The Thor-Able was an American expendable launch system used for a series of re-entry vehicle tests and spacecraft launches between 1958 and 1960 .
31-779: It was a two-stage rocket , consisting of a Thor IRBM as a first stage and a Vanguard -derived Able second stage. For satellite or space probe launches, an Altair solid rocket motor was added as a third stage. It was a member of the Thor family and an early predecessor of the Delta . The Able upper stage name represents its place as the first in the series, from the Joint Army/Navy Phonetic Alphabet . Sixteen Thor-Able were launched, nine on sub-orbital re-entry vehicle test flights, four on probe and three on orbital satellite launch attempts. Six of
62-437: A rocket -like second stage. The airplane elements can be wings, air-breathing engines, or both. This approach appeals because it transforms Earth's atmosphere from an obstacle into an advantage. Above a certain speed and altitude, wings and scramjets cease being effective, and the rocket is deployed to complete the trip to orbit. Saenger (spacecraft) was among the first concepts of this type. While not an orbital vehicle,
93-450: A Venus probe, technical delays caused it to be launched after the 1959 Venus window had closed so that it was instead sent into a heliocentric orbit . The final Thor-Able launch was Thor-Able 148 , orbiting Tiros-1 on 1 April 1960. Two-stage-to-orbit A two-stage-to-orbit ( TSTO ) or two-stage rocket is a launch vehicle in which two distinct stages provide propulsion consecutively in order to achieve orbital velocity. It
124-524: A radio guidance package mounted on the Able stages. It saw its first test on 23 April 1958 when Thor-Able 116 was launched from LC-17A with a biological nose cone containing a mouse named MIA (Mouse In Able). At 19:10 EST, the Thor's engine ignited and drove the Able stage and its passenger into the sky. Two minutes and fifteen seconds after launch, at an altitude of 50 miles (80 km), the Thor exploded and sent
155-414: A record distance of 36.2 million km (22.5 million miles) on 26 June 1960, although it was much too weak by then to acquire data. In common with Explorer 6 , Pioneer 5 used the earliest known digital telemetry system used on spacecraft, codenamed "Telebit", which was a tenfold (or 10 dB) improvement in channel efficiency on previous generation "Microlock" analog systems in use since Explorer 1 and
186-473: A two-stage design should require less maintenance, less testing, experience fewer failures and have a longer working life. In addition the two-stage approach allows the lower stage to be optimized for operation in the Earth's lower atmosphere, where pressure and drag are high, while the upper stage can be optimized for operation in the near-vacuum conditions of the later part of the launch. This allows an increase in
217-400: Is intermediate between a three-stage-to-orbit launcher and a hypothetical single-stage-to-orbit (SSTO) launcher. At liftoff the first stage is responsible for accelerating the vehicle. At some point the second stage detaches from the first stage and continues to orbit under its own power. An advantage of such a system over single-stage-to-orbit is that most of the dry mass of the vehicle
248-402: Is not carried into orbit. This reduces the cost involved in reaching orbital velocity, as much of the structure and engine mass is ejected, and a larger percentage of the orbited mass is payload mass. An advantage over three or more stages is a reduction in complexity and fewer separation events , which reduces cost and risk of failure. It is not always clear when a vehicle is a TSTO, due to
279-459: The Ariane 5 or most Atlas V variants (all except the 401 and 501). With reference to a reusable launch system this approach is often proposed as an alternative to single-stage-to-orbit (or SSTO ). Its supporters argue that, since each stage may have a lower mass ratio than an SSTO launch system, such a system may be built further away from limits of its structural materials. It is argued that
310-572: The Pioneer/Able series. The original mission plan was for a launch in November 1959 where Pioneer 5 would conduct a flyby of Venus, but technical issues prevented the launch from occurring until early 1960 by which time the Venus window for the year had closed. Since it was not possible to send the probe to Venus, it would instead merely investigate interplanetary space and an actual mission to
341-494: The Thor exploded 77 seconds into the launch due to another turbopump malfunction. After an Atlas missile test a month later also failed due to the turbopumps, the Air Force Ballistic Missile Division quickly replaced the pumps in all of their missiles and this problem did not repeat itself again. On 10 October, Pioneer 1 was launched on Thor-Able 130 . The second stage shut down too early and
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#1732773204724372-632: The VTOL option design workable. Other designs like the DH-1 concept take it a step further and use a 'pop-up/pop-down' approach, which delivers the orbiting stage to a point about 60 km above the Earth's surface, before dropping down to the launch pad again. In the case of the DH-1, the upper stage is effectively an 'almost SSTO' with a more realistic mass fraction and which was optimised for reliability. Some TSTO designs comprise an airplane -like first stage and
403-466: The biggest single improvement in signal encoding on western spacecraft. The spacecraft received the uplink carrier at 401.8 MHz and converted it to a 378.2 MHz signal using a 16/17 coherent oscillator circuit. The telemetry system phase modulated a 512 Hz subcarrier, which was in turn amplitude modulated at 64, 8, or 1bit/s. The spacecraft was unable to aim its antennas, and so had no high-gain dish antenna common on later spacecraft. Instead,
434-487: The biological nose cone was driven back into the atmosphere for a splashdown in the South Atlantic, but recovery crews failed to locate the capsule and it sank into the ocean. A third attempt was made on 23 July. The press refused to call the mouse by the name of MIA III, so she was instead christened "Wickie", after a local female news reporter who had covered the space program at Cape Canaveral. Unfortunately, Wickie
465-547: The case of airplane-like lower stages they also argue how difficult and expensive high speed aircraft (like the SR-71 ) are to develop and operate, and question performance claims. Many 'mini-shuttle' designs that use transport aircraft as first stages also face similar problems with ice/foam as the Space Shuttle due to the requirement they also carry a large external tank for their fuel. As of 2023, SpaceX and NASA are
496-487: The first one, which failed to stage due to an electrical problem and fell into the Atlantic Ocean. On 7 August, Explorer 6 (a scientific satellite) was launched on Thor-Able 134 and successfully orbited. On 17 September, Transit 1A on Thor-Able 136 failed to orbit due to the third stage again failing to ignite. On 3 November, Pioneer 5 was successfully launched on Thor-Able 219 . Intended originally as
527-450: The hapless rodent into the Atlantic Ocean instead of space. The cause of the failure was traced to a turbopump bearing coming loose and resulting in pump shutdown and instant loss of thrust. With no attitude control, the Thor pitched down and its LOX tank ruptured from aerodynamic loads. On 9 July, Thor-Able 118 lifted off for a second attempt with a mouse named MIA II. The booster, including the unproven Able stage, performed successfully and
558-553: The interplanetary region. The micrometeorite counter failed to operate as the data system saturated and failed to operate properly. The recorded digital data were transmitted at 1, 8, and 64 bit/s, depending on the distance of the spacecraft from Earth and the size of the receiving antenna. Weight limitations on the solar cells prevented continuous operation of the telemetry transmitters. About four operations of 25 min duration were scheduled per day with occasional increases during times of special interest. A total of 138.9 h of operation
589-417: The launches resulted in failures, in which three of those were the result of the additional Altair upper stage, added to the rocket to allow it to launch spacecraft beyond a sub-orbital trajectory. All sixteen launches occurred from Cape Canaveral Air Force Station Launch Complex 17A . The Thor-Able vehicle had a stronger airframe than the standard Thor IRBM and had the inertial guidance system replaced by
620-515: The only launch providers which have achieved first-stage reuse of an orbital vehicle with SpaceX’s two-stage Falcon 9 and 2.5-stage Falcon Heavy , and NASA’s Space Shuttle Solid Rocket Boosters . Rocket Lab has recovered multiple first stages of their Electron rocket, but has not flown it again. Taking the view that airplane like operations do not translate to airplane-like appearance, some reusable TSTO concepts have first stages that operate as VTOL or VTOHL aircraft. The DC-X has proven
651-443: The payload mass fraction of a two-stage vehicle over single-stage or stage-and-a-half vehicles, which have to perform in both environments using the same hardware. Critics argue that the increased complexity of designing two separate stages that must interact, the logistics involved in returning the first stage to the launch site, and the difficulties of conducting incremental testing on a second stage will outweigh these benefits. In
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#1732773204724682-479: The planet would have to wait another three years. The spacecraft was a 0.66 metres (2 ft 2 in) diameter sphere with four solar panels that spanned over 1.4 metres (4 ft 7 in) and it was equipped with four scientific instruments: Booster performance during launch was overall excellent considering the numerous earlier difficulties with the Thor-Able vehicle. There were some minor anomalies with
713-531: The probe did not have sufficient velocity to escape Earth's gravity. It re-entered the atmosphere and burned up 43 hours after launch. Pioneer 2 was launched on 8 November ( Thor-Able 129 ) and reentered the atmosphere less than an hour after launch when the third stage failed to ignite. The next six Thor-Able flights were suborbital tests for the Air Force (23 January, 28 February, 21 March, 8 April, 20 May, and 11 June 1959). All of these were successful except
744-567: The rocket component itself is composed of multiple stages. Pioneer 5 Pioneer 5 (also known as Pioneer P-2 , and Able 4 , and nicknamed the "Paddle-Wheel Satellite" ) was a spin-stabilized space probe in the NASA Pioneer program used to investigate interplanetary space between the orbits of Earth and Venus . It was launched on 11 March 1960 from Cape Canaveral Air Force Station Launch Complex 17A at 13:00:00 UTC with an on-orbit dry mass of 43 kilograms (95 lb). It
775-415: The second stage flight control system that resulted in unplanned pitch and roll motions, however, they were not enough to endanger the mission. The spacecraft returned data collected by the magnetometer on the magnetic field and it measured that the median undisturbed interplanetary field was approximately 5 γ ± 0.5 γ in magnitude. The spacecraft also measured solar flare particles, and cosmic radiation in
806-481: The successful private SpaceShipOne suborbital spacecraft developed for the Ansari X Prize demonstrated that a two-stage system with a winged aircraft as the "lower half" can reach the edge of space . The team behind SpaceShipOne has built and flown a commercial sub-orbital launch system — SpaceShipTwo — based on this technology. The Pegasus rocket while airplane launched, is not a two-stage-to-orbit system because
837-479: The system could introduce a 150W amplifier into its normally 5W transmitter circuit. It was powered by a battery of 28 F-size NiCd cells recharged by the solar paddles, allowing up to eight minutes of high power communications before risking damage to the batteries. Each hour of 5W communications or five minutes of 150W communications required ten hours of recharging the batteries. Unlike later interplanetary spacecraft ( Mariner 2 and beyond), this spacecraft did not use
868-611: The use of strap-on booster rockets at launch. These are dropped early on in the flight and may or may not be considered an additional stage if the core engine(s) continue firing. These are sometimes considered half a stage, leading to the expression one-and-a-half-stage-to-orbit (1.5STO) e.g. for the Long March 5B or the Atlas missile , which was a single core stage with additional boosters. Similarly, two-stage designs with additional boosters can be referred to as 2.5-stage rockets e.g.
899-403: Was a 0.66 metres (2 ft 2 in) diameter sphere with 1.4 metres (4 ft 7 in) span across its four solar panels and achieved a solar orbit of 0.806 × 0.995 AU (121,000,000 by 149,000,000 km). Data was received until 30 April 1960. Among other accomplishments, the probe confirmed the existence of interplanetary magnetic fields . Pioneer 5 was the most successful probe in
930-557: Was completed, and over three megabits of data were received. The major portion of the data was received by the Lovell radio telescope at Jodrell Bank Observatory and the Hawaii Tracking Station because their antennas provided grid reception. Data was received until 30 April 1960, after which telemetry noise and weak signal strength made data reception impossible. The spacecraft's signal was detected by Jodrell Bank from
961-430: Was no luckier than her predecessors when recovery crews once again failed to locate the capsule after splashdown, but telemetry data confirmed the mouse's survival from liftoff through reentry and proved comprehensively that living organisms could survive space travel. Attention now turned to Thor-Able 127 and Pioneer 0 , the world's first lunar probe . This flight took place on 17 August, but ended embarrassingly when