- Parabolic Arc
- March 30, 2023
Shock, Tears & Spin: The Aftermath of the SpaceShipTwo Crash
Part 5 in a Series
In his autobiography, Chuck Yeager dismissed Tom Wolfe’s “right stuff” as a meaningless phrase for describing a pilot’s attributes. Good pilots are not born, they are made. Yeager attributed his success to a combination of natural abilities (good coordination, excellent eyesight, intuitive understanding of machinery, coolness under pressure) and good old-fashioned hard work. He worked his tail off learning how to fly, learned everything he could about the aircraft he flew, and spent more time flying them than anyone else.
Yeager also mentioned another factor: luck. He was born at the right time, and found himself in the right places to make a career out of flying. Unlike many of his contemporaries, he always managed to find his way out of tight spots through a combination of skill and luck.
“The secret to my success was that I somehow always managed to fly another day,” Yeager wrote. “To be remembered for accomplishing significant things, a test pilot has to survive. Hell, I could have busted my ass a dozen times over and nobody would have heard of me. I would have been Yeager Boulevard carrying military housewives to the commissary at Edwards.”
On the morning of Oct. 31, 2014, Mike Alsbury’s luck ran out in the sky near Koehn Lake. Piloting SpaceShipTwo in powered flight for the first time in 18 months, he made a mistake from which he could not recover. The ship broke up, and he plummeted to Earth still strapped into his seat.
His friend Pete Siebold was extremely lucky. He was thrown free of SpaceShipTwo as it disintegrated around him. When he regained consciousness in the thin air, he had the presence of mind to release himself from his seat so the parachute could deploy later. The chute was undamaged by the breakup and saved his life.
Siebold’s injuries were not life threatening, which was very fortunate given that it took emergency medical personnel about 45 minutes to reach him after the ship broke up. If his injuries had been more serious, he might have died beside a creosote bush in a desolate corner of the Mojave Desert. Instead, he spent three days in the hospital and lived to fly another day.
Siebold’s most serious injuries were in his right arm, which was fractured in four places. Doctors reset his arm in surgery over the weekend. They later discovered that his left little toe was fractured. The rest of Siebold’s body was banged up as a result of the ship’s breakup. He had a small gash in his right elbow as well as scrapes, bruises and contusions on his right wrist, right shoulder, chest and legs. Doctors told him the “clunking” noise in his right chest was likely torn muscle or cartilage between his ribs. Siebold also had continuing problems with his eyes.
“He was initially diagnosed with only corneal scratches in his eyes but he removed a piece of fiberglass from his left eye during his hospital stay,” according to a National Transportation Safety Board (NTSB) interview summary. “His eyes did not improve as fast as he was told they would so he saw an ophthalmologist after being discharged. The ophthalmologist also removed some foreign matter from his left eyelid and a ‘silver sliver’ from his right cornea. His eyes improved quickly almost immediately after the procedure.”
On Nov. 13, 2014, Mojave said goodbye to Alsbury at a memorial service held at the Lancaster JetHawks baseball stadium. It was an invitation-only event for Alsbury’s family, friends and co-workers. Virgin Galactic Founder Richard Branson flew in on his private jet to attend. At the end of the service, WhiteKnightTwo made a flyover of the stadium without the spacecraft it had carried aloft for its final flight two weeks earlier.
Later in the day, a smaller group of Alsbury’s family and friends gathered in an aircraft hangar in Tehachapi for a more intimate memorial service. They told stories about a man they knew as a good friend, co-worker, father and husband.
“Mike was an amazing man in so many ways,” his widow, Michelle Lynn Saling, wrote in a statement to the NTSB. “He was kind, generous, humble, intelligent and methodical. He was a loving and attentive father and husband. He loved spending time with family. He always made time for us and no matter what we were doing we had fun together.
“He constantly had a smile on his face and was positive and cheerful. He enjoyed being outdoors — hiking, fly fishing, camping, mountain bike riding. He was a reliable, dedicated employee and worked his hardest. He loved flying. He was always there to lend a helping hand and was a great teacher and friend to many. He had a way with being aware of people’s feelings and was very respectful. Mike loved life. He is so very special and was my best friend.”
For Scaled Composites, the loss of SpaceShipTwo brought an abrupt and tragic end to a program that had begun so optimistically 10 years earlier. After winning the Ansari X Prize in October 2004, founder Burt Rutan had stood on the Mojave tarmac and boldly promised to develop a successor vehicle that would be at least 100 times safer than any spacecraft that had ever flown. Branson promised to begin flying passengers in three years.
Despite a decade of work and hundreds of millions of dollars spent, SpaceShipTwo had never flown anywhere near space. The number of powered flights (four) now equaled the number of deaths in the program. Alsbury was not the first casualty of the SpaceShipTwo program. Three Scaled engineers had been killed in a horrific test stand explosion in 2007 during a nitrous oxide cold flow test. Before that tragic day, Scaled had never lost an employee.
Scaled Composites and Virgin Galactic had originally partnered in The Spaceship Company, a separate entity that would build the SpaceShipTwo and WhiteKnightTwo vehicles once the prototypes had been tested. However, Scaled had pulled out of the partnership years earlier. It would now be up to Virgin to build and test the second SpaceShipTwo.
Thus, Scaled’s involvement in the program ended not with the handover of SpaceShipTwo and the feeling of a job well done, but with yet another painful loss and a haunting question that no one would ever be able to answer.
The NTSB investigated the SpaceShipTwo accident for nine months, but it reached no definitive conclusion on why Alsbury unlocked the ship’s feather mechanism prematurely. However, the board did publish findings of fact that made it clear that the loss of SpaceShipTwo involved more than simple pilot error.
Finding: “The copilot was experiencing high workload as a result of recalling tasks from memory while performing under time pressure and with vibration and loads that he had not recently experienced, which increased the opportunity for errors.”
It had been 18 months since Alsbury had flown SpaceShipTwo in powered flight. Neither practicing in the simulator nor flying an Extra plane came close to replicating an ascent that another pilot called a catapult shot that didn’t quit. The pilots’ workloads were higher than experienced by space shuttle pilots. Alsbury and Siebold were not able to cross-check what each other were doing. Siebold didn’t know his co-pilot had unlocked the feather prematurely until he was told in the hospital.
The lack of recent experience can be tracked to SpaceShipTwo’s slow flight test program and its troubled hybrid engines. Months went by between powered flights with the rubber engine. There was then a 10-month gap between the third and fourth powered flights as engineers made modifications first for the enhanced rubber engine and then for the nylon motor.
It’s very difficult to develop any proficiency in a vehicle if you’re not flying it regularly. Especially one like SpaceShipTwo, which is essentially hand flown and lacks computers and automated systems to handle some of the workload. A flight test engineer might have eased some of the burden on the pilots, but there was none on board.
The high cost of flight tests – especially powered ones – also limited flight opportunities. SpaceShipTwo was not fully reusable; the engine casing and nozzle had to be replaced after every flight. This was expensive. Sources say Virgin Galactic was trying to complete the test program with as few flight tests as possible during a time when it was short on funds. The result was a plan for a handful of high-risk flights that would quickly expand SpaceShipTwo’s flight envelope.
The NTSB also faulted Scaled Composites for the way it designed the feather, analyzed the risks of it deploying prematurely, and trained its pilots.
Finding: Although Scaled Composites’ systems safety analysis (SSA) correctly identified that uncommanded feather operation would be catastrophic during the boost phase of flight and that multiple independent system failures had to occur to result in this hazard, the SSA process was inadequate because it resulted in an analysis that failed to (1) identify that a single human error could lead to unintended feather operation during the boost phase and (2) consider the need to more rigorously verify and validate the effectiveness of the planned mitigation measures.
Finding: By not considering human error as a potential cause of uncommanded feather extension on the SpaceShipTwo vehicle, Scaled Composites missed opportunities to identify the design and/or operational requirements that could have mitigated the consequences of human error during a high workload phase of flight.
Finding: Scaled Composites did not ensure that the accident pilots and other SpaceShipTwo test pilots adequately understood the risks of unlocking the feather early.
Finding: Human factors should be emphasized in the design, operational procedures, hazard analysis, and flight crew simulator training for a commercial space vehicle to reduce the possibility that human error during operations could lead to a catastrophic event.
The feather device was intended for deployment during re-entry; that’s what Scaled’s engineers focused on with a laser-like intensity. They didn’t sufficiently guard against an accident during powered ascent.
Scaled was not the first spacecraft builder to fall into that trap. In 1967, NASA lost three Apollo astronauts in a flash fire in their capsule during a simulated countdown. In what astronaut Frank Borman called a “failure of imagination,” the space agency was so focused on preventing a fire in space that they did not take the proper precautions to prevent one on the launch pad.
In the end, the NTSB reached the following conclusion about what likely caused the accident.
Probable Cause: The National Transportation Safety Board determines that the probable cause of this accident was Scaled Composites’ failure to consider and protect against the possibility that a single human error could result in a catastrophic hazard to the SpaceShipTwo vehicle. This failure set the stage for the copilot’s premature unlocking of the feather system as a result of time pressure and vibration and loads that he had not recently experienced, which led to uncommanded feather extension and the subsequent aerodynamic overload and in-flight breakup of the vehicle.
The Federal Aviation Administration Office of Commercial Space Transporation’s (FAA AST) main oversight responsibility for commercial human spaceflight is to protect the “uninvolved public” from being injured or killed by a suborbital space plane. The agency came within seconds of failing at that task. Two truck drivers were fortunate to avoid being hit by falling debris from SpaceShipTwo.
As part of its application to the FAA AST for an experimental permit to test SpaceShipTwo, Scaled Composites was required to evaluate how human and software errors could result in a catastrophic failure. The NTSB found that FAA AST granted the initial permit and a permit renewal despite the fact that Scaled had submitted a “deficient” analysis that didn’t meet regulatory requirements.
Rather than requiring Scaled to submit a new analysis, FAA AST issued the company waivers that cited a series of mitigations designed to address the issue. The mitigations included:
- the content and high quality of the crew training program;
- an incremental flight test program in which Scaled Composites “varies only one parameter at a time” from flight to flight;
- the use of chase planes to monitor the flights and assist the pilots;
- a two-pilot system on SpaceShipTwo in which “pilot error on the part of one pilot can be corrected by the other”;
- the remoteness and low population density of the drop zone; and,
- the ability of SpaceShipTwo’s pilots to control the vehicle and steer it away from populated areas.
None of these mitigations was effective in the SpaceShipTwo crash. The low population density barely protected people who were working in the area. The NTSB found Scaled’s training program to be inadequate. Siebold had no time to correct Alsbury’s error. Neither pilot was able to control the ship once the feather began to deploy. And the chase plane was of no help in protecting people on the ground from falling debris.
Scaled and Virgin Galactic didn’t change one variable between the third and fourth powered flights but multiple ones. They changed the type and size of the engine; nearly doubled the intended burn time and maximum altitude; significantly altered the loads on the vehicle; and changed the timing of the feather deployment sequence. Siebold and Alsbury also were going to attempt SpaceShipTwo’s first supersonic reentry. The flight took the concept of incremental testing and twisted it into a pretzel.
Not only were the mitigations ineffective in this situation, the NTSB concluded that FAA AST was deficient in how it issued the waivers.
“The FAA/AST issued the waivers without understanding whether the mitigations would adequately protect against a single human error with catastrophic consequences,” according to the NTSB’s final accident report. “In addition, the FAA/AST did not determine whether mitigations, other than those intended to protect against human error, were sufficient to ensure public safety.”
NTSB investigators also faulted FAA AST for doing an overall poor job on evaluating Scaled’s application.
“The NTSB concludes that the lack of direct communications between FAA/AST technical staff and Scaled Composites technical staff, the pressure to approve experimental permit applications within a 120-day review period, and the lack of a defined line between public safety and mission safety assurance interfered with the FAA’s ability to thoroughly evaluate the SS2 experimental permit applications,” according to the final accident report.
The NTSB found the emergency response that day to be deficient. The first rescue helicopter didn’t arrive at Siebold’s location until 45 minutes after the breakup of SpaceShipTwo. By that time, the injured pilot had sat in the desert for 34 minutes treatment. The delay occurred despite rescuers knowing exactly where Siebold had landed, and the flying time from the Mojave Air and Space Port to his location being a mere 11 minutes.
“The NTSB is concerned that Scaled conducted a high-risk flight test without the on-airport presence of a helicopter that was specifically prepared for and tasked with supporting an emergency response,” the final report states. “The NTSB concludes that Scaled Composites and local emergency response officials could improve their emergency readiness for future test flights by making better use of available helicopter assets.”
The Mercy Air 14 helicopter was eventually called in to transport Siebold to the hospital after medical personnel from two other choppers had treated the pilot. Mercy Air 14 arrived at 11:16 a.m. – 1 hour 9 minutes after SpaceShipTwo had broken up in the sky overhead.
“The NTSB determined that if Mercy Air had been briefed ahead of time about the flight and dispatched immediately after the Extra EA-300L chase plane pilot observed a parachute, the Mercy Air helicopter could have arrived at the pilot’s location about 45 minutes earlier,” the agency said in its final report.
In other words, Mercy Air 14, a fully equipped air ambulance with advanced life-support equipment that was best equipped to respond to the emergency, could have arrived on the scene by around 10:30 a.m. – 12 minutes after Siebold landed in a creosote bush. That would have been about 22 minutes before the first rescue chopper actually arrived.
Pat Williams, who flew the Kern County Fire Department’s helicopter to the scene, told the NTSB he wasn’t pleased with the response. He “characterized the event as ‘fragmented’ and stated ‘it wasn’t good dispatch.’ Afterward he produced a timeline ‘to produce a training point on how not to dispatch an incident.’”
“By definition, a prototype was an unproven, imperfect machine….Some defects were obvious….But other problems…might be discovered late in a program, only after hundreds of hours of flying time. The test pilot’s job was to discover all the flaws, all the potential killers.
Testing was lengthy and complicated, resulting in hundreds of major and minor changes before an aircraft was accepted in the Air Force’s inventory.”
– Chuck Yeager
In the wake of the SpaceShipTwo crash, there were two questions on everyone’s minds. Would Branson continue to fund the program? Was Virgin Galactic capable of finishing the second SpaceShipTwo, completing the flight test program, and safely flying space tourists now that Scaled Composites was out of the picture?
The answer to the first question was a resounding yes. The answer to the second was much murkier.
Branson stood at the Mojave spaceport 24 hours after the crash and made a number of incorrect claims. He said that safety was the highest priority at Virgin Galactic. He claimed that SpaceShipTwo was undergoing the most extensive flight test program in the history of civilian aviation. Branson implied that no one had asked for refunds on their tickets. He also claimed to never have met Alsbury. Not one of those statements was true.
Sources say that by the time of SpaceShipTwo’s fourth and final powered flight, schedule was the drive consideration. The plan was to conduct only a handful of additional tests – with a new engine that had undergone three qualifying tests – before placing Branson and his son, Sam, aboard for the first commercial flight. Virgin Galactic would then begin flying passengers on a proof-of-concept prototype vehicle that Scaled Composites never intended for commercial service.
The plan scared the hell out of people in Mojave. They feared that Virgin and Scaled would push the machine and the men too hard and too fast. They worried the flight test program would fail to uncover all the flaws in the spacecraft before commercial flights began. When the accident occurred, the only real surprise was how it happened. Most people guessed the new engine would fail catastrophically.
As terrible as it sounds, the accident might have saved lives down the road – including those of Richard and Sam Branson. For the Virgin Galactic founder to stand in Mojave and falsely deny having ever met the man who had just died testing his space plane, whose death might make it possible to build a safer vehicle, was just….There were no words for it.
Branson’s claim about the rigor of SpaceShipTwo’s flight test program was bizarre coming from a man who runs multiple airlines. Surely he knew there were no plans to certify the spacecraft in a manner similar to the way commercial aircraft are certified. Customers would fly at their own risk. Virgin was largely protected from lawsuits under the FAA’s informed consent regime and state laws.
All of these claims made people wonder whether Branson really understood the space business he had spent a decade in. There was also the question of whether he and Virgin Galactic were capable of candor with the public and its own ticket holders about the risks involved in human spaceflight.
The Virgin Group is brilliant at marketing, branding, sales and customer service. It has show the ability to safely operate in mature industries such as hotels, resorts, trains and airlines. It is one of the most successful corporations in the world.
However, it has had little experience in actually building anything on its own. Despite some superficial similarities to airlines, manufacturing and operating first-generation passenger spacecraft is a much more challenging endeavor. The technology is immature, and space travel is much more dangerous than aviation is today.
Like NASA’s Apollo 1 fire, the crash of SpaceShipTwo has given Virgin Galactic the opportunity to take its time to build a safer spacecraft and to test it in a rigorous and thorough manner. If the company seizes the opportunity, it might well make a success of its troubled space tourism venture. If so, then Mike Alsbury’s death will not have been in vain.
- Part 1: SpaceShipTwo’s PF04: A High Risk Fight
- Part 2: SpaceShipTwo Pilots Faced Extremely High Work Loads
- Part 3: A Good Light, Then a Fatal Mistake
- Part 3.1: SpaceShipTwo Powered Flight No. 4 Flight Transcript
- Part 3.2: The Breakup of SpaceShipTwo Frame by Frame From the Tail Boom
- Part 4: Pete Siebold’s Harrowing Descent
- Part 4.1: SpaceShipTwo Emergency Response Timeline
- Part 5: Shock, Tears & Spin: The Aftermath of the SpaceShipTwo Crash