FTW98FA145

NTSB accident investigation · Duci'S Vans RV-3 · Elbert, CO · March 8, 1998

Accident · FatalField investigationFinal report
Date
March 8, 1998, 15:10 local (22:10 UTC)
Place
Elbert, CO
Injuries
1 fatal
Damage
Destroyed
Phase of flight
Maneuvering
Aircraft
N99HVDuci'S Vans RV-3
Weather
Visual (VMC) · Day
Status
Completed · report December 31, 1998
Report
Approved by Office Director
FAA report
19980308002819A
Case key
20405

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

in-flight failure of the right wing spar (for an undetermined reason) as the pilot was performing aerobatic flight. The airplane's excessive gross weight (for aerobatics) was a related factor.

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.

Airframe/component/system failure/malfunctionManeuvering
Aerobatics - initiatedPilot in commandCause
Aircraft weight and balance - excessivePilot in commandFactor
Wing,spar - failure,totalCause
Wing - separation
In flight collision with terrain/waterDescent - uncontrolled

Analysis

A witness said the pilot was performing aerobatics, and while maneuvering, the aircraft (acft) went into a nose high attitude as if it was coming to the top of a loop. He said one of the wings suddenly 'folded' up, and 'It looked as if it had bent at the connection between the wing and the fuselage. . . .' The acft then entered an uncontrolled descent & crashed. Metallurgical exam of the right wing revealed overload fractures in the lower & upper main spar caps, which were indicative of upward failure; initial fracture was in the lower cap area. Twisting & upward bending of the main upper spar cap was noted, as well as 'overstress separation.' Five bolt holes were found at the inboard portion of the upper & lower main spar caps with no respective bolts or remnants of such bolts. No deformation or distortion of any of the bolt holes was noted, but circular markings were noted on the forward side of both outboard holes, & similar indications were noted on the aft side of 2 other holes in the lower main spar cap. The investigation did not determine whether the missing bolts had failed & separated during the breakup, or if they had not been reinstalled during previous maintenance/modification. All rivets in both the upper & lower main spar caps were broken through the shanks 'consistent with direct shear separations. No evidence of cracking or breaking of rivet heads . . . was noted.' This was 1 of 3 RV-3s built by Tony Duci & the 2nd to structurally fail in flight. Acft had been modified as an RV-3A, but had not been re-certified as such. Aerobatic gross weight limit (1,050 lbs) had been exceeded by an estimated 120 lbs.

Factual narrative

History of flight

On March 8, 1998, approximately 1510 mountain standard time, a Duci's Vans RV-3 (upgraded to an RV-3A), N99HV, was destroyed when it collided with terrain while maneuvering near Elbert, Colorado. The airline transport rated pilot, the sole occupant aboard, was fatally injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the local personal flight conducted under Title 14 CFR Part 91. The flight originated at Elbert approximately 1445.

The only witness to the accident, a U.S. Air Force Academy cadet, was watching the airplane from the south end of Kelly Airpark. The pilot "was performing aerobatics (loops, chandelles, rolls)." He then saw the airplane in a nose high attitude, "as if he were coming to the top of a loop." He said "one of his wings suddenly 'folded' up. It looked as if it had bent at the connection between the wing and the fuselage. It did not separate from the fuselage." The witness said the airplane nosed over, entered a "gentle spin," then stabilized and increased speed as it dove towards the ground. The witness estimated the time of the accident to be 1510, and he went to the nearest telephone and called 9-1-1. According to the Elbert County Sheriff's Office, the call was received at 1511.

Two other witnesses submitted written statements, saying they had seen an airplane performing aerobatics over their homes. One witness said the airplane was 100 feet above the ground; the other said it was 65 feet. Their description of the airplane was similar to that of N99HV.

The accident occurred during the hours of daylight at a location of 39 degrees, 13.732 minutes north latitude, and 104 degrees, 37.004 minutes west longitude. The wreckage was in a field in the rear of 2782 County Road 98, at an elevation of 6,939 feet msl.

Crew information

The pilot, Christopher Keith Coffland, age 35, was born on January 7, 1963. He attended the United States Air Force Academy from August 1981 to June 1985, and was commissioned. He held Airline Transport Pilot Certificate No. 358625748, dated March 19, 1995, for multiengine land airplanes, with commercial privileges in single engine land airplanes and gliders (aero tow only). He also held a Flight Instructor Rating, dated February 9, 1996, for single and multiengine airplanes and instruments, and a Ground Instructor Rating, dated September 26, 1994, for advanced and instrument instruction. His first class airman medical certificate, dated June 23, 1997, contained no restrictions or limitations.

Three master logbooks and eight smaller pilot logbooks were submitted for examination. It was discovered that the flight times contained in seven of the smaller logbooks (and part of the eighth) had been transferred to the three master logbooks. These master logbooks contained entries from May 22, 1984, to May 24, 1989; May 25, 1989, to July 23, 1993; July 24, 1993, to November 29, 1997, respectively. The eighth logbook contained RV-3 entries exclusively from June 2, 1997, to February 12, 1998. A summary of flight time contained in the three master and RV-3 logbooks, and a summary of flight time by aircraft type are attached to this report. Only one aerobatic entry was found in the RV-3 logbook. On June 13, 1997, the pilot flew the airplane for 0.6 hours and recorded the following: "Local-aerobatic-loop, slideback, split S, barrel roll, aileron roll."

Aircraft information

N99HV (formerly N67TD), s/n RV3-528, was one of three RV-3s built by Tony Duci (deceased). Construction was completed on November 11, 1979, and the airplane was issued an FAA Special Airworthiness Certificate in the Experimental Category on January 29, 1980. It was equipped with a Lycoming O-320 engine (s/n L-8663-27), rated at 150 horsepower, and an all wood, 2 blade, Great American propeller (m/n 68-66). The first RV-3 Mr. Duci constructed, N55F (formerly N55TD), broke up in flight on March 11, 1981, near Kennett, Missouri (see NTSB accident report MKC 81-F-A025). The accident airplane was his second creation. The third RV-3 he built, N81TD, was found to be registered to a private individual in Mullins, South Carolina.

The following entry was made in the airplane's Performance Data: "11/20/81 - Delivered to Morgan, Mojave. 5/13/82 - Picked up plane with mods C-1 and new propeller." The following entry, dated May 13, 1982, was made in the airplane's Repairs Log: "Morgan Aviation - Completed modification CN-1. Copy appended this manual. This completes structural details - spar attachments - to qualify model change to RV-3A. To complete this qualification for acrobatics, flight demonstration remains as specified in CN-1."

Upon learning of the accident, the airplane's previous owner, Henry Van Noy, submitted the following statement, dated March 12, 1998: "Mr. Coffland. . .received a placard and letters regarding the limit on acrobatics and the available main beam retrofit which had been reserved at the factory for his airplane. He said that he had discussed this with the staff at Van's Aircraft and did not plan to do acrobatics, and thus would defer the modification."

Mr. Coffland's mechanic, John P. Sanders, submitted a statement, dated March 11, 1998, to wit: "I had no knowledge of any modification that was available to beef-up the spars on the RV-3. . .Chris (Coffland) never mentioned anything about a spar weakness or any concern about failure of his aircraft."

In a note to Van's Aircraft, Inc., dated June 13, 1997, Mr. Coffland wrote: "Request that rights to the CN-2-I spar alteration kit be transferred to me and shipped as per request form." Van's Aircraft Invoice 116733 indicated "CN-301 CN2-I Spar Change" was shipped to Mr. Coffland on June 19, 1997.

According to the maintenance records, the airplane was last inspected on March 1, 1998, "in accordance with the scope and detail of Appendix D of Part 43 and found to be in a condition for safe operation." At that time, the airframe had accumulated 755.1 hours. In the engine logbook, errors were noted in the interchangeable use of total, Hobbs meter, and tachometer times. Correcting for these errors, it was determined that the engine had accumulated 2,209:72 total hours, and 1,086.4 hours since major overhaul.

Wreckage and impact information

The on scene examination disclosed a 15 foot long ground scar aligned on a magnetic heading of 268 degrees, terminating in a crater. From this point wreckage was distributed along a path aligned on a magnetic heading 230 degrees. The engine and propeller hub were 30 feet from the crater and slightly to the right of the wreckage path. The left wing and cockpit separated from the fuselage and were found 66 feet from the crater. The empennage and right wing were 164 feet and 196 feet beyond the crater, respectively.

There were three creases across the top of the right wing, and the wing was bent up. The wing had pulled out from the spar, leaving about 6 inches of spar stub still attached to the wing. The majority of the spar remained with the left wing, and was also bent up and curled.

Mr. Richard VanGrunsven, designer of the RV-3, examined the wreckage on March 16, 1998, and confirmed that the airplane had been modified and upgraded to an RV-3A in accordance with Change Notice CN-1. He also noted that some of the bolt holes in the spar immediately adjacent to (outboard) of the root rib showed little evidence (no elongation of the holes) of bolts having been installed. No bolt remnants were recovered and no torque marks were discernible (removal of bolts and nuts from the left wing revealed torque marks of the spar).

Medical and pathological information

An autopsy (#98A-093) and toxicological screen were performed by the El Paso County Coroner's Office County, Dr. David R. Bowerman, prosector. A toxicological screen was also performed by FAA's Civil Aeromedical Institute (CAMI). Both toxicology

Aircraft

Registration
N99HV
Reported as
Duci'S Vans RV-3
Category
Airplane, amateur-built
Serial number
528
Airframe hours
755
Engine
Lycoming O-320, 150 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Registered owner
Christopher K. Coffland
Airworthiness certificate
Special, Experimental (Special)
Last inspection
Annual · March 1, 1998 · 1 hours before
Departed
CO15 · 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
35
Certificates
Commercial, Airline transport
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--no waivers/lim.
Seat
Center
Toxicology
Performed
Flight hours
5,166 total · 22 in this make and model · 4,018 as pilot in command · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
30° at 5 knots
Visibility
50 statute miles
Lowest ceiling
None
Temperature
28 °F, dew point 5 °F
Altimeter
30.00 inHg
Observed at
APA, 29 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.