, a CAS message for fuel flow illuminated. The engine immediately began “sputtering” and did not provide sufficient power to climb.
The CFI attempted to land the airplane on the remaining available runway, but was unable to stop before it departed the runway and hit a fence, resulting in substantial damage to both wings.
Cirrus Mandatory Service Bulletin SB2X-42-18R3, issued Sept. 12, 2019, includes a software change to include a CAS message for fuel flow in excess of 42 gph.
The Cirrus SR22T Pilot’s Operating Handbook states, in part: “Excessively high fuel flows may lead to a loss of engine power and may cause the engine to fail. If fuel flow exceeds 42 gph, maintenance is required.”
A review of onboard data revealed that fuel flow to the engine peaked at about 45 gph on the accident flight.
Post-accident examination of the airplane and engine was performed. The engine was started and idled around 1,200 rpm to bring it to operating temperatures. The power lever was moved to the full forward position and the fuel flow immediately increased to about 44 gph and the manifold pressure increased to about 37 inHg. The engine began to run rough and black smoke was observed from the exhaust. The power lever was brought back to 1,000 rpm and the engine was shut down. No other anomalies were found during the engine run.
A review of maintenance logs revealed that the airplane had undergone a 100-hour inspection on June 7, 2024, 15 flight hours before the accident. The maintenance logs indicate that, during the inspection, the mechanic performed engine set up in accordance with Cirrus SR22T Airplane Maintenance Manual (AMM) 73-20 and Continental Motors Maintenance Manual M-18. An operational check was performed with no discrepancies noted by the mechanic.
M-18 references the use of Continental Motors Maintenance Manual M-0 for engine inspection and service, including an engine operational checklist. However, the mechanic was unable to provide documentation of the operational check, including the unmetered fuel pressure, manifold pressure, fuel flow at 2,500 rpm, or the idle rpm rise as should have been recorded per the AMM.
The airplane’s remote data module was sent to the NTSB Vehicle Recorders Laboratory for data recovery. The data revealed that the fuel flow reached at least 42 gph on several previous flights.
According to a flight instructor who had previously flown the airplane, he received an indication for a fuel flow anomaly each of the four times he flew the airplane. The instructor added that the high fuel flow was known to be a common issue with the airplane.
However, the flight instructor who was flying the airplane on the accident flight said he was not made aware of the fuel flow anomaly.
The purchaser of the airplane after the accident reported that he found the fuel flow was set too high and that he adjusted it before flight. Following the adjustment, the airplane operated on a 1,000-mile flight with no anomalies reported.
Probable Cause: Maintenance personnel’s inadequate adjustment of fuel flow, which resulted in an excessively rich mixture, a rough-running engine, and a subsequent partial loss of engine power.
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This June 2024 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.
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