Piper PA-25-235 and Cirrus Design CORP SR20 and Schweizer SGS 2-32 mid-air collision near Boulder, Colorado, February 6, 2010
On February 6, 2010 at about 8:27 pm local time, 3 aircraft, Piper PA-25-235 (N8718L) and Cirrus Design CORP SR20 (N825BC) and Schweizer SGS 2-32 (N2472W), were involved in a mid-air collision near Boulder, Colorado. 3 people were killed; 3 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of both pilots to see and avoid the other resulting in a midair collision. Contributing to the accident was the lack of perceived visual relative motion of the Piper and the Cirrus to the pilot of each airplane, the terrain background, and the overcast weather conditions making it difficult for either pilot to visually acquire the other aircraft.
The failure of both pilots to see and avoid the other resulting in a midair collision. Contributing to the accident was the lack of perceived visual relative motion of the Piper and the Cirrus to the pilot of each airplane, the terrain background, and the overcast weather conditions making it difficult for either pilot to visually acquire the other aircraft.
The failure of both pilots to see and avoid the other resulting in a midair collision. Contributing to the accident was the lack of perceived visual relative motion of the Piper and the Cirrus to the pilot of each airplane, the terrain background, and the overcast weather conditions making it difficult for either pilot to visually acquire the other aircraft.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 6, 2010 · about 8:27 pm local time
- Place
- Boulder, Colorado · map
- Type
- Accident · mid-air collision
- Injuries
- 3 people were killed; 3 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft 1
- Piper PA-25-235 · all PA-25-235s on the register
- Registration
- N8718L · no longer on the register · serial 17256378
- Damage
- Substantial damage
- Flight
- Glider-towing flight · general aviation rules (Part 91)
- Aircraft 2
- Cirrus Design CORP SR20
- Registration
- N825BC · no longer on the register · serial 1655
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
- Aircraft 3
- Schweizer SGS 2-32 · all SGS 2-32s on the register
- Registration
- N2472W · registry record · serial 47
- Damage
- Not recorded
- Flight
- Glider-towing flight · general aviation rules (Part 91)
The NTSB's narrative for the Piper PA-25-235 final · quoted from the NTSB record
While conducting glider-tow operations, the right wing of a Piper PA-25 was struck at a 90 degree angle by a Cirrus SR20. Analysis of the radar information, the flight condition of both airplanes, and the pilots' visibility in their respective cockpit configurations, suggests that until just prior to the impact, the Piper would have been located below the horizon and against the background of the surrounding terrain and city, between the 10 and 11 o’clock position of the Cirrus pilot. The Piper remained in this same relative position in the windscreen of the Cirrus pilot for the entire duration of its 7 minute flight. The Cirrus would have been above the horizon, against the white overcast sky, in about the 1 to 2 o’clock position of the Piper pilot. The Cirrus would have only appeared in this position after the Piper pilot completed the last turn and was headed to the west, which would have been (at most) the last 3 minutes of the flight. Visual meteorological conditions existed at the time of the accident with an overcast layer and visibility of 8 miles. The overcast sky conditions likely made it difficult for the Piper pilot to detect the primarily white-colored Cirrus. The lack of maneuvering, as observed by the glider pilot prior to the accident, suggests that neither the pilot of the Cirrus nor the pilot of the Piper observed the other airplane prior to the accident. If the Piper pilot had observed the Cirrus prior to the impact, his ability to maneuver to avoid an impact would have been severely limited due to the glider in tow. A postaccident examination of the engine and flight control systems on both airplanes revealed no mechanical anomalies that would have prevented either pilot from maneuvering to avoid an impact. Medical and pathological examination of both pilots revealed no medical or toxicological issues that would have precluded either pilot from operating their airplane in a safe manner prior to the accident.
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 NTSB's narrative for the Cirrus Design CORP SR20 final · quoted from the NTSB record
While conducting glider-tow operations, the right wing of a Piper PA-25 was struck at a 90 degree angle by a Cirrus SR20. Analysis of the radar information, the flight condition of both airplanes, and the pilots' visibility in their respective cockpit configurations, suggests that until just prior to the impact, the Piper would have been located below the horizon and against the background of the surrounding terrain and city, between the 10 and 11 o’clock position of the Cirrus pilot. The Piper remained in this same relative position in the windscreen of the Cirrus pilot for the entire duration of its 7 minute flight. The Cirrus would have been above the horizon, against the white overcast sky, in about the 1 to 2 o’clock position of the Piper pilot. The Cirrus would have only appeared in this position after the Piper pilot completed the last turn and was headed to the west, which would have been (at most) the last 3 minutes of the flight. Visual meteorological conditions existed at the time of the accident with an overcast layer and visibility of 8 miles. The overcast sky conditions likely made it difficult for the Piper pilot to detect the primarily white-colored Cirrus. The lack of maneuvering, as observed by the glider pilot prior to the accident, suggests that neither the pilot of the Cirrus nor the pilot of the Piper observed the other airplane prior to the accident. If the Piper pilot had observed the Cirrus prior to the impact, his ability to maneuver to avoid an impact would have been severely limited due to the glider in tow. A postaccident examination of the engine and flight control systems on both airplanes revealed no mechanical anomalies that would have prevented either pilot from maneuvering to avoid an impact. Medical and pathological examination of both pilots revealed no medical or toxicological issues that would have precluded either pilot from operating their airplane in a safe manner prior to the accident.
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 NTSB's narrative for the Schweizer SGS 2-32 final · quoted from the NTSB record
While conducting glider-tow operations, the right wing of a Piper PA-25 was struck at a 90 degree angle by a Cirrus SR20. Analysis of the radar information, the flight condition of both airplanes, and the pilots' visibility in their respective cockpit configurations, suggests that until just prior to the impact, the Piper would have been located below the horizon and against the background of the surrounding terrain and city, between the 10 and 11 o’clock position of the Cirrus pilot. The Piper remained in this same relative position in the windscreen of the Cirrus pilot for the entire duration of its 7 minute flight. The Cirrus would have been above the horizon, against the white overcast sky, in about the 1 to 2 o’clock position of the Piper pilot. The Cirrus would have only appeared in this position after the Piper pilot completed the last turn and was headed to the west, which would have been (at most) the last 3 minutes of the flight. Visual meteorological conditions existed at the time of the accident with an overcast layer and visibility of 8 miles. The overcast sky conditions likely made it difficult for the Piper pilot to detect the primarily white-colored Cirrus. The lack of maneuvering, as observed by the glider pilot prior to the accident, suggests that neither the pilot of the Cirrus nor the pilot of the Piper observed the other airplane prior to the accident. If the Piper pilot had observed the Cirrus prior to the impact, his ability to maneuver to avoid an impact would have been severely limited due to the glider in tow. A postaccident examination of the engine and flight control systems on both airplanes revealed no mechanical anomalies that would have prevented either pilot from maneuvering to avoid an impact. Medical and pathological examination of both pilots revealed no medical or toxicological issues that would have precluded either pilot from operating their airplane in a safe manner prior to the accident.
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 for the Piper PA-25-235 from the NTSB's investigation tables, in plain English
What happened, in order
- Glider tow event during enroute
- Midair collision during enroute defining event
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot
- factor Environmental issues › Operating environment › (general) › (general) › Contributed to outcome
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 1,112 hours in all; 260 in this make and model; 86 in the last 90 days; 14 in the last 30 days; 1,005 as pilot in command; 20 on instruments
- Last flight review: October 24, 2009
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: frt
- Injury: fatal
The aircraft
- Airframe total time: 9,929 hours
- Last inspection: continuous airworthiness programme, February 1, 2010
- Seats: 1
- Landing gear: fixed
- Operator: Mile High Gliding Inc
The flight
- Departed from: KBDU Boulder CO at 8:20 pm
- Destination: KBDU Boulder CO
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 8 statute miles
- Sky: overcast at 12,000 ft; scat at 8,000 ft
- Temperature: 39°F (4°C), dew point 21°F (-6°C)
- Altimeter: 29.88 inHg
- Observation at 7:47 pm from KBJC
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
The factual record for the Cirrus Design CORP SR20 from the NTSB's investigation tables, in plain English
What happened, in order
- Midair collision during enroute
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot
- factor Environmental issues › Operating environment › (general) › (general) › Contributed to outcome
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 640 hours in all; 359 in this make and model; 8 in the last 90 days; 4 in the last 30 days
- Last flight review: May 15, 2009
- Medical certificate: Class 3
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 319 hours
- Last inspection: annual inspection, April 8, 2009
- Seats: 4
- Landing gear: fixed
- Engine: Cont Motor IO-360-ES (piston); 0 hours total
- Fire in flight and on the ground
The flight
- Departed from: KEIK Erie CO at 8:00 pm
- Destination: KEIK Erie CO
- Flight plan: none
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
The factual record for the Schweizer SGS 2-32 from the NTSB's investigation tables, in plain English
What happened, in order
- Glider tow event during enroute
The NTSB's findings
- cause Personnel issues › Psychological › Attention/monitoring › Monitoring other aircraft › Pilot
- factor Environmental issues › Operating environment › (general) › (general) › Contributed to outcome
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane; rotorcraft: glider
- Flight time: 2,044 hours in all; 3 in this make and model; 66 in the last 90 days; 13 in the last 30 days; 1,972 as pilot in command; 1,577 on instruments
- Last flight review: June 7, 2009
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 6,107 hours
- Last inspection: annual inspection, August 24, 2009
- Maximum gross weight: 1,340 lb
- Seats: 3
- Landing gear: fixed
- Operator: Mile High Gliding INC
The flight
- Departed from: KBDU Boulder CO at 8:20 pm
- Destination: KBDU Boulder CO
- Flight plan: none
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 2 |
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.
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.