DEN05FA038

The pilot's father had just purchased the airplane for his daughter, and she was receiving model-specific training from a contract flight instructor. Her former flight instructor was aboard as a passenger. The engines were started and they quit. They were restarted and they quit again. They were started a third time, and the airplane was taxied for takeoff. Shortly after starting the takeoff roll, the pilot reported an unspecified engine problem. The airplane drifted across the median and parallel runway, then rolled abruptly to the right, struck the ground, and cartwheeled. The landing gear was down. Neither propeller was feathered. Disassembly of the right engine and turbocharger revealed no anomalies. Disassembly and examination of the left engine and turbocharger revealed the mixture shaft and throttle valve in the throttle and fuel control assembly were jammed in the idle cutoff and idle rpm positions, respectively. Manifold valve and fuel injector line flow tests produced higher-than-normal pressures, indicative of a flow restriction. Disassembly of the manifold valve revealed the needle valve in the plunger assembly was stuck in the full open position, collapsing the needle valve spring. A scribe was used to free the needle valve, and the manifold valve and fuel injector lines were again flow tested. The result was a lower pressure. Plunger disassembly revealed the threads had been tapped inside the retainer and metal shavings were found between the retainer and spring. The Teledyne Continental Motor (TCM) retainer has no threads. GPS download showed that 2,698 feet had been covered between the start of the takeoff roll and the attainment of rotation speed. Maximum speed attained was 132 mph. Computations indicated distance to clear a 50-foot obstacle was 2,000 feet, distance to clear a 50-foot obstacle (single engine) was 2,600 feet, and accelerate-stop distance was 3,000 feet.

History of flight

On December 17, 2004, at 1522 mountain standard time, a Cessna 421, N421FR, registered to and piloted by a commercial pilot, was destroyed when it impacted terrain 0.5-mile south-southwest of Centennial Airport (APA), Englewood, Colorado. Visual meteorological conditions prevailed at the time of the accident. The instructional flight was being conducted under the provisions of Title 14 CFR Part 91 without a flight plan. The pilot, flight instructor, and pilot certificated-passenger were fatally injured. The flight was originating at the time of the accident, and was en route to the Fort Collins-Loveland Airport (FNL), Fort Collins, CO.

The airplane arrived at Centennial Airport between 1330 and 1400, and the three occupants had lunch at the airport restaurant. The airplane was not refueled. According to a Denver Jet Center East employee, approximately 1500 a "pretty" female boarded the airplane and sat in the left seat. She was followed by "two older gentlemen, the one wearing a baseball cap, [who] sat in the right seat." She said that after both engines were started, the right engine quit, followed by the left engine. Her first impression was that the pilot had retarded the mixture handles. After some effort, the engines were restarted, but they quit one after another shortly thereafter. "It took many cranks to get them going again," she said. "They messed with the engines for at least 10 minutes." As the airplane taxied out for takeoff, she noticed a puff of black smoke but she could not be sure "which engine it was coming from."

According to the pilot's father, his daughter called him from the airport and told him they were having "engine problems" or "fuel problems," and that something had been "hooked up backwards." She asked that he notify the repair facility that they were returning the airplane for repairs. That was the last contact he had with his daughter.

The airplane was cleared for takeoff on runway 17L at 1521:41. At 1522:30 a female reported, "centennial tower four two one foxtrot romeo we're having engine trouble just to let you know." (See Transcript of Radio Communications, EXHIBITS). At 1522:43, there was a garbled transmission from the pilot. The airplane was seen to drift right across the median and runway 17R, then roll abruptly to the right and descend in a steep nose-low attitude. The airplane struck the ground, cartwheeled, and came to rest 1,017 feet southwest of the departure end of runway 17R (251º magnetic).

There were numerous witnesses to the accident (see EXHIBITS). One (witness #1) of two linemen working outside the Signature Flight Support facility, located near the intersection of runways 17L and 11, said that as the airplane passed his position, it did not appear to be climbing. "The aircraft appeared to be using right rudder as the nose of the aircraft had yawed to the right." His co-worker (witness #2) agreed that there was "full right rudder deflection." He then observed the airplane bank right "at a rapid rate . . . very steep bank angle . . . 90 degrees or more . . . [It] began to sink very fast . . . The aircraft hit the ground without changing its bank angle." Another employee (witness #3) inside the building said the airplane was crabbing "significantly to the right . . . The left wing would dip (in the down position) and the pilot would recover. This action continued 3 or 4 more times . . . The aircraft did not seem to gain or lose altitude . . . The aircraft's landing gear was extended."

Another witness (#4) who was driving home saw the airplane bank to the right and slowly descend. "I noticed the gear were still in transit mode coming up slow." He did not hear any unusual engine sounds, or notice any smoke or windmilling propellers.

Two flight instructors observed the accident. One instructor (witness #5) was on landing approach. He said the airplane "appeared to be aligned with its axis along the runway (17L) centerline, and about the same altitude as I was (250 feet agl) . . . It began to drift slowly to the right. The axis always was parallel to the departure runway, with wings level, no turn was initiated. The plane continued to drift over the grass between runways 17L and 17R, with no apparent climb or descent . . . Rather suddenly, the left wing rose, and in a continuing descending arc to the right, the aircraft made ground impact, followed by a cartwheel." The other instructor (witness #6) was departing on the downwind leg. He said the airplane "flying very slowly and pointed in a southwesterly direction. The left wing came up and the airplane did what appeared to be a Vmc roll."

The accident occurred during the hours of daylight at a location of 39 degrees, 33.367' north latitude, and 104 degrees, 51.249' west longitude. The accident site was at a GPS (Global Positioning System) elevation of 5,916 feet msl.

Personnel (crew) information

First Pilot

The first pilot held an airline transport pilot certificate with an airplane multiengine land rating, and commercial privileges in airplanes single-engine land, dated October 8, 1986. He also held a flight instructor certificate with airplane single/multiengine and instrument ratings, dated May 30, 2003, and a ground instructor certificate with an advanced rating, dated January 14, 1987. His second class airman medical certificate, dated May 6, 2004, contained the restriction, "Must wear corrective lenses." He was the owner and chief executive officer of Aircraft Training Resources. According to his most recent application for medical certification, he estimated he had logged the following flight time (in hours):

Total Time: 11,000

Last 6 Months: 250

Two pages of the pilot's logbook (which was kept on a computer, were provided by his daughter. The first page contained entries from March 31, 2003, to December 5, 2003, and the second page contained entries from January 1, 2004, to July 26, 2004, to wit (in hours):

Total Time: 222.7 197.5

Single-engine: 5.4

Multiengine: 217.3 197.5

Turboprop: 66.4 143.7

Night: 11.2 13.8

Actual Instruments: 20.9 18.3

Simulated Instruments: 0.5 87.5

Solo: 1.2

Pilot-in-Command: 224.7 197.5

Instruction Received: 1.5

Instruction Given: 205.8 187.7

Cessna 421: 74.7 5.5

According to his sister, the pilot's resume, updated in November 2004, showed the following flight time (in hours):

Total Time: 12,000

Multiengine: 7,850

Turboprop: 4,900

Total Instruments: 2,120

Pilot-in-Command: 11,700

Instruction Given: 3,500

His last biennial flight review, 1.5 hours duration, was dated May 30, 2003, and was taken in a Cessna 172.

Second Pilot

The second pilot, age 20, was a student at Metropolitan State College of Denver, majoring in aviation technology, and aspired to become an airline pilot. She held a commercial pilot license with airplane single/multiengine land and instrument ratings, dated July 12, 2004. Her third class airman medical certificate, date January 2, 2003, contained no restrictions or limitations. According to her logbook, containing entries from November 14, 2002, to December 4, 2004, she had accrued the following flight time (in hours):

Total Time: 414.6

Single-engine: 180.8

Multiengine: 247.1

Pilot-in-Command: 303.3

Instruction Received: 212.0

Night: 32.1

Actual Instruments: 8.7

Simulated Instruments: 53.5

Simulator: 14.0

Cessna 421: 31.9

Her commercial single/multiengine practical tests, taken in a Cessna 182 and a Piper PA-23-250 on July 12, 2004, respectively, constituted her biennial flight review.

Third Pilot

The third pilot held a commercial pilot certificate with airplane single/multiengine land and instrument ratings, dated February 15, 1974. He also held a flight instructor certificate with airplane single/multiengine land and instrument ratings, dated December 8, 2002. He was the second pilot's former flight instructor. His second clas