Robinson Helicopter R44 accident near Chatham, New Jersey, February 24, 2017
On February 24, 2017 at about 11:23 pm local time, a 1999 Robinson Helicopter R44, registered N44EK, was substantially damaged in an accident during enroute near Chatham, New Jersey. It was a personal flight under general aviation rules (Part 91). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Maintenance personnel's improper installation and inspection of the crankshaft gear bolt during major overhaul, which resulted in the crankshaft gear disengaging from the accessory gears of the engine and a subsequent loss of power.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 24, 2017 · about 11:23 pm local time
- Place
- Chatham, New Jersey · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter R44 UNDESIGNAT, built 1999 · all R44s on the register
- Registration
- N44EK · registry record · serial 0690
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The private pilot was on the second leg of a cross-country flight in the helicopter. After about 45 minutes and while in cruise flight at 1,800 ft mean sea level, the engine lost total power; the low rpm warning sounded, and the pilot initiated an autorotation in the congested area during nighttime conditions. During the autorotation, the helicopter struck a building, which resulted in substantial damage to the fuselage. Postaccident examination of the engine revealed that the crankshaft gear bolt was about 3/16 inch from the seated position. The safety lockplate washer was worn, the back of the bolt head displayed rotational scoring, the bottom threads of the bolt were damaged, and the alignment dowel had sheared. The engine had accumulated 5.9 hours total time since undergoing major overhaul about 1 year before the accident. It is likely that, when the engine was overhauled, the crankshaft gear bolt was not properly seated against the gear, which resulted in the crankshaft gear disengaging from the accessory gears and a subsequent total loss of engine power.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Aircraft maintenance event during prior to flight
- Loss of engine power (total) during enroute defining event
- Autorotation Collision with terrain or object (not controlled flight into terrain)
The NTSB's findings
- cause Personnel issues › Task performance › Maintenance › Scheduled/routine maintenance › Maintenance personnel
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng rear section › Incorrect service/maintenance
- Environmental issues › Physical environment › Object/animal/substance › Residence/building › Contributed to outcome
Pilot
- Certificate: private
- Ratings: rotorcraft: helicopter
- Flight time: 1,600 hours in all; 1,100 in this make and model; 20 in the last 90 days; 10 in the last 30 days
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 2,006 hours
- Last inspection: annual inspection, March 7, 2016; 6 hours since
- Maximum gross weight: 2,400 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-540 SERIES (piston); 6 hours total
The flight
- Departed from: MIV Millville NJ at 10:45 pm
- Destination: N07 Lincoln Park NJ
- Flight plan: none
Weather at the time
- Light: night
- Wind: from 180° at 7 knots
- Visibility: 15 statute miles
- Sky: a few clouds at 6,000 ft
- Temperature: 68°F (20°C), dew point 54°F (12°C)
- Altimeter: 29.84 inHg
- Observation at 6:45 pm from MMU, 4 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
11 documents, released by the NTSB on December 13, 2019. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Maintenance Records Excerpt | PDF, 5 pages | View Download |
| 3 | Fuel Receipt | PDF, 1 page | View Download |
| 4 | FAA Inspectors On-scene Report | PDF, 2 pages | View Download |
| 5 | FAA Inspectors Statement | PDF, 1 page | View Download |
| 6 | Mmu Atct Transcript of Radio Communications_excerpt | PDF, 2 pages | View Download |
| 7 | Witness Statement_faa | PDF, 1 page | View Download |
| 8 | Record of Weather | PDF, 1 page | View Download |
| 9 | NTSB Engine Examination | PDF, 9 pages | View Download |
| 10 | Photograph of Crankshaft Gear Bolt During Examination | PDF, 1 page | View Download |
| 11 | Photo Array- Accident Site and Damage | PDF, 3 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Other NTSB records under N44EK the same tail number, which may have belonged to a different aircraft at the time
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.