Encyclopedia Astronautica
VTOVL



phoeni85.jpg
Phoenix 1985
Credit: Gary Hudson
The concept of a reusable single-stage-to-orbit Vertical Take-Off Vertical Landing (VTOVL) launch vehicle that would reenter and return to its launch site for turnaround and relaunch was first proposed by Philip Bono in the 1960's. The appealing simplicity of the concept has been offset by the technological risk in developing it. The problem with any single-stage-to-orbit concept is that if the empty weight of the final vehicle has been underestimated it will not be able to deliver any payload to orbit, or even reach orbit. Since weight growth of up to 20% is not unknown in aerospace projects, this is a very real threat which has made both NASA and private investors reluctant to invest the billions of dollars it would take to develop a full-scale flight vehicle.

Bono's vehicles proposed minimizing weight by using plug nozzle engines. Cooled by residual hydrogen fuel, these would act as a heat shield for re-entry. More conservatively the recent DC-X designs used a conventional forward heat shield for reentry. The concept was not selected by NASA for the X-33 (an even more risky lifting body design was chosen). This was perhaps the last chance for the concept. The more conservative Kistler recoverable reusable ballistic launch vehicle uses two stages, thereby minimizing the risk.

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Associated Spacecraft
  • New Shepard American manned spacecraft. Flight tests begun 2006. Vertical takeoff/vertical landing suborbital tourist spacecraft being developed by Blue Origin and scheduled to begin commercial operation in 2010. More...

Associated Launch Vehicles
  • Nexus American SSTO VTOVL orbital launch vehicle. Early 1960's recoverable launch vehicle proposed by Krafft Ehricke at General Dynamics. Perhaps the largest conventionally-powered launch vehicle ever conceived, it was designed to deliver 900 tonnes to low earth orbit. More...
  • North American Air Augmented VTOVL North American Aviation's air-augmented vertical takeoff & landing single-stage-to-orbit RLV from 1963 would have used external burning ramjets which, according to preliminary studies would reduce the gross liftoff mass of a VTVL SSTO by up to 30%. More...
  • OOST ISI American SSTO orbital launch vehicle. Alternate version of OOST using Improved Specific Impulse approach: many engines feeding into single large nozzle. More...
  • OOST American SSTO VTOVL orbital launch vehicle. Bono's earliest design for an expendable single-stage-to-orbit LH2/Lox booster. The baseline version used conventional engines. More...
  • ROOST ISI American SSTO orbital launch vehicle. Bono's first design for a reusable single stage to orbit LH2/Lox booster, using Improved Specific Impulse approach: many engines feeding into single large nozzle. More...
  • ROOST American SSTO orbital launch vehicle. Bono's first design for a reusable single stage to orbit LH2/Lox booster, using conventional engines. More...
  • Ares ICBM American intercontinental ballistic missile. The Ares single-stage, liquid-propellant ICBM was the objective of propulsion studies at both Aerojet and Rocketdyne. More...
  • Rombus American SSTO VTOVL orbital launch vehicle. Bono original design for ballistic single-stage-to-orbit (not quite - it dropped liquid hydrogen tanks on the way up) heavy lift launch vehicle. The recoverable vehicle would re-enter, using its actively-cooled plug nozzle as a heat shield. More...
  • Ithacus American SSTO VTOVL orbital launch vehicle. An adaptation of Phillip Bono's enormous ROMBUS plug-nozzle semi-single-stage-orbit launch vehicle as a 1,200 soldier intercontinental troop transport!! The recoverable vehicle would re-enter, using its actively-cooled plug nozzle as a heat shield. More...
  • Pegasus VTOVL American SSTO VTOVL orbital launch vehicle. Bono design for semi-single-stage-to-orbit ballistic VTOVL launch vehicle. Drop tanks were shed on the way to orbit. Pegasus could deliver either a Satun V-size payload to LEO or 172 passengers and their luggage the 12,000 km from Vandenberg to Singapore in 39 minutes. More...
  • SASSTO American SSTO VTOVL orbital launch vehicle. Bono proposal for first step toward VTOVL SSTO vehicle - heavily modified Saturn IVB with plug nozzle engine. More...
  • Beta German SSTO VTOVL orbital launch vehicle. In 1969 rocket pioneer Dietrich Koelle was working at MBB (Messerschmitt-Bolkow-Blohm). There he sketched out a reusable VTOVL design called BETA using Bono's SASSTO as a starting point. The vehicle, taking European technology into account, was a bit heavier than Bono's design. But the thorough analysis showed even this design would be capable of delivering 2 tonnes of payload to orbit. More...
  • MLLV American SSTO VTOVL orbital launch vehicle. Boeing study, 1969, for Saturn follow-on. Plug nozzle, single-stage-to-orbit launch vehicle could itself put 1 million pounds payload into orbit. By addition of up to 12 260 inch solid motors up to 3.5 million pounds payload into orbit with a single launch. More...
  • Gommersall American SSTO VTOVL orbital launch vehicle. Edward Gomersall of NASA's Ames Research Center produced a conservative design for an SSTO in 1970. His vehicle was based on realistic structural technology and used a derivative of the J-2S engine. More...
  • SERV American VTOVL orbital launch vehicle. Chrysler ballistic single stage to orbit alternate shuttle proposal of June 1971. This was the most detailed design study ever performed on a VTOVL SSTO launch vehicle. The 2,040 tonne SERV was designed to deliver a 53 tonne payload to orbit in a capacious 7 m x 18 m payload bay. More...
  • ATV American SSTO VTOVL orbital launch vehicle. George Detko of NASA's Marshall Space Flight Center produced designs for SSTO vehicles as early as 1960. The expendable vehicle had a gross listoff mass of only 22 tonnes, and could deliver a two-person crew to orbit. More...
  • SSOAR American SSTO VTOVL orbital launch vehicle. P Seigler founded a company in 1976 to promote his design for a VTOVL SSTO vehicle using a lox/hydrogen aerospike engine. More...
  • Boeing SPS SSTO American SSTO VTOVL orbital launch vehicle. In 1977 Boeing produced a vehicle design for a 227 tonne payload vertical takeoff launch vehicle to be used to launch components for the huge Satellite Solar Power platforms that NASA was promoting at the time. The booster would launch from the edge of a water-filled man-made lagoon and recover in the lagoon and used a water-cooled heat shield for reentry. More...
  • VTOVL American SSTO VTOVL orbital launch vehicle. Vertical Takeoff Vertical Landing. More...
  • VTOHL 45t American SSTO winged orbital launch vehicle. Vertical Takeoff Horizontal Landing (winged). More...
  • VTOHL 9t American SSTO winged orbital launch vehicle. Vertical Takeoff Horizontal Landing (winged). More...
  • Yakovlev MVKS Russian SSTO winged orbital launch vehicle. In reaction to US X-30 project, government decrees of 27 January and 19 July 1986 ordered development of a Soviet equivalent. The Ministry of Defence issued technical specifications on 1 September for an MVKS, a single-stage reusable aerospaceplane system. The MKVS was to provide effective and economic delivery to near-earth orbit; develop the technology for effective transatmospheric flight; provide super high-speed intercontinental transport, and fulfil military objectives in and from space. It is known that the Tupolev, Yakovlev, and Energia design bureaux submitted designs. No details of the Yakovlev design have become available to date. More...
  • VKS Russian SSTO winged orbital launch vehicle. RKK Energia's proposed solution to the Soviet government's MVKS requirement for a single-stage-to-orbit reusable aerospaceplane system was this 700-metric-ton, turboramjet/rocket mised propulsion design. Work began in 1986 but abandoned when the Soviet Union collapsed. More...
  • Beta II German SSTO VTOVL orbital launch vehicle. Beta II was Dietrich Koelle's nominal 350 tonne lift-off mass SSTO design for launch of a 10 tonne European spaceplane. More...
  • Beta III German SSTO VTOVL orbital launch vehicle. In 1969 Dietrich Koelle proposed his BETA III design. This was to deliver 20 tonnes to orbit with a launch mass of 600 tonnes. In 1996 and 1998 he updated the design for use as an ISS resupply vehicle in place of the shuttle, and as a space tourism vehicle for 100 passengers. More...
  • Beta IV German SSTO VTOVL orbital launch vehicle. Beta II was Dietrich Koelle's largest SSTO concept, with a nominal 2000 tonne lift-off mass SSTO design and 100 tonne payload. More...
  • Phoenix C American SSTO VTOVL orbital launch vehicle. The larger 180 tonne Phoenix design of the 1980's was envisioned in two versions -- the Phoenix C (Cargo, unmanned) and Phoenix E (Excursion -- for use as a lunar or Mars lander and personnel transport to earth orbit). The earlier versions used liquid oxygen oxidiser and two fuels (hydrogen and propane) but later iterations used only oxygen and hydrogen (varying the oxidiser to fuel ration during ascent). The designs used an 'aeroplug' in place of the 'aerospike' of earlier SSTO designs. Gary Hudson and Maxwell Hunter spent several years trying to interest investors in the designs before the company folded. More...
  • Phoenix L American SSTO VTOVL orbital launch vehicle. The small Phoenix design of the 1980's was envisioned in two versions -- the Phoenix L (Light, cargo only) and Phoenix LP (Light-Prime, crewed). The earlier versions used liquid oxygen oxidiser and two fuels (hydrogen and propane) but later iterations used only oxygen and hydrogen (varying the oxidiser to fuel ratio during ascent). The designs used an 'aeroplug' in place of the 'aerospike' of earlier SSTO designs. More...
  • Phoenix M American SSTO VTOVL orbital launch vehicle. Intermediate versions of the Phoenix concept were sketched out in the mid-1980's. These more conservative vehicles used individual altitude-compensating bell nozzles rather than the aeroplug baseline. Composite materials were to be used in the aeroshell and, possibly, in the propellant tankage. More...
  • SSX American SSTO VTOVL orbital launch vehicle. The X-Rocket was a VTOVL SSTO design by Maxwell Hunter II at Lockheed in the late 1980's. The 227 tonne vehicle was powered by clustered RL10 engines. Internal reviews at Lockheed rejected the feasibility of the vehicle. After Hunter retired he worked with Gary Hudson to refine the design as the SSX. This was briefed by the pair to Space Defence Inititive Organization (SDIO) officials in 1988. It was largely through their efforts that the US government funded the DC-X demonstrator in the 1990's. More...
  • VKS-D Russian winged orbital launch vehicle. Air launched from An-225. Release conditions: Piggy-back, 275,000 kg, 38.0 m length x 24.0 m wingspan, 900 kph at 9,500 m altitude. Effective velocity gain compared to vertical launch 270 m/s. More...
  • VKS-RTO+ZhRD Russian winged orbital launch vehicle. Horizontal takeoff, delta winged, single-stage-to-orbit, launch vehicle. Mixed rocket / ramjet propulsion. More...
  • VKS-ZhRD+GPVRD Russian winged orbital launch vehicle. Horizontal takeoff, delta winged, single-stage-to-orbit, launch vehicle. Mixed rocket / scramjet propulsion. More...
  • VKS-G Russian winged orbital launch vehicle. Air launched from Kholod Mach 5 mother ship. This was a Mikoyan supersonic cargo aircraft, designed from Spiral 50-50 design. Combined-cycle turbo-ramjet engine. Release conditions: Piggy-back, 200,000 kg, Mach 5 at 25 to 30 km altitude. Effective velocity gain compared to vertical launch 1130 m/s. It was concluded that the extensive development would be required for the combination-cycle engines, resulting in an extended development schedule and high technical risk. The more conservative subsonic-launched MAKS was chosen instead. More...
  • VKS-O Russian winged orbital launch vehicle. Vertical takeoff, ballistic re-entry, single-stage-to-orbit, Lox/Kerosene/LH2 tripropellant rocket engine powered, reusable launch vehicle. 550 tonne and 770 tonne gross lift-off mass versions considered. More...
  • VKS-R Russian winged orbital launch vehicle. Sled launched, delta winged, single-stage-to-orbit, Lox/LH2 launch vehicle. 290 tonne and 550 tonne versions considered. Studied in tradeoff studies leading to MAKS. Release conditions: Piggy-back, 290,000 kg, Mach 0.5, zero altitude. Effective velocity gain compared to vertical launch 100 m/s. The wheeled sled would get the vehicle up to a velocity where the wings could provide lift, allowing lower-thrust engines to be used than in a vertical-takeoff design. This saved weight, but velocity losses during lifting flight to orbit almost cancelled the advantage, resulting in the approach being unattractive in comparison to pure vertical-launch or air-launch designs. More...
  • VKS-V Russian winged orbital launch vehicle. Vertical takeoff, delta winged, single-stage-to-orbit, Lox/Kerosene/LH2 tripropellant rocket engine powered vehicle. 550 tonne gross liftoff mass and 1000 tonne versions studied. Analogous to NASA's Shuttle-2 and RKK Energia's VKS. More...
  • Aerospatiale VTVL French SSTO VTOVL orbital launch vehicle. Aerospatiale vertical takeoff, vertical landing single stage to orbit study. More...
  • X-30 American SSTO winged orbital launch vehicle. Air-breathing scramjet single stage to orbit. Second attempt after study of similar proposal in early 1960's. Cancelled due to cost, technical challenges. More...
  • Millenium Express American SSTO VTOVL orbital launch vehicle. General Dynamics Space Systems Division proposal for the 1990 SDIO competition was a VTOL SSTO named Millennium Express. The final vehicle was a 15 degree cone with a 20%-length Rocketdyne aerospike engine. Payload was specified as 4500 kg into a polar low earth orbit. The Express could carry on its nose a payload module, a small Apollo-type two-crew seperable manned capsule, or a six-crew module that remained attached to the vehicle for recovery. The similar Douglas Delta Clipper was selected by the USAF for further development. More...
  • VKS-DM Russian winged orbital launch vehicle. Air launched from Gerakl / NPO Molniya-1000 heavy-lift aircraft, catamaran layout, twin-fuselage triplane. Release conditions: Suspended load, 450,000 kg, 900 kph at 9,500 m altitude. Effective velocity gain compared to vertical launch 270 m/s. More...
  • DC-X American VTOVL test vehicle. The DC-X was an experimental vehicle, 1/3 the size of a planned DC-Y vertical-takeoff/vertical-landing, single stage to orbit prototype. It was not designed as an operational vehicle capable of achieving orbital flight. Its purpose was to test the feasibility of both suborbital and orbital reusable launch vehicles using the VTOVL scheme. The DC-X flew in three test series. The first series ran from August 18 to September 30, 1993, before the initial project funding ran out in late October 1993. Additional funding was provided and a second series was conducted June 1994-July 1995. More...
  • DC-X2 American SSTO VTOVL orbital launch vehicle. Proposed intermediate 1/2 scale test vehicle between DC-X and DC-Y orbital version. No government agency was willing to fund the $450 million development cost -- and neither were any private investors. More...
  • DC-Y American SSTO VTOVL orbital launch vehicle. The ultimate goal of the Delta Clipper program, a prototype reusable single-stage to orbit, vertical takeoff/vertical landing space truck. The DC-I Delta Clipper would be the full production version. No government sponsor could be found for the concept and the $ 5 billion development cost was never funded. If it had been funded in 1991, the first DC-Y suborbital flight was predicted for 1995, and a first orbital mission in 1997. More...
  • Kankoh Maru Japanese SSTO VTOVL orbital launch vehicle. Kawasaki design for single stage to orbit reusable booster. Would carry 50 passengers to orbiting hotels or fast intercontinental flights. More...
  • DC-XA American VTOVL test vehicle. After a hard landing in the last flight of this series, the vehicle was rebuilt to the DC-XA configuration. The DC-XA flew from May 1996 until destroyed when it tipped over while landing on its fourth flight on 31 July 1996. More...
  • Orel V7 RSSLV-2 Russian VTOVL orbital launch vehicle. Fully reusable vertical takeoff / vertical landing single stage to orbit. Concept abandoned in favor of Orel V6 by 1998 due to engine reliability concerns. Version with Lox/LH2 propellants. More...
  • Orel V7 RSSLV-3 Russian VTOVL orbital launch vehicle. Fully reusable vertical takeoff / vertical landing single stage to orbit. Concept abandoned in favor of Orel V6 by 1998 due to engine reliability concerns. Tripropellant Lox/Kerosene (RG-1)/LH2 version. More...
  • Roton American SSTO VTOVL orbital launch vehicle. The Roton was a fully reusable, single-stage-to-orbit, vertical take-off and landing piloted space vehicle designed to transport two crew members and 3200 kg of payload to and from a 300 km / 50 degree inclination earth orbit. It used a unique rotor system for recovery. Although a subscale landing test vehicle was built and received enormous media attention, the concept never made much technical sense. More...
  • Venturestar American SSTO winged orbital launch vehicle. Production reusable single-stage-to-orbit launch vehicle using technology developed in X-33 testbed. More...

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