Steve Fossett Disappearance
It was the 3rd of September in 2007 at around 09:30 local time in California when a Bellanca 8KCAB-180 (Super Decathlon) registration N240R disappeared in the ‘Nevada Triangle’.
The 63-year-old pilot was Steve Fossett, a famous aviator and sailor. He is still the holder of multiple world records, including the fastest east-to-west transcontinental record for non-supersonic fixed-wing aircraft, flying from Jacksonville, Florida to San Diego, California in 3½ hours. He was also the first solo pilot to achieve a nonstop (un-refuelled) flight around the world in an aircraft. He departed Kansas on the 28th of February 2005 and returned to his airfield on 3rd of March after sixty-seven hours of flight. This flight is still the record holder for fastest circumnaviation of the world, nonstop and non-refuelled, with an average speed of 550 km/h (340 mph) in the Virgin Atlantic GlobalFlyer.
Fossett held an airline transport pilot certificate (ATPC) with more privileges and ratings than I can be bothered to list. Actually when I looked up his records, I was slightly surprised to see that he had a total of only 6,731 hours flight time. It’s not a trivial amount, by anyone’s count, but I presumed that someone working as a test pilot and record setter would have more, somehow.
Anyway, suffice it to say his paperwork was in order and his experience was good. However, he had only forty hours flight time in the aircraft that he was flying that day.
The Bellanca 8KCAB-180 ‘Super Decathlon’ is a single-engine high-wing fixed landing gear aircraft. The two-seater plane made from wood and fabric is popular for training and aerobatics. This specific Super Decathlon, registration N240R, was nearly 30 years old. It had passed its annual inspection in April 2007. Six weeks later, the Super Decathlon ran off the runway during its landing roll, crashing into a barbed wire fence. The propeller was replaced and the aircraft was returned to service on the 29th of June. At that time, it had 1,094.7 hours and the chief pilot said that the aircraft flew 10 to 12 hours after being returned to service.
The Super Decathlon was kept at the Flying M Ranch, a private strip located near Smith Valley, Nevada. The Flying M Club is at the centre of a million-acre estate and one of the most sought-after takeoff spots in the US; the club’s fans have included Buzz Aldrin, Morgan Freeman, Sylvester Stallone and John Denver. It’s known as a base for wealthy amateur pilots. The area is famous for the strong desert thermals which allow for gliders to circle for hours.
On the 1st of September, two days before the flight, the chief pilot and another pilot put the Super Decathlon through its paces, performing extensive aerobatic manoeuvres without incident.
Morning dawned on the 3rd of September with clear blue skies, a wonderful day to go flying. Fossett and the chief pilot had breakfast together and Fosset said that he wanted to fly the Super Decathlon that day. His wife described Fosset’s plan as a flight for pure pleasure, “a Sunday drive”.
The chief pilot went to the hangar to confirm that the Super Decathlon was full of fuel and ready for flight. Fossett arrived at quarter past eight and ran through his pre-flight checks.
After he finished, the chief pilot took a moment to review with him the starting procedures of the fuel-injected engine and asked Fosset where he was going that day. Fossett told him that he planned to head south to Highway 395, which runs north/south along the eastern side of the Sierra Nevada mountains. He did not wear a parachute and did not mention any intention to perform aerobatics. He took the front seat of the tandem two-seater aircraft.
The chief pilot expected Fossett to be gone for two hours or so and he got on with other things. Another ranch employee remembered looking up and seeing the aircraft flying around nine miles south of the airstrip. He immediately recognised the Super Decathlon, as it was used for spotting cattle which he rounded up on the ground. He saw it flying around 150-200 feet above the ground, heading south.
This was the last verified sighting of Fossett in the Super Decathlon.
Fossett’s personal pilot arrived at 11:00 to assist with parking the plane (I have to admit to a twinge of jealousy here – I would love someone to come and park my aircraft for me!) but Fossett still hadn’t returned. By 11:30, the chief pilot became concerned. The aircraft had an endurance of four to five hours and Fossett had only mentioned a short flight.
Within half an hour, he had organised an aerial search. The Super Decathlon had an Emergency Locator Transmitter (ELT) but no transmissions were picked up and there were no records of emergency radio transmissions.
Meanwhile, it was clear that the Super Decathlon could not possible still be flying.
Soon, an extensive search was underway, including the Civil Air Patrol, State and County authorities and friends of the pilot. Between them, they searched terrain across several counties and crossing the state line. The search involved 629 flights of 1,774 flying hours to cover 22,000 square miles (57,000 km²) of rugged terrain in difficult flying conditions. High winds caused the operations to be suspended at midday on day two and the winds continued to pose difficulties throughout the search.
A possible witness was found. A camper at East Lake reported that he’d seen an aircraft in the area which might have been the Super Decathlon. He was camped at an elevation of 9,400 feet, where the peaks in the area reached 12,000 feet. It was a little before 10:00 when he saw the aircraft flying from north to south, heading towards Yosemite. He pointed out the plane to the other people who they were camping with, as the aircraft was heading into the wind and it looked almost like it was standing still. He believed that the aircraft was at about 11,500 feet.
However, the searchers found no trace of missing aircraft and pilot and as the days went past, they knew the chances for his survival were dwindling.
Four days after the disappearance, high-resolution satellite imagery was made available on the Amazon Mechanical Turk website in hopes that the public could flag potential areas of interest for the searchers. Some 50,000 people took part in the crowd-sourced search, poring over 300,000 detailed photographs each covering 278 square feet (25 m²) of terrain.
However, the online search did not flag any areas of interest. The Civil Air Patrol was flooded with emails and phone calls from people convinced they had seen something, including many sightings of intact aircraft, which turned out to be search aircraft scouring the area. CAP’s Public Affairs representative said it was more of a hindrance than a help. She told Wired magazine at the time that, “The crowdsourcing thing added a level of complexity that we didn’t need, because 99.9999 percent of the people who were doing it didn’t have the faintest idea what they’re looking for.”
By the 12th of September, the searchers knew that Fossett was unlikely to still be alive. By the 17th, the Civil Air Patrol suspended their search flights, although National Guard and private search flights continued. By the 2nd of October, the search operation was called off. It had been the largest and most complex peacetime search for an individual in US history but it had failed.
Eight previously uncharted crash sites were reported over those weeks but, as they were hoping to rescue Fossett if he had survived the crash, the searchers took only enough time to verify that the wrecks could not be the Super Decathlon before moving on.
It was a year later almost to the day, when finally a breakthrough occurred. A hiker in the Sierra Nevada Mountains contacted the Madera County Sheriff’s Department to say that he’d found some personal effects, including an identification card and a pilot certificate, near Minaret Summit. Both documents belonged to Steve Fossett.
Travelling to the location described by the hiker, they discovered more effects: a pair of tennis shoes, credit cards, and Fossett’s drivers license along with skeletal fragments. About half a mile from there, they finally found the crash site. The peaks of that area rose to 13,000 feet and more. The location was about 30 miles south of the East Lake campsite where the campers had seen a plane flying against the wind. The Civil Air Patrol confirmed that they’d searched the area once by air, however they had seen nothing to make them aware that the aircraft was there.
Once there, they discovered a boulder at 10,000 feet with paint transfers on it from the belly of the aircraft and the left main wheel. Pieces of wreckage was scattered uphill among the charred plants and scorched earth. Looking uphill about two hundred feet from the boulder, they found the burnt remains of the steel tubing frame of the fuselage. The wings were broken, the fabric burned away.
The door was still attached to the doorframe with the emergency release handle still locked. The front seat, where Fossett had been sitting, was crushed to about 1/3 of its original dimensions. All of the instruments were destroyed, as was the Emergency Locator Transmittter.
The nearby pine trees needles had turned dark from fire. The battered engine lay another one hundred feet uphill from there with the propeller blades broken off.
Small bone fragments at the accident site were collected but it wasn’t possible to tell if they were human remains. The skeletal fragments found near the paperwork were confirmed by DNA to be the remains of Steve Fossett. The cause of death was given as multiple traumatic injuries.
Once they found the aircraft, they were able to isolate the radar tracks from that day in order to follow the route that the Super Decathlon took. It was a southbound track which had been spotted on radar from the start.
According to the radar returns, at 09:07 there was a target flying southbound, following the crest of the Sierra Nevada Mountains, about 35 miles south-southwest of the Flying M Ranch Airport. The track of the target followed Highway 395 and then disappeared at 09:27 about one mile northwest of the accident site.
When Fossett had disappeared, this radar track had been eliminated as the timestamp did not agree with the Flying M employee who said he’d observed the aircraft 9 miles to the south of the airstrip. He’d said that he’d seen the aircraft between 09:25-09:35 and remembered the time because he’d been on a phone call when he saw it. This siting meant that the target appearing on radar at 09:07 couldn’t possibly have been Fossett. As they desperately needed to reduce the search area, they dismissed this and many other radar returns as irrelevant.
The Flying M employee had seen and correctly identified the aircraft. But when investigators checked the telephone company’s time log, the phone conversation was shown to be an hour earlier and thus the correct time of this last confirmed sight of Fossett’s aircraft was an hour earlier at 08:25-08:35.
Initially, the radar track showed that the transponder of the target was reporting altitudes of 14,500-14,900 feet. After the first few minutes, no altitude information was received.
The wreckage of the aircraft showed that the Super Decathlon was at 10,000 feet and heading north at the time of impact. This means that the Super Decathlon had turned 180° after radar contact was lost.
The transponder altitude shows the pressure altitude, which means that it is unaffected by your setting the local pressure. ATC then adjust the reading for the local altimeter setting but, in the case of the radar return, that is the raw data as sent by the transponder. So to understand the actual altitude of the aircraft, we need to look at the weather that day.
Mammoth Yosemite Airport is about fifteen nautical miles from the crash site, at an elevation of 7,129 feet. On the day of the crash, the 3rd of September, the density altitude at the airport at 10:49 was 9,700 feet. That is to say, the difference between the pressure altitude at the airport was over 2,500 feet.
Density altitude is pressure altitude corrected for nonstandard temperature. As temperature and altitude increase, air density decreases. In a sense, it’s the altitude at which the airplane “feels” its flying.
On a hot and humid day, the aircraft will accelerate more slowly down the runway, will need to move faster to attain the same lift, and will climb more slowly. The less dense the air, the less lift, the more lackluster the climb, and the longer the distance needed for takeoff and landing. Fewer air molecules in a given volume of air also result in reduced propeller efficiency and therefore reduced net thrust. All of these factors can lead to an accident if the poor performance has not been anticipated.
This means that the aircraft would have been slower to climb than expected. The Super Decathlon’s maximum rate of climb at a pressure altitude of 12,000 feet was 370 feet per minute. At 13,000 feet, its maximum rate of climb was 300 feet per minute.
That in itself would catch out an inexperienced pilot; however, Fossett knew the area and shouldn’t have been taken unawares, even with the increased density altitude that day.
A meteorologist did a simulation of the conditions that day based on the Advanced Research Weather Research and Forecasting numberical model. His simulations showed downdrafts in the accident area of 300 feet per minute and in one case, as high as 400 feet per minute. The meteorologist believes that these were underestimated, as the simulation didn’t fully take into account the steep terrain slopes.
Visual meteorological conditions existed in the accident area at the time of the accident. Mean winds at 10,000 feet were from 220 degrees at 15 to 20 knots; some gusts of 25 to 30 knots may have occurred. Moderate turbulence and downdrafts of at least 400 feet per minute probably occurred at the time and in the area of the accident. The magnitude of the downdrafts likely exceeded the climb capability of the airplane, which, at a density altitude of 13,000 feet, was about 300 feet per minute.
The Super Decathlon was unlikely to be able to keep altitude, let alone climb over the mountain range. However, the downdrafts wouldn’t have really come into their own until he came closer to the rising terrain. By the time that Fossett realised he was in trouble, it was too late.
Here’s the NTSB conclusion:
Examination of the accident site revealed that the airplane was on a northerly heading at impact, indicating that the pilot had executed a 180-degree turn after radar contact was lost. Ground scars and distribution of the heavily fragmented wreckage indicated that the airplane was traveling at a high speed when it impacted in a right wing low, near level pitch attitude. A postimpact fire consumed the fuselage, with the exception of its steel frame. The wings were fragmented into numerous pieces. The ELT was destroyed. Damage signatures on the propeller blades and the engine crankshaft indicated that the engine was operating at impact. Examination of the airframe and engine revealed no evidence of any malfunctions or failures that would have prevented normal operation. Visual meteorological conditions existed in the accident area at the time of the accident. Mean winds at 10,000 feet were from 220 degrees at 15 to 20 knots; some gusts of 25 to 30 knots may have occurred. Moderate turbulence and downdrafts of at least 400 feet per minute probably occurred at the time and in the area of the accident. The magnitude of the downdrafts likely exceeded the climb capability of the airplane, which, at a density altitude of 13,000 feet, was about 300 feet per minute.
The National Transportation Safety Board determines the probable cause(s) of this accident to be: The pilot’s inadvertent encounter with downdrafts that exceeded the climb capability of the airplane. Contributing to the accident were the downdrafts, high density altitude, and mountainous terrain.
There’s a few open questions on this but I’ve gone on long enough, so I will address them in the next post. It’s not finished yet and I have almost 7,000 words worth of notes, so if you have specific issues that you’d like more information on, please feel free to leave a comment and I’ll add what I know, if I know.
EDIT: The follow-up post is now here.