FTW97LA009

NTSB accident investigation · Young Cozy MK IV · Pueblo, CO · October 4, 1996

Accident · Serious injuriesLimited investigationFinal report
Date
October 4, 1996, 17:30 local (23:30 UTC)
Place
Pueblo, CO
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N96PJYoung Cozy MK IV
Weather
Visual (VMC) · Day
Status
Completed · report August 21, 1997
Report
Approved by Office Director
FAA report
19961004031119A
Case key
20085

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

the pilot/builder's improper design change which resulted in a loss of control following an intentional stall. A factor was an erroneous weight-and-balance calculation.

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.

Loss of control - in flightManeuvering
Stall - intentionalPilot in command
Aircraft weight and balance - inaccuratePilot in commandFactor
Maintenance,design change - improperPilot in commandCause
In flight collision with terrain/waterDescent - uncontrolled

Analysis

According to the pilot, he was practicing slow flight and stalls at 5,000 feet above ground level (10,000 feet msl). The only thing he could recall was that the 'main wing stalled' and that the canard was supposed to stall first. The nose pitched up, and he was unable to break the stall. After examining the wreckage, the airplane designer and an FAA airworthiness inspector concluded (1) the canard wing had too low an angle-of-incidence, (2) three of six vortilons had been removed from the main wing, (3) the pilot erroneously calculated the empty weight center of gravity (CG), making all other CG calculations incorrect, and (4) as fuel flowed towards the aft portion of the fuel tank during the stall, the CG moved 1.1 inches beyond the aft CG limit. The designer concluded that the aircraft had not been built according to the plans, but rather was 'converted' to an 'Aerocanard...an unauthorized, unapproved, rip-off design.' The pilot had about 400 hours of flight time in various Cozy aircraft, but he had accrued only about 17 hours in the Cozy MK IV.

Factual narrative

On October 4, 1996, approximately 1730 mountain daylight time, a Young Cozy MK IV, N96PJ, was substantially damaged when it collided with terrain at Pueblo, Colorado. The airline transport-rated pilot was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated at Pueblo, Colorado, on October 4, 1996, at 1704.

According to the pilot, he was practicing slow flight and stalls at 10,000 feet msl (5,000 feet agl). The only thing he could recall was that the "main wing stalled" and that the canard is supposed to stall first. The nose pitched up and he was unable to break the stall.

An examination of the wreckage at the pilot's Pueblo, Colorado, residence by an FAA airworthiness inspector, the airplane's designer, and an NTSB student intern on November 14, 1996, revealed the following: (1) Data supplied by the pilot on the elevator position he had to maintain in cruise flight indicates he used too low an angle of incidence on the canard wing. This would allow the airplane to attain too high an angle of attack. (2) Three of the 6 required vortilons (used to restrict spanwise air flow and prevent the main wing from stalling at high angles of attack) had been removed from the main wing. (3) Incorrect calculation of the airplane's empty weight center of gravity, resulting in the center of gravity being 0.1 inches beyond the aft limit. (4) Fuel flowing towards the aft portion of the fuel tanks during a climb to altitude and followed by an accelerated stall resulted in the center of gravity moving 1.1 inches beyond the aft limit.

The designer concluded that the aircraft had not been built according to the plans, but rather was "converted" to an "Aerocanard...an unauthorized, unapproved, rip-off design."

The aircraft was certificated in the experimental category.

The pilot had about 400 hours of flight time various Cozy aircraft; however, he had accrued only about 17 hours of flight time in the Cozy MK IV.

Aircraft

Registration
N96PJ
Reported as
Young Cozy MK IV
Category
Airplane, amateur-built
Serial number
203
Airframe hours
17
Engine
Lycoming O-360-A1G6D, 180 horsepower, reciprocating
Damage
Substantial damage
Flight
Part 91
Registered owner
Glenn P. Young
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · October 1, 1996 · 5 hours before
Departed
PUB · CO

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
47
Certificates
Airline transport, Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--no waivers/lim.
Seat
Left
Flight hours
9,350 total · 17 in this make and model · 7,980 as pilot in command · 55 in the last 90 days · 20 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
190° at 9 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
72 °F, dew point 45 °F
Altimeter
30.00 inHg
Observed at
PUB, 5 nm away

FAA reports on this event · 1

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

Other investigations on N96PJ · 1

Matched to the same aircraft by N-number and date.