- Parabolic Arc
- March 20, 2023
Pete Siebold’s Harrowing Descent
Part 4 in a Series
By Douglas Messier
As far as C.J. Sturckow could tell, everything was going perfectly. Flying an Extra plane at 14,000 feet above Koehn Lake, he and photographer Mark Greenberg watched SpaceShipTwo drop cleanly from WhiteKnightTwo and light its engine. The rocket ignition was “beautiful,” the plume color looked fine, the ship’s trajectory appeared to be right on the mark. And then–
The rocket engine just stopped. Or did it? Sturckow couldn’t tell. The ship was about 30,000 feet over overhead and climbing. Maybe it was an optical illusion, a result of the new engine. But, wait…pieces started falling off the ship. What the–? Sturckow banked the Extra 30 degrees to avoid the falling debris.
A gaseous white cloud enveloped the ship as it continued to climb upward. A small orange flame appeared from within the cloud. Then SpaceShipTwo’s twin tail booms broke off as the entire vehicle disintegrated.
“Knock it off! Knock it off! Knock it off!” test conductor Todd Ericson shouted to the SpaceShipTwo pilots in vain.
Sturckow started looking for parachutes amidst the falling debris. “He thought he saw two distinct objects falling out after about 5-10 seconds… He was surprised to see two objects at the same time. He said it was not easy to egress for the SpaceShipTwo,” according to Sturckow’s NTSB interview summary.
Back in Mojave, officials realized immediately that something had gone seriously wrong. At 10:08 a.m., Kern County Fire Department (KCFD) Assistant Chief Steven Pendergrass text messaged rescue helicopter pilot Pat Williams, who was 37 miles away in Keene, that SpaceShipTwo had “problems with something, they’re coming down.” A minute later, Pendergrass texted, “Get ready.”
As SpaceShipTwo broke up around him, pilot Pete Siebold heard a loud bang and experienced about 9 G’s – nine times the force of gravity. He felt as if all the air was being rapidly sucked out of his lungs as he was thrown free at 50,000 feet while still strapped to his seat.
Clad in a lightweight flight suit, boots and a helmet connected to an emergency oxygen bottle, Siebold had little protection against the extreme elements. The temperature was -69.7 Fahrenheit (-56.5 C), lower than the coldest temperature ever recorded – -41.8 F (-41ºC) – at the summit of Mount Everest. The atmospheric pressure was only 116.0 hPa, only about 11.4 percent of the pressure at sea level.
Siebold suddenly awoke in mid-air to a high-frequency whistling sound. Struggling to see as crystals formed on his eyes in the extreme cold, he saw he was high above the haze layer with the desert far below. His visor had been ripped off by the wind, his helmet and oxygen mask twisted to the left and no longer straight on his face. The wind kept trying to rip his helmet off his head. Still strapped into his seat, Siebold wasn’t tumbling, but falling in a stabilized position with his head slightly down.
Siebold’s memory of this period is incomplete, but he likely tried to activate his emergency oxygen system. It wasn’t working. He instinctively reached for his seatbelt with both hands, unbuckling it with ease and then pushing away from the seat. Siebold spread his arms out and legs apart as he assumed the free fall parachuting position. He then lost consciousness again he fell toward Earth at 135 miles per hour (approximately 60 meters per second).
A “sudden jolt” of the parachute deploying awoke the pilot from his slumber. Siebold later described the parachute opening as “gentlemanly…It was not harsh.” The chute had deployed automatically at 10,870 feet. The pilot looked up and was relieved to see the red-and-white canopy had deployed properly.
“One chute,” Sturckow reported at 10:10 a.m. He began following Siebold down to the deck.
Siebold scanned the skies for another parachute. Where was his co-pilot, Mike Alsbury? Had he gotten out OK?
Although SpaceShipTwo’s drop zone had been carefully selected for its low population density, more people were in the area than normal that Friday morning. A crew was resurfacing Redrock Randsburg Road, which ran to the northwest of Koehn Lake. For those heading to Randsburg, the detour took them first along Neuralia Road and then onto Cantil Road.
On Cantil Road, FedEx deliveryman Ricky Valenzuela drove his truck past a dirt trailer driven by Robert Wright, who was working on a nearby construction job. Seconds later, both drivers heard a loud crash behind them. They stopped immediately, each one fearing the other driver had crashed.
As they got out of their trucks, they saw a field of debris across the road and an aircraft seat on the side of the road beside a crater. Valenzuela ran to the seat and turned it over. He knew immediately there was nothing he could do for the seat’s occupant. A small part of the co-pilot’s drogue chute lay on the ground nearby. Valenzuela likened the scene to the roadside bombs he had seen during his military service in Iraq.
Immediately after the accident, Scaled Composites pilot Mark Stucky opened a hatch in the ceiling of the company’s building in Mojave and climbed out onto the roof in an effort to see what was happening over the drop zone 20 miles to the north. It was cloudy, however, and he saw nothing.
As soon as he heard test conductor Ericson say, “Knock it off!” over the radio, Scaled Composites President Kevin Mickey had rushed back to his office. He arrived two or three minutes later to find two or three employees already there. Mickey and the others began implementing the blue zebra protocol, the processes Scaled used for in-flight emergencies. Soon, eight to 12 people were in his office handling various responsibilities. Emergency ground response units were dispatched.
The families of Siebold and Alsbury were provided with chaperones and taken to a nearby conference room. It then became a “waiting game” for definitive information about the status of the crew. Mickey was not going to tell the families anything until he was absolutely sure of his facts.
At 10:14 a.m., a time honored metaphor was used to inform people in Mojave about what had gone wrong. “Today is a bad day. The spaceship should be here but it is not. There are no further details at this time.”
Flying machines never crashed. And no ever died. They just had bad days. At least until all the facts were in. And that would take a while.
Siebold found his head clearing as he descended under parachute. Everything was happening slower, and he was able to process information better. He had a hard time seeing. His eyes had debris from the ship in them. His right arm was so badly injured he could barely move it. The pilot gave a wave with his other hand to Sturckow and Greenberg as the Extra chase plane circled him.
The winds were strong as he descended from 5,000 to 2,000 feet. Siebold worried about being dragged through the desert by his parachute. Fortunately, the winds calmed below 2,000 feet, and he descended in “a very slow spiral with no noticeable ground track” toward the desert floor.
Siebold tried to reach the parachute’s risers to position himself properly for landing. He was worried about re-injuring his left foot, which he had hurt in an accident several years earlier. But he couldn’t reach them with his injured right arm. Nor could he fix the dislocation in his limb.
As he ran out of time and altitude, he put his hands at his side and bent his knees and feet. Unable to roll to one side because he lacked directional control, Siebold fell forward into a creosote bush. The parachute drifted over the bush.
The time was 10:18 a.m. It had been about 11 minutes minutes since SpaceShipTwo broke up.
“He sat up and began to become more aware of the severity of his injuries,” according to a NTSB interview summary. “His eyesight continued to degrade and was painful. He could not keep his eyes open and he never opened his right eye again until the emergency responders arrived. His right arm was bleeding and his flight suit was saturated with blood but it did not appear to be actively bleeding so he was ‘not overly concerned about it.’ He did not perceive any lower body injuries.”
Siebold tried to remove his parachute harness, but he stopped after hearing a “clunking noise” in his chest. Fearing a possible spinal fracture, he decided to stay exactly where he was until emergency responders arrived. He would only deal with the parachute if the wind picked up and threatened to drag him across the scrub brush. Siebold’s right thumb was numb, as if he had been throwing snowballs without gloves.
He waved to Sturckow and Greenberg in the Extra chase plane as it circled overhead. Sturckow radioed the position to mission control and departed to search for the other pilot and SpaceShipTwo debris.
Just as Siebold landed, Assistant Fire Chief Pendergrass text messaged Williams to launch the rescue helicopter from Keeene. But, it would take a while to get the chopper airborne.
“The helicopter pilot reported that, because this method of dispatch was not standard operating procedure, he had to await dispatch instructions from the Kern County Emergency Communications Center [ECC], which provided dispatch instructions about 10:23, five minutes after the on-scene commander’s instruction to launch,” according to the NTSB’s final report.
It would take another seven minute, until 10:30 a.m., before KCFD’s rescue helicopter would take off from Keene. This was more than 20 minutes after Pendergrass had notified them of a problem with the SpaceShipTwo flight and to “be ready” to rapidly respond.
Meanwhile, the helicopter most capable of responding to the accident wasn’t even available. At the very moment SpaceShipTwo was breaking up, Mercy Air 14 – a fully equipped medevac helicopter that operates under contract to Kern County – was in the air over the Mojave spaceport. The helicopter was out of service as pilot Edmund Keefe and a mechanic conducted a maintenance flight to calibrate the helicopter’s compass.
As was typical for SpaceShipTwo flight tests, Mercy Air crew had not been included in the pre-flight safety preparations. Thus, they were not on standby to respond if anything went wrong with the test. “If they let us know we could have scheduled [maintenance] around [the launch],” said David Wells, Mercy Air 14’s lead pilot.
Keefe and the technician finished the compass test and were heading back to their base on the flight line when Keefe heard a “request for the helicopter” on the Mojave tower frequency. At this same time, Mercy Air flight nurse Kathy Branson and flight medic Brent Eichelberger were outside the company’s hangar waiting for SpaceShipTwo to land. They suddenly noticed activity at the National Test Pilot School located just down the flight line. People were frantically pulling a Huey out of the hangar and cold starting it.
Keefe landed Mercy Air 14 and saw the activity at NTPS during his post-flight walk around. He told Branson to call the Kern County ECC to place the helicopter back in service. Branson asked ECC if it wanted Mercy Air 14 to launch, but the helicopter crew was put on standby instead.
“It was strange to me that they did not want us to launch, because we all knew that there had been a major malfunction with the rocket, and at least one parachute had deployed,” Keefe told NTSB investigators.
Mojave spaceport CEO/General Manager Stu Witt had driven over to the test pilot school and asked CEO Al Peterson to launch the school’s Huey, call sign Tiger 08. Witt said the decision was “launched as an audible, basically because we could and had the resources.”
Peterson told Witt that he needed 15 minutes to launch the helicopter; he did it in less than 14 minutes. At 10:41 a.m., Peterson took off with EMT Patrick Campbell, Flight Surgeon Joseph “Chuck” Antonio, and a NTPS photographer. Peterson told them to be on the look out for other helicopters and aircraft responding to the scene.
Guided by Sturckow in the chase plane, it took Peterson 11 minutes to reach Siebold’s location. It was 10:52 a.m, some 45 minutes after SpaceShipTwo broke up in the sky overhead. Siebold had been lying in the desert for more than half an hour.
The helicopter landed about 100 yards away to avoid exposing the injured pilot to rotor wash. Campbell exited with Antonio and photographer, who acted as his medical assistants. Deputies from the Kern County Sheriff’s Office (KCSO) were also on scene to help.
“I observed a contusion over his right eye and, asked him if he had any additional injuries, and he stated that he had a sore right shoulder, possible broken right arm, injuries to his right wrist and possible broken right ribs,” Campbell said in a statement to the NTSB. “We supported his neck and used KCSO deputies for inline immobilization. We used his parachute as stabilization and to protect him from rotor wash, and the elements.”
Campbell was “very concerned” about Siebold’s exposure to high altitude and possible decompression injuries. He placed the patient on high-flow oxygen, to which Siebold responded well. The EMT also saw what appeared to be first and second degree burns on the pilot’s right wrist.
Throughout the treatment, Siebold kept his eyes closed. Campbell “retrieved a sterile water solution from his bag and attempted to clean the dirt and debris out of his eyes while supporting his head and neck. The pilot eventually opened his left eye but never opened his right eye.”
By now, Siebold had begun to realize the magnitude of the accident. Campbell “noticed the pilot’s first name on his name tag and asked if he knew the whereabouts of the copilot. The pilot’s response was garbled but stated that he did not think the copilot made it out of the vehicle,” according to a NTSB interview summary.
At 10:56 a.m., Williams landed the KCFD helicopter. The county rescue crew took over assisting Campbell from the flight surgeon and photographer. Campbell rejected a suggestion to use an ambulance that was already in the area to transport Siebold to the hospital. He wanted Mercy Air 14, which had advanced life support equipment. Williams made the call to the Kern County ECC.
At 10:59 a.m., Kern County ECC dispatched Mercy Air 14 to Siebold’s location. Keefe took off with Branson and Eichelberger aboard. As they flew north, Campbell and his assistants used the backboard, trauma gear and scoop litter from the KCFD helicopter to package Siebold for transport.
Mercy Air 14 arrived at 11:15 a.m. Eichelberger climbed out of the helicopter and did the initial assessment of Siebold on ground. Campbell briefed him on the pilot’s condition, and together they prepared him to be moved. “The ground team did a great job packaging the victim and getting him into our helicopter,” Keefe said in an NTSB statement.
At 11:23 a.m., Mercy Air 14 took off and headed south toward Lancaster. “During flight I asked if he was having pain,” Branson wrote in her statement to NTSB. “He was able to tell me that he had pain rated at an 8. I asked if he was able to recall what happened and he responded yes. Upon arrival at the hospital he was able to tell me his full name and date of birth.”
Branson and Eichelberger attempted to start an IV with pain medication on Siebold’s left arm because his right one was injured. This proved to be difficult because the left arm was positioned along the left sidewall of the helicopter. They succeeded as the helicopter was touching down at the hospital. It was 11:53 a.m., an hour and 44 minutes after SpaceShipTwo broke up in the sky near Koehn Lake.
- 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