Robinson R 22 Mariner accident near Lantana, Florida, July 28, 2004
On July 28, 2004 at about 8:10 pm local time, a Robinson R 22 Mariner (helicopter), registered N516PB, was substantially damaged in an accident near Lantana, Florida (Palm Beach County Park airport). It was an instructional flight under general aviation rules (Part 91). 1 person had minor injuries; 1 other was unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of the pilot-in-command to maintain recommended main rotor RPM following a reported total loss of engine power due to undetermined reasons, during a practice autorotation resulting in a hard landing and subsequent roll over.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 28, 2004 · about 8:10 pm local time
- Place
- Lantana, Florida · Palm Beach County Park · map
- Type
- Accident
- Injuries
- 1 person had minor injuries; 1 other was unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R 22 Mariner · all R 22 Mariners on the register
- Registration
- N516PB · no longer on the register · serial 2315M
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter landed hard and rolled over after the certified flight instructor (CFI) attempted to recover from a simulated autorotative descent. According to the CFI, as he attempted to level off at 75 to 100 feet above the ground, the helicopter yawed sharply to the left along with a loss of main rotor rpm, and despite his efforts to recover, the helicopter touched down left skid low. The engine was later placed in a test cell and when started operated to approximately 2,550 rpm instead of 2,700 rpm. The No. 3 cylinder was noted to only have 5 psi during the differential compression test. Further examination of the No. 3 cylinder by the cylinder manufacturer revealed discolorations which are typical of high temperature operations; wear on the exhaust valve seating face and exhaust valve guide was noted.
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
Flight instructor
- Certificate: airline transport pilot
- Ratings: instructor: helicopter; instructor: instrument helicopter; instrument: helicopter; rotorcraft: helicopter
- Flight time: 7,000 hours in all; 1,500 in this make and model; 100 in the last 90 days; 25 in the last 30 days; 7,000 as pilot in command; 2,000 on instruments
- Last flight review: July 27, 2004
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: rgt
- Injury: no injuries
Dual student
- Certificate: commercial pilot
- Ratings: instrument: helicopter; rotorcraft: helicopter
- Flight time: 185 hours in all; 184 in this make and model; 35 in the last 90 days; 11 in the last 30 days; 135 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
- Injury: minor injuries
The aircraft
- Airframe total time: 2,382.6 hours
- Last inspection: 100-hour inspection, July 2, 2004; 86 hours since
- Maximum gross weight: 1,370 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-B2C (piston); 0 hours total
The flight
- Departed from: KLNA Lantana FL at 7:34 pm
- Destination: KLNA Lantana FL
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 230° at 4 knots
- Visibility: 5 statute miles
- Sky: broken clouds at 5,000 ft; scat at 2,000 ft
- Temperature: 77°F (25°C), dew point 75°F (24°C)
- Altimeter: 29.95 inHg
- Observation at 8:16 pm from KPBI
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 |
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.