Sunday, April 18, 2021

Aerodynamic Stall / Spin: Rans S-7 Courier, N25TX; fatal accident occurred April 21, 2019 at Shirley Williams Airport (44TE), Kingsland, Llano County, Texas

John Timothy Sharpe
January 9, 1953 - April 21, 2019
Austin and Kingsland, Texas
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Aviation Accident Factual Report - National Transportation Safety Board 

The National Transportation Safety Board traveled to the scene of this accident.

Additional Participating Entities:
Federal Aviation Administration / Flight Standards District Office; San Antonio, Texas
Austrian Ministry for Transport 
Rotech Flight Safety

Investigation Docket - National Transportation Safety Board: 


Location: Kingsland, Texas
Accident Number: CEN19FA122
Date & Time: April 21, 2019, 14:43 Local
Registration: N25TX
Aircraft: Rans S7 Aircraft
Damage: Destroyed
Defining Event: Aerodynamic stall/spin 
Injuries: 2 Fatal
Flight Conducted Under: Part 91: General aviation - Personal

On April 21, 2019, at 1443 central daylight time, a Rans S-7S airplane, N25TX, was destroyed when it was involved in an accident near Kingsland, Texas. The pilot and passenger were fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

A witness reported that the pilot had just completed a few touch-and-go landings at Shirley Williams Airport before the passenger boarded the airplane. He saw the airplane taxi back to the runway, then heard it impact the ground shortly thereafter.

Another witness reported observing what he considered a "normal" takeoff, followed by a steep 15 to 20 second climb. At the top of the climb, the nose and left wing suddenly dropped, and the airplane entered a left-turning spiral, completing 3 to 4 slow rotations before impact with the ground. He stated that the engine sounded normal the whole time and he did not notice anything wrong.

Pilot Information

Certificate: Commercial; Private
Age: 66, Male
Airplane Rating(s): Single-engine land 
Seat Occupied: Front
Other Aircraft Rating(s): Balloon 
Restraint Used: Unknown
Instrument Rating(s): None 
Second Pilot Present: Yes
Instructor Rating(s): None 
Toxicology Performed: Yes
Medical Certification: Class 3 With waivers/limitations 
Last FAA Medical Exam: December 30, 2017
Occupational Pilot: No 
Last Flight Review or Equivalent:
Flight Time: 215 hours (Total, all aircraft)

Pilot-rated passenger Information

Certificate: Private Age: 65, Male
Airplane Rating(s): Single-engine land 
Seat Occupied: Rear
Other Aircraft Rating(s): None
Restraint Used: Unknown
Instrument Rating(s): None
Second Pilot Present: Yes
Instructor Rating(s): None
Toxicology Performed: Yes
Medical Certification: Class 3 With waivers/limitations 
Last FAA Medical Exam: August 13, 2002
Occupational Pilot: No
Last Flight Review or Equivalent:
Flight Time: 180 hours (Total, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: Rans 
Registration: N25TX
Model/Series: S7 S 
Aircraft Category: Airplane
Year of Manufacture: 2005 
Amateur Built: Yes
Airworthiness Certificate: Experimental (Special); Experimental light sport (Special)
Serial Number: 0304369
Landing Gear Type: Tailwheel
Seats: 2
Date/Type of Last Inspection: November 8, 2018 Condition
Certified Max Gross Wt.: 1320 lbs
Time Since Last Inspection: 28.9 Hrs
Engines: 1 Reciprocating
Airframe Total Time: 188.6 Hrs as of last inspection
Engine Manufacturer: Rotax
ELT: Engine Model/Series: 912S ULS
Registered Owner: 
Rated Power: 100 Horsepower
Operator: On file
Operating Certificate(s) Held: None

According to the second witness who observed the accident, in March 2019, the pilot and passenger (who was also a mechanic) had completed maintenance work on the carburetors and synchronized them so that the engine ran smooth. The week before the accident, the pilot and passenger had dinner with the witness and told him that they were troubleshooting an issue where the engine would sputter during steep climbs. They told the witness that they cleaned the gascolator, checked the fuel lines, and verified that the propeller was adjusted correctly. The witness stated that, 1 day before the accident, the pilot flew the airplane with another passenger, but they just flew to get lunch and did not attempt any steep climbs. The pilot reported to him that the engine operated with no issues. The witness further stated that, on the day of the accident, the pilot's plan was to perform steep climbs and try to figure out why the engine was sputtering. The witness did not know if the accident flight was the first troubleshooting flight.

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual (VMC)
Condition of Light: Day
Observation Facility, Elevation: KDZB,1093 ft msl
Distance from Accident Site: 9 Nautical Miles
Observation Time: 
Direction from Accident Site: 163°
Lowest Cloud Condition: 
Visibility: 10 miles
Lowest Ceiling: 
Visibility (RVR):
Wind Speed/Gusts: 15 knots / 25 knots 
Turbulence Type Forecast/Actual:  /
Wind Direction: 180° 
Turbulence Severity Forecast/Actual:  /
Altimeter Setting: 
Temperature/Dew Point:
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Kingsland, TX (44TE)
Type of Flight Plan Filed: None
Destination: Kingsland, TX (44TE)
Type of Clearance: None
Departure Time: 14:42 Local
Type of Airspace: Class G

Airport Information

Airport: Shirley Williams 44TE
Runway Surface Type: Grass/turf
Airport Elevation: 880 ft msl 
Runway Surface Condition: Dry
Runway Used: 16 
IFR Approach: None
Runway Length/Width: 2600 ft / 100 ft
VFR Approach/Landing: None

Wreckage and Impact Information

Crew Injuries: 2 Fatal
Aircraft Damage: Destroyed
Passenger Injuries:
Aircraft Fire: On-ground
Ground Injuries: N/A
Aircraft Explosion: On-ground
Total Injuries: 2 Fatal
Latitude, Longitude: 30.678333,-98.417503

The airplane departed on runway 16 and impacted the ground near the south end of the runway, as seen in figure 1.

Figure 1 – Aerial image of the accident site


The accident site consisted of a small initial impact point in the ground about 20 ft south of the main wreckage. The impact point was defined by a divot in the ground which contained a broken red lens, the pitot tube, and a piece of left wing tip. Another impact area was about 6 ft south of the main wreckage, which was about 3 ft in diameter and about 4 inches deep. The small crater contained white paint chips, plexiglass, a propeller blade, and the engine oil filter. Another small divot was observed under the outboard leading edge of the right wing. The three impact areas were in a relatively straight line in a north-south orientation. The airplane came to rest upright facing southwest and was mostly consumed by postcrash fire. An examination of the airframe did not reveal any anomalies that would have precluded normal operation.

The engine remained attached to the engine mounts, which were broken from the airframe. The engine was mostly intact and severely damaged by fire. The propeller hub remained attached to the crankshaft and one blade remained attached to the hub. The second blade was broken from the hub at the blade root and was found next to the initial engine impact crater – it exhibited chordwise scratches on the face. The third blade was also broken from the hub at the blade root and was found about 20 ft west of the main wreckage – it exhibited chordwise scratches and the blade tip was separated. The engine was examined at a secure facility and exhibited significant thermal damage from the postimpact fire. The fuel pump was partially consumed by the fire and a full examination was not possible. 
According to the engine manufacturers guidance and the fuel pump serial number, the fuel pump had a five-year time limit and should have been replaced in 2010.

The engine did not reveal any anomalies that would have preclude normal operation; however, the examination was limited due to the thermal damage.

Medical and Pathological Information

An autopsy of the pilot was performed by Travis County Medical Examiner, Austin, Texas. The cause of death was blunt force injuries.

Toxicology testing of specimens from the pilot, performed by the FAA Forensic Sciences Laboratory, identified three previously reported medications: amlodipine, hydrochlorothiazide, and rosuvastatin.

Also present were two other medications: naproxen and salicylate. These medications would not have posed a hazard to the safety of flight.

An autopsy of the pilot-rated passenger was performed by Travis County Medical Examiner, Austin, Texas. The cause of death was blunt force injuries.

Toxicology testing of specimens from the pilot-rated-passenger did not identify any drugs or tested-for substances.






6 comments:

  1. Flying with known issues. Tragic.

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  2. Well dang! Practice them steep climbs a little higher, say 3,000 feet. That’ll give you some room for spin recovery. At least they died from the stall and fall and weren’t roasted to death. Boys, really need to learn a lesson from this stuff. If it won’t fly safely, stay on the ground. If you want to practice flying in the air, put some air under you. RIP brothers.

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    1. Kind of harsh, but you are absolutely correct, why was he doing such steep climbs on an iffy engine right after takeoff. If he was testing the engine to see if it would sputter during a steep climb. He should have done it a safe recoverable altitude. A tragic outcome for them, and their families, and my condolences to their families, be safe everybody.

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  3. Witness stated the engine sounded fine. Perhaps the pax shifted the CG aft = steep climb attitude? Trim wasn't reset after pax boarded?

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    Replies
    1. Maybe they had "troubleshooting fixation". If it ran smooth on the first couple of tries, adding pax load and pulling up closer and closer to stall is the predictable progression, even if trimmed correctly. No room for error.

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