ASN Wikibase Occurrence # 30378
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Thursday 7 October 1999 |
| Time: | 20:05 LT |
| Type: |  McDonnell Douglas MD 500E (369E) |
| Owner/operator: | Riverside Co Sheriff's Department |
| Registration: | N991SD |
| MSN: | 0500E |
| Year of manufacture: | 1992 |
| Total airframe hrs: | 5474 hours |
| Engine model: | Allison 250C20B |
| Fatalities: | Fatalities: 0 / Occupants: 3 |
| Aircraft damage: | Substantial |
| Category: | Accident |
| Location: | Moreno Valley, CA -
 United States of America
|
| Phase: | En route |
| Nature: | Aerial patrol |
| Departure airport: | Hemet, CA |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
A McDonnell Douglas 369E helicopter, N991SD, was substantially damaged during a forced landing at Moreno Valley, California, following an in-flight loss of directional control. The commercial pilot and two observer
crewmembers were not injured. The helicopter was operated by the Riverside County Sheriff's Department under the provisions of 14 CFR Part 91 as a public-use aircraft. Visual meteorological conditions prevailed and no flight plan was filed for the local area patrol flight, which originated from Hemet, California, at 1950.
According to the Sheriff's Department report, it was a dark night and the winds aloft were northerly at 20 to 25 knots, at 500 feet agl, as the pilot orbited over ground based law enforcement activity. In accordance with department operating procedures, the pilot had identified a school athletic field as a suitable emergency landing site. He was attempting to shine the helicopter's spotlight on a vehicle; however, the northerly wind kept blowing the aircraft well south of the location on each of the first two orbits. On the third orbit, he
inadvertently allowed the helicopter to slow below translational lift speed and the helicopter yawed 180 degrees to the right uncontrollably. The pilot momentarily recovered directional control of the helicopter but then the right yaw resumed. He made several more attempts to recover directional control of the helicopter but when he saw the altitude becoming low, he flew to the pre-selected landing zone where the helicopter landed hard while in a right yawing spin. During the landing the main rotor blades severed the tail boom and the helicopter came to rest on its right side.
Probable Cause and Findings
The failure of the pilot to maintain sufficient forward airspeed to preclude an inadvertent encounter with loss of tail rotor effectiveness, which resulted in a loss of yaw control. The pilot's failure to initiate timely remedial action is a factor.
Accident investigation:
 |
|
Sources:
NTSB
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 27-Sep-2008 01:00 | ASN archive | Added |
| 11-Oct-2021 19:05 | harro | Updated [Date, Time, Operator, Total fatalities, Total occupants, Other fatalities, Location, Country, Phase, Nature, Departure airport, Source, Damage, Narrative, Accident report] |
| 30-May-2023 01:52 | Ron Averes | Updated [[Date, Time, Operator, Total fatalities, Total occupants, Other fatalities, Location, Country, Phase, Nature, Departure airport, Source, Damage, Narrative, Accident report]] |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation