- Date
- March 12, 2017, 17:00 local (Mar 13, 2017, 00:00 UTC)
- Place
- Julian, CA
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Takeoff
- Aircraft
- N675THKaman Aerospace K 1200
- Defining event
- Takeoff: Part(s) separation from AC
- Weather
- Visual (VMC) · Day
- Status
- Completed · report September 22, 2017
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20170312002059A
- Case key
- 94737
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
The pilot’s failure to conduct a thru-flight walkaround inspection, which resulted in the engine cowling remaining open and subsequently separating from the helicopter and striking the main rotor blades and vertical stabilizer during departure.
Findings · 2
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.
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 pilot of the helicopter reported that he had landed and was going to reposition to another company landing zone after dropping off his crew chief. The pilot opened the engine cowling to allow the engine to cool before restart. However, the pilot did not perform a thru-flight walkaround inspection and climbed into the cockpit and took off. About 60 seconds after departure, he felt a large thump throughout the airframe and then landed as soon as practicable. Upon shutdown and inspection, he noticed that the engine cowling had departed the helicopter and struck the right two main rotor blades and the vertical stabilizer, which resulted in substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation. In the recommendations section of the National Transportation Safety Board Pilot Aircraft Accident Report, the pilot specified that the company has issued a policy that prohibits opening the engine cowling for the sole purpose of allowing the engine to cool. Additionally, the policy directed a pretakeoff helicopter inspection to be completed by a qualified technician.
Factual narrative
The pilot of the helicopter reported that he had landed and was going to reposition to another company landing zone after dropping of his crew chief. The pilot opened the engine cowling to allow the engine to cool before restart. However, the pilot did not perform a thru flight walk around and climbed in to the cockpit and took off. About sixty seconds after departure, he felt a large thump throughout the airframe and landed as soon as practicable. Upon shutdown and inspection, he noticed that the engine cowling had departed the helicopter and struck the right two main rotor blades and the vertical stabilizer. Substantial damage was sustained to the right main rotor blades and the vertical stabilizer. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. In the recommendations section of the National Transportation Safety Board Pilot Aircraft Accident Report, the pilot specified that the company has issued a policy that prohibits opening the engine cowling for the sole purpose of allowing the engine to cool. Additionally, the policy directed a pre-takeoff helicopter inspection to be completed by a qualified technician.
Aircraft
- Registration
- N675TH
- Reported as
- Kaman Aerospace K 1200 (NO SERIES)
- Category
- Helicopter
- Serial number
- A94-0025
- Built
- 1998
- Airframe hours
- 9,820.7
- Engine
- Honeywell T5317-A1, 1,500 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Positioning · Part 91
- Operator
- Timberline Helicopters Inc
- Registered owner
- Timberline Helicopters Inc
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · February 28, 2017
- Departed
- PVT · Julian, CA
- Destination
- PVT · Julian, CA
- Flight plan
- Company VFR
- Equipment
- Electronic multifunction display, Electronic flight bag or handheld device, Angle of attack indicator, Satellite tracking device, Onboard weather
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
- 54
- Injuries
- None
- Certificate
- Commercial
- Medical
- Class 2, With waivers/limitations
- Last flight review
- June 15, 2015
- Seat
- Single
- Flight hours
- 10,000 total · 4,760 in this make and model · 9,000 as pilot in command · 150 in the last 90 days · 45 in the last 30 days · 2 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 310° at 9 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 82 °F, dew point 52 °F
- Altimeter
- 29.96 inHg
- Observed at
- KRNM, 16 nm away
Docket · 2
The files NTSB released with the investigation on August 29, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 4.2 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.