Mcdonnell Douglas 600N accident near San Diego, California, February 21, 2001
On February 21, 2001 at about 7:13 pm local time, a Mcdonnell Douglas 600N (helicopter), registered N606BP, was substantially damaged in an accident near San Diego, California (Brown Field Muni). 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 student pilot's improper use of the rotorcraft flight controls, and the instructor pilot's inadequate supervision of the maneuver.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 21, 2001 · about 7:13 pm local time
- Place
- San Diego, California · Brown Field Muni · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas 600N
- Registration
- N606BP · no longer on the register · serial RN-035
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During the landing slide, the main rotor blew back, contacted the tail boom, and severed it. The flight purpose was refresher training and the specific maneuver at the time of the accident was training in the procedure for a stuck (fixed) right pedal. According to the flight crew, there were no mechanical discrepancies with the helicopter. A run-on landing with the fixed right pedal was made to the 260-degree taxiway. The wind reported at the airport about 14 minutes after the accident was 330 degrees at 6 knots. The pilots reported that the wind was 310 degrees at 6 to 8 knots with gusts to 12 knots. According to information provided by the flight crew, the training pilot accomplished the maneuver: aligned with the runway heading with an airspeed between 55-65 knots; the instructor pilot (IP) held right pedal to induce a 10-degree right yaw; touchdown was estimated to occur about 30-40 knots; the low rotor rpm horn was "on" at or near touchdown, but the rotor speed was not noted; the collective was positioned at some point above half travel; cyclic was slightly forward of neutral; shortly after touchdown both pilots felt the main rotor strike the tail boom; directional control was lost and the helicopter rotated about 220 degrees nose right before coming to rest, upright. The manufacturer indicated that main rotor/tail boom contact from blowback of the main rotor may result from forward velocity and low/decaying main rotor rpm (advance ratio) due to a high collective position during the ground run-out phase following the 30-knot plus touchdown. The blowback condition is exacerbated by the high angle pitch setting which causes blade stall over a large portion of the rotor disk. A blowback condition is present in all helicopters. It may be more pronounced in the MD600N (versus the 500N) due to greater helicopter gross weight, reduced flare/deceleration capabilities because of tail boom length and installation angle, and the increased surface of the additional main rotor blade resulting in a more rapid decay of main rotor rpm. A caution in the helicopter's Rotorcraft Flight Manual specifies for practice autorotation landings to avoid conditions of ROTOR RPM (Nr) less than 60 percent with headwinds across the rotor greater than 30 knots during touchdown autorotations. These conditions during touchdown and subsequent ground slide, can lead to excessive rotor blowback, reduction in blade tip to tail boom clearance, and subsequent damage to the aircraft. Avoid these conditions by reducing collective pitch after touchdown (surface conditions permitting) and minimizing ground run.
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
Pilot
- Certificate: airline transport pilot, flight engineer
- Ratings: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Flight time: 4,740 hours in all; 277 in this make and model; 100 in the last 90 days; 50 in the last 30 days; 3,000 as pilot in command
- Last flight review: December 6, 2000
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
- Injury: no injuries
Pilot (unmanned)
- Certificate: airline transport pilot, flight instructor
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instructor: instrument airplane; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 12,120 hours in all; 608 in this make and model; 94 in the last 90 days; 28 in the last 30 days; 12,050 as pilot in command; 3,500 on instruments
- Last flight review: September 20, 2000
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 795.4 hours
- Last inspection: 100-hour inspection, January 16, 2001; 95.4 hours since
- Maximum gross weight: 4,100 lb
- Seats: 6
- Landing gear: fixed
- Engine: Allison 250-C47M (turboshaft); 0 hours total
The flight
- Departed from: SDM San Diego CA at 6:30 pm
- Destination: SDM San Diego CA
- Runway 26L, 3,057 ft by 50 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 330° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 63°F (17°C), dew point 45°F (7°C)
- Altimeter: 30.22 inHg
- Observation at 7:27 pm from SDM
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
Other NTSB records under N606BP the same tail number, which may have belonged to a different aircraft at the time
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.