Apollo 7 (October 11-22, 1968) was the first manned mission in the Apollo program to be launched. It was an eleven-day Earth-orbital mission, the first manned launch of the Saturn IB launch vehicle, and the first three-person American space mission. The flight was an open-ended flight which meant that the mission would continue as long as it was safe and there were enough consumables on board, including oxygen. It flew low around the earth so it could track life-support systems, the propulsion systems and the control systems.
Apollo 7 was a test flight, and confidence-builder. After the January 1967 Apollo launch pad fire, the Apollo command module had been extensively redesigned. Schirra, who would be the only astronaut to fly Mercury, Gemini and Apollo missions, commanded this Earth-orbital shakedown of the command and service modules. Since it was not carrying a lunar module, Apollo 7 could be launched with the Saturn IB booster rather than the much larger and more powerful Saturn V. Schirra wanted to give Apollo 7 the callsign "Phoenix" (the mythical bird rising from its own ashes) in memory of the loss of the Apollo 1 crew, but NASA management was against the idea.
The Apollo hardware and all mission operations worked without any significant problems, and the Service Propulsion System (SPS), the all-important engine that would place Apollo in and out of lunar orbit, made eight nearly perfect firings.
Even though Apollo's larger cabin was more comfortable than Gemini's, eleven days in orbit took its toll on the astronauts. Tension with Commander Schirra began with the launch decision, when flight managers decided to launch with a less than ideal abort option for the early part of the ascent. Once in orbit, the spacious cabin may have induced some crew motion sickness, which had not been an issue in the earlier, smaller spacecraft. The crew also found the food to be bad. But the worst problem occurred when Schirra developed a bad head cold. As a result, he became irritable with requests from Mission Control and all three began "talking back" to the Capcom. An early example was this exchange after Mission Control requested that a TV camera be turned on in the spacecraft:
SCHIRRA: You've added two burns to this flight schedule, and you've added a urine water dump; and we have a new vehicle up here, and I can tell you this point TV will be delayed without any further discussion until after the rendezvous.CAPCOM: Roger. Copy.SCHIRRA: Roger.CAPCOM: Apollo 7 This is CAP COM number 1.SCHIRRA: Roger.CAPCOM: All we've agreed to do on this is flip it.SCHIRRA: ... with two commanders, Apollo 7CAPCOM: All we have agreed to on this particular pass is to flip the switch on. No other activity is associated with TV; I think we are still obligated to do that.SCHIRRA: We do not have the equipment out; we have not had an opportunity to follow setting; we have not eaten at this point. At this point, I have a cold. I refuse to foul up our time lines this way.
Exchanges such as this would lead to the crew members being passed over for future missions. But the mission successfully proved the space-worthiness of the basic Apollo vehicle, and led directly to the bold decision to launch Apollo 8 to the moon two months later.
Beyond a shakedown of the spacecraft, goals for the mission included the first live television broadcast from an American spacecraft (Gordon Cooper had broadcast slow scan television pictures from Faith 7 in 1963) and testing the lunar module docking maneuver with the launch vehicle's discarded upper stage.
First orbit: perigee 231 km, apogee 297 km, period 89.78 min, inclination 31.63 deg., weight: CSM 14,781 kg.
The splashdown point was 27 deg 32 min N, 64 deg 04 min W, 200 nautical miles (370 km) SSW of Bermuda and 13 km (8.1 mi) north of the recovery ship USS Essex.
Apollo 7 was the only manned Apollo launch to take place from Cape Canaveral Air Force Station's Launch Complex 34, as all subsequent Apollo (including Apollo-Soyuz) and Skylab missions were launched from Launch Complex 39 at the nearby Kennedy Space Center.
As of 2009, Cunningham is the only surviving member of the crew. Eisele died in 1987 and Schirra in 2007.
In October 2008, NASA administrator Michael D.Griffin awarded the crew of Apollo 7 NASA's Distinguished Service Medal, in recognition of their crucial contribution to the Apollo Program. They had been the only Apollo and Skylab crew not granted this award. Cunningham was present to accept the medal, as were representatives of his deceased crew members, and other Apollo astronauts including Neil Armstrong, Bill Anders, and Alan Bean. Former Mission Control Flight Director Chris Kraft, who was in conflict with the crew during the mission, also sent a conciliatory video message of congratulations, saying: "We gave you a hard time once but you certainly survived that and have done extremely well since...I am frankly, very proud to call you a friend."
The insignia for the flight showed a command and service module with its SPS engine firing, the trail from that fire encircling a globe and extending past the edges of the patch symbolizing the Earth-orbital nature of the mission. The Roman numeral VII appears in the South Pacific Ocean and the crew's names appear on a wide black arc at the bottom. The patch was designed by Allen Stevens of Rockwell International.
In January 1969, the Apollo 7 command module was displayed on a NASA float in the inauguration parade of President Richard M.Nixon. For nearly 30 years the command module was on loan (renewable every two years) to the National Museum of Science and Technology of Canada, in Ottawa, along with the space suit worn by Wally Schirra. In November 2003 the Smithsonian Institution in Washington D.C. requested them back for display at their new annex at the Steven F.Udvar-Hazy Centrer. Currently, the Apollo 7 CM is on loan to the Frontiers of Flight Museum located next to Love Field in Dallas, Texas.
Wednesday 9 December 2009
Apollo 6
Apollo 6, launched on April 4, 1968, was the Apollo program's second and last unmanned test flight of its Saturn V launch vehicle.
This was the final qualification flight of the Saturn V before its first manned flight (Apollo 8) (While Apollo 7 was the first manned Apollo mission, it used the smaller Saturn IB, not the Saturn V.) It was also the first mission to use High Bay 3 in the Vertical Assembly Building (VAB), Mobile Launcher 2 and Firing Room 2. Another objective was testing the Command Module re-entry system under extreme conditions simulating a worst-case return from the Moon. This objective was not met due to J-2 engine failures.
The S-IC first stage arrived by barge on March 13, 1967 and was erected in the VAB four days later, with the S-IVB third stage and Instrument Unit computer arriving the same day. The S-II second stage was two months behind them and so was substituted with a dumbbell shaped spacer so testing could proceed. This had the same height and mass as the S-II along with all the electrical connections. The S-II arrived May 24. It was stacked and mated into the rocket on July 7.
Testing was slow as they were still checking out the launch vehicle for Apollo 4, a limitation of the system where there wasn't two of everyone and everything. The VAB could handle up to four Saturn Vs but could only check out one at a time.
The Command and Service Module arrived September 29 and was stacked December 10. It was a hybrid, featuring the Command Module Number 20 and Service Module Number 14 after SM-020 was destroyed in a tank explosion and Command Module Number 14 was dismantled as part of the investigation into the Apollo 1 fire. After two months of testing and repairs the rocket was moved to the pad on February 6, 1968.
Unlike the near perfect flight of Apollo 4, Apollo 6 experienced problems right from the start. Two minutes into the flight, the rocket experienced severe pogo oscillations for about 30 seconds. George Mueller explained the cause to a congressional hearing:
Pogo arises fundamentally because you have thrust fluctuations in the engines. Those are normal characteristics of engines. All engines have what you might call noise in their output because the combustion is not quite uniform, so you have this fluctuation in thrust of the first stage as a normal characteristic of all engine burning.
Now, in turn, the engine is fed through a pipe that takes the fuel out of the tanks and feeds it into the engine. That pipe's length is something like an organ pipe so it has a certain resonance frequency of its own and it really turns out that it will oscillate just like an organ pipe does.
The structure of the vehicle is much like a tuning fork, so if you strike it right, it will oscillate up and down longitudinally. In a gross sense it is the interaction between the various frequencies that causes the vehicle to oscillate.
In part due to the pogo, the spacecraft adaptor that attached the CSM and mockup of the Lunar Module to the rocket started to have some structural problems. Airborne cameras recorded several pieces falling off it at T+133s.
After the first stage was jettisoned at the end of its task, the S-II second stage began to experience its own problems. Engine number two (of five) had performance problems from 206 to 319 seconds after liftoff and then at 412 seconds shut down altogether. Then two seconds later Engine Number Three shut down as well. The onboard computer was able to compensate and the stage burned for 58 seconds more than normal. Even so the S-IVB third stage also had to burn for 29 seconds longer than usual.
The S-IC first stage impacted the Atlantic Ocean east of Florida , while the S-II second stage impacted south of the Azores.
Due to the less than nominal launch, the CSM and S-IVB were now in a 178 by 367 km orbit instead of the planned 160 km circular orbit. But after two orbits of checking out the spacecraft and rocket stage the S-IVB failed to restart to simulate the Trans Lunar Injection burn that would send the astronauts to the moon.
It was decided to use the Service Module engine to raise the spacecraft into a high orbit in order to complete some of the mission objectives. It burned for 442 seconds, longer than it would ever have to on a real Apollo mission and raised the apogee of the orbit to 22,200 km. There was now however not enough fuel to speed up the atmospheric reentry and the spacecraft only entered the atmosphere at a speed of 10,000 m/s instead of the planned 11,270 m/s. This meant it landed 80 km from the planned touch down point.
Ten hours after launch it was lifted on board the USS Okinawa.
S-IVB reentered on April 25, 1968.
The cause of the pogo during the first stage of the flight was well known. However, it had been thought that the rocket had been 'detuned'. To further dampen pressure oscillations in the fuel and oxidzer pumps and feed lines, cavities in these systems were filled with helium gas from the propulsion system's pneumatic control system, which acted to attenuate the oscillations.
The failure of the two engines in the second stage was traced to the rupturing of a fuel line that fed the engine igniters. The igniter was essentially a miniature rocket motor mounted in the wall of the J-2 engine's pressure chamber. It was fed by small-diameter flexible lines carrying liquid hydrogen and liquid oxygen. During the S-II second stage burn, the hydrogen line feeding the engine number three igniter broke due to vibration. As a result, the igniter fed pure liquid oxygen into the pressure chamber. Normally the J-2 engine burns a hydrogen-rich mixture to keep temperature down. The liquid oxygen flow caused a much higher temperature locally and eventually the pressure chamber failed. The sudden drop in pressure was detected and caused a shutdown command to be issued. Unfortunately, the shutdown command signal for engine three was cross-wired to engine two. Engine two shut down and in turn its pressure sensor sent a shutdown signal back to engine three.
The problem in the igniter fuel lines was not detected during ground testing because a stainless steel mesh covering the fuel line became saturated with liquid air due to the extreme cold of the liquid hydrogen flowing through it. The liquid air damped a vibration mode that became evident when tests were conducted in a vacuum after the Apollo 6 flight. This was also a simple fix, involving replacing the flexible bellows section where the break occurred with a loop of stainless steel pipe. The S-IVB used the same J-2 engine design as the S-II and so it was decided that an igniter line problem had also stopped the third stage from reigniting in Earth orbit.
The spacecraft adapter problem was caused by its honeycomb structure. As the rocket accelerated through the atmosphere, the cells expanded due to trapped air and water. This would cause the adapter surface to break free. To stop this occurring again, small holes were drilled in the surface to allow for expansion.
The problems of the Apollo 6 test would have resulted in an abort of a manned Apollo flight. However, the booster rocket shakedown on this mission was invaluable, as none of the eleven subsequent Saturn V flights experienced any serious problems.
Documentaries often use footage of a Saturn V launch, and one of the most used pieces shows the interstage between the first and second stages falling away. This footage is usually mistakenly attributed to the Apollo 11 mission, when it was actually filmed on the flights of Apollo 4 and Apollo 6.
A compilation of original Nasa footage shows the jettisoning of the first stage (S-IC) and the interstage ring as seen from the bottom of the second stage (S-II), followed by the separation of the S-IVB third stage as seen from the top of the S-II. The hot, invisible hydrogen-oxygen flames of the J-2 engines on the S-II can be seen impinging on the S-IC and the ring. The S-II/S-IVB separation footage shows S-IVB ignition, and both films show the more conspicuous plumes of the solid lower stage retrorockets and upper stage ullage motors as they pull the stages apart.
The cameras filmed at high speeds causing an estimated 15 times slow-motion view of the sequence when seen in a documentary. The camera capsules were jettisoned soon after the first stage separation, and, though at about 200,000 feet in altitude, were still below orbital velocity. They then reentered the atmosphere and parachuted to the ocean, where they floated waiting for recovery. Only one of the two S-II cameras on Apollo 6 was recovered.
Another launch shot often attributed to Apollo 11 and other launches was shot on this day: it shows a view of the rocket lifting up, positioned relatively close up and dead center. The shot can be identified as Apollo 6 by examining the Apollo service module on the launch; Apollo 6 was the only Saturn V-launched Apollo craft with a white SM; all others were silver.
The Apollo 6 Command Module is on display at the Fernbank Science Centre, in suburban Atlanta,Georgia.
This was the final qualification flight of the Saturn V before its first manned flight (Apollo 8) (While Apollo 7 was the first manned Apollo mission, it used the smaller Saturn IB, not the Saturn V.) It was also the first mission to use High Bay 3 in the Vertical Assembly Building (VAB), Mobile Launcher 2 and Firing Room 2. Another objective was testing the Command Module re-entry system under extreme conditions simulating a worst-case return from the Moon. This objective was not met due to J-2 engine failures.
The S-IC first stage arrived by barge on March 13, 1967 and was erected in the VAB four days later, with the S-IVB third stage and Instrument Unit computer arriving the same day. The S-II second stage was two months behind them and so was substituted with a dumbbell shaped spacer so testing could proceed. This had the same height and mass as the S-II along with all the electrical connections. The S-II arrived May 24. It was stacked and mated into the rocket on July 7.
Testing was slow as they were still checking out the launch vehicle for Apollo 4, a limitation of the system where there wasn't two of everyone and everything. The VAB could handle up to four Saturn Vs but could only check out one at a time.
The Command and Service Module arrived September 29 and was stacked December 10. It was a hybrid, featuring the Command Module Number 20 and Service Module Number 14 after SM-020 was destroyed in a tank explosion and Command Module Number 14 was dismantled as part of the investigation into the Apollo 1 fire. After two months of testing and repairs the rocket was moved to the pad on February 6, 1968.
Unlike the near perfect flight of Apollo 4, Apollo 6 experienced problems right from the start. Two minutes into the flight, the rocket experienced severe pogo oscillations for about 30 seconds. George Mueller explained the cause to a congressional hearing:
Pogo arises fundamentally because you have thrust fluctuations in the engines. Those are normal characteristics of engines. All engines have what you might call noise in their output because the combustion is not quite uniform, so you have this fluctuation in thrust of the first stage as a normal characteristic of all engine burning.
Now, in turn, the engine is fed through a pipe that takes the fuel out of the tanks and feeds it into the engine. That pipe's length is something like an organ pipe so it has a certain resonance frequency of its own and it really turns out that it will oscillate just like an organ pipe does.
The structure of the vehicle is much like a tuning fork, so if you strike it right, it will oscillate up and down longitudinally. In a gross sense it is the interaction between the various frequencies that causes the vehicle to oscillate.
In part due to the pogo, the spacecraft adaptor that attached the CSM and mockup of the Lunar Module to the rocket started to have some structural problems. Airborne cameras recorded several pieces falling off it at T+133s.
After the first stage was jettisoned at the end of its task, the S-II second stage began to experience its own problems. Engine number two (of five) had performance problems from 206 to 319 seconds after liftoff and then at 412 seconds shut down altogether. Then two seconds later Engine Number Three shut down as well. The onboard computer was able to compensate and the stage burned for 58 seconds more than normal. Even so the S-IVB third stage also had to burn for 29 seconds longer than usual.
The S-IC first stage impacted the Atlantic Ocean east of Florida , while the S-II second stage impacted south of the Azores.
Due to the less than nominal launch, the CSM and S-IVB were now in a 178 by 367 km orbit instead of the planned 160 km circular orbit. But after two orbits of checking out the spacecraft and rocket stage the S-IVB failed to restart to simulate the Trans Lunar Injection burn that would send the astronauts to the moon.
It was decided to use the Service Module engine to raise the spacecraft into a high orbit in order to complete some of the mission objectives. It burned for 442 seconds, longer than it would ever have to on a real Apollo mission and raised the apogee of the orbit to 22,200 km. There was now however not enough fuel to speed up the atmospheric reentry and the spacecraft only entered the atmosphere at a speed of 10,000 m/s instead of the planned 11,270 m/s. This meant it landed 80 km from the planned touch down point.
Ten hours after launch it was lifted on board the USS Okinawa.
S-IVB reentered on April 25, 1968.
The cause of the pogo during the first stage of the flight was well known. However, it had been thought that the rocket had been 'detuned'. To further dampen pressure oscillations in the fuel and oxidzer pumps and feed lines, cavities in these systems were filled with helium gas from the propulsion system's pneumatic control system, which acted to attenuate the oscillations.
The failure of the two engines in the second stage was traced to the rupturing of a fuel line that fed the engine igniters. The igniter was essentially a miniature rocket motor mounted in the wall of the J-2 engine's pressure chamber. It was fed by small-diameter flexible lines carrying liquid hydrogen and liquid oxygen. During the S-II second stage burn, the hydrogen line feeding the engine number three igniter broke due to vibration. As a result, the igniter fed pure liquid oxygen into the pressure chamber. Normally the J-2 engine burns a hydrogen-rich mixture to keep temperature down. The liquid oxygen flow caused a much higher temperature locally and eventually the pressure chamber failed. The sudden drop in pressure was detected and caused a shutdown command to be issued. Unfortunately, the shutdown command signal for engine three was cross-wired to engine two. Engine two shut down and in turn its pressure sensor sent a shutdown signal back to engine three.
The problem in the igniter fuel lines was not detected during ground testing because a stainless steel mesh covering the fuel line became saturated with liquid air due to the extreme cold of the liquid hydrogen flowing through it. The liquid air damped a vibration mode that became evident when tests were conducted in a vacuum after the Apollo 6 flight. This was also a simple fix, involving replacing the flexible bellows section where the break occurred with a loop of stainless steel pipe. The S-IVB used the same J-2 engine design as the S-II and so it was decided that an igniter line problem had also stopped the third stage from reigniting in Earth orbit.
The spacecraft adapter problem was caused by its honeycomb structure. As the rocket accelerated through the atmosphere, the cells expanded due to trapped air and water. This would cause the adapter surface to break free. To stop this occurring again, small holes were drilled in the surface to allow for expansion.
The problems of the Apollo 6 test would have resulted in an abort of a manned Apollo flight. However, the booster rocket shakedown on this mission was invaluable, as none of the eleven subsequent Saturn V flights experienced any serious problems.
Documentaries often use footage of a Saturn V launch, and one of the most used pieces shows the interstage between the first and second stages falling away. This footage is usually mistakenly attributed to the Apollo 11 mission, when it was actually filmed on the flights of Apollo 4 and Apollo 6.
A compilation of original Nasa footage shows the jettisoning of the first stage (S-IC) and the interstage ring as seen from the bottom of the second stage (S-II), followed by the separation of the S-IVB third stage as seen from the top of the S-II. The hot, invisible hydrogen-oxygen flames of the J-2 engines on the S-II can be seen impinging on the S-IC and the ring. The S-II/S-IVB separation footage shows S-IVB ignition, and both films show the more conspicuous plumes of the solid lower stage retrorockets and upper stage ullage motors as they pull the stages apart.
The cameras filmed at high speeds causing an estimated 15 times slow-motion view of the sequence when seen in a documentary. The camera capsules were jettisoned soon after the first stage separation, and, though at about 200,000 feet in altitude, were still below orbital velocity. They then reentered the atmosphere and parachuted to the ocean, where they floated waiting for recovery. Only one of the two S-II cameras on Apollo 6 was recovered.
Another launch shot often attributed to Apollo 11 and other launches was shot on this day: it shows a view of the rocket lifting up, positioned relatively close up and dead center. The shot can be identified as Apollo 6 by examining the Apollo service module on the launch; Apollo 6 was the only Saturn V-launched Apollo craft with a white SM; all others were silver.
The Apollo 6 Command Module is on display at the Fernbank Science Centre, in suburban Atlanta,Georgia.
Apollo 4
Apollo 4 was the first flight of the saturn V launch vehicle, carrying no crew. It was also the first flight of the S-IC and S-II stages of the rocket.
This was the first flight of the Saturn V, the largest launch vehicle ever to fly successfully. It was also the first launch from Launch Complex 39 specifically built for the Saturn V. As well as being the first launch of the S-IC first stage and S-II second stage, it would also be the first time that the S-IVB third stage had been restarted in Earth orbit and the first time that the Apollo spacecraft had reentered the Earth's atmosphere at speeds approaching those of a lunar return trajectory. Because of all these firsts there were 4,098 measuring instruments on board the rocket and spacecraft.
This would be the first test of the all-up doctrine. It had been decided in 1963 that instead of testing each component of the rocket separately as had been done by Wernher von Braun in Germany during World War II, the rocket would be tested all at once. This cut down the total number of tests, as needed to accomplish President Kennedy's stated goal of a manned lunar landing by 1970, but it meant that everything had to work properly the first time (as the Soviets found to their dismay with their Moon rocket). Apollo program managers had misgivings about all-up testing but agreed to it with some reluctance since individual component tests would inevitably push the landing mission past the 1970 goal.
There were two main payloads on board. CSM-017 was a production model of the spacecraft. It was a Block I design meant for systems testing, and not the Block II spacecraft that had the docking mechanisms necessary for landing on the Moon. However it did feature some Block II upgrades such as an improved heat shield and a new hatch. The other payload was LTA-10R which was a model of the Lunar Module carried as ballast but with the same mass distribution as the real craft.
The first piece of the Apollo 4 to arrive at the Kennedy Space Center was the third stage. This was built by Dougas Aircraft Company and was small enough to be transported by plane, though it was no ordinary plane, being an Aero Spacelines,Inc.Pregnant Guppy. The other stages were much larger and had to travel by barge, with the first stage arriving next from Boeing Company at Michoud,Louisiana along the Banana River. The second stage was late in arriving but the rocket was still erected in the Vertical Assembly Building, using a huge barbell shaped spool in the place of the second stage.
The Command and Service Module (CSM) arrived at the Cape on Christmas Eve 1966, followed by the second stage on 12 January 1967. Only two weeks later the fatal fire in the Apollo 1 spacecraft occurred pushing all the schedules back. An inspection of wiring in the CSM found 1,407 problems.
The stacking of the S-II took place on 23 February. This was a precision process; supposedly the crane operators could conceivably "lower the crane hook on top of an egg without breaking the shell". The piece had to be unstacked after hairline cracks were found in another S-II. The CSM was finally ready as well and on 20 June it was mated to the rocket and the whole launch vehicle rolled out of the VAB on 26 August - six months after the originally scheduled launch date.
After a testing regime that lasted two months the rocket was finally ready for launch. The propellant started being loaded on 6 November. In total there were 89 trailer-truck loads of LOX (liquid oxygen), 28 trailer loads of LH2 (liquid hydrogen), and 27 rail cars of RP-1 (refined kerosene).
The five F-1 engines sent a huge amount of noise across Kennedy Space Center. To protect from a possible explosion, the launch pads at LC-39 were nearly four miles from the Vehicle Assembly Building. However, the noise was much stronger than expected and buffeted the Vehicle Assembly Building, firing room and press buildings. Ceiling tiles fell around Walter Cronkite in the CBS news booth. NASA later built a sound suppression system that pumps thousands of gallons of water onto the flame trench under the pad. A similar system is still used today with Space Shuttle launches.
The perfect launch placed the S-IVB and CSM into a 185 kilometer orbit. After two orbits, the S-IVB reignited for the first time, putting the spacecraft into an elliptical orbit with an apogee of more than 17,000 kilometers. The CSM separated from the S-IVB and fired its Service Propulsion System (SPS) engine to send it out to 18,000 kilometers. Passing apogee, the Service Propulsion System fired again to increase re-entry speed to 40,000 km/h, simulating a return from the moon.
The CM landed 16 km from the target landing site. Its descent was visible from the deck of the USS Bennington, the prime recovery vessel.
Documentaries often use footage of a Saturn V launch, and one of the most used pieces shows the interstage between the first and second stages falling away. This footage is usually mistakenly attributed to the Apollo 11 mission, when it was actually filmed on the flights of Apollo 4 and Apollo 6. Footage from Apollo 4 is even seen in the Star Trek episode "Assignment:Earth".
A compilation of original NASA footage shows the jettisoning of the first stage (S-IC) and the interstage, filmed from the bottom of the second stage (S-II), both from Apollo 4. This is followed by footage of the separation of an S-IVB second stage from the S-II second stage of Apollo 6. The glow seen on the jettisoned stages is due to the hot, invisible hydrogen-oxygen flames of the J-2 engines used by the S-II and S-IVB. The footage also shows the more conspicuous plumes of the solid ullage motors as they pull the stages apart before the main engines are fired.
The cameras ran at 15 times normal speed to show the events in slow motion. The camera capsules were jettisoned soon after the first stage separation and though at about 200,000 feet in altitude, were well below orbital velocity. They then reentered the atmosphere and parachuted to the ocean where they floated waiting for recovery. Both S-II cameras from Apollo 4 were recovered so that there is footage from both sides of the vehicle
This was the first flight of the Saturn V, the largest launch vehicle ever to fly successfully. It was also the first launch from Launch Complex 39 specifically built for the Saturn V. As well as being the first launch of the S-IC first stage and S-II second stage, it would also be the first time that the S-IVB third stage had been restarted in Earth orbit and the first time that the Apollo spacecraft had reentered the Earth's atmosphere at speeds approaching those of a lunar return trajectory. Because of all these firsts there were 4,098 measuring instruments on board the rocket and spacecraft.
This would be the first test of the all-up doctrine. It had been decided in 1963 that instead of testing each component of the rocket separately as had been done by Wernher von Braun in Germany during World War II, the rocket would be tested all at once. This cut down the total number of tests, as needed to accomplish President Kennedy's stated goal of a manned lunar landing by 1970, but it meant that everything had to work properly the first time (as the Soviets found to their dismay with their Moon rocket). Apollo program managers had misgivings about all-up testing but agreed to it with some reluctance since individual component tests would inevitably push the landing mission past the 1970 goal.
There were two main payloads on board. CSM-017 was a production model of the spacecraft. It was a Block I design meant for systems testing, and not the Block II spacecraft that had the docking mechanisms necessary for landing on the Moon. However it did feature some Block II upgrades such as an improved heat shield and a new hatch. The other payload was LTA-10R which was a model of the Lunar Module carried as ballast but with the same mass distribution as the real craft.
The first piece of the Apollo 4 to arrive at the Kennedy Space Center was the third stage. This was built by Dougas Aircraft Company and was small enough to be transported by plane, though it was no ordinary plane, being an Aero Spacelines,Inc.Pregnant Guppy. The other stages were much larger and had to travel by barge, with the first stage arriving next from Boeing Company at Michoud,Louisiana along the Banana River. The second stage was late in arriving but the rocket was still erected in the Vertical Assembly Building, using a huge barbell shaped spool in the place of the second stage.
The Command and Service Module (CSM) arrived at the Cape on Christmas Eve 1966, followed by the second stage on 12 January 1967. Only two weeks later the fatal fire in the Apollo 1 spacecraft occurred pushing all the schedules back. An inspection of wiring in the CSM found 1,407 problems.
The stacking of the S-II took place on 23 February. This was a precision process; supposedly the crane operators could conceivably "lower the crane hook on top of an egg without breaking the shell". The piece had to be unstacked after hairline cracks were found in another S-II. The CSM was finally ready as well and on 20 June it was mated to the rocket and the whole launch vehicle rolled out of the VAB on 26 August - six months after the originally scheduled launch date.
After a testing regime that lasted two months the rocket was finally ready for launch. The propellant started being loaded on 6 November. In total there were 89 trailer-truck loads of LOX (liquid oxygen), 28 trailer loads of LH2 (liquid hydrogen), and 27 rail cars of RP-1 (refined kerosene).
The five F-1 engines sent a huge amount of noise across Kennedy Space Center. To protect from a possible explosion, the launch pads at LC-39 were nearly four miles from the Vehicle Assembly Building. However, the noise was much stronger than expected and buffeted the Vehicle Assembly Building, firing room and press buildings. Ceiling tiles fell around Walter Cronkite in the CBS news booth. NASA later built a sound suppression system that pumps thousands of gallons of water onto the flame trench under the pad. A similar system is still used today with Space Shuttle launches.
The perfect launch placed the S-IVB and CSM into a 185 kilometer orbit. After two orbits, the S-IVB reignited for the first time, putting the spacecraft into an elliptical orbit with an apogee of more than 17,000 kilometers. The CSM separated from the S-IVB and fired its Service Propulsion System (SPS) engine to send it out to 18,000 kilometers. Passing apogee, the Service Propulsion System fired again to increase re-entry speed to 40,000 km/h, simulating a return from the moon.
The CM landed 16 km from the target landing site. Its descent was visible from the deck of the USS Bennington, the prime recovery vessel.
Documentaries often use footage of a Saturn V launch, and one of the most used pieces shows the interstage between the first and second stages falling away. This footage is usually mistakenly attributed to the Apollo 11 mission, when it was actually filmed on the flights of Apollo 4 and Apollo 6. Footage from Apollo 4 is even seen in the Star Trek episode "Assignment:Earth".
A compilation of original NASA footage shows the jettisoning of the first stage (S-IC) and the interstage, filmed from the bottom of the second stage (S-II), both from Apollo 4. This is followed by footage of the separation of an S-IVB second stage from the S-II second stage of Apollo 6. The glow seen on the jettisoned stages is due to the hot, invisible hydrogen-oxygen flames of the J-2 engines used by the S-II and S-IVB. The footage also shows the more conspicuous plumes of the solid ullage motors as they pull the stages apart before the main engines are fired.
The cameras ran at 15 times normal speed to show the events in slow motion. The camera capsules were jettisoned soon after the first stage separation and though at about 200,000 feet in altitude, were well below orbital velocity. They then reentered the atmosphere and parachuted to the ocean where they floated waiting for recovery. Both S-II cameras from Apollo 4 were recovered so that there is footage from both sides of the vehicle
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