Morgan MINI-500 N500XM

Summary

On 19 July 1997 at about 19:30 local time, a Morgan MINI-500 registered N500XM was involved in an accident near Ava, Missouri, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

19 July 1997 at 19:30

Classification

Accident

Location

Ava, Missouri, United States

Coordinates

36.9491, -92.6598

Aircraft

Morgan MINI-500

Registration

N500XM

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Cabool → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CHI97LA222

Nobody was injured.

Loss of engine power due to loss of engine cooling fluid. Related factors were maintenance service bulletin not complied with by the owner/pilot mechanic resulting in low output of the carburetor, and unsuitable terrain.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot was completing a series of flight tests that involved transitions from cruise flight into a hover. The pilot reported the exhaust gas temperature (EGT) was higher in cruise flight than when hovering and that the EGT cooled rapidly when the helicopter went from cruise flight into the hovering maneuver. The pilot stated that approximately two miles from his destination, at 2,500 feet mean sea level (msl), he began a 200 to 300 foot/min descent to reach the airport's traffic pattern altitude. He said that as soon as the descent was initiated he experienced unusual engine noises and an abrupt loss of engine power. He lowered the collective and applied full power, but received no indication of engine power. He then initiated an autorotation to landing on a field with a 30-degree slope. Upon landing, the aircraft rolled over and came to rest on its port side causing the rotor to impact the tail boom. Examination of the engine showed evidence that the engine had seized during flight. Inspection of the fuel metering system showed that the accident airplane had not complied with Revolution Helicopter Service Information Letter number 042696, which requires the original factory carburetor jet setting to be adjusted to insure that the EGT be between 1,000 and 1,150 degrees Fahrenheit. No engine coolant was found in the coolant tank and the coolant hose tee was found to be deformed and leaking fluid.

Quoted verbatim from the NTSB record.