Mdhi 369E accident near Pahoa, Hawaii, January 22, 2005
On January 22, 2005 at about 1:30 am local time, a Mdhi 369E (helicopter), registered N142MK, was substantially damaged in an accident near Pahoa, Hawaii. It was flown under charter and air-taxi rules (Part 135). No one was hurt; 5 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the in-flight separation of the tail rotor blade abrasion strip due to a degraded adhesive bond and fatigue fracture of the metallic abrasion strip. The ultimate cause for the degraded bond is unknown.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 22, 2005 · about 1:30 am local time
- Place
- Pahoa, Hawaii · map
- Type
- Accident
- Injuries
- No one was hurt; 5 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mdhi 369E
- Registration
- N142MK · no longer on the register · serial 187E
- Damage
- Substantial damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The helicopter impacted small trees during an autorotational landing that was preceded by the in-flight separation of a tail rotor blade abrasion strip. According to the pilot, the helicopter developed a "sudden vibration in the tail rotor pedals followed immediately by a loud 'crack' or 'snap', and then an extremely loud banging noise and a sharp vibration in both airframe as well as the tail rotor pedals." The pilot made an off-airport autorotational landing to a clearing, but during the landing flare, the tail section snagged a tree. Post-accident examination of the tail rotor blades revealed that the leading edge abrasion strip debonded from one of the blades. Based on the surface finish, the debonding was most probably an adhesive failure at the interface with the abrasion strip. The cause of the bond failure is unknown, but could be the result of in-service conditions, a production problem, or undetected impact damage. The adhesive is the primary means of holding the strip to the blade, but there are also two rivets on the inboard end of the blade that serve as a secondary securing method. The abrasion strip fractured at the outboard rivet and the fracture surface revealed evidence of fatigue cracking indicating that the abrasion strip was completely debonded for a period of time. In addition, dark sooty deposits were visible in the bond area on both sides of the blade. Maintenance records indicated that the helicopter underwent a 100-hour inspection approximately 62 hours prior to the accident. The inspection calls for a visual examination of the tail rotor blades to ensure no separation of the bond around the edges or at the tip end of the blade exist. The inspection process calls for a dye-penetrant inspection or tap test only if a debond is suspected. However, detection of the debond during the visual only 100-hour inspection would depend on whether the separation intersected on the strip edges. The preflight examination procedures called for the pilot to visually examine the tail rotor blades to ensure there is no debonding along the abrasion strip-to-airfoil bond line. The pilot reported that he inspected the abrasion strip prior to the accident flight, but did not notice any evidence of an abrasion strip debond. The blade accumulated 2,379.7 total hours of operation, and 1,820.6 hours since its last overhaul.
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
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane; rotorcraft: helicopter
- Flight time: 8,795 hours in all; 3,650 in this make and model
- Last flight review: August 1, 2004
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 7,592.6 hours
- Last inspection: 100-hour inspection, January 1, 2005; 65.2 hours since
- Maximum gross weight: 3,000 lb
- Seats: 5
- Landing gear: fixed
- Engine: Rolls-Royce 250-C20B (turboshaft); 0 hours total
- Operator: K & S Helicopters, Inc.
The flight
- Departed from: ITO Hilo HI at 1:00 am
Weather at the time
- Light: daylight
- Wind: from 250° at 7 knots
- Visibility: 10 statute miles
- Sky: overcast at 4,500 ft; scat at 3,600 ft
- Temperature: 81°F (27°C), dew point 70°F (21°C)
- Altimeter: 29.84 inHg
- Observation at 10:53 pm from KOA, 45 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 4 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N142MK 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.