LAX98LA076

NTSB accident investigation · McDonnell Douglas 600N · Mesa, AZ · January 17, 1998

Accident · No injuriesLimited investigationFinal report
Date
January 16, 1998, 17:30 local (Jan 17, 1998, 00:30 UTC)
Place
Mesa, AZ
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N176SPMcDonnell Douglas 600N
Weather
Visual (VMC) · Day
Status
Completed · report February 15, 2001
Report
Approved by Office Director
FAA report
19980116001469A
Case key
30023

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The second pilot misjudging his flare and the delayed remedial actions by the pilot-in-command.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Hard landingLanding - flare/touchdown
Misc rotorcraft,main rotor/tail boom contact
Terrain condition - grass
Flare - misjudgedPilot in commandCause
Remedial action - delayedPilot 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
Reported as
McDonnell Douglas 600N
Category
Helicopter
Serial number
RN012
Airframe hours
13
Engine
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.

Role
Pilot
Age
49
Certificates
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

Docket · 5

The files NTSB released with the investigation on September 1, 1998, on NTSB’s docket system: statements, records, photos and specialists’ reports. 814 KB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.