Sunday, October 11, 2020

Low Altitude Operation/Event: Sonex, N612RF; accident occurred October 11, 2019 at Whidbey Air Park (W10), Langley, Island County, Washington


Additional Participating Entity: 
Federal Aviation Administration / Flight Standards District Office; Des Moines, Washington

Aviation Accident Final Report - National Transportation Safety Board:

Investigation Docket - National Transportation Safety Board:

Location: Langley, WA
Accident Number: GAA20CA018
Date & Time: 10/11/2019, 1530 PDT
Registration: N612RF
Aircraft Damage: Substantial
Defining Event: Low altitude operation/event
Injuries: 1 Serious
Flight Conducted Under: Part 91: General Aviation - Flight Test


The pilot reported that, while on left base leg in the traffic pattern, the airplane was high. He made a 270° descending right turn to final and added 20° of flaps. The airplane descended faster than expected, and the left wing struck a tree. The airplane then impacted terrain and came to rest inverted, and a postcrash fire ensued. The airplane sustained substantial damage to the fuselage and both wings. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. 

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's failure to maintain a proper approach path, which resulted in impact with a tree. 


Descent/approach/glide path - Not attained/maintained (Cause)

Personnel issues
Aircraft control - Pilot (Cause)

Environmental issues
Tree(s) - Effect on operation (Cause)

Factual Information

History of Flight

Low altitude operation/event (Defining event)

Collision with terr/obj (non-CFIT)

Pilot Information

Certificate: Sport Pilot
Age: 65, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Left
Other Aircraft Rating(s): None
Restraint Used:
Instrument Rating(s): None
Second Pilot Present: No
Instructor Rating(s): None
Toxicology Performed: No
Medical Certification: Sport Pilot
Last FAA Medical Exam:
Occupational Pilot: No
Last Flight Review or Equivalent: 04/23/2019
Flight Time:  (Estimated) 160.4 hours (Total, all aircraft), 1.8 hours (Total, this make and model), 160.4 hours (Pilot In Command, all aircraft), 4.3 hours (Last 90 days, all aircraft) 

Aircraft and Owner/Operator Information

Registration: N612RF
Model/Series: SONEX
Aircraft Category: Airplane
Year of Manufacture: 2014
Amateur Built: Yes
Airworthiness Certificate: Experimental
Serial Number: 1559
Landing Gear Type: Tricycle
Seats: 1
Date/Type of Last Inspection:  Unknown
Certified Max Gross Wt.: 1150 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 4.5 Hours at time of accident
Engine Manufacturer: Aerovee
ELT: C91A installed, activated, aided in locating accident
Engine Model/Series: Aerovee 2.1
Registered Owner: On file
Rated Power: 80 hp
Operator: On file
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KPAE, 606 ft msl
Distance from Accident Site: 9 Nautical Miles
Observation Time: 2253 UTC
Direction from Accident Site: 136°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 3 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 340°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.1 inches Hg
Temperature/Dew Point: 16°C / -1°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Langley, WA (W10)
Type of Flight Plan Filed: None
Destination: Langley, WA (W10)
Type of Clearance: None
Departure Time: 1500 PDT
Type of Airspace: Class G

Airport Information

Airport: Whidbey Air Park (W10)
Runway Surface Type: Asphalt
Airport Elevation: 271 ft
Runway Surface Condition:
Runway Used: 34
IFR Approach: None
Runway Length/Width: 2470 ft / 25 ft
VFR Approach/Landing: Full Stop; Traffic Pattern

Wreckage and Impact Information

Crew Injuries: 1 Serious
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: On-Ground
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Serious
Latitude, Longitude: 48.017500, -122.437778 (est)


  1. '1.8 hours Total, this SONEX make and model and 4.3 hours Last 90 days, all aircraft' Taken from the Sonex Builders & Pilots Foundation Transition-Training Syllabus "Truth #2 (of 9) – This ain't your father's Cessna (or Piper, or Beechcraft, etc.) Pilots whose sole experience has been in general aviation aircraft have found the Sonex to be a whole new world in control feel. It takes a while to get comfortable with flying the airplane with JUST the fingertips. You don't have to hold on tight when the control pressures are light and the airplane is responsive. This is probably the steepest learning curve I've run into. Pilots who have flown light-sport aircraft, or have experience in other homebuilt designs are better prepared to get in tune with the Sonex' responsive handling."

    1. ^^That. I've seen ex-mil and retired airline pilots get themselves in trouble with kit/LSA class aircraft. Just because it is lower powered and slower than what you are used to does not mean it can't get you killed.

    2. As someone who has recently transitioned to E-LSA, I can confirm that. The flight characteristics of an RV-12 (in my example) are considerably different than your standard Archer or 172. There are key areas where they behave differently, and this takes getting used to. I spend about 7 hours transitioning, and it was well worth it. You would think that a plane that does 65 in the pattern would be easy to fly at hour 0, but that is not the case if you expect it to act like a Piper. Transition training is very important.