DEN00FA175

History of flight

On September 17, 2000, at 1151 mountain daylight time, a Beech S35, N711HZ, registered to and operated by Hotel Zulu, LLC, was destroyed when it impacted terrain during an uncontrolled descent at Longmont, Colorado. The two airline transport certificated pilots were fatally injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated at Boulder, Colorado, approximately 1020, with an en route stop at Erie, Colorado.

N711HZ was later identified, by radar coverage from the Denver Air Route Traffic Control Center (ARTCC) in Longmont, Colorado, to have departed to the south from Erie Tri-County Airport, Erie, Colorado. The National Track and Analysis Program (NTAP), provided limited information pertaining to aircraft headings, approximate times, and approximate airspeeds. No altitude information was recorded. The NTAP revealed that at 1144, N711HZ flew south from Erie Tri-County Airport until 1146, when it turned to the right and headed northwest at 306 degrees. At 1148, N711HZ turned to the right again and headed north at 359 degrees until its last primary radar return at 1151. During the time from 1144 to 1151, N711HZ's average speed was 100 knots, with a maximum speed of 135 knots at 1147 and a minimum speed of 75 knots at 1150.

Three witnesses saw the airplane just prior to the actual impact. The witnesses were personally interviewed and each submitted written statements. The first witness, who was standing outside her front door west of Highway 287 and the accident site, wrote: "I [saw] a plane just north of my home headed eastward. It seemed not to be running at full power but not flying particularly low or performing any stunt maneuvers, as we are accustomed to in this geographical area. It continued eastward and veered slightly to the north, attempting a full throttle climb and appeared (from my visual perception) to flip into about a 180-degree bank, and perhaps may have been upside down...but due to the position of the sun I could not say for certain. Immediately after this action, the craft nosed straight downward narrowly missing a farmhouse and a number of out buildings. Upon impact there was an incredible explosion and an immediate fire following thereafter lasting only a couple of minutes. A huge cloud of black smoke continued to be visible thereafter for some time."

The second witness was driving south on Highway 287 when he noticed "an airplane flying at approximately 50-100 feet in the air. The plane was headed east and I would estimate it to be 500 yards east of Highway 287. The plane showed no apparent signs of trouble, other than flying so low. The plane suddenly made a sharp right turn to the south and turned upside down. The plane then nose-dived into the ground and exploded on impact."

The third witness was riding his bicycle on a dirt road paralleling an irrigation ditch just east of the accident site. He wrote, "...I was startled by the sound of an aircraft engine/prop which had suddenly increased in pitch and loudness. I looked up and saw a small airplane almost completely over on its back. The wings were almost parallel to the ground with the right wing of the airplane slightly higher than the left. I estimate the angle of the wings from horizontal to be 10 to 20 degrees. My direction of travel was towards the west, and the nose of the aircraft was pointed away from me in a northwesterly direction. From my position the aircraft appeared to be between 45 and 60 degrees from vertical and slightly north of me. The nose of the aircraft was initially pitching over. When it was pointed at the ground the aircraft stopped pitching and went into an almost vertical dive. The aircraft was oriented with the top of the airplane in a southeasterly direction. It appeared to be moving slowly when the dive started, maybe 20 to 30 mph... While it was pitching over I noticed the distinctive V-tail. After the airplane entered the dive, it did not change the direction of its forward motion until it was about 50 feet above the ground. At that time it appeared to start pulling out of the dive. However, the airplane was so close to the ground there was only a small change in its direction before it struck the ground...From the time I first saw the aircraft until it struck the ground there was no smoke or flames visible and the engine was running. The airplane appeared to be completely intact. The entire sequence of events took about 5 seconds..."

Occupants of two nearby houses said they heard a loud noise that shook their houses, and then heard an explosion. They then observed a fireball in the field. Other witnesses reported hearing the airplane pass overhead. One witness, a United Air Lines pilot who did not see the impact, reported hearing the engine make an unusual "popping" sound. Shortly thereafter, he saw smoke and drove to the scene. Another witness, standing in a field adjacent to the accident site, saw the airplane flying slow from south to north about 150 feet above the ground. Engine sounds stopped and the airplane disappeared from view behind a barn. He, too, heard the impact and saw smoke, and ran to the scene.

The accident occurred during the hours of daylight at a location of 40 degrees, 7.685' north latitude, and 105 degrees, 5.611' west longitude.

Personnel information

The left seat pilot held an airline transport pilot certificate, dated September 14, 1994, with an airplane multiengine land rating, type ratings in the Boeing 727, Boeing 757/767, and Learjet, and commercial privileges in airplanes single engine land. He also held a flight engineer certificate, dated December 5, 1969, with a turbojet rating. He also held a first class airman medical certificate, dated September 10, 1998, with no restrictions or limitations. At the time he made application for this medical certificate, he estimated he had accrued 18,200 total flight hours, 400 hours of which were accrued in the previous six months (see exhibits for more details of flight time). He was a retired American Airlines captain.

The right seat pilot held an airline transport pilot certificate, dated July 18, 1996, with an airplane multiengine rating, type ratings in the Boeing 737, Douglas DC-9, and Learjet, and commercial privileges in airplanes single engine land. He held a flight engineer certificate, dated May 5, 1972, with turbojet and turboprop ratings, and a flight instructor certificate, dated October 21, 1977, with an airplane single engine rating. He also held a first class airman medical certificate, dated May 1, 2000, with the restriction, "Must have available glasses for near vision." At the time he made application for this medical certificate, he estimated he had accrued 18,000 total flight hours, 700 hours of which were accrued in the previous six months (see exhibits for more details of flight time). He had been an Eastern Air Lines and a United Air Lines captain. After his 60th birthday, he continued to fly as a flight engineer with United Airlines, a position he held at the time of the accident.

The two pilots were brothers. The left seat pilot had 50.19 hours in the Beech S35. According to a Hotel Zulu, LLC, spokesman, the right seat pilot had never flown the airplane.

Aircraft information

N911HZ (s/n D-7699), a model S35, was manufactured by the Beech Aircraft Corporation in December 1964. It was equipped with a Teledyne Continental IO-520-BA(3) fuel injected engine (s/n 280688-R), rated at 285 horsepower, and a McCauley 2-blade, all metal, constant speed propeller (m/n 2A36C23-PCE).

According to the airplane maintenance records, the last annual inspection was performed on July 14, 2000, at a tachometer time of 1,422.36 hours and a total airframe time of 3,651.37 hours. The engine was factory rebuilt by Teledyne Continental Motors on February 28, 1991, and was installed on N911