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To Briefly Go: Billionaires Branson & Bezos Battle for Bragging Rights Where Few Have Gone Before

By Doug Messier
Parabolic Arc
July 10, 2021
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Richard Branson wears the SpaceShipTwo flight suit. (Credit: Virgin Galactic)
  • Fewer than 25 suborbital spaceflights have ever been conducted
  • Most suborbital launches were conducted with vehicles retired decades ago
  • No suborbital flight has ever carried a paying passenger
  • There is no agreement on what even constitutes a suborbital spaceflight

by Douglas Messier
Managing Editor

When Richard Branson and three Virgin Galactic employees strap into their seats aboard SpaceShipTwo VSS Unity on Sunday, they will briefly go where not very many have gone before: suborbital space.

Of the 374 attempts to launch astronauts to space since Yuri Gagarin flew into Earth orbit 60 years ago, only 23 were suborbital flights. The majority of those launches were conducted during the 1960’s using vehicles that long ago became museum pieces. One ended with the loss of the spacecraft and its pilot. And two flights were unintentional ones involving vehicles being launched into Earth orbit.

Of the nearly 600 individuals who have been to space, only 20 pilots and one crew member have made suborbital flights. Virgin Galactic’s chief astronaut trainer, Beth Moses, is the only person who was able to float around to enjoy the several minutes of weightlessness that a suborbital spaceflight provides. (She was testing out elements of the passenger cabin for future flights.) All the pilots were strapped securely in their seats flying their vehicles.

Jeff Bezos

Branson and Jeff Bezos — whose suborbital flight aboard Blue Origin’s New Shepard is scheduled for July 20 — won’t be the first billionaires to fly into space. That happened three times during the 2000’s when billionaires flew to the International Space Station aboard Russian Soyuz spacecraft.

However, they will be the first billionaires to fly in suborbital vehicles that their own companies built. And they will be aboard the first spacecraft intended to carry paying passengers and scientific researchers on suborbital flights.

Both billionaires will be participating in flight tests. Virgin Galactic has flown SpaceShipTwo above 50 miles three times. Blue Origin has successfully launched New Shepard 15 times, but never with anyone on board. Bezos and three others will be the first to fly aboard the vehicle.

Defining Suborbital Spaceflight

There are two different definitions of where space begins. The U.S. government has awarded astronaut wings to crew members who have flown above 50 miles (80.5 km). The Federation Aeronautique Internationale (FAI) — an organization that keeps aviation and space records — recognizes 100 km (62.1 miles) as the boundary of space. The table below uses both definitions.

Piloted Suborbital Spaceflights, 1961-2021

VehicleTypeStatusYears of Suborbital FlightsFlights Between 80.5 and 100 km (U.S. Recognized Spaceflight)Flights Above 100+ km (FAI Recognized Spaceflight) Number of Pilots & Crew
X-15 (Retired)Air launched rocket planeRetired1962-681128
Mercury Redstone (MR-4, MR-5)Ballistic missile launched capsuleRetired1961022
SpaceShipOne Air launched rocket planeRetired2004032
SpaceShipTwoAir launched rocket planeActive2018 – present305+
Soyuz*Ballistic missile launched orbital capsuleActive orbital spacecraft not intended for suborbital flights1975, 2018114
*Aborted orbital flight
* Includes four pilots and one crew member
Does not include 15 uncrewed New Shepard flight tests
Credit: Wikipedia

There have been 23 crewed suborbital flights that have carried 20 pilots and one crew member. Fifteen of the flights flew above the U.S. government’s 50-mile (80.5 km) definition of where space begins, while eight exceeded the FAI’s 100 km (62.1 mile) limit. Two of the 23 flights were orbital launches of Soyuz spacecraft that suffered high-altitude aborts due to booster anomalies.

Let’s take a look at the suborbital flights by Virgin Galactic and Blue Origin. We will then examine the 60-year history of crewed flights to this region of space.

Virgin Galactic SpaceShipTwo’s first flight above 50 miles on Dec. 13, 2018. (Credit: Virgin Galactic)

SpaceShipTwo Flights

The SpaceShipTwo program’s powered flight test history is divided into two periods: before and after the accident. VSS Enterprise flew three successful flight before it was destroyed on its fourth powered flight on Oct. 31, 2014. The spacecraft only reached 72,000 ft (21.9 km/13.6 miles) due to limitations caused by hybrid engines that produced serious vibrations in the vehicle. That altitude was achieved after the vehicle was dropped from about 50,000 ft (15.2 km/9.5 miles).

VSS Enterprise was destroyed when the feather system designed to reconfigure the ship for reentry into the Earth’s atmosphere accidentally deployed during powered ascent. Co-pilot Mike Alsbury died in the accident; pilot Pete Siebold parachuted to safety with serious injuries.

SpaceShipTwo VSS Unity & VSS Enterprise Powered Flight Attempts, 2013-21

Flight TypeSuccessesFailuresAbortsTotal
Powered Flight Attempts Between 50-62.1 miles (80.5-100 km) by VSS Unity — U.S. Recognized Spaceflight3014
Powered Flight Attempts Below 50 miles (80.5 km) by VSS Unity3003
Powered Flight Attempts Below 50 miles (80.5 km) — VSS Enterprise (maximum altitude: 72,000 ft/21.9 km)3104
Totals: 91111

The second SpaceShipTwo, VSS Unity, has flown six powered flights, including three above 50 miles (80.5 km) that the U.S. government recognizes as spaceflights. The vehicle also suffered an abort during an attempted spaceflight in December 2020 when a computer rebooted just as the engine was preparing to fire. The crew glided the ship to a safe runway landing.

SpaceShipTwo VSS Unity Flights Above 50 Miles, 2018-21
(Recognized as Spaceflights by U.S. Government)

DateCrewMachMaximum VelocityMaximum AltitudeNotes
December 13, 2018Mark Stucky – C.J. Sturckow2.92,295 mph (3,693 km/h)271,330 ft (51.4 miles/82.7 km)First suborbital flight by SpaceShipTwo
February 22, 2019David Mackay — Michael Masucci — Beth Moses3.042,333 mph (3,755 km/h)295,007 ft (55.9 miles/89.9 km)First suborbital flight with third crew member (Moses) to evaluate passenger experience; vehicle suffered serious damage to horizontal stabilizer that kept it grounded for 14 months; last powered flight from Mojave Air and Space Port
May 22, 2021C.J. Sturckow — David Mackay3.02,302 mph (3,704 km/h)292,776 ft (55.45 miles/89.2 km)Carried NASA-sponsored microgravity experiments; first spaceflight from Spaceport America in New Mexico
Source: Wikipedia

If successful, Branson’s flight will be the fourth time VSS Unity will travel above 50 miles and the 10th powered flight of the eight-year old test program.

Neither VSS Enterprise nor VSS Unity has flown above 100 km (62.1 mile). That has led rival Blue Origin to say Virgin Galactic has not yet flown to space.

New Shepard (NS-14) lifts off from Blue Origin’s Launch Site One in West Texas. (Credits: Blue Origin)

Blue Origin New Shepard Flights

Bezos and three companions will be aboard the 16th launch of the full New Shepard rocket and capsule system. The company also conducted a successful ground abort test that involved only the crew capsule and its escape system.

New Suborbital Spaceflights

Flight TypeSuccessesFailuresPartial FailuresTotal
Capsule Flights Above 62.1 miles (100 km) — FAI Recognized spaceflight120012
Capsule Flights Between 50-62.1 miles (80.5-100 km) — U.S. Recognized Spaceflight1012
Planned In-flight Abort Tests1001
Ground Abort Tests (Capsule Only)1001
Totals: 150116

During 14 flight tests, both the rocket and capsule landed separately back at Blue Origin’s test facility in West Texas. The lone failure occurred on the first launch when the rocket crashed during descent after separating from the crew capsule. The capsule landed safety under parachutes.

Ground crew recover experiments that launched on the reusable New Shepard rocket on which the microgap-cooling technology flew twice. (Credit: Blue Origin)

The capsule used for the in-flight abort test reached 7.1 km (4.4 miles). The rocket, which was expected to explode, survived the abort and flew to an altitude of 93.7 km (58.2 miles) before landing safely back on Earth.

Now that we’ve looked at the two on-going programs, let’s take a trip back 60 years to where crewed suborbital spaceflight began.

John H. Glenn, left, Virgil I. “Gus” Grissom, and Alan B. Shepard, the astronauts selected for the first suborbital mission.(Credit: NASA)

Mercury-Redstone Flights

The United States got human piloted suborbital spaceflight off and running when a NASA Redstone booster sent Alan Shepard 187.5 km (116.5 miles) up into space aboard the Freedom 7 Mercury capsule on May 5, 1961.

Virgil I. “Gus” Grissom followed with a suborbital flight aboard Liberty Bell 7 in July. Grissom’s flight, which reached190.3 km (118.3 miles), remains the highest altitude achieved by a planned suborbital mission. (An aborted Soyuz orbital spacecraft went higher; we will discuss that flight later.)

Crewed Suborbital Mercury Flights
(Recognized as Spaceflights by FAI)

DateCrewVehicleMachMaximum VelocityMaximum AltitudeNotes
May 5, 1961Alan ShepardMercury-Redstone 46.695,134 mph (8,262 km/h)615,120 ft (116.5 miles/187.5 km)First U.S. paceflight
July 21, 1961Virgil “Gus” GrissomMercury-Redstone 56.745,168 mph (8,317 km/h)624,400 ft (118.3 miles/190.3 km)Second U.S. spaceflight; Highest and fastest planned piloted flight above 100 km

The Mercury-Redstone flights were similar to the ones flown by Blue Origin’s New Shepard. Both systems involve single-stage rockets launched vertically from a pad with capsules that land under parachute. The main difference is that while the Mercury and Redstone vehicles were expendable, the New Shepard rocket and capsule are fully reusable.

The suborbital phase of the Mercury program ended with Grissom’s flight. The more powerful Atlas booster launched John Glenn into orbit on Feb. 20, 1962. Three more orbital flights were conducted before the Mercury program ended in 1963.

Mercury’s mix of flights illustrates an important point that is sometimes overlooked: a suborbital spaceflight takes only about three percent of the energy required to put a payload into low Earth orbit. A crewed spaceship returning from a suborbital flight also requires far less protection from the heat of reentry.

Neil Armstrong with the X-15 on the dry lake bed at Edwards Air Force Base, Calif.

X-15 Flights

Eight military and NASA pilots conducted 13 suborbital flights between 1962 and 1968 using the X-15, an air-launched rocket plane that was used to research high-speed and high-altitude flight. The suborbital flights made up a small part of the X-15 program’s 199 total flights.

The three X-15 rocket planes were dropped from under the wing of a modified B-52 bomber, much in the same way that Virgin Galactic’s SpaceShipTwo is launched by its WhiteKnightTwo mother ship.

Suborbital X-15 Flights Above 50 Miles

DateCrewMachMaximum VelocityMaximum AltitudeNotes
August 22, 1963Joseph Walker5.583,794 mph (6,106 km/h)354,200 ft (67.1 miles/108 km)Highest X-15 flight; FAI recognized spaceflight; remained the altitude record for winged suborbital vehicles for 41 years
July 19, 1963Joseph Walker5.53,710 mph (5,971 km/h)347,800 ft (65.9/106 km)First X-15 flight above 100 km; FAI recognized spaceflight
July 17, 1962Robert White5.453,832 mph (6,157 km/h)314,750 ft (59.6 miles/95.9 km)First U.S. recognized spaceflight by winged vehicle
November 1, 1966William Dana5.463,750 mph (6,035 km/h)306,900 ft (58.1 miles/93.5 km)U.S. recognized spaceflight
September 28, 1965John McKay5.333,732 mph (6,006 km/h)295,600 ft (56 miles/90.1 km)U.S. recognized spaceflight
June 27, 1963Robert Rushworth4.893,425 mph (5,512 km/h)285,000 ft (54 miles/86.9 km)U.S. recognized spaceflight
June 29, 1965Joseph Engle4.943,432 mph (5,523 km/h)280,600 ft (53.1 miles/85.5 km)U.S. recognized spaceflight
October 17, 1967William “Pete” Knight5.533,856 mph (6,206 km/h)280,500 ft (53.1 miles/85.5 km)U.S. recognized spaceflight
January 17, 1963Joseph Walker5.473,677 mph (5,918 km/h)271,700 ft (51.5 miles/82.81 km)U.S. recognized spaceflight
August 10, 1965Joseph Engle5.203,550 mph (5,713 km/h)271,000 ft (51.3 miles/82.6 km)U.S. recognized spaceflight; Engle later piloted two space shuttle missions; first man to pilot two winged vehicles back from space
August 21, 1968William Dana5.013,443 mph (5,540 km/h)267,500 ft (50.7 miles/81.5 km)U.S. recognized spaceflight
October 14, 1965Joseph Engle5.083,554 mph (5,720 km/h)266,500 ft (50.5 miles/81.2 km)U.S. recognized spaceflight
November 15, 1967Michael J. Adams5.203,570 mph (5,745 km/h)266,000 ft (50.4 miles/81.1 km)Adams killed when X-15 broke up in flight; pilot awarded astronaut wings; U.S. recognized spaceflight
Source: Wikipedia

Eleven of the 13 suborbital flights reached between 50 and 62.1 miles (80.5 and 100 km) while two flew above 62.1 miles (100 km). The eight pilots who flew the missions were awarded astronaut wings.

Joseph Walker was the only pilot to fly above 100 km; he did so twice in 1963. His second flight reached a record 354,200 ft (67.1 miles/108 km), a record for winged vehicles that would stand for 41 years until it was broken by Scaled Composites pilot Brian Binnie aboard SpaceShipOne in 2004.

Maj. Michael J. Adams with a X-15 at Edwards Air Force Base, Calif. (Credit: NASA)

Both Walker and Joseph Engle flew the X-15 above 50 miles. Engle would later to go on to fly two space shuttle missions, becoming the first astronaut to fly two different types of winged vehicles back from space.

There was one in-flight fatality in the program. On Nov. 15, 1967, Maj. Michael J. Adams lost control of an X-15 while reentering the Earth’s atmosphere after reaching an altitude of 81.1 km (50.4 miles). He was killed when the fuselage broke up and crashed in the Mojave Desert. The U.S. Air Force posthumously awarded astronaut wings to Adams.

The X-15 program ended in December 1968, having obtained a maximum speed of Mach 6.7. It was a highly successful research program that contributed valuable knowledge for the space shuttle program. It would be 35 years before anyone else would fly suborbital by design.

Mike Melvill stands atop SpaceShipOne after a suborbital flight on Sept. 29, 2004. (Credit: RenegadeAven)

SpaceShipOne Flights

SpasceShipOne is an experimental winged vehicle that was dropped at high altitude by the White Knight carrier aircraft. SpaceShipTwo’s predecessor was designed and built by Burt Rutan and his team at Scaled Composites to win the $10 million Ansari X Prize as the first privately built, reusable human spacecraft capable of flying three people above 100 km (62.1 miles) twice in two weeks. Billionaire Paul Allen backed the program with $28 million.

SpaceShipOne made three flights above 100 km in 2004. Two Scaled Composites pilots, Mike Melvill and Brian Binnie, were awarded astronauts wings by the Federal Aviation Administration (FAA) for their flights.

Suborbital SpaceShipOne Flights, 2004
(Recognized as Spaceflights by FAI)

DateCrewMachMaximum VelocityMaximum AltitudeNotes
June 21, 2004Mike Melvill2.92,225 mph (3,581 km/h)328,491 ft (62.2 miles/100.1 km)First private suborbital spaceflight
September 29, 2004Mike Melvill2.922,240 mph (3,605 km/h)337,697 ft (64 miles/102.9 km)Second private suborbital spaceflight; first of two flights for $10 million Ansari X Prize
October 4, 2004Brian Binnie3.092,225 mph (3,581 km/h)367,500 ft (69.6 miles/112 km)Second of two flights for $10 million Ansari X Prize; highest piloted suborbital flight by a winged vehicle, breaking 41-year old record set by Joseph Walker in the X-15

None of the flights carried passengers in the two seats located behind the pilot. SpaceShipOne carried additional mass to simulate the weight of two passengers on the Ansari X Prize flights.

Binnie set a new altitude record for winged vehicles when he flew SpaceShipOne to 69.6 miles (112 km) on the second Ansari X Prize flight. Binnie broke the 41-year old record of 67.1 miles/108 km that Joseph Walker set in the X-15 in 1963.

SpaceShipOne’s flight history consisted of 17 flights. They incluyded: six powered flights, three of which reached altitudes below 100 km (62.1 miles); eight glide flights; and three captive carry flights during which SpaceShipOne never separated from White Knight.

Rutan wanted to continue flying SpaceShipOne with passengers aboard. However, Allen had been unnerved by various close calls during the flight test program. He also had an offer to donate the vehicle to the National Air and Space Museum. So, SpaceShipOne was retired after the second Ansari X Prize flight.

Branson’s Virgin Galactic licensed the SpaceShipOne technology and partnered with Rutan’s Scaled Composites to build the larger SpaceShipTwo suborbital vehicle and WhiteKnightTwo mother ship.

Astronaut Nick Hague (left) and Roscosmos General Director Dmitry Rogozin after the former’s Soyuz launch abort. (Credit: Rioscosmos)

Accidental Suborbital Flights

Two orbital Soyuz launches became accidental suborbital flights due to anomalies with their Soyuz boosters. The first occurred in 1975, the second in 2018.

Accidental Suborbital Flights Above 50 Km

DateCrewVehicleMaximum AltitudeNotes
April 5, 1975Vasily Lazarev, Oleg MakaronSoyuz 18a629,921 ft (119.3 miles/192 km)Orbital flight to Salyut 4 space station aborted after third stage ignited with second stage still attached; highest piloted suborbital flight.
October 11, 2018Alexy Ovchinin,
Nick Hague
Soyuz MS-10305,118 ft (57.8 miles/93 km)Orbital flight to the International Space Station aborted after Soyuz rocket stage failed to separate properly from second stage; recognized as a suborbital flight by the United States but not by the FAI.

Soviet cosmonauts Vasily Lazarev and Oleg Makaron were headed for a 60-day stay aboard the Salyut 4 space station when the third stage of their booster failed to separate from the second stage. Only three of the six locks connecting the stages released. An automated program aborted the launch, exposing the two cosmonauts to a harrowing descent during which they experienced a punishing 21.3 g (209 m/s²)

Makarov made two more Soyuz flights to the Salyut 6 space station. Lazarev never fully recovered from injuries he suffered from the flight and never flew to space again.

Russian cosmonaut Alexy Ovchinin and NASA astronaut Nick Hague suffered a much milder abort in October 2018 due to a booster separation anomaly on a Soyuz launch to the International Space Station. Neither man was injured; both would fly to the station aboard a Soyuz spacecraft in March 2019.

Suffice to say, both Soyuz crews were too busy with their separate emergencies to enjoy their brief trips to space. They were fortunate the abort systems worked and that they survived the flights.

The only other launch abort involving a crewed Soyuz spacecraft occurred in September 1983. An escape tower pulled the Soyuz T-10-1 spacecraft away from its Soyuz booster, which had caught fire on the launch pad. Soviet cosmonauts Vladimir Titov and Gennadi Strekalov were badly shaken but otherwise unharmed. Both would later fly to space.