Apollo 6: A Major Unplanned Accomplishment.

this episode of the history guy brought to you by mova globes place them in the light sit back and watch them spin and be impressed stay tuned for a message at the end of the episode [Music] on july 20th 1969 at 10 56 pm eastern time television images were broadcast worldwide as neil armstrong put his foot on the lunar surface that one small step for man was a similar moment in world and american history it is seared in the national consciousness it represented the greatest dreams of mankind made real via yankee ingenuity and yet that memorable moment wasn't the first apollo mission it wasn't apollo 1. in fact it was apollo 11 and it really seems like americans aren't terribly familiar with all those other apollo missions that came before apollo 11 or for that matter for those missions apollo 12 through 20. in fact it seems that one of the most memorable moments in american history is part of a program that is darned near forgotten history there was much more to the program that led to man's first extraterrestrial steps than that first step and among those missions one is perhaps more forgotten even than the others because of coincidence of history apollo 6 the apollo mission that almost failed deserves to be remembered the apollo program was actually quite complex there were 10 unmanned missions between 1961 and 1965 testing various apollo program components using the saturn one launch vehicle five used jupiter nose cones and mostly tested rocket components they were designated sa for saturn apollo one through five five more tests using saturn one rockets used boilerplate or simulated apollo spacecraft to verify their launch aerodynamics those were designated as101 through 105. three more launches in 1966 tested components of the command and service module using upgraded saturn 1b rockets they were designated as-201-203 there were still more tests of apollo escape systems the so-called little joe 2 rocket as well while news was following breathlessly at the time i think it's fair to say most americans today are generally unfamiliar with the host of launches that came before the officially designated apollo but even then there is confusion what would have been as204 had been the first of the missions to be manned by a crew and so nasa employees instead colloquially called it apollo 1. and disaster struck apollo 1 on january 27 1967. during a launch simulation designed to test power in the command module a short an electrical arc started a fire in the high oxygen environment it spread quickly pressure inside the module made it difficult to remove the hatch from the inside while flames and gases escaping through access panels slowed rescue attempts from the outside astronauts gus grissom edward white ii and roger b caffey perished in the flames in october 2013 edition of popular science notes the widows of the apollo 1 crew asked that nasa retired the mission designation in honor of their husbands so that they might keep the flight that they never got to fly nasa of course agreed apollos 2 and 3 were intended to be additional man tests but investigations due to the fire were resulting in significant redesign and didn't make sense to schedule tests of a version of the spacecraft that wouldn't be going to the moon apollos 2 and 3 were cancelled this left confusion in the designation system popular mechanics writes the agency could proceed in sequence and name the first mission after the fire apollo 2 or could count the unmanned saturn 1b test fights as part of the apollo series and retroactively rename them to have apollo designations as201 would become apollo 1 a as202 would become apollo 2 and as203 would become apollo 3. this meant subsequent flights following the fire would begin with apollo 4. on april 24 1967 nasa's office of manned space flight announced that as204 would be officially recorded as apollo 1. as201 as202 and as203 wouldn't be renumbered in the apollo series but subsequent missions would be named beginning with apollo 4. thus there were no apollo 2 or 3 and it would be some time before nasa would risk another manned mission apollo 4 was the first all-up test of the larger saturn v rocket taller than the statue of liberty and 13 times heavier that would be used to take a mission to the moon and the first apollo mission to be launched from the kennedy space center apollo 4 was to be an unmanned test to qualify the launch vehicle spacecraft and the ground systems for the planned lunar landings to come after several delays launch occurred on november 9 1967 as the first test of the massive saturn v rocket was a major press event with dignitaries watching the launch from bleachers the massive rockets shook buildings throughout the space complex much more than expected the entire mission lasted just under nine hours from liftoff to splashdown there were minor issues but everything occurred within tolerance president johnson said this launching symbolizes the power this nation is harnessing for the peaceful exploration of space apollo 5 was intended to test components of the lunar module the unmanned mission did not require the expensive saturn v and used the saturn 1b rocket that would have carried apollo 1. it launched january 22 1968. again there were minor issues but the mission was deemed a success nasa's hopes were that apollo 6 would be a notable last its objective was to fully qualify the saturn v launch vehicles being able to carry an entire apollo spacecraft all the way to the moon unlike apollo 4 it would be fired for translunar injection that is it would prove that it could go all the way simply put it was a dress rehearsal a last test before nasa would again risk its astronauts and if the mission succeeded it would be the last unmanned mission of the apollo program nasa engineer jay green who was the flight dynamics officer explained in an interview in 2004 it was about a 12-hour flight intended to insert into earth orbit much the way that we went on a lunar mission and then it was going to do a full-up translunar injection first time that had ever been done but he noted this was very similar to apollo 4 and everyone expected it to be a nominal mission this time however the mission was just not that interesting to the public the first launch of a saturn v might have been a spectacle but a second launch still with no astronauts on board just didn't garner much attention again facing delays the launch was finally moved to april 4th received not a mention in the new york times that day its front page was dominated by news of the war in vietnam the ted offensive had occurred just a few months before it was a hectic time for news on march 31 president johnson made the surprise announcement that he would not seek re-election it did get mentioned in the palm beach post on page a13 the post reported nasa's goal for the mission to be a success the rocket's three stages had to fire with precision to move the top stage and its payload into orbit this third stage had to successfully orbit twice around the earth its engine would have to then reignite and carry the rocket high enough to reach the moon the module's rocket engine would then be used to act as a break it would then have to separate from its support module and position its heat shield for splashdown the launch occurred at 7am from launch complex 39a at kennedy space center the official mission report says that the liftoff was normal but during the s-1c boost phase oscillations and abrupt measurement changes were observed the nasa webpage explains two minutes into the flight the first stage experienced about 30 seconds of vertical oscillation known as pogo effect which caused no serious damage but would have been very uncomfortable for any crew nasa administrator george mueller later explained to the congressional hearing pogo arises fundamentally because you have thrust fluctuations in the engines those are normal characteristics of engines all engines has 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 resonant 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 cause the vehicle to oscillate and so the rocket that was supposed to prove that it was ready to carry men to the moon had become a giant tuning fork a nasa's special publication called moonport a history of apollo launch facilities and operations noted that this would be a problem for a live crew as it produced unacceptable g-loads in the spacecraft and that was just the start things were starting to fall off the spacecraft moonport continues simultaneously the spacecraft lunar module adapter was experiencing trouble made of bonded aluminum honeycomb the adapter not only housed the lunar module but connected the command service module to the saturn launch vehicle at t plus 133 seconds sizable pieces of the outer surface more than three square meters flaked off and the report goes on more was to come green describes what came next we got to the second stage and we had a visiting booster engineer who was watching the flight and then over the airwaves i heard him say that looks like two engines out this could be a significant problem green explains it turns out per the flight rules two engines out was supposed to be a loss of control case but the rocket was able to compensate burning the remaining three engines slightly longer green said by the time the booster guys realized that we lost two engines it turned out the vehicle was stable and so we just let it fly the question now is whether the rocket would achieve orbit green explained the vehicle lofted and then got on third stage and it started to drive straight at the earth and based on that i had a limit line that we were approaching and had my sweaty little fingers on the abort switch and the thing finally straightened out and it made it into orbit probably the first time we ever inserted into orbit going backwards based on the way the guidance missed its target box and just kept on trying and till it got there but the troubles didn't end there after two trips around the earth the rocket on the third stage the s4b was supposed to reignite this was to prove the spacecraft carrying approximately 80 percent of the load of a manned mission could propel the craft to a trans-lunar injection a trajectory to reach the moon although for this mission the rocket was to break before getting there when the time came however the mission report says simply an attempt to reignite the s4b engine for the transluder injection firing was unsuccessful green said everything looked copacetic and we came up on translunar injection and counted down and s4b engine was supposed to light and it never lit with translunar injection out the window mission engineers decided to simply bring the mission home switching to essentially the mission profile of the previous apollo 4 mission green explained so i got to throw my little switch that separated the spacecraft from the booster and we went on and completed a semi-nominal mission the capsule splashed down approximately 10 hours after liftoff 43 nautical miles from its planned touchdown point and was picked up by the amphibious assault ship uss okinawa nasa director samuel phillips said in a post-mission statement there is no question that it's a less-than-perfect mission this of course raised concerns as the mission was supposed to be the final proof that apollo was ready to send men to the moon mueller was quoted in the new york times we are all disappointed this will have to be defined as a failure you might think that the failure of apollo 6 would be big news given the importance of the apollo program and the attention that had been paid to apollo 4 the previous november but if lbj's announcement and the vietnam war had conspired to keep apollo 6 off of the front pages on april 4th on april 5th few americans were thinking about the space program the headline of the new york times that day read martin luther king slain in memphis in turbulent times the last unmanned mission of the apollo program was virtually missed by an american public that was distracted and suddenly in mourning it became almost instantly nearly forgotten history you might imagine that the multiple issues would have given nasa pause on again risking a manned mission but the result was almost the opposite phillips instead described the problems with the mission as a major unplanned accomplishment instead of proof that the system was unready the mission had demonstrated that the second stage could successfully function even with two of its five rockets cutting off early and that even with multiple errors nasa could bring the capsule safely home nasa was convinced that they could solve the problems of the pogoing in the engines that cut off early or didn't start and decided that another unmanned mission was unnecessary green said so we had three engines out and this aborted profile we ran an approximation of a nominal entry and everything went so well that we man-rated the saturn v based on that and the next time we used a rocket we went to the moon apollo 7 is well another mission that's largely forgotten but that is a story for another time if you're a fan of the history guy then i'm sure you've seen these amazing globes on my set like this highly detailed topographically accurate globe of the moon based on topographical photos taken by nasa and that's right it spins all by itself no batteries no wires powered just by ambient light and the earth's magnetic field these are called mova globes and their first of its kind technology allows them to rotate merely by exposure to ambient light and they come in over 40 designs you know these things are just cool not only do they spin by themselves but they have amazing detail if you put one on your desk i guarantee you it will be a subject of conversation and the best part is that history guy viewers get a special discount ten percent off six inch and eight and a half inch globes all you need to do is use the code the history guy on mobaglobes.com i hope you enjoyed this episode of the history guide check out our community on the historyguyguild.locals our webpage at thehistoryguy.com and our merchandise at teespring.com or book a special message from the history guy on cameo and if you'd like more episodes of forgotten history all you have to do is subscribe [Music] [Applause] [Music]

Channel: The History Guy: History Deserves to Be Remembered

Views: 149,834

Keywords: history, history guy, the history guy, apollo, nasa

Id: itV97aOL4Hs

Length: 15min 26sec (926 seconds)

Published: Fri Apr 22 2022