Planning The Apollo Missions, Part 2

that was an exhilarating time in one that I'll always remember U The Briefing Joe asked me to give today is was not the one that I gave that day it was it was U the one that a gentleman by the name of Mars jenin gave who was one of my bosses at the time uh on on as Joe said the software considerations and constraints excuse me uh relative to the mission um the one I gave that day was on uh the return to Earth a board analysis and planning and uh if time permits I might uh try to sneak a chart or two at the end of this from my briefing um to U make this as as faithful a recreation as possible I'll try to or I'll at least attempt to use present and future tenses instead of slipping into the past tense thing which is difficult to do and U um um also as as you you may have already noticed because Mars was a uh an Englishman that uh uh again to further U recreate accurately that uh that briefing is why I'm using a a British accent today in in instead of my my natural Texas draw and I'm going to continue to do that just if I if I slip back into into my natural one just yell U um could I have the first chart please in terms of the uh overall U uh Mission software uh considerations and and U and strategies uh as as this chart shows obviously they were driven by combination of crew safety and and Mission success but the other other point was that it would it the strategy was to really have a partnership between the onboard and the ground it was not just going to be the the uh onboard show for very various reasons uh as as the uh uh first bullet indicates of course the onboard uh software capability did have um plenty of uh of features that uh ensured crew safety uh as well as enhanced Mission success and uh helping that uh uh capability was the ability that it had to accept uh information from the ground uplink from the ground during the mission the the ground uh capability was actually uh Prime and essential in in certain cases uh one of the previous speakers mentioned that U uh the U much of the navigation during the mission was Prime from the ground as as well as a lot of the uh targeting maneuver targeting uh uh and and likewise the ground provided enhancement to Mission success as well as served as a provider of various peripheral data like a and Los times lighting predicted lighting conditions and so on and then there uh another part of the strategy was when appropriate to uh to use combined U onboard and ground software Solutions uh when when so combining would enhance crew safety or or provide a more optimal from uh uh resulting Mission plan or trajectory uh have the next chart please elaborating a little bit on the on board's capability uh relative to crew safety it it the the the plan is to I'll try to use present tense the plan is to uh is to for the on board to have an independent capability to return uh in case to cover the obvious case of loss of communications from the ground when the ground cannot provide return to Earth uh targeting maneuver targeting and and nav navigation uh uh support then the own board will have an independent capability to provide that now in in uh in uh in actuality what what happened it even that turned out to be somewhat of a combination of on board and ground because uh uh we ended up using what uh what's called Advanced block updates where the ground would would send it return to Earth Solutions uh for some future time so that you lost Cal between then and and that future time you would have a block update maneuver to execute U it it as I mentioned it it the on board will have the capability to accept ground updates it will provide compatibility of software between the uh uh primary guidance system and the and the and the lamb and the abort guidance system uh example being the compatibility of of targeting for Lim asent it will provide a double check on relative state for rendevu where the limb is uh determining the relative state with its radar the CSM is determining relative state with seant tracking of the limb um and uh also the capability will exist for the limb to direct a CSM active rendevu uh the the solution would be computed on board the limb and voiced over to the CSM where the CSM pilot would punch it in the discy the maneuver targeting information U and also the software will provide meaningful crew checks in uh in terms of the input and output data and display something that in a in a format that has some physical meaning to the crew wherever possible in terms of mission success of course the uh the onboard uh software will be providing the necessary steering or thrusting uh uh guidance programs uhu for translunar injection though the Saturn will be uh primed for translunar injection be providing the the uh steering uh using its iterative guidance for that uh maneuver the uh CSM uh CMC computer will have uh backup capability to uh steer translunar injection if for some reason the there's a loss of capability for the Saturn to guide through translunar injection and as I mentioned there uh uh the onboard will have the ability to accept alternate targeting from the ground to provide more Optimum Solutions next chart please the basic on board GNN software capability is uh described on these charts there are four classes of uh of programs uh proposed for on board U the navigation class where you have observations uh nav observations fed into a trajectory determination processor uh outputting which it would then output uh after it does its thing the current smooth position and velocity determination answering the question where are we and to answer the question where will we be we have the class called dead reckoning that was one of Mars's favorite terms I call it trajectory prediction he calls it dead reckoning but it it involves uh taking an ephemeris or state Vector input into a trajectory prediction uh uh processor and uh and outputting the best estimate of future position and velocity and deter and you also had the pre thrust programs which would ESS Al determine the uh change of course required coming out with the target objectives for the thrust programs uh that's where the targeting was set up and configured to tell the steering uh uh thrust programs what to steer to then you you did have finally have the for the purpose of maneuver control youd had the thrust programs themselves which uh in uh included the steering equations to achieve the uh desired Target conditions and including the achievement of of the desired C off conditions uh elaborating on that just a second the uh trajectory determination processor uh uh the basic component there was a cal is proposed to be a calman filter which which will filter out noise in the uh be a mathematical formulation to filter out noise in the measurement data as well as provide the capability to solve for uncertainties in the various Dynamic models primarily the gravity model uh trajectory uh predict ition processor uh will feature the inky method of numerical integration for you numerical integration Buffs you all know what the inky method is that's where you do the numerical integration instead of in the equations of motion in totality you just numerically integrate the Deltas from a base two close form two Body Solution uh so that you and and our studies up to this time show that's will provide a superior accuracy or Superior speed same accuracy if you want to take larger steps the pre thrust programs as I mentioned set up the uh the the targeting they provide determine the uh initial thrust command attitude and determine the preferred platform alignment the thrust programs uh include the mit's um cross product steering which is a simple but reliable uh steering law which essentially requires the the U cycle to cycle determination of a of a close form velocity to be gained which is kept that velocity gained Vector is kept inertially fixed and the steering law shrinks its values as you go through the burn the E guidance is a more sophisticated guidance law for when you're trying to control more parameters such as be required for the limb ascent and descent then you got the local vertical coordinate or external Delta V steering law where you're actually thrusting along local horizontal or out of plane coordinates uh next chart please uh because of the capacity limitations uh in the onboard computer and the schedule limitations how much schedule time we've got to uh to uh implement the requirements in the onboard computer there will be uh uh significant omissions that we will not be able to get into the onboard computer the the self-checking will be restricted the logic to avoid gimbal lock will not be included uh there will be no concentric sequence logic automated in the CMC as I mentioned earlier for the Cs CSM active Rendevous they have to get that uh that maneuver targeting and planting from the limb uh or the ground the um there'll be an ABS no Flight Plan prediction or optimization capability no point return back to Earth it will have return to Earth capability but no ability to return to a specific point on the Earth and U as I said there will be no uh sophisticated iterative steerings uh like the Marshall uh guidance for transl injection instead the the more simple cross product steering will be used next slide please as regards the ground supplementary backup functions uh um many uh if not most of the the target determinations will be uh uh done on the ground and and Uplink they will also provide pilot monitoring information for manual Maneuvers uh and they will provide especially for contingency situations much more extensive flight planning optimization realtime Mission planning uh function and it also provide an umpiring function between the pings and AGS especially as regards uh range rate information to assist the limb in asent switch over monitoring and that navigation and the everpresent dead reckoning down here uh next chart please uh at this point in Mars's presentation he went into about an hour and a half discussion of the various targeting techniques to be used and I've just selected three or four of them to give you a sampling Mars was a targeting junkie and he he he loved it and he taught me to love it also uh type one targeting uh uh was for a trans lunar injection and this was to uh Target the uh uh trans lunar steering for the U if the CSM was going to be doing it instead of the um uh Saturn so it had to be a very simple close form uh way of computing a velocity be gained so what you did you from the pre flan pre-flight plan that uh that Pete was talking about you'd pick off uh near the uh uh Saturn cut off Vector you pick off a state Vector uh uh def determine a conic ellipse pick off a position Vector from that U that with the energy of the of the ellipse and and by the way Pete's depiction of the ellipse was much more accurate than Mars's Mars showed it a little short on the semi- major axis it really went way out like that like Pete showed uh but you with the position vector and the of this ellipse that together with the a a position Vector in real time somewhere in the vicinity of the translunar injection is all you need to Define that conic and therefore Define a velocity gained in a in a cyclical um uh sense to supply the U velocity be gained to the cross product steering uh the tarting type one also was used for lunar orbit insertion uh um with the only uh additional wrinkle that the U the target position was constrained to be the same uh length as the current position so that you were forcing it to burn into a circular orbit next chart please the type two targeting uh was used for the translunar midc courses uh again you they were conic based this is a little too complicated because I'm about to run out of time uh but you essentially take a u a u the the pre again the pre-flight computed trans lunar trajectory note where it uh punctures or pierces the lunar sphere of influence at time two or point two uh now you're on a dis in real time you're on a disperse trajectory at at time or Point T1 you uh Precision integrate where you're going to end up at the same time as T2 call that T3 you compute a conic trajectory between T1 and and T3 at the uh at the same Delta time as between T1 and and T2 you then compute another conic trajectory between T1 and T2 to compute the VG apply it to Precision trajectory and Walla you hit that point if all goes well also I'd like to put uh one uh one longstanding myth to rest once and for all uh that that when we did fly the actual missions uh and and punctured the sphere of influence there was not an audible pop it was a low hiss and so the targeting type two is also used with a little different wrinkle for the uh second third midcourse Corrections inside the lunar sphere of influence approaching the moon I'm not going to have time to go into the details of that next chart please and targeting type 3 is even uh more interesting but uh and because I won't even have time to begin here but but essentially again it's conic based but here you have uh the conic centered both at the Earth to consider as well as the conic at the Moon hyperbola here ellipse here you iterate the two and until you match them up at the sphere of influence in terms of the energy and position and then once you get a match on the conics then you go through the same procedure with Precision uh backtracking the Precision back to the lunar sphere of influence forward until you match at the uh sphere of influence and the last chart a backup one number one I'm going to sneak in one from my pitch no uh go to the next one backup number one there we go uh this is one of the most fun things I ever did uh it involved doing lunar doing return to Earth board analysis from the family trajectories result ing from a premature Loi shutdown in Words If you're burning into lunar orbit and you had to be able to uh recover from a premature shutdown at any time in the burn you ended up having to analyze a this is a trajectory analyst Dream by the way you ended up having to analyze a whole family of trajectories ranging from Escape hyperbolas to ellipses to Circular orbits to even these weird unstable ones which start out retrograde relative to the Moon come down and and change me come come back POS a grade couple with the fact you were trying to you had nearly an infinite number of uh maneuver possibilities to play with to figure out how to best recover from both time critical and non-time critical situations uh that was fun and that concludes my talk any questions we have one question hereis yes was there similar analysis to the one Ron just showed for the trans lunar injection burn yes there was you get the a similar family there and also for the transar injection burn you get a similar family the the one for tli had interesting properties somewhat different from the the lunar ones but they were interesting also thank you very much our next speaker will be Doug broom who was in the Apollo spacecraft program office in 1966 and who is now at NASA headquarters in the office of Space Science and applications and he will discuss the communication systems which we used Doug key word was that I was I'm in NASA headquarters that's why the 10 key charts I needed today are missing um things haven't changed much since I worked here uh Owen the first time Owen gave that Owen made it the elderly gentleman here on my right the first time that he gave the uh presentation on constraints was interesting he had an overlay of the Moon and he would flip an overlay for each set of constraints he'd flip an overlay that blacked in part of the Moon and he got down to his last constraint he flipped it over and the scream was entirely black and he says gentlemen we cannot go to the Moon okay so he's too old to remember that sort of thing but um Owen and I are related he's my grandfather since I'm from headquarters I'll take the opportunity to give you a commercial I'm also the program manager for the Hubble Space Telescope and if God will quiet the Sun and air and coin will give us a an STS in March we're going to put it in orbit and it'll be the greatest thing we've done since we landed on the mountain how's that okay I'm going to have to play with the charts a little bit since they're not the ones I was looking for but um Communications with a spacecraft is a lot like your relationship with your mother your mother never wants to let go of control whereas you always know that you can handle any problem that comes into your life and you don't need control from your mother so flight crews are pretty independent they think they can handle any emergency but the ground never wants to let them out of sight out of mind out of control so that leads to a problem with Communications okay and the the the thing that we had we had multiple problems going one was that particular problem that particular problem was manifested because in the fact that a large suite of things that already existed and we were stuck with trying to live with what we had and at the same time minimize power and weight requirements on the spacecraft so we'd finished the Mercury program started the geminy program and everything in those programs was done at V HF VHF or UHF none of which would work at the moon the uh deep space Network at JPL was operating at about 980 as I recall megahertz and was moving over to espan and uh they had the only systems that would operate at the kind of distances we we needed so our problem was we needed to operate from here to the pad which turned out to be fairly difficult and then from the pad to Earth orbit then Earth orbit to trans lunar and then from from uh the Earth to uh trans to the lunar surface then on the lunar surface you got two guys out you've got a guy orbiting the spacecraft you got people on the ground you've got a television set or camera you've got all these different ways and the links all have to somehow work together to get back down to a TV screen here at Mission Control and in in the general public so what we wound up with was one of everything uh we had an HF system a VHF systems we had uh UHF systems and we had San systems and ultimately if we'd kept flying I think we would have gotten around tojust the sban system which was the ultimate goal the goal was to go from the transition period of all the different frequencies to the sban system which be a single unified system at the same time there were other transitions going on we had uh we had the transition if I can find where I wrote that we had to transition from digit from analog to digital systems you know everything at one time uh if anybody else is a old in the room everything at one time was done at Analog you had two cycle per second bandwidth telemeter channels things like that uh the um everything all the circuit designs were done in analog one way of dealing with analog was you overdesign everything and you put buffers in and as the system degrades you still get an adequate signal out the other way was designed it where it work right in the first place and then it would just degrade and uh that was a lot of the block one Commander service module system uh so let's see there was a third there was a a third integration going on and I don't recall what it was okay the television in case you've heard that there was a very systematic approach to putting television on the on the spacecraft you're wrong uh there had been an experiment I guess it was gmany we did the line scan thing that looked terrible the Russians had put up television so we tried and it looked terrible and uh some of the somebody was talking about the Giants of the space industry had decided never to be that embarrassed again and um so we worked to plan George Miller did not want television on Apollo so he would he would say no and we'd say yes but he never told us to quit so we kept building communication system to handle color television and each every other month or so I'd go with this group up to Washington and I got to give the presentation on color television because I was youngest and if I got fired I was the most Expendable and um so we finally decided that this time we were going to take the big guns wovon Brown himself was going to say that television was required for Apollo to maximize the political everything of the program but Warner dozed off while I was giving my pitch and um I do that now and but fortunately Sam Phillips was sitting behind him and Sam you the criticality of this decision because we had already installed the camera and JSC operated no differently then than it does now okay so um so I started working my way towards where W was sitting swinging the pointer against my leg and Sam caught what I was about to do so he leaned forward and when I popped the table in front of w and woke him up Sam said television television and W says oh yes if I think we must go to the Moon with color television it is what the people of America have paid for and then he dos back off so that is how in his British accent we got television on Apollo okay uh let me have the first two view graphs please now you see why they sent me to headquarters uh these are the these are the the kind of things we were trying to do and I've been over them a bit uh voice Telemetry we had two rates ranging tracking up data voice and data playback television data and television had to be from a Command Module had to be from the lunar surface so that brought us multiple sets of problems and then there was a science Bay in the uh service module that we put in at one point and there was a science package left on the moon so that was two more links then you had uh VHF voice the reason for this is you know you had airplanes around the world that were equipped for VHF recovery for military purposes and for HF so we had to carry those because we weren't sure we didn't know much about what we're going to do with Apollo regardless of what these folks say and weren quite sure where it was going to come down sometimes so we had to make sure that somebody somewhere could find it and uh that was the reason for the HF for example HF you know if it bounces long enough somebody will hear it and the ultimate goal of course is to home in on that and find out where the spacecraft was and that's why they all went down to the astronauts all went down to Canal Zone and learned to eat rattlesnake and Bo constrictor and things like that that was their level of confidence in what we were going to do for them okay so the uh the problem of course you know the Mercury Network which was in the geminy network where all these stations around the world and as I said they had the VHF and UHF systems next VI graphs please now this is where you're going to have to use your imagination because there were five view graphs in this set okay pretend that's the Earth uh the see the real the problem here is this is the most complex you've got two astronauts they have to be able to talk to each other and they want to talk in duplex so if something goes on you don't have one yam jaw similar to Owen's presentation you know that you just can't shut them up and get a word in and um then you ought to be able to communicate through the lunar module then translate over to espan and go to the Earth same time you've got the command service module at the time there was no espan syst no sban frequency domain set aside for uh deep space Communications and that activity had to go on in parallel and there was an international body that that we never were quite sure was going to say we could do this while we were building all the equipment and towards the end they finally approved it and we were able to use use it um when Envision the fact when you're near Earth and now this is a command and service module you're near Earth you've got these communication links with the Earth there's a a lot of the problem with communication became one of management everything had to be multiply switched and then it was a big long procedural thing you had to go through to make sure that nobody threw the wrong switch at the wrong time because you had a very complex system of relays with backups and the problem with any system that's very flexible is then you have to come along and constrain it later to make it work the way it's the way to make it work at all let along the way it was supposed to so uh I don't recall except for the communications between the block house and the pad I don't recall ever having a communication problem there was a serious problem there for other reasons now when we were're looking at I think it was Apollo 15 Rover first time around I think it was Apollo 50 and it became obvious the Rover was going to go a little too far out so communication packages were added to the um to the Rover itself that you could relay Eva through and um Joe I see Joe Mackenzie back there he participated in that development it's a lunar communication relay unit then it dawned on somebody you also needed television for that so you put the camera on the front end of the Rover and then it relayed through the l l crew or whatever they called it and um that gave the link then directly from the Rover to Earth so you had a communication link from The Command Module circling the moon to the earth communication link from the lunar module sitting on the moon to the earth and a communication link from the Rover to the Moon sitting on the earth Lo Rover to the Earth sitting on the moon so it was very it was a a complex system and um all almost uh well I think I'll stop at that what's the next next chart please um the as I said the frequencies we're talking about here the span system for lunar module and Command Module they was where the as I recall it was a 228 to 230 ratio between transmit and receiver the other way around the um this number in the interest of accuracy my light doesn't work yet that number is 21106 40625 see some of us never forget anything uh that's the way you do the space station budget is of that many decimals uh they down link is a uh was 22875 and that was a coherent link with the up link and you'll notice over here if you do the calculations if you care about it they're the same ratio and we also had an additional down link from The Command Module for stored data uh the antenna system was a rather complex system and there were multiple power levels that were available also the antenna the High Gain antenna had multiple switching so that the crew wouldn't have to bother with trying to point it it could lock up on the earth this U as it moved out it would get get to compensate for the loss of signal due to longer distance it also would switch down and increase the decrease the uh beam width and therefore increase the gain of the antenna so it's a rather neat transition from the Earth to the Moon uh next please for the CSM systems which our ultimate goal was to drop the VHF system but uh and I suspect that was done with the U shuttle I went off to become a private detective and never check back the uh see 5 wats was the power on those and they Omni antennas on both spacecraft we had but again because of the uh fact that you had to break the Command Module from the service module during re-entry we had to have multiple sets of antennas there also next few guys please the then for Recovery uh we had high frequency system at 10.6 Mega Cycles we took that off in Block two and it was a fortunate move because it left a coal plate in the block two spacecraft that was unoccupied and it occurred to somebody at one point that U the lunar module had a rendevu radar it could use the find the command and service module but there was a problem that if you got to a safe low altitude with the lunar module there was no way for the Command Module to come down and find the lunar module so the uh question was how could we modify the system we had since we were uh going to launch Apollo 8 fairly soon we had we were given 13 and a 12 months to develop some system we took that coal plate put a digital range rate range and range rate system on it and used some spare wires in the GNC harness to uh give a range and range rate capability to the voice system within the Command Module so the use range and range rate and the optical s in the Command Module to find the lunar module so for 15 million here you got the equivalent of what $100 million Rond radar in the lunar module a little commercial there too we used to have two divisions a Command Module division a lunar module division lunar module division wasn't as smart as a Command Module division okay um then from the Moon I get to say that since they're not here then from the Moon U we had this separate package at 2119 and uh those transmitted for quite a long time when they got over to the um to the uh nuclear powered systems and I was told I had one minute so I'll quit I'll be the only guy up here who did this on time any questions besides the fact I don't have to get fired that it I saw somebody uh um is that legal the question is could you tell us a little more about the scientist Hubble after whom the Hubble Space Telescope is named we're getting a second commercial okay Edwin Hubble was a guy who finished high school and be was going to be a professional football player and instead World War I came along and he volunteered and got shot to pieces and decided he couldn't be a football player so he went back to college and became an a lawyer he got bored with law and he went back to college and became an astronomer uh after he went into the astronomical business he noticed that uh that there was some motion that that other people weren't reporting in the um with with what they were seeing in photographic plates and he came up with the idea that there was a rate at which stars were moving away from us and that rate was a function of the distance away and that gives rise to the term the Hubble constant The Hub constant was he misestimated a little bit for the techniques he had he was very accurate and that as an argument over whether he's 100% offer he right on but what that tells us is that the universe is indefinitely expanding the issue then becomes is it is expanding to a point at which it will it will go to equilibrium and stay is it expanding to a point where it'll continue to expand forever or is it expanding to a point which it'll stop and then collapse on itself that's vitally important to us since it may happen in two billion years and that'll be called you've heard of The Big Bang that'll be called a big crunch and that that is the the name for it the jargon name for it but the uh the key is that um Hubble Hub was was a guy who really discovered the fact that the Universe was not a static thing that it was not just sitting here and that we were not one element and and the universe was that little thing we can go lay on our back in the grass and see uh that in fact it just goes on and on and on and the purpose of the hble Space Telescope is number one to better evaluate the U Hubble constant to give us a better feel for the age of the universe and what's going on with it other things it'll do is determine the formation of the earliest galaxies U the earliest galaxies that we expect to be able to see some 15 billion years back in time if we can do that we can confirm or not confirm a number of the theories of how the universe developed from The Big Bang thank you very much do I think you can understand why Communications is his Forte our next speaker is Ken Cox who is currently the chief of our avionic systems Division and he will discuss the onboard guidance navigation and control systems of the Apollo program uh thanks a lot Joe um I was going to State first that uh I had a uh cataract operation less than a week ago so you may see a oneeyed presentation here okay but uh the doctor told me to stay away from Bright Lights oh dear and I didn't I didn't realize this but anyway if I squint uh there's reason uh when I went through the U uh guidance nav and control from a uh command service module CSM and from a lunar module um it brought back the fact that there are a hell of a lot of acronyms that I had forgotten and uh it took a while to start picking some of them back up I would like to I would like to say this that I'd like to give appreciation to the fact that uh Norm Sears and and Russ Larson from Draper lab helped me put this this presentation together and uh back in the Apollo days 20 years ago it was called MIT instrumentation lab and they had a major responsibility as far as the development of the onboard uh uh guidance nav and control let me go to the first uh next next slide please okay what I intended to do was to was to religiously follow the assignment given called how did we get there but I quick ly decided I had enough material that I couldn't explain how we got back okay and I followed I followed your your instructions Joe um what I want to do is uh I've got about um oh seven or eight slides just to talk off of and I wanted to avoid uh giving you equations of motion or detailed descriptions of hardware and try as I go to give you some of the human element because it it it's really interesting if you were involved in a project like this many of the things that that that have happened um I'll talk about the lunar Landing Mission phases but because Ron Barry and some others have preceded me I'll skip over that rather quickly and then uh describe what the equipment was on the lunar module and the Command Module and what I decided to do was um I asked myself well what were some of the really significant uh operational and Technical events that happened on the way to the Moon where uh I would finish my particular cycle as far as once the lunar module touched down on the moon and I came up with four areas that I thought were were important in the guidance nav and control area uh one was the fact that uh the onboard uh spacecraft with the U scanning telescope and the seant had the capability to do autonomous Nav Now as you as as previous speakers have talked about uh the ground the ground system was the primary system but there was the capability that if for some reason the communications gave out was there some way to get back self-contained and that capability was built in um the second uh item that I will discuss uh in a little bit of detail is the fact that uh like uh Doug just mentioned Doug Bloom uh in the control area we went through this analog to digital conversion right in the middle of of the project and we ended up that for Gemini and and Mercury the previous spacecraft there were analog autopilots uh analog feedback systems and uh that's the way it started out on the Apollo program North American was responsible for the command service module and they had an analog SCS system stabilization and control system Grumman was responsible for the analog flight control system or analog autopilot for the lunar module and we went through what we call a block two exercise and decided to go with digital control systems and it was a fairly significant decision at the time um and so what I'm going to talk today is more of the U primary system as opposed to the backups the third significant event that that I'll talk about is that uh I went back and reviewed a lot of the work and without a doubt the final powered flight phase of the lunar module descent propulsion system where we were headed toward the moon but with the with the big engine on if you will uh and how that got developed was indeed a a significant contribution and I'll talk a little bit about that and then finally uh you get showed an awful lot of equipment but uh how the crew how the astronauts worked with the the guidance nav and control system uh uh and how that uh uh interface was developed between the man and the Machine was really a challenging uh uh area and many many people have contributed as far as the work that went on okay next chart all right I think I'll go through this one rather quickly um I've got the the mission phases here but most of what I'll talk about today start from say the uh translunar injection where we actually get out of the orbit of the U Earth where the Saturn has taken us and we're headed toward the moon and as we head that way in general there were either two or three midcourse Corrections that were planned as I as I recall trans lunter Corrections um once we get into the lunar uh orbit uh with a um Loi lunar orbit injection which I think has been talked about also um then we're around the moon in a certain time period and at the bottom uh is is a picture that shows uh uh going down where um once the lunar module the limb and the command service module decouple and the command service module stays in orbit around the Moon uh the lunar module has an injection slight burn and then it coasts for a long time and then we finally get to the final powered flight landing that I'll talk about in more detail and that's where I'll stop as far as any comments on the um guidance nav and control system now there's a awful lot of work as far as what did we do to to design the control system when you lift off from the moon for the ascent and the Rendevous that went on and so forth and coming all the way back to Earth and and re-entry and so forth but I won't cover that area okay next chart uh this just tries to show what some of the major equipment was for the uh onboard system in this case we're talking about the Command Module or the command service module really um and it turns out that the Optics which gave us some of the autonomous navigation capability consisted of a scanning telescope and a Sextant and the functions of aligning the platform um which was a three gimbal platform um using the the Optics was part of the function as well as the navigation sightings um the computer um I think I heard Ron say that there were not enough memory but when we started the project I think we started with 24K memory and we eventually went up to 36 and 36 was a lot of memory right and surely we wouldn't run out wrong we went through the Black Friday as as Ron said and cut all those elements out that had been developed and so forth and uh uh just to show that history we always learn you know we went to the same thing on the shuttle and we ended up with 64k so surely that would have been for the shuttle and that was before we double them