FTW96FA279

NTSB accident investigation · Prevatt RV-6 · Boulder, CO · June 29, 1996

Accident · FatalField investigationFinal report
Date
June 29, 1996, 14:50 local (20:50 UTC)
Place
Boulder, CO
Injuries
2 fatal, 2 uninjured
Phase of flight
Enroute
Aircraft
N194JPPrevatt RV-6N103LMBurkhart Grob G103C Twin III Acro
Weather
Visual (VMC) · Day
Status
Completed · report February 18, 1997
Report
Approved by Office Director
Case key
19652

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

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Probable cause

Poor judgment by the pilot of the RV-6, N194JP, in that he traversed an uncontrolled airport at traffic pattern altitude, failure of the pilots of both airplanes to see and avoid each other, and an inadvertent airplane stall encountered by the pilot of the RV-6 while maneuvering for an emergency landing.

Poor judgment by the pilot of the RV-6, N194JP, in that he traversed an uncontrolled airport at traffic pattern altitude, failure of the pilots of both airplanes to see and avoid each other, and an inadvertent airplane stall encountered by the pilot of the RV-6 while maneuvering for an emergency landing.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Midair collisionCruise
Judgment - poorPilot in commandCause
Altitude - improperPilot in commandCause
Visual lookout - inadequatePilot in commandCause
Visual lookout - inadequatePilot of other aircraftCause
Evasive maneuver - performedPilot of other aircraft
Loss of control - in flightManeuvering - turn to landing area (emergency)
Stall - inadvertentPilot in commandCause
In flight collision with terrain/waterDescent - uncontrolled
Midair collisionCruise - normal
Judgment - poorPilot of other aircraftCause
Altitude - improperPilot of other aircraftCause
Visual lookout - inadequatePilot in commandCause
Visual lookout - inadequatePilot of other aircraftCause
Evasive maneuver - performedPilot in command

Analysis

The pilot of the RV-6, N194JP, was crossing over the airport at traffic pattern altitude (6,100 feet msl, 812 feet agl) en route to Englewood, Colorado. The pilot of the glider, N103LM, was approaching the airport at pattern altitude and was getting ready to turn onto the downwind leg. The front seat passenger in the glider yelled that there was an approaching airplane directly in front. The pilot of the glider made a steep left bank and deployed his dive brakes in an evasive maneuver. According to witnesses, the glider's right wing tip struck the approaching RV-6's propeller, right main wheel, and lower cowling. The glider continued the left bank and landed safely. The RV-6 was seen to make a steep right bank and fly towards the northwest. The pilot of the RV-6 transmitted a distress call on the UNICOM frequency. Witnesses then observed the RV-6 to make a steep left turn, stall, and impact a lake near the runway threshold.

The pilot of the RV-6, N194JP, was crossing over the airport at traffic pattern altitude (6,100 feet msl, 812 feet agl) en route to Englewood, Colorado. The pilot of the glider, N103LM, was approaching the airport at pattern altitude and was getting ready to turn onto the downwind leg. The front seat passenger in the glider yelled that there was an approaching airplane directly in front. The pilot of the glider made a steep left bank and deployed his dive brakes in an evasive maneuver. According to witnesses, the glider's right wing tip struck the approaching RV-6's propeller, right main wheel, and lower cowling. The glider continued the left bank and landed safely. The RV-6 was seen to make a steep right bank and fly towards the northwest. The pilot of the RV-6 transmitted a distress call on the UNICOM frequency. Witnesses then observed the RV-6 to make a steep left turn, stall, and impact a lake near the runway threshold.

Factual narrative

See narrative for FTW 96-F-A279A.

History of flight

On June 29, 1996, approximately 1450 mountain daylight time, N194JP, a Prevatt RV-6, collided in midair with N103LM, a Burkhart Grob G103C Twin III Acro, in the traffic pattern at Boulder, Colorado, Municipal Airport. N194JP was destroyed and N103LM sustained minor damage. The private pilot and student pilot rated-passenger aboard N194JP were fatally injured. The private pilot and passenger aboard N103LM were not injured. Visual meteorological conditions prevailed, and neither pilot had filed a flight plan. Both personal flights were being conducted under Title 14 CFR Part 91. The flight of N194JP originated at Longmont, Colorado, on June 29, 1996, approximately 1440. The flight of N103LM originated at Boulder, CO, on June 29, 1996, approximately 1400.

According to the pilot of N103LM, his passenger was feeling airsick and wanted to return to the airport. The pilot approached the Boulder Municipal Airport (an uncontrolled airport) from the south at 6,100 feet msl (mean sea level) or 812 feet agl (above ground level), which is the traffic pattern altitude. He observed a two-airplane formation pass his right wing, going in the opposite direction at the same altitude. He wondered why they had crossed the airport at traffic pattern altitude. His front seat passenger then yelled there was an approaching airplane directly in front. The pilot made a steep left bank and deployed his dive brakes in an evasive maneuver. According to witnesses, N103LM's right wing tip struck N194JP's propeller, right main wheel, and lower cowling. N103LM continued the left bank and landed safely on runway 8R. N194JP was seen to make a steep right bank and fly towards the northwest. The pilot transmitted a distress call on the UNICOM frequency. Witnesses said the airplane then made a steep left turn, stalled, rolled inverted, and impacted Hayden Lake near the runway threshold.

The pilot of the lead airplane in the formation stated that he was flying a Pitts S-1, N11PJ. His wingman, who was to his right and slightly aft, was in an Acro Sport-1, N1717. They had attended an open house and air show at the Longmont Airport. The student pilot rated-passenger aboard N194JP was related to him by marriage. It was decided the pilot of N194JP and his passenger would spend the night at his home. The three airplanes departed approximately 1445 en route to Centennial Airport, Englewood, Colorado. Their planned route of flight was from Longmont, CO, to Boulder, CO; to Golden, CO; to Chatfield Reservoir; to Centennial Airport. He said that N194JP was not part of the formation, but was following them. After the collision, the two airplanes landed at Boulder Airport.

Personnel information

According to FAA records, the pilot of N194JP was issued his Private Pilot certificate on September 2, 1988, and a Repairman Certificate on January 4, 1995. The first entry in his logbook was dated March 6, 1988, and the last entry was dated June 22, 1996. During this time, the pilot had logged 317.7 total flight hours, 88.2 hours of which were in the RV-6. A personal friend of the pilot's said that he had also accrued 83 hours in hang gliders and approximately 200 to 300 hours in ultralights. His passenger was issued a Student Pilot certificate on May 10, 1995. He did not report any flight time logged when he applied for the 3rd class medical and his logbook was never located. For more information on certification data and aeronautical experience of the two pilots, see "Flight Time Matrix" in FTW 96-F-A279A. For certification data and aeronautical experience for the pilot of N103LM, see FTW 96-F-A279B, "Flight Time Matrix."

Aircraft information

According to the data plate affixed to the airplane, the pilot completed work on N194JP in November 1994. The airplane had an empty weight of 994 pounds and a gross weight 1,600 pounds. The airplane had flown 17 hours since its last annual conditional inspection conducted on January 1, 1996. At the time of the accident, the airplane had accrued 90 flight hours.

Wreckage and impact information

The inverted airplane was examined on the east shore of Hayden Lake after having been pulled ashore. Notwithstanding the following, the airplane was intact and control continuity was established throughout. There was compression type wrinkles on the top and bottom of both wings. The left wing tank was full of fuel. The partially filled right tank had separated from the wing, was found floating in the lake, and was retrieved. The right flap was separated from the wing, and the left aileron was detached at the outboard hinge. Measurements made indicate the flaps were deployed 20 degrees. The tail wheel was compressed into the bottom of the fuselage.

The bottom portion of the fiberglass cowling had been ripped away, exposing the engine. One blade of the two-blade wooden propeller was missing, as was a portion of the spinner. Cockpit examination revealed the magneto switches were off but the master switch was still on and a whirling noise could be heard. Fire department personnel disconnected the battery and the noise stopped. The throttle was full forward, the propeller control was in a midrange position, and the mixture control was full rich. Witnesses made no mention of strobe lights or landings lights iulluminated.

N103LM was examined in the tie down area of The Cloud Base, a glider flight school, rental agency, and operator of N103LM. Approximately 18 inches of the right wing, just outboard of the aileron, had been sheared off. A black rubber smear was noted on the top of the right wing about 8 feet inboard from the wing tip. The glider is not equipped with an electrical system and had no position, strobe, or landings lights.

Medical and pathological information

Autopsies (96A-66 and 96A-67) on the pilot and student pilot-rated passenger in N194JP were performed by Dr. William W. Howland of the Boulder County Coroner's Office. The pilot's death was attributed to multiple internal injuries. The student pilot-rated passenger's death was attributed to drowning. A toxicological screen was performed by FAA's Civil Aeromedical Institute in Oklahoma City, Oklahoma. No carboxyhemoglobin, cyanide, ethanol, or drugs were detected.

The pilot of N103LM voluntarily submitted to toxicological testing. Conducted by ChemaTox Laboratory, Inc., of Boulder, Colorado, no drugs or alcohol were detected.

Additional information

The wreckage of N194JP was released to the owner's representative on June 29, 1996. N103LM was released to the owner on June 29, 1996.

Aircraft · 2

Registration
N194JP
Reported as
Prevatt RV-6
Category
Airplane, amateur-built
Serial number
21752
Airframe hours
90
Engine
Lycoming O-320-A2A, 150 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Registered owner
David R. Prevatt
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · January 1, 1996 · 17 hours before
Departed
2V2 · Longmont, CO
Destination
APA · Englewood, CO
Airport
1V5 · Boulder Municipal

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.

Registration
N103LM
Reported as
Burkhart Grob G103C Twin III Acro (G103C TWIN)
Category
Glider
Serial number
34107
Airframe hours
2,893
Engine
unknown
Damage
Minor damage
Flight
Personal · Part 91
Registered owner
Bruce A. Miller
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · April 30, 1996 · 83 hours before
Departed
1V5
Airport
1V5 · Boulder Municipal, runway 8R, 4,100 × 75 ft, asphalt

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot, aircraft N194JP
Age
49
Certificate
Private
Airplane ratings
Single-engine land
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Toxicology
Performed
Flight hours
318 total · 88 in this make and model · 294 as pilot in command · 9 in the last 90 days · 5 in the last 30 days · 2 in the last 24 hours
Role
Pilot, aircraft N103LM
Age
35
Certificates
Flight engineer, Commercial, Airline transport, Flight instructor
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane, Helicopter
Medical
Expired
Seat
Rear
Toxicology
Performed
Flight hours
6,698 total · 60 in this make and model · 6,532 as pilot in command · 75 in the last 90 days · 23 in the last 30 days · 4 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
80° at 14 knots
Visibility
60 statute miles
Lowest ceiling
20,000 ft broken
Temperature
81 °F, dew point 43 °F
Altimeter
30.00 inHg
Observed at
BJC, 12 nm away

FAA reports on this event · 2

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.