Amateur-built MAC CUB accident near Ogden, Utah, March 5, 2018
On March 5, 2018 at about 9:30 pm local time, a 2005 amateur-built MAC CUB, registered N669WH, was substantially damaged in an accident during enroute (cruise) near Ogden, Utah (Skypark 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 use carburetor heat during the flight, which resulted in a partial loss of engine power due to carburetor icing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 5, 2018 · about 9:30 pm local time
- Place
- Ogden, Utah · Skypark · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built MAC CUB NO SERIES, built 2005
- Registration
- N669WH · registry record · serial 001
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot and pilot rated passenger were conducting a local flight when the engine began to run roughly, and partial loss of engine power followed. The airplane was unable to maintain altitude, and the pilot made a forced landing onto a muddy road. During the landing roll, the airplane sunk in the mud, nosed over, and came to rest inverted, causing substantial damage to the left wing and vertical stabilizer. An engine examination and test run were performed, which revealed no preaccident mechanical failures or malfunctions that would have precluded normal operation. The nearest weather reporting facility, located about 6 nautical miles from the accident site, reported a temperature of 35.6oF and a dew point of 19.4oF, which was in the range of atmosphere conditions that are conducive to carburetor icing at glide and cruise power settings. The pilot reported that the carburetor heat was not activated at the time of the partial loss of engine power. The pilot also reported that he was in the rear airplane seat. Although the pilot had access to both sets of flight controls, the rear seat compartment was not equipped with a carburetor heat control handle. Engine power would likely have been restored if the carburetor heat had been engaged.
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 (cruise) defining event
- Nose over/nose down during landing (landing roll)
The NTSB's findings
- Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
- Environmental issues › Conditions/weather/phenomena › Temp/humidity/pressure › Conducive to carburetor icing › Effect on equipment
- Aircraft › Aircraft power plant › Engine fuel and control › Fuel control/carburetor › Incorrect use/operation
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 3,200 hours in all; 16 in this make and model; 30 in the last 90 days; 12 in the last 30 days; 2,611 as pilot in command; 760 on instruments
- Last flight review: April 15, 2016
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: rear
- Injury: no injuries
Pilot-Rated Passenger
- Certificate: private
- Ratings: single-engine land
- Medical certificate: Class 3
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 290 hours
- Last inspection: condition inspection, October 6, 2017; 100 hours since
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-360-A4G (piston); 199 hours total
The flight
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 300° at 8 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 4,100 ft; clear
- Temperature: 36°F (2°C), dew point 19°F (-7°C)
- Altimeter: 30.30 inHg
- Observation at 1:53 pm from OGD, 6 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on February 24, 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 | Record of Conversation (Lee) | PDF, 1 page | View Download |
| 3 | NTSB Examination Report | PDF, 6 pages | View Download |
| 4 | Report from FAA | PDF, 1 page | View Download |
| 5 | FAA Saib CE-09-35 Carburetor Icing Prevention | PDF, 3 pages | View Download |
| 6 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 7 | Photos - Pilot | PDF, 2 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.