Wednesday, September 06, 2017

Flight Control System Malfunction/Failure: Cobalt Co50 Valkyrie, N523CA; accident occurred September 05, 2017 at Castle Airport (KMER), Atwater, Merced County, California





The National Transportation Safety Board did not travel to the scene of this accident.


Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Fresno, California

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf 



Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N523CA

Location: Atwater, CA
Accident Number: WPR17LA201
Date & Time: 09/05/2017, 1430 PDT
Registration: N523CA
Aircraft: COBALT AIRCRAFT INDUSTRIES INC Co50 VALKYRIE
Aircraft Damage: Substantial
Defining Event: Flight control sys malf/fail
Injuries: 1 None
Flight Conducted Under: Part 91: General Aviation - Flight Test 

On September 05, 2017, about 1430 Pacific daylight time, an experimental Cobalt Co50 Valkyrie airplane, N523CA, landed hard at the Castle Airport, Atwater, California. The airline transport pilot was not injured; the airplane sustained substantial damage. The airplane was registered to and operated by Cobalt Aircraft Industries, Inc. as a Title 14 Code of Federal Regulations Part 91 test flight. Visual meteorological conditions prevailed and no flight plan was filed for the local area flight which originated from Atwater about 1405.

The airplane, serial number PX-04, was manufactured in October 2016 and registered under an Experimental Research and Development airworthiness certificate. The airplane had undergone four previous flights and the accident flight was the pilot's first flight in a Cobalt aircraft. The purpose of the flight was for the pilot to perform an evaluation of handling qualities at various configurations specified in the test card.

The pilot stated that he started the flight by making two test runs down the runway. During both test runs he briefly lifted the airplane off the surface in an effort to check the rotation performance. On both attempts, he had full aft back pressure on the control stick and the airplane would not rotate off the runway. The pilot determined that the center-of-gravity (CG) was too far aft and the ground team added 2o to the adjustable ground trim, equating to a total of 10o. The pilot configured the airplane for a departure from runway 31, planning for a rotation speed of 75 kts.

The pilot further stated that after rotation, with the airplane about 50 ft above ground level (agl), he experienced extreme difficulty controlling the airplane. As the airspeed increased, he began to attain some controllability and climbed to about 1,400 ft agl. He determined that the ailerons were ineffective but was able to use the rudder for directional control. The pitch stability was sporadic with him experiencing intermittent pitch up and down movements. After about 20 minutes of manipulating the flight controls and practicing climbing and descending using the trim, he managed to stabilize the airplane around 90 kts. He reasoned that he would be able to land the airplane while configured at an increased airspeed using steady thrust control and the rudder for directional control. During landing, with the airplane about 10 ft above the runway surface, the airplane experienced a loss of lift and landed hard. The impact resulted in the right landing-gear leg separating and the airplane subsequently made a 180o turn; the right-wing spar sustained damage.

A representative from Colbalt stated the company reviewed the video recordings and onboard recorders. The recordings disclosed that after a faster-than-expected rotation speed between 80-85 kts, the airplane had no roll control. For the test flight they had an increased weight and had changed the winglet position which contributed to a loss of aileron effectiveness. 

Pilot Information

Certificate: Airline Transport; Flight Instructor
Age: 73, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land; Single-engine Sea
Seat Occupied: Left
Other Aircraft Rating(s): Glider; Helicopter
Restraint Used:
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Glider
Toxicology Performed:No 
Medical Certification: Class 2 Without Waivers/Limitations
Last FAA Medical Exam: 05/01/2017
Occupational Pilot: Yes
Last Flight Review or Equivalent:
Flight Time:   (Estimated) 9650 hours (Total, all aircraft), 0.8 hours (Total, this make and model), 7500 hours (Pilot In Command, all aircraft), 6.3 hours (Last 90 days, all aircraft), 6.3 hours (Last 30 days, all aircraft), 0.8 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: COBALT AIRCRAFT INDUSTRIES INC
Registration: N523CA
Model/Series: Co50 VALKYRIE
Aircraft Category: Airplane
Year of Manufacture: 2016
Amateur Built: No
Airworthiness Certificate: Experimental
Serial Number: P04
Landing Gear Type: Retractable - Tricycle
Seats: 5
Date/Type of Last Inspection: 09/04/2017, Continuous Airworthiness
Certified Max Gross Wt.: 3417 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 1 Hours at time of accident
Engine Manufacturer: CONTINENTAL MOTORS
ELT: Not installed
Engine Model/Series: TSIOF550-D
Registered Owner: COBALT AIRCRAFT INDUSTRIES INC
Rated Power: 350 hp
Operator: COBALT AIRCRAFT INDUSTRIES INC
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KMER, 191 ft msl
Distance from Accident Site: 1 Nautical Miles
Observation Time: 1415 PDT
Direction from Accident Site: 34°
Lowest Cloud Condition: Clear
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 7 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 340°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 29.85 inches Hg
Temperature/Dew Point: 24°C / 18°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Atwater, CA (MER)
Type of Flight Plan Filed: None
Destination: Atwater, CA (MER)
Type of Clearance: VFR
Departure Time: 1405 PDT
Type of Airspace:

Airport Information

Airport: CASTLE (MER)
Runway Surface Type: Asphalt; Concrete
Airport Elevation: 190 ft
Runway Surface Condition: Dry
Runway Used: 31
IFR Approach:None 
Runway Length/Width: 11802 ft / 150 ft
VFR Approach/Landing: Full Stop 

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 37.375833, -120.573056 (est)

Location: Atwater, CA
Accident Number: WPR17LA201
Date & Time: 09/05/2017, 1430 PDT
Registration: N523CA
Aircraft: COBALT AIRCRAFT INDUSTRIES INC Co50 VALKYRIE
Injuries: 1 None
Flight Conducted Under:  Part 91: General Aviation - Flight Test 

On September 05, 2017, about 1430 Pacific daylight time, a Cobalt Co50 Valkyrie, N523CA, landed hard following an in-flight loss of controllability at the Castle Airport, Atwater, California. Cobalt Aircraft Industries, Inc., was the registered owner and was operating the airplane under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The airline transport pilot, the sole occupant, was not injured; the airplane sustained substantial damage. The local-area test flight originated from Atwater about 1410. Visual meteorological conditions prevailed and no flight plan was filed.

The airplane, serial number PX-04, was manufactured in October 2016 and registered under an Experimental Research and Development airworthiness certificate. The airplane had undergone four previous flights and the accident flight was the pilot's first flight in a Cobalt aircraft. The purpose of the flight was for the pilot to perform an evaluation of handling qualities at various configurations specified in the test card.

The pilot stated that immediately after rotation, he experienced extreme difficulty controlling the airplane. As the airspeed increased, he began to attain some controllability and climbed to about 1,000 feet above ground level. He determined that the ailerons were ineffective but was able to use the rudder for directional control. The pitch stability was sporadic with him experiencing intermittent pitch up and down movements. After about 20 minutes of manipulating the flight controls and practicing climbing and descending using the trim, he managed to stabilize the airplane around 90 kts. He reasoned that he would be able to land the airplane while configured at an increased airspeed using steady thrust control and the rudder for directional control. During landing, with the airplane about 10 feet above the runway surface, the airplane experienced a loss of lift and landed hard. The impact resulted in the right landing-gear leg separating and the airplane subsequently made a 180-degree; the right-wing spar sustained damage. 

Aircraft and Owner/Operator Information

Aircraft Manufacturer: COBALT AIRCRAFT INDUSTRIES INC
Registration: N523CA
Model/Series: Co50 VALKYRIE
Aircraft Category: Airplane
Amateur Built: No
Operator: COBALT AIRCRAFT INDUSTRIES INC
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KMER, 191 ft msl
Observation Time: 1415 PDT
Distance from Accident Site: 1 Nautical Miles
Temperature/Dew Point: 24°C / 18°C
Lowest Cloud Condition: Clear
Wind Speed/Gusts, Direction: 7 knots, 340°
Lowest Ceiling: None
Visibility:  10 Miles
Altimeter Setting: 29.85 inches Hg
Type of Flight Plan Filed: None
Departure Point: Atwater, CA (MER)
Destination: Atwater, CA (MER) 

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude:  37.375833, -120.573056 (est)

5 comments:

  1. Well, here we go again. A lot of great press and hype about an aircraft that liberates us from our humdrum cessnas, moonies and whatnots.

    And then reality, or aerodynamics and phisics brings us down to earth. Nevermind the sleek styling and hand stitched seats, we have another unstable plane. And more evidence tha engine in nose and normal configuration are the prudent way to fly.

    One would think the canard approach would be dead by now but here we are again.

    ReplyDelete
  2. Cobalt "Recent News" stopped in February 2016 -with CNN aka Fake News;
    Cobalt Facebook last posting was back in October 2016;

    No updates about the "design-centric, stunningly sleek, modern, as well as super fast, safe and easy to fly", not in any of the aviation magazines, websites nor from the company.

    Cobalt = Fail

    ReplyDelete
  3. Very impressed with pilot's ability to immediately "teach" himself previously unfamiliar flight control paradigm. Amazing skill set. Congratulations to him! What airline does he fly for?

    Re: the problem??? What did the analysis reveal about he cause of aileron failure... wiring or pulley failure interfering with pushrod/bellcrank/control cable function??

    Would be interesting to know what about the take-off run and rotation resulted in aileron/stick disconnect... hard to imagine this behavior getting by even a cursory preflight inspection.

    Love the plane and the specs. Hope the problem was obvious, fixed, and the effort to bring this plane to life is back on track.

    Lack of PR suggests the contrary. If they are still working to make this happen they should communicate with full disclosure what is happening. Only way to achieve confidence and validity for the revolutionary product.

    Good luck to Cobalt!

    ReplyDelete
  4. Yes I agree. With one’s life on the line , there is focus and a degree of calm. Now snap back to reality and figure out how u can land this thing before the inevitable happens. I would have turn the beast around and landed immediately. So hats off to the pilot.

    ReplyDelete
  5. The project continues:
    https://www.centauri-aircraft.com/

    Flight Video, July 2020:
    https://youtu.be/wzUJNISpf2w

    ReplyDelete