# NTSB LAX98LA076: McDonnell Douglas 600N, N176SP, Mesa, AZ, January 17, 1998 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 16, 1998, 17:30 local (Jan 17, 1998, 00:30 UTC) - Place: Mesa, AZ - Coordinates: 33.510608, -111.580551 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.5106&lon=-111.5806&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report February 15, 2001 - Report: Approved by Office Director - NTSB case key (mKey): 30023 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX98LA076 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30023/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=30023 - Page: https://openairdocs.org/ntsb/LAX98LA076 ## Probable cause The second pilot misjudging his flare and the delayed remedial actions by the pilot-in-command. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Hard landing, landing - flare/touchdown - misc rotorcraft,main rotor/tail boom contact - terrain condition - grass - flare - misjudged, pilot in command (cause) - remedial action - delayed, pilot in command(cfi) (cause) ## Analysis The CFI was having the second pilot execute straight in autorotations for familiarization training. The second pilot initiated the autorotation with the rotor in the low range and the CFI instructed the second pilot to reduce collective, which increased their rate of descent. The CFI said that about 18 feet, the second pilot applied 60 percent collective, leveled somewhat, and the nose yawed to the left. The CFI applied full right pedal in an attempt to correct the yaw, but the nose remained yawed to the left approximately 15 degrees. The aircraft hit the ground with the left heel first followed by the nose pitching forward. The CFI stated he applied slight aft cyclic and felt the main rotor contact the tail boom. ## Factual narrative On January 16, 1998, at 1730 hours mountain standard time, a McDonnell Douglas 600N, N176SP, sustained substantial damage during the touchdown autorotation at Mesa, Arizona. The aircraft was owned and operated by the West Virginia State Police, and one of their pilots was undergoing familiarization training by a Boeing/McDonnell Douglas instructor pilot. The flight instructor and commercial pilot who was receiving instruction were not injured. The flight originated at Falcon Field at 1600. The aircraft was being operated on a standard airworthiness certificate which was issued on January 14, 1998. The West Virginia State Police pilot (referred to as the second pilot) was undergoing pilot transition training when the accident occurred. The second pilot stated that he was attempting to execute the second full touchdown autorotation, and "I was too high off the ground when I pulled the collective and hit the ground too hard." The first pilot, the Boeing Certified Flight Instructor (CFI), said that the second pilot was executing a straight in autorotation. As the autorotation was begun, the CFI stated that the rotor started low in the acceptable range, so he prompted the second pilot to further reduce the collective, and their rate of descent increased. The CFI stated the maneuver was still satisfactory, with a low flare. He stated that about 18 feet, the second pilot applied "60 percent collective, leveled somewhat, and the nose yawed to the left." At that point, the CFI said he applied full right pedal in an attempt to straighten the aircraft, but the nose remained yawed approximately 15 degrees to the left. The aircraft hit the ground with the left heel first, followed by the nose pitching forward. The CFI stated he applied slight aft cyclic, when he felt the main rotor contact the tailboom. According to the aircraft manufacturer, the touchdown resulted in a hard landing, which caused the main rotor blades to flex and contact the tailboom. The tailboom was subsequently fractured by the rotor blade contact. The aircraft remained upright and the engine was shutdown using the emergency shutdown procedures. ## Aircraft - Registration: N176SP (not matched to a registry record) - Reported make and model: McDonnell Douglas 600N - Category: Helicopter - Serial number: RN012 - Airframe hours: 13 - Engines: Allison 250-C47M 650 horsepower turbo shaft - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: West Virginia State Police - Airworthiness certificate: Standard, Normal - Departed: FFZ - Flight plan: Company VFR - Airport: FFZ, Falcon Field ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 49; commercial, flight instructor, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 12,726 total, 85 in this make and model, 12,053 as pilot in command, 95 in the last 90 days, 41 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 40° at 4 knots - Visibility: 30 statute miles - Lowest ceiling: 20,000 ft broken - Temperature: 64 °F - Altimeter: 30.00 inHg - Observed at: FFZ, 1 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19980116001469A](https://openairdocs.org/incident/19980116001469A), Jan 16, 1998: Doug 600N, Mesa, AZ, Substantial damage. Landed hard main rotor struck tailboom. (.4)the CFI was having the second pilot execute straight in aurorotations for familiarization training. The second… ## Docket (5 files) The files NTSB released with the investigation on September 1, 1998, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=30023. 814 KB in all. - Supplement S (item 1, .PDF, 119 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40390095&FileExtension=.PDF&FileName=Supplement%20S-Redacted.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1/2 (item 2, .PDF, 516 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40390096&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%2F2-Redacted.PDF - Aircraft Flight Records (item 3, .PDF, 63 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40390097&FileExtension=.PDF&FileName=Aircraft%20Flight%20Records-Redacted.PDF - Aircraft Registration (item 4, .PDF, 75 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40390098&FileExtension=.PDF&FileName=Aircraft%20Registration-Redacted.PDF - Aircraft Weight and Balance (item 5, .PDF, 41 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40390099&FileExtension=.PDF&FileName=Aircraft%20Weight%20and%20Balance-Redacted.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.