Pipistrel Alpha Trainer accident near Fort Collins, Colorado, May 28, 2021
On May 28, 2021 at about 4:30 pm local time, a 2012 Pipistrel Alpha Trainer, registered N119JP, was substantially damaged in an accident during enroute near Fort Collins, Colorado. It was an instructional 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
A partial loss of engine power due to the failure of the throttle control cable, which resulted in the loss of control of the dual carburetor system. The cable failure was a result of improper soldering at the throttle cable input terminal on the splitter assembly, which led to the progressive separation of the cable strands.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 28, 2021 · about 4:30 pm local time
- Place
- Fort Collins, Colorado · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Pipistrel Alpha Trainer, built 2012 · all Alpha Trainers on the register
- Registration
- N119JP · no longer on the register · serial 478 AT 912 LSA
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight instructor reported that he and the pilot took off in the airplane to conduct a flight review and proceeded to the practice area. They conducted flight review maneuvers, emergency procedures, and the flight instructor demonstrated a power-on stall. The pilot took over the controls and when he added power, the engine did not respond. He manipulated the throttle several times, but the engine had reduced to idle power and would not change. The flight instructor initiated an emergency landing. The airplane descended to a nearby field and touched down. The nosewheel sank into a small ridge and the airplane flipped upside down and slid to a stop. A postaccident examination of the throttle/choke splitter assembly revealed the single throttle cable, which runs to the cockpit, separated from the throttle/choke cable splitter assembly. A metallurgical examination revealed a lack of solder material where the input throttle cable connects to the terminal end of the splitter assembly. The lack of solder material left a void in the cable connection with the terminal fitting, which allowed the individual cable strands to fail in a progressive manner, until the cable eventually separated from the terminal fitting. A lack of solder was also noted at the output end of the throttle cable connection with the splitter assembly. The choke cable connections were normal. The airplane maintenance manual indicates that the throttle and control cables need to be replaced every 5 years. In addition, the manual cautions that “all of the time limits…. must be considered when performing the 100 hour/annual inspection. Removal or overhaul of any these items must be entered into the aircraft technical logbook.” There is no logbook entry that explicitly states that the throttle and choke cables were replaced. Therefore, it could not be determined who produced the deficient solder joints or how long they had been in service.
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
- Loss of engine power (partial) during enroute defining event
- Nose over/nose down during landing (flare/touchdown)
The NTSB's findings
- Aircraft › Aircraft power plant › Engine controls › Power lever › Failure
- Personnel issues › Task performance › Maintenance › Fabrication › Unknown/Not determined
- Environmental issues › Physical environment › Terrain › Rough terrain › Contributed to outcome
Pilot
- Certificate: sport pilot
- Medical certificate: BasicMed (without waivers/limitations)
- Seat: left
- Injury: minor injuries
Flight instructor
- Certificate: flight instructor, private, sport pilot
- Ratings: single-engine land; instructor: airplane single-engine
- Flight time: 1,102 hours in all; 33 in this make and model; 88 in the last 90 days; 31 in the last 30 days; 904 as pilot in command; 155 on instruments
- Medical certificate: Sport Pilot
- Seat: rgt
- Injury: serious injuries
The aircraft
- Airframe total time: 616 hours
- Last inspection: annual inspection, May 25, 2021; 22.4 hours since
- Maximum gross weight: 1,212 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 912 UL2 (piston); 0 hours total
The flight
- Departed from: FNL Loveland CO at 9:41 am
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 63°F (17°C), dew point 48°F (9°C)
- Altimeter: 30.09 inHg
- Observation at 10:56 am from KFNL
Weather report (METAR): KFNL 281656Z VRB04KT 10SM CLR 17/09 A3009 RMK AO2 SLP150 T01670089 PNO $=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on December 7, 2022. 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 | FAA Roc | PDF, 3 pages | View Download |
| 3 | Pipistrel Maintenance Manual Excerpts | PDF, 5 pages | View Download |
| 4 | Materials Laboratory Factual Report 22-004 | PDF, 16 pages | View Download |
| 5 | Airframe Maintenance Records Excerpts | PDF, 15 pages | View Download |
| 6 | Engine Maintenance Records Excerpts | PDF, 5 pages | View Download |
| 7 | Service Bulletin - Throttle and Choke Cable Replacement | PDF, 6 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.