Blue Origin NS-22
94-517: (Redirected from Command Module ) Command module may refer to: The Apollo command module , the crew cabin used in the Apollo program designed specifically to return through the atmosphere to a water landing The crew module of the Orion spacecraft , designed to function similarly to the Apollo command module An electronic control unit used to control
188-411: A is more than R /2. The specific orbital energy ϵ {\displaystyle \epsilon } is given by: ε = − μ 2 a > − μ R {\displaystyle \varepsilon =-{\mu \over {2a}}>-{\mu \over {R}}\,\!} where μ {\displaystyle \mu \,\!}
282-534: A mother ship , which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module , to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown ; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during
376-552: A 400 Ah auxiliary battery was added to the SM for emergency use. Apollo 13 had drawn heavily on its entry batteries in the first hours after the explosion, and while this new battery could not power the CM for more than 5–10 hours it would buy time in the event of a temporary loss of all three fuel cells. Such an event had occurred when Apollo 12 was struck twice by lightning during launch. Sub-orbital spaceflight A sub-orbital spaceflight
470-410: A LEO. On a 10,000-kilometer intercontinental flight, such as that of an intercontinental ballistic missile or possible future commercial spaceflight , the maximum speed is about 7 km/s, and the maximum altitude may be more than 1300 km. Any spaceflight that returns to the surface, including sub-orbital ones, will undergo atmospheric reentry . The speed at the start of the reentry is basically
564-471: A crew of two pilots, to an altitude of 200 km (65,000 ft) using captured V-2 . In 2004, a number of companies worked on vehicles in this class as entrants to the Ansari X Prize competition. The Scaled Composites SpaceShipOne was officially declared by Rick Searfoss to have won the competition on October 4, 2004, after completing two flights within a two-week period. In 2005, Sir Richard Branson of
658-454: A distinct boundary between atmospheric flight and spaceflight . During freefall the trajectory is part of an elliptic orbit as given by the orbit equation . The perigee distance is less than the radius of the Earth R including atmosphere, hence the ellipse intersects the Earth, and hence the spacecraft will fail to complete an orbit. The major axis is vertical, the semi-major axis
752-467: A flashing rendezvous beacon visible from 54 nautical miles (100 km) away as a navigation aid for rendezvous with the LM. The SM was connected to the CM using three tension ties and six compression pads. The tension ties were stainless steel straps bolted to the CM's aft heat shield. It remained attached to the command module throughout most of the mission, until being jettisoned just prior to re-entry into
846-500: A flight is attained at the lowest altitude of this free-fall trajectory, both at the start and at the end of it. If one's goal is simply to "reach space", for example in competing for the Ansari X Prize , horizontal motion is not needed. In this case the lowest required delta-v, to reach 100 km altitude, is about 1.4 km/s . Moving slower, with less free-fall, would require more delta-v. Compare this with orbital spaceflights:
940-511: A lift off from Texas and a simulated soft touchdown in the Indian Ocean 66 minutes after liftoff. Sub-orbital flights can last from just seconds to days. Pioneer 1 was NASA 's first space probe , intended to reach the Moon . A partial failure caused it to instead follow a sub-orbital trajectory, reentering the Earth's atmosphere 43 hours after launch. To calculate the time of flight for
1034-482: A low Earth orbit (LEO), with an altitude of about 300 km, needs a speed around 7.7 km/s, requiring a delta-v of about 9.2 km/s. (If there were no atmospheric drag the theoretical minimum delta-v would be 8.1 km/s to put a craft into a 300-kilometer high orbit starting from a stationary point like the South Pole. The theoretical minimum can be up to 0.46 km/s less if launching eastward from near
SECTION 10
#17327803233241128-627: A means of docking the command module to a lunar excursion module (LEM) . But the change to lunar orbit rendezvous, plus several technical obstacles encountered in some subsystems (such as environmental control), soon made it clear that substantial redesign would be required. In 1963, NASA decided the most efficient way to keep the program on track was to proceed with the development in two versions: By January 1964, North American started presenting Block II design details to NASA. Block I spacecraft were used for all uncrewed Saturn 1B and Saturn V test flights. Initially two crewed flights were planned, but this
1222-765: A minimum-delta-v trajectory, according to Kepler's third law , the period for the entire orbit (if it did not go through the Earth) would be: period = ( semi-major axis R ) 3 2 × period of low Earth orbit = ( 1 + sin θ 2 ) 3 2 2 π R g {\displaystyle {\text{period}}=\left({\frac {\text{semi-major axis}}{R}}\right)^{\frac {3}{2}}\times {\text{period of low Earth orbit}}=\left({\frac {1+\sin \theta }{2}}\right)^{\frac {3}{2}}2\pi {\sqrt {\frac {R}{g}}}} Using Kepler's second law , we multiply this by
1316-466: A mission. An umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and allowed to burn up in the atmosphere. The CSM was developed and built for NASA by North American Aviation starting in November 1961. It was initially designed to land on
1410-484: A motor vehicle system or subsystem Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Command module . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Command_module&oldid=921292820 " Category : Disambiguation pages Hidden categories: Short description
1504-480: A pore seal, a moisture barrier (a white reflective coating), and a silver Mylar thermal coating that looks like aluminum foil. The heat shield varied in thickness from 2 inches (5.1 cm) in the aft portion (the base of the capsule, which faced forward during reentry) to 0.5 inches (1.3 cm) in the crew compartment and forward portions. The Total weight of the shield was about 3,000 pounds (1,400 kg). The 1-foot-11-inch (0.58 m)-tall forward compartment
1598-478: A quarter of the way around the Earth, and 42 minutes for going halfway around. For short distances, this expression is asymptotic to 2 d / g {\displaystyle {\sqrt {2d/g}}} . From the form involving arccosine, the derivative of the time of flight with respect to d (or θ) goes to zero as d approaches 20 000 km (halfway around the world). The derivative of Δ v also goes to zero here. So if d = 19 000 km ,
1692-402: A so-called 'soft dock' state and enabled the pitch and yaw movements in the two vehicles to subside. Excess movement in the vehicles during the 'hard dock' process could cause damage to the docking ring and put stress on the upper tunnel. A depressed locking trigger link at each latch allowed a spring-loaded spool to move forward, maintaining the toggle linkage in an over-center locked position. In
1786-559: Is a spaceflight in which the spacecraft reaches outer space , but its trajectory intersects the surface of the gravitating body from which it was launched. Hence, it will not complete one orbital revolution, will not become an artificial satellite nor will it reach escape velocity . For example, the path of an object launched from Earth that reaches the Kármán line (about 83 km [52 mi] – 100 km [62 mi] above sea level ), and then falls back to Earth,
1880-423: Is as scientific sounding rockets . Scientific sub-orbital flights began in the 1920s when Robert H. Goddard launched the first liquid fueled rockets, however they did not reach space altitude. In the late 1940s, captured German V-2 ballistic missiles were converted into V-2 sounding rockets which helped lay the foundation for modern sounding rockets. Today there are dozens of different sounding rockets on
1974-435: Is between 0 and μ 2 R {\displaystyle \mu \over {2R}\,\!} . To minimize the required delta-v (an astrodynamical measure which strongly determines the required fuel ), the high-altitude part of the flight is made with the rockets off (this is technically called free-fall even for the upward part of the trajectory). (Compare with Oberth effect .) The maximum speed in
SECTION 20
#17327803233242068-624: Is considered a sub-orbital spaceflight. Some sub-orbital flights have been undertaken to test spacecraft and launch vehicles later intended for orbital spaceflight . Other vehicles are specifically designed only for sub-orbital flight; examples include crewed vehicles, such as the X-15 and SpaceShipTwo , and uncrewed ones, such as ICBMs and sounding rockets . Flights which attain sufficient velocity to go into low Earth orbit , and then de-orbit before completing their first full orbit, are not considered sub-orbital. Examples of this include flights of
2162-468: Is defined as a missile that can hit a target at least 5500 km away, and according to the above formula this requires an initial speed of 6.1 km/s. Increasing the speed to 7.9 km/s to attain any point on Earth requires a considerably larger missile because the amount of fuel needed goes up exponentially with delta-v (see Rocket equation ). The initial direction of a minimum-delta-v trajectory points halfway between straight up and straight toward
2256-528: Is different from Wikidata All article disambiguation pages All disambiguation pages Apollo command and service module#Command module (CM) The Apollo command and service module ( CSM ) was one of two principal components of the United States Apollo spacecraft , used for the Apollo program , which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as
2350-1134: Is maximized (at about 1320 km) for a trajectory going one quarter of the way around the Earth ( 10 000 km ). Longer ranges will have lower apogees in the minimal-delta-v solution. specific kinetic energy at launch = μ R − μ major axis = μ R sin θ 1 + sin θ {\displaystyle {\text{specific kinetic energy at launch}}={\frac {\mu }{R}}-{\frac {\mu }{\text{major axis}}}={\frac {\mu }{R}}{\frac {\sin \theta }{1+\sin \theta }}} Δ v = speed at launch = 2 μ R sin θ 1 + sin θ = 2 g R sin θ 1 + sin θ {\displaystyle \Delta v={\text{speed at launch}}={\sqrt {2{\frac {\mu }{R}}{\frac {\sin \theta }{1+\sin \theta }}}}={\sqrt {2gR{\frac {\sin \theta }{1+\sin \theta }}}}} (where g
2444-425: Is similar to an ICBM. ICBMs have delta-v's somewhat less than orbital; and therefore would be somewhat cheaper than the costs for reaching orbit, but the difference is not large. Due to the high cost of spaceflight, suborbital flights are likely to be initially limited to high value, very high urgency cargo deliveries such as courier flights, military fast-response operations or space tourism . The SpaceLiner
2538-412: Is the standard gravitational parameter . Almost always a < R , corresponding to a lower ϵ {\displaystyle \epsilon } than the minimum for a full orbit, which is − μ 2 R {\displaystyle -{\mu \over {2R}}\,\!} Thus the net extra specific energy needed compared to just raising the spacecraft into space
2632-447: Is the acceleration of gravity at the Earth's surface). The Δ v increases with range, leveling off at 7.9 km/s as the range approaches 20 000 km (halfway around the world). The minimum-delta-v trajectory for going halfway around the world corresponds to a circular orbit just above the surface (of course in reality it would have to be above the atmosphere). See lower for the time of flight. An intercontinental ballistic missile
2726-441: The g -force experienced by the astronauts, permitted a reasonable amount of directional control and allowed the capsule's splashdown point to be targeted within a few miles. At 24,000 feet (7,300 m), the forward heat shield was jettisoned using four pressurized-gas compression springs. The drogue parachutes were then deployed, slowing the spacecraft to 125 miles per hour (201 kilometres per hour). At 10,700 feet (3,300 m)
2820-515: The Aerojet-General company to start developing the engine, resulting in a thrust level twice what was needed to accomplish the lunar orbit rendezvous (LOR) mission mode officially chosen in July of that year. The engine was actually used for mid-course corrections between the Earth and Moon, and to place the spacecraft into and out of lunar orbit. It also served as a retrorocket to perform
2914-554: The Fractional Orbital Bombardment System . A flight that does not reach space is still sometimes called sub-orbital, but cannot officially be classified as a "sub-orbital spaceflight". Usually a rocket is used, but some experimental sub-orbital spaceflights have also been achieved via the use of space guns . By definition, a sub-orbital spaceflight reaches an altitude higher than 100 km (62 mi) above sea level . This altitude, known as
Command module - Misplaced Pages Continue
3008-461: The V-2 rocket , just reaching space but with a range of about 330 km, the maximum speed was 1.6 km/s. Scaled Composites SpaceShipTwo which is under development will have a similar free-fall orbit but the announced maximum speed is 1.1 km/s (perhaps because of engine shut-off at a higher altitude). For larger ranges, due to the elliptic orbit the maximum altitude can be much more than for
3102-656: The Virgin Group announced the creation of Virgin Galactic and his plans for a 9-seat capacity SpaceShipTwo named VSS Enterprise . It has since been completed with eight seats (one pilot, one co-pilot and six passengers) and has taken part in captive-carry tests and with the first mother-ship WhiteKnightTwo , or VMS Eve . It has also completed solitary glides, with the movable tail sections in both fixed and "feathered" configurations. The hybrid rocket motor has been fired multiple times in ground-based test stands, and
3196-464: The flight phases before and after the free-fall can vary. For an intercontinental flight the boost phase takes 3 to 5 minutes, the free-fall (midcourse phase) about 25 minutes. For an ICBM the atmospheric reentry phase takes about 2 minutes; this will be longer for any soft landing, such as for a possible future commercial flight. Test flight 4 of the SpaceX 'Starship' performed such a flight with
3290-466: The fuel cell gauges and controls, the electrical and battery controls, and the communications controls. Flanking the sides of the main panel were sets of smaller control panels. On the left side were a circuit breaker panel, audio controls, and the SCS power controls. On the right were additional circuit breakers and a redundant audio control panel, along with the environmental control switches. In total,
3384-452: The transposition, docking, and extraction maneuver at the beginning of the translunar coast. The docking mechanism was a non-androgynous system, consisting of a probe located in the nose of the CSM, which connected to the drogue , a truncated cone located on the lunar module. The probe was extended like a scissor jack to capture the drogue on initial contact, known as soft docking . Then
3478-700: The Block I service module propellant tanks were slightly larger than in Block II. The Apollo 1 spacecraft weighed approximately 45,000 pounds (20,000 kg), while the Block II Apollo 7 weighed 36,400 lb (16,500 kg). (These two Earth orbital craft were lighter than the craft which later went to the Moon, as they carried propellant in only one set of tanks, and did not carry the high-gain S-band antenna.) In
3572-521: The CM and faster break-up on re-entry. The service propulsion system ( SPS ) engine was originally designed to lift the CSM off the surface of the Moon in the direct ascent mission mode, The engine selected was the AJ10-137 , which used Aerozine 50 as fuel and nitrogen tetroxide (N 2 O 4 ) as oxidizer to produce 20,500 lbf (91 kN) of thrust. A contract was signed in April 1962 for
3666-472: The CM reaction control subsystem; water tanks; the crushable ribs of the impact attenuation system; and a number of instruments. The CM-SM umbilical, the point where wiring and plumbing ran from one module to the other, was also in the aft compartment. The panels of the heat shield covering the aft compartment were removable for maintenance of the equipment before flight. The components of the ELS were housed around
3760-533: The CSM umbilical cables . The command module was built in North American's factory in Downey, California , and consisted of two basic structures joined together: the inner structure (pressure shell) and the outer structure. The inner structure was an aluminum sandwich construction consisting of a welded aluminum inner skin, adhesively bonded aluminum honeycomb core, and outer face sheet. The thickness of
3854-458: The Earth's atmosphere. At jettison, the CM umbilical connections were cut using a pyrotechnic-activated guillotine assembly. Following jettison, the SM aft translation thrusters automatically fired continuously to distance it from the CM, until either the RCS fuel or the fuel cell power was depleted. The roll thrusters were also fired for five seconds to make sure it followed a different trajectory from
Command module - Misplaced Pages Continue
3948-609: The Kármán line, was chosen by the Fédération Aéronautique Internationale because it is roughly the point where a vehicle flying fast enough to support itself with aerodynamic lift from the Earth's atmosphere would be flying faster than orbital speed . The US military and NASA award astronaut wings to those flying above 50 mi (80 km), although the U.S. State Department does not show
4042-467: The Moon atop a landing rocket stage and return all three astronauts on a direct-ascent mission, which would not use a separate lunar module, and thus had no provisions for docking with another spacecraft. This, plus other required design changes, led to the decision to design two versions of the CSM: Block I was to be used for uncrewed missions and a single crewed Earth orbit flight ( Apollo 1 ), while
4136-436: The Moon between 1968 and 1972, and another two performed crewed test flights in low Earth orbit , all as part of the Apollo program. Before these, another four CSMs had flown as uncrewed Apollo tests, of which two were suborbital flights and another two were orbital flights . Following the conclusion of the Apollo program and during 1973–1974, three CSMs ferried astronauts to the orbital Skylab space station. Finally in 1975,
4230-406: The altitude required to qualify as reaching space. The flight path will be either vertical or very steep, with the spacecraft landing back at its take-off site. The spacecraft will shut off its engines well before reaching maximum altitude, and then coast up to its highest point. During a few minutes, from the point when the engines are shut off to the point where the atmosphere begins to slow down
4324-402: The angle that the projectile is to go around the Earth, so in degrees it is 45°× d / 10 000 km . The minimum-delta-v trajectory corresponds to an ellipse with one focus at the centre of the Earth and the other at the point halfway between the launch point and the destination point (somewhere inside the Earth). (This is the orbit that minimizes the semi-major axis, which is equal to the sum of
4418-569: The base, and a height of 11 feet 5 inches (3.48 m) including the docking probe and dish-shaped aft heat shield. The forward compartment contained two reaction control system thrusters, the docking tunnel, and the Earth Landing System. The inner pressure vessel housed the crew accommodation, equipment bays, controls and displays, and many spacecraft systems. The aft compartment contained 10 reaction control engines and their related propellant tanks, freshwater tanks, and
4512-506: The center piston. In a temperature degraded condition, a single motor release operation was done manually in the lunar module by depressing the locking spool through an open hole in the probe heads, while release from the CSM was done by rotating a release handle at the back of the probe to rotate the motor torque shaft manually. When the command and lunar modules separated for the last time, the probe and forward docking ring were pyrotechnically separated, leaving all docking equipment attached to
4606-451: The command module panels included 24 instruments, 566 switches, 40 event indicators, and 71 lights. The three crew couches were constructed from hollow steel tubing and covered in a heavy, fireproof cloth known as Armalon. The leg pans of the two outer couches could be folded in a variety of positions, while the hip pan of the center couch could be disconnected and laid on the aft bulkhead. One rotation and one translation hand controller
4700-409: The deorbit burn for Earth orbital flights. The propellants were pressure-fed to the engine by 39.2 cubic feet (1.11 m ) of gaseous helium at 3,600 pounds per square inch (25 MPa), carried in two 40-inch (1.0 m) diameter spherical tanks. The exhaust nozzle measured 152.82 inches (3.882 m) long and 98.48 inches (2.501 m) wide at the base. It was mounted on two gimbals to keep
4794-473: The destination point (which is below the horizon). Again, this is the case if the Earth's rotation is ignored. It is not exactly true for a rotating planet unless the launch takes place at a pole. In a vertical flight of not too high altitudes, the time of the free-fall is both for the upward and for the downward part the maximum speed divided by the acceleration of gravity , so with a maximum speed of 1 km/s together 3 minutes and 20 seconds. The duration of
SECTION 50
#17327803233244888-1764: The distances from a point on the orbit to the two foci. Minimizing the semi-major axis minimizes the specific orbital energy and thus the delta-v, which is the speed of launch.) Geometrical arguments lead then to the following (with R being the radius of the Earth, about 6370 km): major axis = ( 1 + sin θ ) R {\displaystyle {\text{major axis}}=(1+\sin \theta )R} minor axis = R 2 ( sin θ + sin 2 θ ) = R sin ( θ ) semi-major axis {\displaystyle {\text{minor axis}}=R{\sqrt {2\left(\sin \theta +\sin ^{2}\theta \right)}}={\sqrt {R\sin(\theta ){\text{semi-major axis}}}}} distance of apogee from centre of Earth = R 2 ( 1 + sin θ + cos θ ) {\displaystyle {\text{distance of apogee from centre of Earth}}={\frac {R}{2}}(1+\sin \theta +\cos \theta )} altitude of apogee above surface = ( sin θ 2 − sin 2 θ 2 ) R = ( 1 2 sin ( θ + π 4 ) − 1 2 ) R {\displaystyle {\text{altitude of apogee above surface}}=\left({\frac {\sin \theta }{2}}-\sin ^{2}{\frac {\theta }{2}}\right)R=\left({\frac {1}{\sqrt {2}}}\sin \left(\theta +{\frac {\pi }{4}}\right)-{\frac {1}{2}}\right)R} The altitude of apogee
4982-572: The downward acceleration, the passengers will experience weightlessness . Megaroc had been planned for sub-orbital spaceflight by the British Interplanetary Society in the 1940s. In late 1945, a group led by M. Tikhonravov K. and N. G. Chernysheva at the Soviet NII-4 academy (dedicated to rocket artillery science and technology), began work on a stratospheric rocket project, VR-190 , aimed at vertical flight by
5076-441: The drogues were jettisoned and the pilot parachutes, which pulled out the mains, were deployed. These slowed the CM to 22 miles per hour (35 kilometres per hour) for splashdown. The portion of the capsule that first contacted the water surface contained four crushable ribs to further mitigate the force of impact. The command module could safely parachute to an ocean landing with only two parachutes deployed (as occurred on Apollo 15 ),
5170-491: The environmental control system). On the flight of Apollo 13 , the EPS was disabled by an explosive rupture of one oxygen tank, which punctured the second tank and led to the loss of all oxygen. After the accident, a third oxygen tank was added to obviate operation below 50% tank capacity. That allowed the elimination of the tank's internal stirring-fan equipment, which had contributed to the failure. Also starting with Apollo 14 ,
5264-498: The equator.) For sub-orbital spaceflights covering a horizontal distance the maximum speed and required delta-v are in between those of a vertical flight and a LEO. The maximum speed at the lower ends of the trajectory are now composed of a horizontal and a vertical component. The higher the horizontal distance covered, the greater the horizontal speed will be. (The vertical velocity will increase with distance for short distances but will decrease with distance at longer distances.) For
5358-431: The forward docking tunnel. The forward compartment was separated from the central by a bulkhead and was divided into four 90-degree wedges. The ELS consisted of two drogue parachutes with mortars , three main parachutes , three pilot parachutes to deploy the mains, three inflation bags for uprighting the capsule if necessary, a sea recovery cable, a dye marker, and a swimmer umbilical. The command module's center of mass
5452-415: The forward heat shield was jettisoned to expose the Earth landing equipment and permit deployment of the parachutes. The 1-foot-8-inch (0.51 m)-tall aft compartment was located around the periphery of the command module at its widest part, just forward of (above) the aft heat shield. The compartment was divided into 24 bays containing 10 reaction control engines; the fuel, oxidizer, and helium tanks for
5546-404: The honeycomb varied from about 1.5 inches (3.8 cm) at the base to about 0.25 inches (0.64 cm) at the forward access tunnel. This inner structure was the pressurized crew compartment. The outer structure was made of stainless steel brazed-honeycomb brazed between steel alloy face sheets. It varied in thickness from 0.5 inch to 2.5 inches. Part of the area between the inner and outer shells
5640-452: The inside of an 8-by-2.75-foot (2.44 by 0.84 m) skin panel. The primary fuel (MMH) tank contained 69.1 pounds (31.3 kg); the secondary fuel tank contained 45.2 pounds (20.5 kg); the primary oxidizer tank contained 137.0 pounds (62.1 kg), and the secondary oxidizer tank contained 89.2 pounds (40.5 kg). The propellant tanks were pressurized from a single tank containing 1.35 pounds (0.61 kg) of liquid helium. Back flow
5734-510: The last flown CSM docked with the Soviet craft Soyuz 19 as part of the international Apollo–Soyuz Test Project . Concepts of an advanced crewed spacecraft started before the Moon landing goal was announced. The three-person vehicle was to be mainly for orbital use around Earth. It would include a large pressurized auxiliary orbital module where the crew would live and work for weeks at a time. They would perform space station-type activities in
SECTION 60
#17327803233245828-475: The length of the minimum-delta-v trajectory will be about 19 500 km , but it will take only a few seconds less time than the trajectory for d = 20 000 km (for which the trajectory is 20 000 km long). While there are a great many possible sub-orbital flight profiles, it is expected that some will be more common than others. The first sub-orbital vehicles which reached space were ballistic missiles . The first ballistic missile to reach space
5922-461: The lunar module. In the event of an abort during launch from Earth, the same system would have explosively jettisoned the docking ring and probe from the CM as it separated from the boost protective cover. The central pressure vessel of the command module was its sole habitable compartment. It had an interior volume of 210 cubic feet (5.9 m ) and housed the main control panels, crew seats, guidance and navigation systems, food and equipment lockers,
6016-478: The market, from a variety of suppliers in various countries. Typically, researchers wish to conduct experiments in microgravity or above the atmosphere. Research, such as that done for the X-20 Dyna-Soar project suggests that a semi-ballistic sub-orbital flight could travel from Europe to North America in less than an hour. However, the size of rocket, relative to the payload, necessary to achieve this,
6110-445: The maximum speed of the flight. The aerodynamic heating caused will vary accordingly: it is much less for a flight with a maximum speed of only 1 km/s than for one with a maximum speed of 7 or 8 km/s. The minimum delta-v and the corresponding maximum altitude for a given range can be calculated, d , assuming a spherical Earth of circumference 40 000 km and neglecting the Earth's rotation and atmosphere. Let θ be half
6204-470: The module's pressure vessel. The fused silica outer pane served as both a debris shield and as part of the heat shield. Each pane had an anti-reflective coating and a blue-red reflective coating on the inner surface. Sources: The service module was an unpressurized cylindrical structure with a diameter of 12 feet 10 inches (3.91 m) and 14 feet 10 inches (4.52 m) long. The service propulsion engine nozzle and heat shield increased
6298-500: The module, while later versions would use the module to carry cargo to space stations. The spacecraft was to service the Project Olympus (LORL), a foldable rotating space station launched on a single Saturn V . Later versions would be used on circumlunar flights, and would be the basis for a direct ascent lunar spacecraft as well as used on interplanetary missions. In late 1960, NASA called on U.S. industry to propose designs for
6392-415: The more advanced Block II was designed for use with the lunar module. The Apollo 1 flight was cancelled after a cabin fire killed the crew and destroyed their command module during a launch rehearsal test. Corrections of the problems which caused the fire were applied to the Block II spacecraft, which was used for all crewed spaceflights. Nineteen CSMs were launched into space. Of these, nine flew humans to
6486-1946: The portion of the area of the ellipse swept by the line from the centre of the Earth to the projectile: area fraction = 1 π arcsin 2 sin θ 1 + sin θ + 2 cos θ sin θ π (major axis)(minor axis) {\displaystyle {\text{area fraction}}={\frac {1}{\pi }}\arcsin {\sqrt {\frac {2\sin \theta }{1+\sin \theta }}}+{\frac {2\cos \theta \sin \theta }{\pi {\text{(major axis)(minor axis)}}}}} time of flight = ( ( 1 + sin θ 2 ) 3 2 arcsin 2 sin θ 1 + sin θ + 1 2 cos θ sin θ ) 2 R g = ( ( 1 + sin θ 2 ) 3 2 arccos cos θ 1 + sin θ + 1 2 cos θ sin θ ) 2 R g {\displaystyle {\begin{aligned}{\text{time of flight}}&=\left(\left({\frac {1+\sin \theta }{2}}\right)^{\frac {3}{2}}\arcsin {\sqrt {\frac {2\sin \theta }{1+\sin \theta }}}+{\frac {1}{2}}\cos \theta {\sqrt {\sin \theta }}\right)2{\sqrt {\frac {R}{g}}}\\&=\left(\left({\frac {1+\sin \theta }{2}}\right)^{\frac {3}{2}}\arccos {\frac {\cos \theta }{1+\sin \theta }}+{\frac {1}{2}}\cos \theta {\sqrt {\sin \theta }}\right)2{\sqrt {\frac {R}{g}}}\\\end{aligned}}} This gives about 32 minutes for going
6580-419: The pressure between the tunnel and the CM so the hatch could be removed. The unified crew hatch (UCH) measured 29 inches (74 cm) high, 34 inches (86 cm) wide, and weighed 225 pounds (102 kg). It was operated by a pump handle, which drove a ratchet mechanism to open or close fifteen latches simultaneously. Apollo's mission required the LM to dock with the CSM on return from the Moon, and also in
6674-637: The primary flight controls, and the main FDAI (Flight Director Attitude Indicator). The CM pilot served as navigator, so his control panel (center) included the Guidance and Navigation computer controls, the caution and warning indicator panel, the event timer, the Service Propulsion System and RCS controls, and the environmental control system controls. The LM pilot served as systems engineer, so his control panel (right-hand side) included
6768-471: The probe cylinder body engaged and retained the probe center piston in the retracted position. Before vehicle separation in lunar orbit, manual cocking of the twelve ring latches was accomplished. The separating force from the internal pressure in the tunnel area was then transmitted from the ring latches to the probe and drogue. In undocking, the release of the capture latches was accomplished by electrically energizing tandem-mounted DC rotary solenoids located in
6862-412: The probe was retracted to pull the vehicles together and establish a firm connection, known as "hard docking". The mechanism was specified by NASA to have the following functions: The probe head located in the CSM was self-centering and gimbal-mounted to the probe piston. As the probe head engaged in the opening of the drogue socket, three spring-loaded latches depressed and engaged. These latches allowed
6956-488: The reaction control system (RCS) computer, power distribution block, ECS controller, separation controller, and components for the high-gain antenna, and included eight EPS radiators and the umbilical connection arm containing the main electrical and plumbing connections to the CM. The fairing externally contained a retractable forward-facing spotlight ; an EVA floodlight to aid the command module pilot in SIM film retrieval; and
7050-524: The specifications given below, unless otherwise noted, all weights given are for the Block II spacecraft. The total cost of the CSM for development and the units produced was $ 36.9 billion in 2016 dollars, adjusted from a nominal total of $ 3.7 billion using the NASA New Start Inflation Indices. The command module was a truncated cone ( frustum ) with a diameter of 12 feet 10 inches (3.91 m) across
7144-543: The third parachute being a safety precaution. The command module attitude control system consisted of twelve 93-pound-force (410 N) attitude control thrusters, ten of which were located in the aft compartment, plus two in the forward compartment. These were supplied by four tanks storing 270 pounds (120 kg) of monomethylhydrazine fuel and nitrogen tetroxide oxidizer, and pressurized by 1.1 pounds (0.50 kg) of helium stored at 4,150 pounds per square inch (28.6 MPa) in two tanks. The forward docking hatch
7238-787: The thrust vector aligned with the spacecraft's center of mass during SPS firings. The combustion chamber and pressurant tanks were housed in the central tunnel. Four clusters of four reaction control system (RCS) thrusters (known as "quads") were installed around the upper section of the SM every 90°. The sixteen-thruster arrangement provided rotation and translation control in all three spacecraft axes. Each R-4D thruster measured 12 inches (30 cm) long by 6 inches (15 cm) diameter, generated 100 pounds-force (440 N) of thrust, and used helium-fed monomethylhydrazine (MMH) as fuel and nitrogen tetroxide (NTO) as oxidizer. Each quad assembly measured 2.2 by 2.7 feet (0.67 by 0.82 m) and had its own fuel, oxidizer, and helium tanks mounted on
7332-556: The time. After a thorough investigation by the Apollo 204 Review Board, it was decided to terminate the crewed Block I phase and redefine Block II to incorporate the review board's recommendations . Block II incorporated a revised CM heat shield design, which was tested on the uncrewed Apollo 4 and Apollo 6 flights, so the first all-up Block II spacecraft flew on the first crewed mission, Apollo 7 . The two blocks were essentially similar in overall dimensions, but several design improvements resulted in weight reduction in Block II. Also,
7426-575: The total height to 24 feet 7 inches (7.49 m). The interior was a simple structure consisting of a central tunnel section 44 inches (1.1 m) in diameter, surrounded by six pie-shaped sectors. The sectors were topped by a forward bulkhead and fairing, separated by six radial beams, covered on the outside by four honeycomb panels, and supported by an aft bulkhead and engine heat shield. The sectors were not all equal 60° angles, but varied according to required size. The forward fairing measured 1 foot 11 inches (58 cm) long and housed
7520-411: The upper end of the lunar module tunnel, the drogue, which was constructed of 1-inch-thick aluminum honeycomb core, bonded front and back to aluminum face sheets, was the receiving end of the probe head capture latches. After the initial capture and stabilization of the vehicles, the probe was capable of exerting a closing force of 1,000 pounds-force (4.4 kN) to draw the vehicles together. This force
7614-421: The vehicle. On May 25, 1961 President John F. Kennedy announced the Moon landing goal before 1970, which immediately rendered NASA's Olympus Station plans obsolete. When NASA awarded the initial Apollo contract to North American Aviation on November 28, 1961, it was still assumed the lunar landing would be achieved by direct ascent rather than by lunar orbit rendezvous . Therefore, design proceeded without
7708-402: The waste management system, and the docking tunnel. Dominating the forward section of the cabin was the crescent-shaped main display panel measuring nearly 7 feet (2.1 m) wide and 3 feet (0.91 m) tall. It was arranged into three panels, each emphasizing the duties of each crew member. The mission commander's panel (left side) included the velocity , attitude, and altitude indicators,
7802-451: Was filled with a layer of fiberglass insulation as additional heat protection. An ablative heat shield on the outside of the CM protected the capsule from the heat of reentry , which is sufficient to melt most metals. This heat shield was composed of phenolic formaldehyde resin . During reentry, this material charred and melted away, absorbing and carrying away the intense heat in the process. The heat shield has several outer coverings:
7896-492: Was fired in a powered flight for the second time on 5 September 2013. Four additional SpaceShipTwos have been ordered and will operate from the new Spaceport America . Commercial flights carrying passengers were expected in 2014, but became cancelled due to the disaster during SS2 PF04 flight . Branson stated, "[w]e are going to learn from what went wrong, discover how we can improve safety and performance and then move forwards together." A major use of sub-orbital vehicles today
7990-451: Was generated by gas pressure acting on the center piston within the probe cylinder. Piston retraction compressed the probe and interface seals and actuated the 12 automatic ring latches which were located radially around the inner surface of the CSM docking ring. The latches were manually re-cocked in the docking tunnel by an astronaut after each hard docking event (lunar missions required two dockings). An automatic extension latch attached to
8084-529: Was installed on the armrests of the left-hand couch. The translation controller was used by the crew member performing the transposition, docking, and extraction maneuver with the LM, usually the CM Pilot. The center and right-hand couches had duplicate rotational controllers. The couches were supported by eight shock-attenuating struts, designed to ease the impact of touchdown on water or, in case of an emergency landing, on solid ground. The contiguous cabin space
8178-431: Was mounted at the top of the docking tunnel. It was 30 inches (76 cm) in diameter and weighed 80 pounds (36 kg), constructed from two machined rings that were weld-joined to a brazed honeycomb panel. The exterior side was covered with 0.5-inch (13 mm) of insulation and a layer of aluminum foil. It was latched in six places and operated by a pump handle. The hatch contained a valve in its center, used to equalize
8272-410: Was offset a foot or so from the center of pressure (along the symmetry axis). This provided a rotational moment during reentry, angling the capsule and providing some lift (a lift to drag ratio of about 0.368 ). The capsule was then steered by rotating the capsule using thrusters; when no steering was required, the capsule was spun slowly, and the lift effects cancelled out. This system greatly reduced
8366-551: Was organized into six equipment bays: The CM had five windows. The two side windows measured 9 inches (23 cm) square next to the left and right-hand couches. Two forward-facing triangular rendezvous windows measured 8 by 9 inches (20 by 23 cm), used to aid in rendezvous and docking with the LM. The circular hatch window was 9 inches (23 cm) in diameter located directly over the center couch. Each window assembly consisted of three thick panes of glass. The inner two panes, which were made of aluminosilicate , made up part of
8460-530: Was prevented by a series of check valves, and back flow and ullage requirements were resolved by containing the fuel and oxidizer in Teflon bladders which separated the propellants from the helium pressurant. The four completely independent RCS clusters provided redundancy; only two adjacent functioning units were needed to allow complete attitude control. The lunar module used a similar four-quad arrangement of R-4D thruster engines for its RCS. Electrical power
8554-552: Was produced by three fuel cells , each measuring 44 inches (1.1 m) tall by 22 inches (0.56 m) in diameter and weighing 245 pounds (111 kg). These combined hydrogen and oxygen to generate electrical power, and produced drinkable water as a byproduct. The cells were fed by two hemispherical-cylindrical 31.75-inch (0.806 m) diameter tanks, each holding 29 pounds (13 kg) of liquid hydrogen , and two spherical 26-inch (0.66 m) diameter tanks, each holding 326 pounds (148 kg) of liquid oxygen (which also supplied
8648-469: Was reduced to one in late 1966. This mission, designated AS-204 but named Apollo 1 by its flight crew, was planned for launch on February 21, 1967. During a dress rehearsal for the launch on January 27, all three astronauts ( Gus Grissom , Ed White and Roger Chaffee ) were killed in a cabin fire, which revealed serious design, construction and maintenance shortcomings in Block I, many of which had been carried over into Block II command modules being built at
8742-688: Was the German V-2 , the work of the scientists at Peenemünde , on October 3, 1942, which reached an altitude of 53 miles (85 km). Then in the late 1940s the US and USSR concurrently developed missiles all of which were based on the V-2 Rocket, and then much longer range Intercontinental Ballistic Missiles (ICBMs). There are now many countries who possess ICBMs and even more with shorter range Intermediate Range Ballistic Missiles (IRBMs). Sub-orbital tourist flights will initially focus on attaining
8836-466: Was the area outside the inner pressure shell in the nose of the capsule, located around the forward docking tunnel and covered by the forward heat shield. The compartment was divided into four 90-degree segments that contained Earth landing equipment (all the parachutes, recovery antennas and beacon light, and sea recovery sling), two reaction control thrusters, and the forward heat shield release mechanism. At about 25,000 feet (7,600 m) during reentry,
#323676