Johnson REVOLUTION MINI-500 N805JJ

Summary

On 26 July 1998 at about 22:00 local time, a Johnson REVOLUTION MINI-500 registered N805JJ was involved in an accident near Shermans Dale, Pennsylvania, 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

26 July 1998 at 22:00

Classification

Accident

Location

Shermans Dale, Pennsylvania, United States

Nearest airport

Haunstein Ultralight Park (0PA2)

Coordinates

40.3309, -77.1898

Aircraft

Johnson REVOLUTION MINI-500

Registration

N805JJ

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Klingerstown → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

NYC98LA154

Nobody was injured.

The builder/pilot's carburetor modification that did not allow for rapid fuel demand, which resulted in a loss of engine power of final approach.

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

Read the full NTSB narrative

After 45 minutes of flight, and on final approach, the engine lost power. The helicopter landed hard, the main rotor struck the tail boom, and the helicopter rolled over on its left side. Examination of the helicopter revealed fuel and oil were available, and the throttle linkage was intact. The pilot/owner had recently installed a Power Enhancement Package to the Rotax 582 UL DCDI engine, and adjusted the needle jets to produce suitable EGTs. Based on subsequent research, the pilot stated that engine problems could have occurred going from half, to full throttle rapidly because the main jet was too restrictive to allow enough fuel to pass through quickly. The NTSB database revealed 23 Mini-500 accidents in 1997 and 1998. Within that list, 11 involved a loss of engine power. The Rotax 582 operator's manual stated: ' Danger! This engine, by its design, is subject to sudden stoppage! Engine stoppage can result in crash landings. Such crash landings can lead to serious bodily injury or death. Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other circumstances from which a successful no-power landing cannot be made, after sudden engine stoppage.'

Quoted verbatim from the NTSB record.