FlightFollowerBeech A36 N19MT — Dead Cylinder, Oil Pressure Loss and Engine Failure
The Flight & Context
On January 19, 2023, a Beech A36, N19MT, was conducting an IFR personal flight from New York toward Ohio when the aircraft developed degraded climb performance. The pilot and one passenger were aboard. The NTSB investigation found that the eventual loss of engine power resulted from a failure of the No. 4 piston and the subsequent loss of engine oil.
The Engine Warning Signs
Recorded engine data showed the No. 4 cylinder-head temperature exceeding its highest allowed value shortly after takeoff. The temperature later fell in a pattern consistent with the cylinder no longer firing correctly. The flight continued while the engine problem developed.
The Emergency Sequence
At about 17:18:30, the pilot reported a dead cylinder and requested to proceed toward Westchester County Airport. ATC issued a 340-degree heading, but the aircraft did not immediately follow it. At 17:20:11, engine data showed oil pressure falling below the specified minimum and continuing toward zero.
The pilot eventually turned toward the assigned heading and later declared an emergency, reporting that the oil pressure was dropping. A subsequent uncommanded right turn increased the distance and flight time to the intended runway. The controller issued another vector. The engine then lost all power, and the aircraft descended toward the airport before striking trees and terrain less than one mile from the runway threshold.
What the Investigation Found
The NTSB found damage to the No. 4 piston consistent with pre-ignition or detonation. The damage pressurized the crankcase, pushed oil out through the breather system and depleted the oil supply, ultimately causing catastrophic internal engine failure. Investigators could not determine the underlying reason for the pre-ignition/detonation.
Probable Cause
The NTSB determined that the probable cause was pre-ignition/detonation damage to the No. 4 piston for reasons that could not be determined, which caused crankcase pressurization, oil exhaustion and catastrophic internal engine failure.
Key Takeaways / Lessons Learned
The case demonstrates why engine trend information can matter before a complete power loss. A rising cylinder temperature, degraded climb performance and a reported dead cylinder were separate warning signs of a deteriorating engine condition. Once the emergency developed, minimizing delay and preserving the most direct path to a suitable runway became critical.
What happened
On the evening of January 19, 2023, a privately flown Beech A36 Bonanza, registration N19MT, crashed into trees near North Castle, New York, at about 5:29 p.m. local time. The pilot and the one passenger on board were both killed, and the aircraft was heavily damaged. It was a personal flight operating under instrument flight rules.
The trouble showed up early. Roughly 18 minutes after departure the pilot asked air traffic control for a lower altitude, explaining that the Bonanza was climbing poorly. A short time later he told the controller he had a “dead cylinder” and asked to divert to a nearby airport, Westchester County. The controller gave him a heading toward it, but the pilot took more than two minutes to actually turn onto that heading.
From a rough engine to a forced landing
When the aircraft was about 6 nautical miles from the airport, the pilot declared an emergency and reported that his oil pressure was falling. After finally turning toward the airport, the Bonanza drifted into a right turn that the controller had not asked for and the pilot never mentioned. The controller told him to level the wings and hold 5,000 feet.
That unplanned turn cost time. Because the heading had changed, the controller had to issue a fresh vector, which added distance to the runway. Flight data shows the engine then stopped producing power altogether. The Bonanza kept descending and hit trees and the ground less than a mile short of the runway it was trying to reach.
What the engine data showed
The recorded engine data tells a story that started almost at takeoff. Only about a nautical mile past the end of the departure runway, the cylinder head temperature on cylinder No. 4 climbed past its maximum allowed limit, and kept climbing as the flight continued. Then the reading began to fall, which is what you would expect when a cylinder stops firing. The flight carried on regardless.
Investigators who took the engine apart found damage on the top and sides of the No. 4 piston. That pattern points to pre-ignition or detonation, where the fuel-air mixture burns uncontrollably. The resulting pressure in the crankcase forced oil out through the breather, and the engine gradually ran out of oil until it failed internally.
Both spark plugs in that cylinder were heavily fouled with deposits. One had a broken piece of its insulator and the other had a cracked insulator, but investigators couldn't tell whether that damage caused the detonation or resulted from it.
Ruling out the usual suspects
Detonation usually has a short list of causes: ignition timing that is off, very hot intake air, an overheating engine, carbon or oil in the combustion chamber, poor fuel, or a mixture set too lean. Investigators could not measure the magneto timing after the crash, but they found nothing wrong with the magnetos or the ignition wiring. Hot intake air, general overheating and carbon or oil contamination were judged unlikely or were not seen. The fuel supplier reported no problems with the fuel it had provided.
How the pilot had the mixture set is unknown. However, investigators considered it unlikely that he would have leaned the engine so far that the cylinder overheated, since that would go against the aircraft's published limits and takeoff procedures.
Why this case matters
The timeline above shows how much time passed between the first warning and the emergency. The pilot reported degraded climb performance at 17:16, called out the dead cylinder at 17:18, and told the controller he was not declaring an emergency at 17:19. He declared one only at 17:21, after the oil pressure had dropped below 30 psi. The Mayday came four minutes after that, and the engine stopped seconds later.
A cylinder that stops firing on a single-engine aircraft is often the first sign of a much bigger problem. Declaring an emergency early gives controllers the freedom to offer the most direct route, and it keeps the aircraft as high and as close to a runway as possible. In this case every delay, from the late turn to the uncommanded right turn and the new vector, added distance that the failing engine couldn't cover.
Research and reconstruction
Flight Follower Editorial Team
This reconstruction was researched from official investigation records where they exist, the original air traffic control recording, and contemporary reporting. The aircraft movement, timeline and written account were assembled independently by Flight Follower. Where an investigation is open or no probable cause has been published, the account says so rather than offering one.
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Accident Facts
- Incident date
- 19 Jan 2023
- Registration
- N19MT
- Category
- Emergency, Crash, Fuel, Engine failure
- Reconstruction
- 9:35
Sources
Primary Source / Investigation Record
Primary Investigation Reference
NTSB accident number: ERA23FA113
Primary investigation report: ERA23FA113