Amateur-built SPACE WALKER accident near Cahokia, Illinois, September 9, 2015
On September 9, 2015 at about 7:50 pm local time, a 1998 amateur-built SPACE WALKER, registered N43904, was substantially damaged in an accident during landing near Cahokia, Illinois (St Louis Downtown airport). It was an instructional 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 a proper descent rate during the attempted landing and the flight instructor's delayed attempt to execute a go-around, which resulted in a hard landing, failure of the left main landing gear, and subsequent loss of directional control. Contributing to the accident was an improperly welded landing gear tube.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 9, 2015 · about 7:50 pm local time
- Place
- Cahokia, Illinois · St Louis Downtown · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built SPACE WALKER II, built 1998
- Registration
- N43904 · registry record · serial SW200
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The private pilot and flight instructor were conducting a familiarization flight in the tailwheel-equipped, amateur-built airplane. After completing area maneuvers, the pilot executed two touch-and-go landings. The flight instructor reported that, during the third landing attempt, he noticed that the airplane had developed a high sink rate, so he subsequently took control of the airplane and initiated a go-around as the airplane touched down hard, which damaged the left main landing gear (MLG) and tailwheel attachment spring. The flight instructor was unable to maintain directional control, and the airplane departed the left side of the runway, which further damaged the left MLG. Examination of the left MLG revealed that it failed at the point of a previous weld repair, which was on the lower tube of a multitube group weld and was only partially welded. The improperly welded tube resulted in less-than-intended design strength and contributed to the failure of the left MLG.
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
- Collision during takeoff/land during landing
- Runway excursion during landing (landing roll)
The NTSB's findings
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Instructor/check pilot
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Instructor/check pilot
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Descent/approach/glide path › Not attained/maintained
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Directional control › Not attained/maintained
- cause Personnel issues › Action/decision › Action › Delayed action › Instructor/check pilot
- factor Aircraft › Aircraft systems › Landing gear system › Main landing gear › Incorrect service/maintenance
Flight instructor
- Certificate: flight instructor, commercial pilot, sport pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 6,181 hours in all; 16 in this make and model; 22 in the last 90 days; 10 in the last 30 days; 4,962 as pilot in command; 2,128 on instruments
- Last flight review: December 28, 2013
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: rear
- Injury: no injuries
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 160 hours in all; 1 in this make and model; 3 in the last 90 days; 0 in the last 30 days; 160 as pilot in command; 0 on instruments
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 140 hours
- Last inspection: annual inspection, June 6, 2015
- Maximum gross weight: 1,400 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-235-C2C (piston); 1,473 hours total
The flight
- Departed from: CPS Cahokia IL at 6:30 pm
- Destination: CPS Cahokia IL
- Flight plan: none
- Runway 12R, 7,002 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: scat
- Temperature: 82°F (28°C), dew point 66°F (19°C)
- Altimeter: 29.93 inHg
- Observation at 7:53 pm from KCPS
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on December 28, 2015. 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 Correspondence with Flight Instructor | PDF, 1 page | 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.