Enstrom F-28C accident near Anchorage, Alaska, March 5, 2023
On March 5, 2023 at about 11:00 pm local time, a 2015 Enstrom F-28C (helicopter), registered N5688R, was substantially damaged in an accident during landing near Anchorage, Alaska (Lake Hood Seaplane airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s failure to maintain main rotor rpm on takeoff, which resulted in a forced run-on landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 5, 2023 · about 11:00 pm local time
- Place
- Anchorage, Alaska · Lake Hood Seaplane · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Enstrom F-28C, built 2015 · all F-28Cs on the register
- Registration
- N5688R · registry record · serial 466-2
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that the helicopter preflight and engine runup were normal; however, he could not maintain main rotor rpm on departure and the engine lost partial power. The pilot made a run-on landing to a snow-covered lake, which resulted in substantial damage to the tail boom. Postaccident examination of the engine revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. Since there were no mechanical anomalies with the helicopter, it is likely the pilot allowed the main rotor rpm to decrease and exceeded the available engine power to recover from the low main rotor rpm condition. When the main rotor rpm decreases, the amount of power the engine can produce also decreases, which is likely the reason the pilot perceived a partial loss of engine power. In addition, the obstacles along the departure path prevented the pilot from lowering the collective to regain main rotor rpm, which resulted in the pilot electing to perform a run-on landing.
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
- Hard landing during landing defining event
- Miscellaneous/other during takeoff
The NTSB's findings
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Powerplant parameters › Capability exceeded
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Prop/rotor parameters › Not attained/maintained
- Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; multi-engine sea; single-engine land; single-engine sea; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; rotorcraft: helicopter
- Flight time: 21,000 hours in all; 900 in this make and model; 13 in the last 90 days; 11 in the last 30 days; 20,500 as pilot in command; 100 on instruments
- Last flight review: January 15, 2022
- Medical certificate: Class 2
- Seat: left
- Injury: no injuries
Passenger
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 1,833.9 hours
- Last inspection: annual inspection, May 1, 2022; 3.2 hours since
- Maximum gross weight: 2,350 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming HIO-36-E1AD (piston); 0 hours total
The flight
- Destination: UUO Willow AK
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 080° at 4 knots
- Visibility: 10 statute miles
- Sky: scat at 20,000 ft
- Temperature: 19°F (-7°C), dew point 1°F (-17°C)
- Altimeter: 30.40 inHg
- Observation at 1:53 pm from PANC, 2 miles away
Weather report (METAR): PANC 052253Z 08004KT 10SM SCT200 M07/M17 A3040 RMK AO2 SLP297 T10671167
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
4 documents, released by the NTSB on May 16, 2024. 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 | Engine Examination | PDF, 12 pages | View Download |
| 3 | Maintenance Records | PDF, 6 pages | View Download |
| 4 | Investigative Photographs | PDF, 4 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number ANC23LA024.