Robinson R44 accident near Orlando, Florida, April 20, 2017
On April 20, 2017 at about 2:30 pm local time, a 2006 Robinson R44 (helicopter), registered N899GB, was substantially damaged in an accident during enroute (descent) near Orlando, Florida. It was an other work-use flight under general aviation rules (Part 91). No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A partial failure of the helicopter's engine tachometer due to the separation of one of the magnet assemblies and engine roughness, which precipitated the pilot’s initiation of an off-airport autorotation, during which he applied improper aft cyclic flight control input, which was contrary to the Pilot’s Operating Handbook. The reason for the reported engine roughness could not be determined during postaccident examination and engine test-runs.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 20, 2017 · about 2:30 pm local time
- Place
- Orlando, Florida · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R44 II, built 2006 · all R44s on the register
- Registration
- N899GB · no longer on the register · serial 11190
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot was conducting a local sightseeing flight in a helicopter with two passengers onboard. He reported that, while he was flying southbound and descending from 1,000 to 600 ft, he heard a "pop" sound and noted a corresponding right yaw, followed by vibration and engine roughness. The pilot looked at the instruments, and the main rotor tachometer was indicating that the rpm had dropped to "0" and that the engine tachometer was indicating between 60% and 70%. The pilot immediately initiated an autorotation to a median, and the helicopter landed hard. The helicopter began rolling forward, and in response, the pilot applied aft cyclic control input, which was contrary to the instructions in the Pilot's Operating Handbook, which contained a caution in the emergency procedures section related to power failures that stated to "not apply aft cyclic during touchdown…to prevent possible blade strike to the" tailboom. The pilot's improper control input resulted in the main rotor blades contacting and substantially damaging the tailboom. Postaccident examination of the engine and the tail rotor drive system revealed no evidence of any preimpact mechanical failures or malfunctions that would have precluded normal operation. The engine was test-run, and it started and operated normally. One of the two main rotor tachometer indication system magnet assemblies was separated and not recovered. According to helicopter manufacturer personnel, with only one magnet assembly installed, the main rotor tachometer rpm would indicate about 50% of the actual rotor rpm. Therefore, the main rotor tachometer rpm indication was likely erroneous due to the separation of a magnet assembly from the rotor rpm sensor. The pilot's perception that the main rotor tachometer had decreased to "0" was likely in response to his seeing the needle near the lowest number on the scale. The reason for one of the magnet assemblies' separation could not be determined because it was not located.
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
- Flight instrument malf/fail during enroute (descent)
- Miscellaneous/other during enroute (descent) defining event
- Off-field or emergency landing during emergency descent
- Hard landing during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Aircraft systems › Indicating/recording systems › Indep instrument (clock, etc) › Failure
- factor Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
- factor Personnel issues › Task performance › Use of equip/info › Use of policy/procedure › Pilot of other aircraft
Pilot
- Certificate: commercial pilot
- Ratings: rotorcraft: helicopter
- Flight time: 1,315 hours in all; 1,093 in this make and model; 202 in the last 90 days; 109 in the last 30 days; 1,243 as pilot in command
- Last flight review: March 30, 2016
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 1,142.9 hours
- Last inspection: 100-hour inspection, March 17, 2017; 40 hours since
- Maximum gross weight: 2,500 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 1,143 hours total
- Operator: Air Florida Helicopter Charters, Inc.
The flight
- Departed from: 2DF7 Orlando FL at 2:25 pm
- Destination: 2DF7 Orlando FL
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 100° at 10 knots, gusting 17
- Visibility: 10 statute miles
- Sky: broken clouds at 30,000 ft; scat at 3,700 ft
- Temperature: 81°F (27°C), dew point 61°F (16°C)
- Altimeter: 30.17 inHg
- Observation at 2:53 pm from MCO, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on April 17, 2019. 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 | Pilot Initial Statement | PDF, 1 page | View Download |
| 3 | Record of NTSB Conversations | PDF, 3 pages | View Download |
| 4 | Excerpts from Pilot's Operating Handbook | PDF, 2 pages | View Download |
| 5 | Excerpts from Illustrated Parts Catalog | PDF, 2 pages | View Download |
| 6 | Engine Examination and Test Run Results | PDF, 4 pages | View Download |
| 7 | Investigative Photographs | PDF, 6 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.