WPR15LA261

NTSB accident investigation · Schweizer 269C · Forest Grove, OR · September 18, 2015

Accident · Minor injuriesLimited investigationFinal report
Date
September 18, 2015, 08:15 local (15:15 UTC)
Place
Forest Grove, OR
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N290RSchweizer 269C
Defining event
Maneuvering-low-alt flying: Loss of engine power (partial)
Weather
Visual (VMC) · Day
Status
Completed · report July 11, 2016
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration, Sikorsky Aircraft Corp.
FAA report
20150918016019A
Case key
91996

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

On this page

Probable cause

A partial loss of engine power during cruise flight for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

Findings · 1

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Not determinedNot determined › Not determined · Unknown/Not determinedSchweizer 269C: 6 casesAll aircraft: 2,247 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The commercial pilot reported that, during low-altitude cruise while conducting a positioning flight and with the helicopter about 40 knots and 55 ft above ground level, the engine lost power, and the helicopter began to lose altitude. During the subsequent autorotation, the helicopter struck some wires near the ground, which resulted in a dynamic rollover. The helicopter came to rest on its left side nearly inverted. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Further, the engine was test run at a low-power setting with no anomalies noted.

Factual narrative

On September 18, 2015, about 0815 Pacific daylight time, a Schweizer 269C helicopter, N290R, sustained substantial damage during an off field landing, near Forest Grove, Oregon. The helicopter was registered to and operated by Oregon Roses Inc., under the provisions of Title 14 Code of Federal Regulations Part 91. The commercial pilot, sole occupant of the helicopter, sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the positioning flight. The local flight originated from a private helipad about 0814. The pilot reported that during low altitude cruise to a nearby landing site, where it was planned to take on chemical spray, the engine lost power and the helicopter began to lose altitude. At the time, the pilot was flying about 40 knots and approximately 55 feet above ground level. During the auto-rotation, the helicopter struck some wires near the ground, which resulted in a dynamic rollover, and the helicopter came to rest on its left side, nearly inverted. Postaccident examination of the helicopter by a Federal Aviation Administration (FAA) inspector revealed that the main rotor blades and tail boom were substantially damaged. The helicopter was recovered to a secure local storage facility for further examination. Further examination of the helicopter by the National Transportation Safety Board investigator-in-charge, an FAA inspector, a Sikorsky Investigator, and a certified Airframe and Powerplant (A&P) mechanic revealed no evidence of any internal damage to the engine or its accessories. The oil dipstick reading indicated a quantity of 6 quarts. The exhaust remained attached and was intact. Continuity of all the engine controls was established. The lower spark plugs were removed and examined and all sparkplug electrodes exhibited normal wear signatures when compared to the Champion Check-A-Plug comparison chart. The crankshaft was rotated by hand and compression was obtained on all the cylinders. It was determined that an engine run could be safety accomplished. The engine was subsequently test run and functioned normally at a low power setting. The magnetos were switched from left to right and the corresponding RPM drop was observed during the run. The Sikorsky investigator and the certified A&P mechanic stated that the engine ran smoothly and that they observed no engine anomalies. The engine run was accomplished at a low power setting only, due to concerns over the damage sustained to the mast support structure and the helicopter's overall stability, after the removal of the main rotor blades and tail boom. The helicopter's main transmission, gear boxes, drive shafts, and rotor heads were examined and no anomalies were noted with the exception of the tail rotor drive shaft that was separated by a main rotor blade strike, just aft of the vertical stabilizer mounting point. Tail rotor drive continuity was established to the point where the tail boom was separated, and from the separationpoint to the tail rotor gearbox. Flight control continuity was established with the cyclic and collective. The electric cyclic trim system was operated during the exam with no anomalies noted. Examination of the fuel system revealed that the helicopter was equipped with a 49 gallon fuel tank. The tank sustained damage to the aft, outboard portion but remained intact, with no loss of fuel. The fuel screen was removed, and there was fuel in the screen housing. The screen was observed to be clean of debris. Fuel samples from the storage tank and helicopter were taken and later tested by the FAA using a water detection paste, with negative results. A review of the helicopter's maintenance records revealed that the engine and airframe underwent their most recent annual inspection on September 08, 2015, at an airframe total time of 2,050.9 hours. The time since the overhaul of the engine was 494.2 hours.

Aircraft

Registration
N290R
Reported as
Schweizer 269C (UNDESIGNAT)
Category
Helicopter
Serial number
S1537
Built
1991
Airframe hours
2,050.9
Engine
Lycoming HIO-360-D1A, 190 horsepower, reciprocating
Damage
Substantial damage
Flight
Positioning · Part 91
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · April 30, 2015
Departed
Forest Grove, OR
Destination
Forest Grove, OR
Equipment
None

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
52
Injuries
Minor
Certificate
Commercial
Medical
Class 2, Without waivers/limitations
Last flight review
March 13, 2014
Seat
Left
Restraint
3-point
Flight hours
872 total · 812.4 in this make and model · 672 as pilot in command

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
10 statute miles
Lowest ceiling
None
Temperature
48 °F, dew point 46 °F
Altimeter
30.13 inHg
Observed at
KHIO, 7 nm away

Docket · 5

The files NTSB released with the investigation on May 24, 2016, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.5 MB 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.