ANC93LA158

NTSB accident investigation · Hughes 369D · Mount Iliamna, AK · August 28, 1993

Accident · No injuriesLimited investigationFinal report
Date
August 27, 1993, 19:20 local (Aug 28, 1993, 03:20 UTC)
Place
Mount Iliamna, AK
Injuries
5 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N5074RHughes 369D
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 1994
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19930827031619A
Case key
2414

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 pilot's improper in-flight planning/decision, and his delay in taking remedial action. Factors were the mountainous terrain and gusty winds.

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.

In flight collision with terrain/waterManeuvering - turn to reverse direction
Terrain condition - mountainous/hillyFactor
In-flight planning/decision - improperPilot in commandCause
Weather condition - gustsFactor
Remedial action - delayedPilot in commandCause

Analysis

After making a low pass over a mountainous work site the helicopter started a right turn. The pilot said he soon realized that the helicopter would not be able to out climb the steep terrain, so he started a turn back to the left. Then the right skid hit the mountainside, causing the skid and the right half of the crosstubes to be torn from the airframe. Some additional damage was also sustained by the fuselage. The helicopter returned to its nearby base camp and landed on a makeshift support structure. The pilot said he might have encountered a downdraft. The pilot and four passengers said the winds were gusty at the time of the accident.

Factual narrative

On August 27, 1993, at 1920 Alaska daylight time, a skid equipped Hughes 369D helicopter, N5074R, operated by Soloy Helicopters, Inc., of Wasilla, Alaska, collided with the terrain while maneuvering just northeast of Mount Iliamna, Alaska. The commercial pilot and 4 passengers were not injured, and the helicopter sustained substantial damage. The unscheduled domestic passenger flight, operating under 14 CFR Part 135, departed a remote camp in the area about 5 minutes before the accident. Visual meteorological conditions existed, and a company VFR flight plan was filed.

Shortly after the accident, during a telephone interview, the pilot stated the following in part: "I had just taken off from the driller's base camp, and had made a low pass over the drill rig about 2 miles away to see if anyone there needed us for anything. I started a right turn then realized that I wouldn't be able to out climb the steep mountain, so turned back to the left. Then the right skid hit the mountainside causing the skid and crosstubes to be separated from the helicopter. The fuselage belly was also damaged. I flew back to the base camp where I landed on a makeshift support structure. I could have encountered a downdraft that caused the helicopter to settle down and hit the mountainside."

Aircraft

Registration
N5074R
Reported as
Hughes 369D
Category
Helicopter
Serial number
1151D
Airframe hours
6,624
Engine
Allison 250-C20B, 420 horsepower, turbo shaft
Damage
Substantial damage
Flight
Part 135
Operator
Soloy Helicopters, Inc.
Registered owner
Soloy Helicopters, Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · August 11, 1993 · 81 hours before
Flight plan
Company VFR

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
46
Certificates
Commercial, Private
Airplane ratings
Single-engine land
Instrument ratings
Helicopter
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Left
Toxicology
Performed
Flight hours
5,650 total · 3,600 in this make and model · 5,540 as pilot in command · 270 in the last 90 days · 110 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
180° at 10 knots, gusting 15
Visibility
20 statute miles
Lowest ceiling
10,000 ft overcast
Temperature
61 °F

FAA reports on this event · 1

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