Gemini 5 Technical Debriefing, Part II, 1965

22 Authority: NW 91526 GEMINI V j Technical Debriefing Part ~I_I__________________ CLASSIFICAT:ON CHANGE o_ ----.......,,_~ s:..;;...:1:...::...,::.1-=-= c L~A o_~ s F E By authority of • o I G !>- .2. -/ - ? "'t.. Chanied by C'~ ~ , Date NOV 2 0 NOTICE: This document may be exempt from public disclosure under the Freedom of Infor­ mation Act (5 U.S.C. 552). Requests for its re­ lease to persons outside the U. S. Government should be handled under the provisions of NASA Policy Directive 1382.2. THIS MATE ,-IAL CONTA INS INF09'MATION AFl"£CT ING THE NATION"L DE FENSE OF TH t: U NITED STATES W ITHI N THE MEANING OF TH£ ESPIONAGE LAWS . . TITLE 18. U .S.C. SECTION 793 AND n• . THE T9'ANS­ MISS ION OR REVELATION OF WH ICH IN "NY M"NNIEl'I TO AN U N ....UTHORIZ£D P'E ASON IS PIIOHIB ITE D BY LAW. GROUP 4 DOWNGRADED A T J YEAR I N TF RVALS CECLASS IFIEO AFT£9' 12 YE...,,-5 973 l COt~FIDEt~TIAL PRELIMINARY GT- 5 FLIGHT CREW DEBRIEFING TRANSCRIPT PART II Prepared By Spacecraft Operations Branch Flight Crew Support Division September 2, 1965 This material contains information affecting the national defense of the United States within the meaning of the Espionage Laws, Title 18. U.S. C. Section 793 and 794, the transmission or revela­ tion of which in any manner to an unauthorized person is prohibited by law. Group 4: Downgrade at 3 year intervals Declassified after 12 years co~~FIDEt'4TIAL (' PREFACE This preliminary transcript was made from voice tape recordings of the GT- 5 flight crew debriefing conducted August 30, 1965 thru September 2, 1965 at the Crew Quarters, Cape Kennedy, Florida . Although all the material contained in this transcript has been edited , the urgent need for the preliminary transcript by mission analysis personnel precluded a thorough editorial review prior to its publication. Errors in this transcript will be corrected as soon as possible and an official transcript will be published at a later date. This document contai ns a transcript of the second part of the total debriefing. A prel iminary transcript of the first part was publi shed on September 1, 1965 , and it contains the crew' s description of the mission from an operati onal standpoint. ;CAts4flOEt!!IIAb TABLE OF CONTENTS Paragraph Page number 8.0 SYSTEMS OPERATION 8. 1 Pla t f o:rm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . • • 1 8. 2 O.AMS •• ..... . ....... . . . ......... . . . .....• .. •. •• ••••• 16 8. 3 RCS •....... . .. • ....•..... . . •. .••. .. .... . • .•••••• • • • 47 8.4 Environment al Control System ·•· •·• ··•·••· · ··•••••• • 54 8, 5 Comm.1.lllications .... . . .. ............... . .. . ...••••••• 66 8. 6 Electrical System ... . ... . ......................... . 80 8. 7 Computer ..... . .. . ... ... ......... . ........ . .. . . . ... . 82 8. 8 Cr ew Station ....................................... 90 9,0 OPERATIONAL CHECKS 9.1 Apollo Landmark Identification • ••• •·••·••·•••• ••• · 132 9. 2 Cabin Lighting Survey . . . . . . . . . . . . . . . . . . • . . . . • . • . • • 146 9. 3 SPADATS Tracking Check . .. . .. . .. . . .. . . . . .. •.. • • . . .. 147 9.4 UHF Antenna Pattern Test ..... .. . .. .. . .....••.•.••. 147 9. 5 Thruster Illuminat ion Checks ........... . . •....•••• 148 9. 6 Dual Command Transmitter Test ....... . .. .... ...••• • 148 9. 7 Radar Test s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . • • . 148 9. 8 ID1 Evallla. tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . • . 150 10. 0 VISUAL SIGHTINGS 10. 1 Powered Fl ight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 10. 2 Orbital Flight ...... . ... . ....... . .... .. ....•• . .• . . 153 10. 3 Reentcy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172 11.0 EXPERIMENTS 11.1 Visual Definition of Celesti al Objects (D- 1) , Nearby Object Photography (D- 2) , and Terrest rial Features (D- 6) ••···· • ·•·• •· ··• · • •• · • · ··• •••• •• •• • · 210 11. 2 Cel estial , Space and Terrestrial Radiometry ..•.••• 222 11. 3 Synoptic Ter rain (S- 5) and Weather (S- 6) . J?rl.otography . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . • • • • • • • • 228 11.4 Visual Acuity and Astronaut Visibi lity (S-8/D- 13) and Vision Test (M- 9) .......... .. ..... . ......... . . 233 11. 5 Electrostati c Charge (MSC-1) .......... •• . . •.•• • •• • 242 11.6 Zodiacal Li ght Photography (S- 1) .... .. .......• •• .• 243 11. 7 In- flight Exer ciser (M- 3) ........... . .... . ........ 243 11.8 In- f l i ght Phonocardiogram (M- 4) ••••··•••••••· •··•• 244 11. 9 Cardiovascular Reflex Conditioning (M- 1) . •••••••• • 244 11. 10 Cloud Top Spectrometer (S- 7) •·•••••··•••·•• • ••· ••• 246 11. 11 Miscel laneous ............. . . . ... . .•...... . ...••••• 248 CQ t-4 F-1 DEt-4TIAL 12.0 PR.EMISSION PLANNING 12.1 Mission Plan (Trajectory) .. . .. .. .. ..... .. . ......... 255 12. 2 Flig}lt Plan .. ... .. ... ... . ..... . . ..... .. . . . .... . .... 255 12.3 Spacecraft Changes . . .. .. ..... . ..... .... ... . . .. .... . 255 12.4 Mission Rules . . .... . . . ..... ........... .. ........... 256 12. 5 Experiments .. .... . .. . . ...... . .. ..........•......... 256 12.6 Training Activities . . .. . .. .. .. .... .. . ....... ...•.. . 257 MISSION CONTROL 13. l GO/NO GO ••. . ... •. ....... ... ... . . . . ...... •• •. •• • ... . 261 13. 2 FLA and CLA Updates .. .. ....... .......... . ..... .. . .. 261 13. 3 Consumables .•.. . .. . . . .. ... ....... ..... .. . . ......... 261 13.4 Flight Plan Changes •. .. ... . . . . ... . .. ....•.. ... .. . •. 264 13. 5 Systems .• •. .. ... . ............ .. . .... ..•.•..•• . . . . ..267 13.6 Experiments Real - Time Updates .. .. ........... . . . . .. . 268 TRAINING 14. 1 Gemini Mission Simulator . . ........................ . 270 14.2 LT\T , DCPS • , . ... .... . . . . .• .. . .........•• . .••. . • •. .• • 284 14. 3 MAC Engineering Simulator •• • ••·•·••· • · •·• ••••••· • •• 285 14.4 Centrifuge ... ...... . ... . .. . ........................ 286 14.5 Translation and Docking Trainer ••• · •····•·• · ··•••·· 286 14. 6 PlSlletaritllD. .. . . . .. . . . .. . .... . .. ....... . . ... . ....... 288 14. 7 Systems Briefings . .. ........ . . .. .. . .. . . ........ . . . . 292 14. 8 Flight Experiments .. . .. . . ... . . .... . . .........•. .. .. 293 14.9 Spacecraft Systems Tests . .. .... . ... .. . ............. 294 14.10 Egress Training ..... . ..... . . . . . . . ...... .... . ....... 296 14.11 Parachute Training ......... ... ... . . .... .. .......... 297 14.12 Ia.unch simulation ............. . . . . . .. .. . . .... ..... . 298 14.13 Network Simulation .. ....... . ... .. ... . . . ...... . ..... 298 14. 14 Reentry Simulation . ... . ... .. ...... .. ... .......... . . 298 14.15 Simulated Network Simulations . . ... . . ....... . ...... . 298 14.16 Zero "G" Fligh.ts ............ . .. . . .... . . .......... . . 299 14. 17 Flight Plan Training ... .... .. . . . . . . .. .............. 300 15.0 CONCLUDING COMMENTS 15.1 Crew Qu.arters .... ; ....... . .. . .. . .. . . .. •.... . .... .. . 30 2 15. 2 Physical Training and Aircraft Flying . ... ..... ..... 303 15.3 Sea I.a.b . . .. ........ ... ....... . . ... .. . . .. . .... .. . ... 304 15. 4 Watches and Clocks . .. . .. ....... . ....... ...... .. . ... 304 15.5 Miscellaneous Discrepencies •• · ··•·• · ·· •• ••••••••••• 306 15.6 Medical Aspects .. . .. .. .. . . . . . ........ . .. .. .... . .... 310 1 8.1 Platform Cooper 8.O SYSTEMS OPERATIONS By day we used standard procedure of finding a zero yaw, which is a little easier to do down at about retro position. The nose is a little bit in the way for determining zero yaw unless you pitch down just a little past nose low in zero­ zero- zero position. When pitched down just a tiny bit, zero yaw was very readily apparent to within a fairly reasonable degree of accuracy, and then ease it right on up. We had lines for the zero­ zero position to give us our pitch and roll on the horizon. This was the regular day alinement. Night was pretty much the same except we 1d get zero yaw by a star, get roll and pitch by the zero lines on the window (or knowing where they were approximately) line this with the top of the air­ glow or the horizon. At that point you'd go into Cage, hold it there at that position until it caged) then uncage the platform to BEF or SEF whichever the case might be, and then to to Plat­ form and Attitude on the FDM and FDI's. Then aline the platform fine aline SEF or BEF by keeping , 2 the needles zeroed. It would slowly gyro torque itself and correct out the small errors for fine alinement. Anything to add, Pete? Conrad Well, I didn ' t hear all of that, but I think the alinement is straightforward. One thlng I had not read in either the GT-3 or GT- 4 debriefings on this subject on out the window alinement was that we have a window gage that you can us1i t hat will put you right on in roll and pitch ancl, of course, for yaw you still have to use the same out the window reference. Cooper One thing that I think that should very definitely training wise be readily available anc. we looked and looked and looked and couldn't fir..d any was an actual scale picture of the left hand wi ndow and the right hand window with what the hcri zon should look like at zero-zero-zero and at retro attitude and at minus 90 degrees left and 90 degrees r ight and at 60 degrees left and 60 degrees right and this type thing. I've never seen an a~tual drawing showing the horizon line on a window a·'ld what i t should look l ike . 3 Conrad Yes Cooper I think this would be a tremendous benefit and shouldn't be difficult to come up with. Conrad If you place your eye so that it goes through the lower left corner of the right window or the lower right corner of the left window and run that eye position right through the front RCS yaw thruster, the lower yaw thruster in the front ring, I guess that's ring A, anyway, you take a line between your eye, the corner of the window and the front RCS yaw thruster, right through the middle of it, and put that line on the top of the airglow or the horizon. Then the spacecraft, and this looks like an excessively nose up attitude, but it's not, you're zero degrees in pitch then the window frame is just about vertical to the horizon and it forms a perpendicular angle. Cooper The inside edge of the frame . Conrad The inside up and down edge of the window corner makes a perpendicular angle to the horizon and you can use that as a roll gage. If you set it up 4 that way that platform isn 't i n roll or pitch. off 4 or 5 degrees Cooper So, i t really looks like, when you fir3t start lining it up, it appear s to you that f ::-om the left seat that you ' re actually rolled l eft , Conrad Yes, that's right . Cooper And f r om your seat it would look l i ke j t actuall y r olled right. was Cooper It doesn ' t look horizontal at al l, but that ' s due to the fact t hat you 're sitting off by thi s offset . Conrad One other thing that you might say about platform alinement is that if you ' re not on in roll and pi tch, mainl y roll, t his really will ea t you up in alinement time . Cooper Roll and yaw are you can be off a out. t he bad errors creator:, . l ot i n and it' 11 corr ec:t Pitch r ight Conrad Not if the other two (roll and yaw) are off . Cooper But if you 're off in roll and/or yaw th€n it really takes a long time and its real rcugh . 5 Conrad You don't want to be deceived by the fact that the needles are holding in the center pretty well. Cooper That's right, one thing that we found when we were going through this real, real long platform alinement prior to getting all l i ned up for retro­ fire was that we had the needles all alined, t hey were sitting all glued out . But you have to s i t there with them for a little bi t glued out. They sit there all zeroed out, it looks like everything was all alined and al l of a sudden yaw begin to ease off quite a bit showing that we weren ' t alined. Conrad At one time we went to Orbit Rate when we had not pulled the yaw all the way in and, boy, it showed up in roll as we started moving around. Cooper Orbit Rate and Horizon Scan. Conrad I mean it shwed up in the roll axis . Cooper Oh, yes. Right. Conrad You have to take t he time and be careful with the platform alinement, no doubt about i t. ° CSf*fDEt◄ TIAl 6 , Cooper And i t takes t ime to do it and do a job on it . r ~ally good Modes . The only thing I can say about that it takes an excessively long tim1; Cage is to Cage . Conrad I 'll comment on this even though we d:i. dn't get a chance to do the rendezvous, but even in simula­ tion, it was apparent and the l i ttl e bit t hat we did in flight caging the ~latform, getting ready for alinements and t hings l ike -;hat, it was very time consuming. I think tha·; you could find use for a fast slave cycle . Cooper Very much so. Conrad Fast Cage cycle is what I should say. I 'll say it's a luxury item but it sure could be helpful. Cooper SEF and BEF worked just like advertisEid . SEF for fine aline and small- end- forward, BEF for reYersing your phase angles so that you ' re still steering to and fine alining blunt encl forward. Conrad J i m and Ed made the comment that t hey never alined BEF, that t hey always alined SEF. We alined SEF normally through the flight and when ,:e were ready 60 ►◄~ ~ 7 Cooper Conrad Cooper Conrad Cooper Conrad Cooper Conrad to retro, we wanted to save as much fuel as possible, so we alined BEF and I think alining BEF is easier than in SEF. Yes , I think you can tell yaw better going backwards than you can going forward. Yes. I don't know why, maybe it was just psychological. I agree with you, I really think you're right. I think you can tell it better. It streams away from you a little more . Yes. It was easier to pull in in yaw. I thought it was a little more comfortable feeling . I enjoyed the riding around alining the platform BEF much more than when we alined it SEF, and I felt we were closer to being on most of the time when we pulled it in in yaw. Of course, we had a little better control system there, it does help. Yes . Mt ◄ FIDE►~TIAL • 8 ~NftDE~~TIAt·,_ Cooper I think either way (SEF, BEF) is good, both worked very adequately and it just depends on which way you want to aline for what you ' re going to do . BEF is certainl y at least as acceptable as SEF. ORBIT RATE was not bad off at all . We didn't have any l arge errors in it due to t he fact that we had more nearly circulari zed our oroit from t he burns that we did. Conrad We were about at 171-60 at that time p<=:riod. I don't know what t hey had picked as an orbit rate number at the end finally for the REP. Cooper We were about 107, 166. Conrad Yes . I was really surprised with how ,..,ell the platform stayed on after just t aking a quick look at zero- zero- zero, not even trying to ali ne these. We just passed freely through this in dr ifting flight and uncaged the platform right into Or bit Rate, and it didn't get off five or ten degrees in any of the three axis . Cooper For about 20 hours . 'i0 ►~FIDE►~TIAL 9 G©t◄ FIDl!~~TIAL Conrad Cooper Conrad Cooper Conrad Cooper Conrad ,, Cooper Yes, for about 20 hours that we drifted around. It was finally off the most in roll. It got about 15 degrees off in roll. Orbit Rate worked very well. Other than inertial work, I just didn't see any big advantage in free. You'd still think in terms of the local horizon up there most of the time. Yes . We just never had much occasion during the f light to use FREE. Platform displays . Bal l operation through the poles was just fantastic! It was so smooth. The only way you could tell that you were going through a pole is you could see the roll index, vehicle is on the roll gimbal, flip . Yes. This is something we had trouble finding out, whether this was the case or not and we deliberately ran several specific checks of this. <!rJ~~FIDEt~TIAL 10 Regardless of which way you approachec. it from, whether you approached i t fast or slm.- or whether you 're going through the 90 or 270 pojnt on the ball, you can go right smack through the middle of it, you can sit right in the middle of it, you can move up or down, r ight or left and the ball doesn't jump, doesn't j itter, doesn't do anything. It's just beautiful . Conrad Yes . Cooper We did a burn right through each one of the poles . I think the controls are pretty simila-r to what they are in the simulator . There are t wo exceptions, one of which I think i s valid and which I think may be influenced by the fact that we had a lot of s low degredation in ou:~ OAMS system. I thought that the PlJISE system in the spacecraft had a lot less torque, a reasonable amount less torque and it got a lot leBs, as we went along it got less and less and leHs . Conrad Yes . Cooper But even i nitially, it felt like thP- PlLSE system 11 had less authority in the spacecraft than it does in t he simulator. On the other hand, I felt the RATE COMMAND system had a heck of a lot more authority in the spacecraft than it does in the simulator. Cooper That RATE COMMAND just flat snaps you in. In the simulator, when you come around in RATE COMMAND and you let off it will go through 5 to 10 degrees. You have to let off on it 5 to 10 degrees early. By golly, in the spacecraft you didn't have to let off even a degree early. When you let go, it stopped right there just like you put on the brakes. Conrad Yeah. It was good and it was tight. Cooper It was so tight that you almost had to - - Conrad That was OAMS Rate Command. Cooper You almost had the feeling that the OAMS Rate Command was almost bending the Adapter Section. I t had such high torquing rate. Conrad On day 2 and 3, our OAMS system was working completely correct. I was extremely impressed 12 • FCSD REP Cooper Conrad Cooper Conrad FCSD REP Cooper Conrad with how nice a control system i t was. We made several maneuvers using this control Eystem and didn't have any gripes on that system at all . As Gordo said we were really impressed wjth the Rate Command system. When you turned around 90 degrees in crder to get rid of the REP, did you use the 8-ball ? Yes. FDI 's are on this Gimbal flip bus i ness too, you see . They do that in the trainer, but they were steady as a rock in the spacecraft. Yes, we used the FDI's for t he fine al ine . Al­ though to get there we used the 8-ball. We had trained to use the IVI' s . That 's right. We used the IVI 's, not t he FDI' s . We used t he IVI ' s as the real fine measure of being l ined up. We used the FDI 's too. You can use anything in the spacecraft. 13 Cooper .. Conrad Cooper Conrad Cooper Conrad • You can't use the FDI 's or the 8-ball as a reference in the mission simulation because you have this gimbal flip which just gives you fits . We didn't use Rate Command very much, mainly just for the burns. In fact, t he burns are the onl y times we used Rate Command. I used the Direct system several times and I thought the Direct was really good. It was good and crisp and you had good authority with it. I had the impression that the spacecraft was a lot more stable vehicle in Di rect than it was in the simulator. Tmt' s right. In t he simulator you tend to sit there and go too much and go too much. When Gordo'd stick a shot of Direct in to go someplace, it never showed up in another axis. An equal shot i n the other direction would stop it r i ght now. Yes. The effects momentum of the spacecraft didn ' t seem to be as great in flight as they were i n the ~f:HDEt◄TIA ~ 14 "t OMFtDE~ ◄ TIAL simulator. You didn ' t have to lead a:, much. Cooper That's right. The Direct system was a much more precise system in the spacecraft than it i s in the s' mulator. Conrad I thought it was quite easy to fly, but there's no doubt about it, boy, that Rate Corrunand eats up the fuel . 15 • Cooper Conrad Cooper Conrad Cooper Direct uses quite a bit of fuel also. We did use a little fuel t hat one day. We were doing so many experiments in a row that we had to very rapidly get the spacecraft back to a zero­ zero- zero or a pitch down 30 posi tion. When you track one of these targets and come through the nadir and keep on going, boy, you're really smoking towards a rearward direction. You're sitti ng i nverted BEF. That's r i ght, you ' ve got rates built up going away from you and you 'd have to use Direct to stop those rates, get yourself moved all the way back up here and stop them again. Maybe it'd be so tight that you'd use Di rect to get down and start on it, and then switch to Pulse and track in Pul se and then r i ght back up and start doing something else. Well, we di d eat up a lot of fuel that day, but we got everything done that day. We hit darned near all targets. Di rect i s a real responsive , real fine way to maneuver. 60t~Fl0Et.t:tAt 16 Cooper Conrad Cooper Conrad Cooper 8. 2 OAMS Cooper Cooper •i Q:Mf~Cf1stIIAla .. Platform controls were very straight fc,rward. I thought they all functioned as expected. The Platform took the full 25 minutes to go through the fast heat, and the first time on it was really cold and took another 3 minutes worth before start of the Cage Cycle. After that, it seemed to stick right around 25 minutes to get the platform up and on the line and start into Cage. Right now, I've got extreme confidence in that Platform. I really think it does well. '.Ihe platform did an outstanding job during the entire flight. I t sure did. We fired the OAMS on the pad and it was mushy. You couldn't hear them fire just gas mainly, About the third round of firings however, you could really feel them fire off, they were all good. During flight the OAMS started out very good and in about the third day began to degrade. ~:he f i fth day ~liUiiAL 17 i s when we found the two thrusters that were not operating correctly. Conr ad 'Ille number 8 thruster was working real good when we found that the number 7 thruster was out. So we shut the system down again and had a big talk with Houston about this. We went one more revolution and they gave us some tests to perform on 7 and that 's when we di scovered 8 wasn ' t working. Conrad 'lwo of them quit, within an orbit of one another. Cooper We had already run complete tests on it and number 8 had been working on the previous tests and quit on the next one. 'Ille story of the old OAMS inflight system was that gradually as the days went by there was more, and more that went wrong with it unti l f inally at the end we had less than half the thrusters left and they were pretty bad. Conrad I realized a couple of heater blankets were probably out on the OAMS system, but I'm still convinced unt i l somebody convi nces me otherwise, that the thing that shot the OAMS system down, was the decision to turn off the OAMS heater. I had ques­ ioned the decision in the air to only point that 18 I could. I didn 't think we were in that much trouble for electrical power. I still think it was a mi stake because I think even with a couple of blankets out, if we'd have kept the ,3ystem warm wi th the rest of the heaters, we'd have never froze them up. Cooper 'llie thrusters themselves were actually ·vorki ng because you could actually get a glow off of them. There was a little bi t of fuel or oxidiier coming out of it and burning , but it wasn't getting the proper amount of mi xture ratio. Conrad Now, they could have been dirty. That :ould be it, but it was purely in the valves i n the thrusters themselves because they were putting out thrust even at the end. I f you wanted to hold it i n full D:Lrect wi th 7 and 8 circuit breaker engs.ged, you were getting wet fuel thrust. Cooper Yes. You were getti ng a little wet thr~st. Conrad let's go into how the whole thing occurred. We had shut the heat er down a long time ago and we really hadn't agreed wi th that, but there wasn't much we could do about it. We were i n the mi ddle , 19 of doing experiments on the fifth day, and we had had a little trouble alining the platform. What was happening, apparently was the number 7 thruster was getting cranky, but we also knew we were vent­ ing hydrogen and we knew this because we were getting some torqueing out of that. At the t i me Gordo was having trouble ali ning the Platform, we thought it was because the hydrogen was venting. Finally Gardo said, "There's something wrong with t the control systems. " Once we deci ded there was something wrong wi th the control system, that 's when it went just like back i n the simulator. We shut everything down, went to Direct, thought about it for a second and turned off all the circuit breakers , turned them all back on one at a time, tested all of the thrusters and, sure enough, when we got to number 7, it was out, completely out. Conrad So then I tri ed secondary ACME bias power. We tried the seconday yaw and the secondary attitude drivers with no effect so we were relatively as­ sured that something had happened in either the hand controller or the fuel was not feeding. We decided to power down r i ght there , which we did, and we advised flight of what the problem was. £ 8.M&HW~Jl~i I 20 think that's about the time we really decided the s canner wasn' t any good, or had we already tol d them about that? Cooper Yes. We 'd already t old them about that. Conrad Yes, you ' re right. I know what it was. That's when we discovered that the voice tape was out. We were right i n the middle of several experiments and it occurred approximatel y like 16:30:54 on the f i f th day. We reported to Houston that the voice tape was out, the number 7 yaw L~ft thruster was out and that I had turned the OAMS heater back on. I was suspicious of that all the ·;ime. That's when they called up and gave us this m:i.nimum power down. Why did we go i nto that? They had us power down everything. Cooper At about the same time that we came up with this, they came up with this idea that the hrdrogen was boiling off so fast that we were going t o be out of hydrogen by about the end of the f i fth day at the rat e we were goi ng i f we di dn't power down and stop the usage of i t . .iO~~FIDEMTfffl: • 21 Conrad Cooper Conrad FCSD REP Conrad Yes. That's when we came around on the next revolution. 'Illey had us fire up everything again to take a look at i t and that's when we found out number 8 had just gone down the tubes too. But number 8 was still givi ng us something; number 8 was stil l burning, but it was burning off mi xture. You could see a flame. You could see a glow out of it. You couldn' t hear it like you could hear the other thrusters, but you could see lights on the ni ght side so you knew something was coming out. 'Ille drivers just weren't openi ng all the way or some­ thing. The fifth day at 16:30 is the first problem you had with the OAMS, is that right? No, earlier. When we first powered the system up, we were having trouble with that very f irst platform alining and we felt we were having some hydrogen venting problems. 'Ihat's when we drifted way off, and Gordo said, "'Ille Pulse system isn't going to hack this hydrogen venting. " He went t o Di rect and blipped the yaw l eft thrusters. • 22 All kinds of garbage came by the spacecraft. It looked like we blew a whole bunch of junk out of it. I remember distinctly seeing gold balls. Cooper Great bi g balls of l iquid. Conrad So it must have been raw fuel . Something at this time wasn't working right, but I guess number 8 was putting out full thrust and number 7 was still worki ng but not all the way. Now mayb<? right then and there if we'd have really worked that system over; fired all the thrusters in Direc1; and a couple of good healthy loads throug it ,., and put the heater s back on the line, we might have sal­ vaged thew vaged the whole system. It must have been right at the point of freezing up. Cooper This was early i n the fifth day. .£:Obi:EIOEttllAL 23 Conrad We didn't hit the direct thrusters long enough to heat them I don't think. I do distinctly remember saying to Gordo "We blew all this junk out of there. " Conrad We' d never seen anything like that before and we'd been up there 5 days and seen all sorts of things . We could see liquid oxygen when we vented it, if we vented i t under the right light conditions . We could see when we vented hydrogen under the right lighting conditions. It would all float by the spacecraft and at low sun angles, either at sunup or sundown any one of these quantities, ECS o2, CRYO o2, or RSF hydrogen, you could see it come whistling by the spacecraft. We were continually floating around in these old silver balls of either hydrogen or oxygen. Cooper Okay, well that was pretty well the background of what happened. Some thrusters that had checked out good would subsequently check out bad or be completely inoperative as the days went by. So finally we wound up with maybe half of the total OAMS thrusters still operating properly. 24 Conrad • We had some thrust remaining in every axis but yaw l eft. We had some in yaw left if you just wanted to dump raw fuel overboard. I don ' t know whether it was fuel or oxidizer. Cooper Generally, what we'd do is roll and pitch to get our yaw left . Conrad I f we were tumbling and wanted to damp we just waited until we translated into the right axis in which we had some authority. Cooper The one axis that always seemed to work pretty good so far as control authority was pitch. Conrad Yes Cooper Pitch up and pitch down seemed to work reasonably well all the time. Conrad Yes . I wonder i f that had something to do with the pitch thruster lines on the manifold being close to the source. Pitch was always good. Our trouble was mainly coupling in the yaw thrusters both right and left. Cooper Source pressure was easy to monitor. SJurce temper­ ature we could monitor and it was too CJld. Conrad Cooper Cooper Conrad Cooper Cooper Conrad Cooper Conrad 25 It ran down in the 48 degree area. It showed that it was running too cold. That's why we questioned turning the OAMS heater off, Regul ated pressure was fine . Right on the money. Propellant quantity seemed to read r easonably good until it got down towards the end. At that point (from about 10 percent on down) the propellant quantity just went on down to the bottom of the scale. It was reading below zero and yet ground readouts indicated OAMS propellant quantity remaining. Monitoring of OAMS propellant r emaining onboard information was fairly good. Yes. I thought we were fairly close. Gr ound i nformation agreed fairly good with onboard information in general. The whole OAMS systems got to be reviewed. I think that they think we wasted a lot of fuel and I think that on day 3 we probabl y were a little overgenerous with our fuel usage. But I ' m still ret◄ FtE>Et.~TIA ~ I 26 Cooper Conrad Cooper Conr ad COt--1 FIDEt◄ :rIA~ ,; convinced that because we went so long with the OAMS heater off that we were not burning a nominal fuel to oxidizer ratio. Yes . Even though we were in a rush to get a lot of ... these things done, I was still extremelr conscious of fuel usage . Although I'd used Direct to get i t started, I wouldn't just fire all the way around in Direct input, let it coast around, a~d then stop it right there. Yes. I never saw fuel usage in the sim1lator like we saw in flight . I t just seemed to go down very rapidly on the gauge during that one period of time. And yet we went night after night all night long in Horizon Scan or in Pulse and would hardly use any fuel at all. As a matter of fact, the ground gave me the figures. This was when we were ::unning all ni ght long in Horizon Scan so that we had a nice reference. They said "You' re using about 2 pounds a night. 11 Now, that seems like a r easonable amount for what we were doing. • 27 Cooper We were using it for Attitude Hold and for getting pictures and to get through the day side. Conrad Oh Yes. We never used Rate Command except for the maneuver burns. Cooper We were tracking the missile using Diredt. get on it in a rush so I went to Direct. Had to Conrad Cooper I questioned propellant quantity prior to lift­ off. It was 87 percent at lift­ off, I thought we were supposed to be 100 percent on the gage at lift­ off. I thought we had propellant quantity loaded to the maximum? Well, they said we were about 50 pounds under. Conrad Yes, they said we had about 50 pounds less fuel than we were supposed to have. Cooper We asked them about this before we l ifted off, Cooper At about 4 or 5 minutes before lift­ off, them about this. we asked Conrad We got a "We ' re checking" and that's the last we heard from it. And off we went . 28 Cooper So then we asked again when we wer e in orbit, "About this under load on GA.MS fuel" . I suspect t hat something was fouled up because we didn ' t get a full 0AMS load. That was pretty bad. Cooper I think monitor ing onboard of propell~mt r emaining t o compl et e the mission was pretty good. The fore­ cast fuel for missi on completion of GE,mini V ought to be reviewed because somebody didn ' t quite come up with the right fuel figures . Twenty- six percent remaining after the REP would not havE been nearly enough to have ~one the r emainder of the mission. Conrad Yes . I t hi nk t hat in computing the a.mount of fuel used t o perform a maneuver, they figure out how much to get the r ates going but they must s top there. They must not f i gur e how much fuel it takes you to . get back to, say, zer o- zero- zero. Appirentl y t hey assume that whenever you get done with a tracking maneuver, you j ust drift to get back to zero- zero­ zero. Over the U.S. we had maybe 6 or 7 minutes be­ t ween a 30 degree pitch- down target to the next 30 degr ee pitch- down target . You ' ve got to t r ack it all t he way through, bing the spacecraft all the way back up and then go to and track the next target . 29 Cooper And stop your rate at the back. Conrad As a matter of fact, that's about twice the fuel usage. They may take this into account, I doubt it. They're very conservative on their estimates . Cooper Selector controls and switches were all right. Attitude controller was fine . Maneuver controllers . ( We had every intention of checking the right one and we never did check it because of other problems . Inflight malfunction irregularities we've already covered pretty well. Cooper Attitude Control Modes, Rate Command was excellent. Reentry Rate Command we never checked. Conrad I don't even think you need it . Cooper And I think it could be removed from the spacecraft as far as I 'm concerned. I never used or need it on the simulator. I never liked it. Conrad Pilots aren't going to tolerate these higher r ates . They will damp before these rates are reached. Cooper Direct is a good mode. There' s nothing at all wrong with Direct . I thought it was much crisper, much crisper in the spacecraft than in the simulator 30 Conrad Cooper Conrad Cooper shows that it is . The Pulse mode was very economical on fuel and I felt that in the sinru.latc,r you had a little more authority than you actually did in the spacecraft . The spacecraft had slightly less authority in Pulse than the sinru.lator does . Inci­ dentally, you can use Pulse just for a month of Sundays and never see the fuel go down on the 0AMS gage at all. You can use Pulse all day long with using little fuel usage. Horizon s can, the primary Scanner was inoperative as was stated e3.Tlier. The Secondary Scanner worked fine. The sca::mers, I think, operated quite satisfactorily. We had a lot of scanner dropout in the primary and eiren in the secondary. We had some dropout in the :iecondary when we first were going in and out of i;unlight areas . But then it seemed to work allright. Horizon Scan Control Mode worked fine . Real good. It's a loose mode but it still works fir..e . It's got wide limits on it of course, -which i s okay. The mode itself works fine. There was some­ thing really fouled up in the platform rnode. It didn't work at all like it's supposed to. The platform mode is supposed to be plus or minus 5/loth of a degree. If it was plus or minus 10 degrees I 'll eat my hat . .. • Conrad Cooper Conrad FCSD Rep Cooper Conrad Conrad Cooper 31 I thought it held to about a degree and a half . Not in yaw, you remember. It allowed yaw to wander off by probably a good 10 degrees there. Remember it allowed right yaw to wander off by about 10 degrees and just sit off there in right yaw several times. It wouldn't even bring it back. Yes. That was the trouble. Do you think this had anything to do with your con­ trol problem? W-ell, it may have been. It may have been that con­ trol was somewhat intermittent right there. I don ' t know, but it might have been. But Rate Command sure worked good using those same controls. Yes. I suspect that being the first time that it was cranked up since spacecraft number 2, it may not have been tweeked as well as it could have been. It certainly didn't work like it did on the simulator, I 'll put it that way. It didnlt work properly, and it was no good the way it was. We never used it after we originally tried it out and after we 1d tried doing this one burn on it to see if it would hold. The one that it did hold on, our first perigee adjust, it held beautifully. During the next one, it got so bad it wasn I t any 32 Cooper Conrad Conrad good. Ther e again, it might have been a f unction of the thrusters going out. In any event, I think that 1 s an error ,;hat somebody needs to look i nto. I ' m not sure that pl atfor m mode is doing what i t should. I know that , t heoretically, • and by t he diagrams on it and the limit s that it ought to be a very precise control modE!. Spacecraft separation at SECO + 20 couldn ' t have been better , just fine. Translat i on per igeE! adjust went like cl ockwork. That was our fir st r eal burn and I thi r.k we got something like 9. 6 f t/sec on t he IVI ir.stead of 10 .0, but t he burn wasn ' t that crit icaJ . I checked accelerometer bias and it seE•med like the accel er ometer bias incr eased l at er in the f light . I specif ically checked it f or the REP end it was okay. I 1d just set up zer os in the wirdow and went to Catch-Up and they stayed zero for 3 or 4 minutes or longer . So that satisfied me. I checked it l ater on in the f light and I don ' t think we r an more than a minute and we clickEd up a f oot per second on the fore- aft window. That can be checked on the tape . In the beginning it was entirely acceptable for the REP. 33 Cooper I think we had some bias, just how much I don ' t lmow. The timing of the translation was fine , updating was fine. Operations and checklist were okay. Computer usage, okay. Conrad It was easier to make a burn on the simulator that had no up-down or left and right in it than it was in the spacecraft. Gordo did a real good job of tracking on every burn and I didn't see it wander hardly at all. Cooper And all the IVI ' s would be zero. Conrad And all the IVI 1 s would be zero, but we'd have .4. of 10 a foot in one axis and ~O in another. Conrad 8 Yes. The worst cross- coupling, we had 10 in one axis, and when we burned in the platform mode, but we were checking that. It could have been accelero­ meter bias again, or, the spacecraft is more sensi­ • tive to picking up up- down and l eft­ right velocities than I thought it was . Conrad Gordo did a real good job of tracking. He tracked as well as he did in the simulator and we never had this show up in another axis in the simulator. Cooper It would be zero , zero, zero in the simulator. Conrad It was hardly worth my time checking address 81 and 82 in the simulator because I could just tell he 34 wasn't going to have any velocities in there , and very seldom did. But we never failed t o have fairly sizeable ones , like fa and fo fps, in another axis and I'm not quite sure how it got therE·. I guess the spacecraft is extremely sensitive . If you ' re going to make pr ecise burns, you I ve gotta really burn precisely and i f you want to take out the errors , take out the address 81 and 82 errors so that you don ' t introduce anything else. During the difficult ren­ dezvous maneuvers, you have to plan on more f uel usage because you're going to have to take it out with the up- down thrusters . Cooper I think what you ' re going to have to do is stop short of burning off all your forward or aft velocity, particularly the forward velocity, and then use the canted thrusters to burn off the right- Left and up-do,m and that will take out part of the remaLnder of the forward velocity. If it hasn ' t taken it all out , then bleep out the rest of the f orward . I think that 1s the only way you can do it if you want to burn them al l t o zeros. I don' t believe you can t r ack any more precisely if you keep all your IVI ' s zeroed right down the money. If you burn it off and stop just at the right time so that everything should turn 35 Cooper FCSD Rep Cooper FCSD Rep Cooper FCSD Rep Cooper FCSD Rep Cooper Conrad Cooper ;COtsifH0E1t~I IAL up zero, then youst i·11 win • d up wi·th .1_ 2- or 10, 10, 6 I in all your windows. I just don t t know how you re 10 ever going to do any better than that. (Unless you use the above procedure). Translation REP deployment was passable . This one you didn ' t . You didn ' t fire back at the REP after jettison? No. Let's replace this maneuver with the simulated opera­ tion (phantom rendezvous). We did deploy the REP and the radar did operate properly. Originally when the debriefing guide was made out, this section covered the translation back after REP deployment and the subsequent translations. Okay. We 'll just have to use the translations that they made on the simulated run. We kicked the REP out at 90 degrees right yaw. We kicked it out at 02 07 + 15, or 15 seconds l ate. The reason we were 15 seconds late , as we stated earlier, was that going into the night side the night before , after all our careful platform alinements, all of a sudden the horizon scanner began to drop out on us and we began to drift off in yaw. Conrad Dropping out wouldn't have been bad, but when it dropped out it also commanded some thrusting. Cooper We got some real good blips out of it. Conrad We were alining in the Horizon Scan Mode and I got the impression that it pitched us up. Cooper We wer e already alined, and we had gone to Orbital Rate and Horizon Scan, just to come alcng there in time to go in. As soon as we had the Ilatform all ali ned, and before we went in on the night side, I decided I would realine the pl atform ji.:st very briefly. So I had gone to SEF and to IULSE and I was checking and pulsing it . • But becai.:.se t hen in SEF position all your torquing is done f rom your Horizon Scanner. When the Horizon Scar,ner began to drop out we began to get real erratic needle display and it looked like our platform alinemEmt was deter­ iorating. I was trying to correct thiB, but obviously, it was really kicking us off. That was when we went t o CAGE , tried desperatelr to get it caged and realined in time , and thought we had i t realined. We may have had it reasonab:.y well alined by the time we f inally yawed right. I ·; looked like it was. The needles wer e all zeroed out and FCSD Rep Cooper Conrad Conrad Cooper Conrad everything was settled down. The Horizon Scanner .was working at that point. It quit working properly after we turned to yaw right . We had already gone into Orbital Rate, so we could care less about the scanner at this point . We got it alined, and we ' re already in Orbital Rate. We yawed right , got squared away and 15 seconds late ejected the REP on the IVI's all zeroed. We then used a couple of DIRECT pulses, zipped back around, picked it up going around to the 270. It was going right straight out to 270 on our ball . We could see the REP light whenever we were passing through the 90 degree point . On my side, I could see it flashing on the nose . By the time we got around it was in quite close, we could see it going out with a very slow tumble rate, flashing. What would you estimate the tumble rate to be? It was tumbling very slowly, I would say maybe a half to 1 degree per second. I 1d say a degree per second. I couldn't tell what it was in roll . It didn't seem to be tumbling in more than 2 axes. That was ha.rd to tell . When I saw it, you could see the dipole come around. We couldn 1t tell anything about roll, but it was not 38 tumbling in the other axes. The blanket was sitting _r ight next to it. Cooper The blanket went out and was sitting ri1sht by it. It went right on out with it . That was thi~ funny part of it. The blanket was between the REP and us. Conrad Yes. Cooper The blanket goes out first. The REP ha:3 a lot more mementum, apparently the REP had gone b;r the blanket: Apparently it had either hit it or moved it over or something because the blanket was betwe,m us and the REP. Conrad Yes. I don ' t know exactly what happenecl there. Cooper It was just a few feet outside of the REP. The REP went straight on out to 270, radar was working fine , r eading out everything just right , lock1~d on, and went out to the point where it should have s·~arted sl owing down. Conrad This is where I had a mistake in the fl:.ght plan and didn't catch it. The computer was in PHELAUNCH and I was wondering why I couldn't get any digital readout. I t took me a few seconds to catch on to that one and I realized that I had to get the computEir into CATCH-UP. We had never run into this problem where we'd gone through a complete insertion checklist 39 which calls for putting the computer to CATCH-UP. I had gone through and zeroed 25 , 26, and 27, talcing the ascent routine numbers out of it . So that I knew that we were getting the right readings. I had put the computer back in PRELAUNCH, also had this discus­ sion at that time and that ' s when I didn't blow the cold IR doors until the REP was out . Cooper I've said it before, and I also said it after my Mercury flight ; that is, "If you continually shove things in on people very early in the flight, the quality of it is going to be degraded." You need the first two or three orbits to check the systems over, to get oriented , learn how to aline the platform, to learn how to use the systems, to learn where things are, to do these things before you start giving -people complicated tasks . You just aren ' t going to get the quality out of them unless they're flying exactly the same vehicle for the second or third time and they 1re very experienced in it and they're familiar with everything that 's onboard and there ' s no change in equipment , no change in control system, no change in any of these things. Then, perhaps they could leap right off and go right into the first orbit and do these things. But to put somebody into iottf ~~ • 40 a strange vehicle, with strange control systems that you've only simulated as about best you can, and no visual simulation available for doing anything out­ the-window; you just cannot expect people to stay right on top of things when it occurs ir. the first part of the flight . This is an ideal eYample ; we had worked and worked and worked and worked and worked to have our timing down just rigl:.t. If noth­ ing had happened, we would have had our timing down just right and everything would have gor..e just per­ fect . Pete would have been right on hi~ checklist and blown the cold IR doors right on tirre. Cooper I I d have been right exactly on time on g·etting the REP out and everything would have gone reach- keen. Just that one thi ng, the Horizon Scanner failure , really threw the skids to the thing and caused us to be running sl ightl y late. There was added con­ fusion in trying to f igure out how to get t hings going and salvage the whole thing really threw the skids to it . Cooper The REP went out and it continued going out instead of slowing down as it should. It conti nued to move on out at quite a separation r ate. The thing that still has us a little puzzled, instead of slowing 41 down and coming to a null out there, it appeared to st art moving somewhat at the same separation rate to the south of us slightly towards a trail position very slowly. We tracked it f or a long t ime. We were track­ ing it straight out and then all nf a sudden, it be­ gan to loop around slightly to the lef t . Conrad It di d something like I 1 d never seen before! Cooper I 1d never seen this happen in the simulator, and it still doesn ' t seem quite f easi ble to us that this could ever happen. Conrad One possible answer, and it ' s r elated to something that we saw later in the flight , Gordo, where we alined the platform and had -yaw error couple into roll . Might not this have given us bad steering in­ formation as far as our radar needles were concerned if the scanner wasn ' t working properly? We didn ' t have the platform alined right . We went along 30 minutes, almost one- third of an orbit . If we di dn ' t have an alined platform, that would start coupling up in some other axis like roll and we woul d be off in yaw. Then when we thought we were pointing at the pole , we reall y weren't. Maybe it didn 1t reall y drift behind us , maybe it stayed out on our wing. We must have put it out fairly well 42 Cooper Conr ad Cooper Conrad FCSD Rep Conrad Cooper Conrad Cooper out of plane , in that it hung around us so darned long. It stayed with us for 20 orbits ! We saw it until the light burned out . I t was never f ar away from us. During five night cycles it was close enough that the flashing light illuminated the spacecraft . At the proper times, when we would get nodal crossing, when we turned around and actually saw the REP it was very close . We thought we were going t o hit i t . It was bright enough t o illuminate the spacecraft and the flashing light r eally impressed me . Did you take pictures? Yes , I think we have some 70- mm Hassel blad pictures and I took 16- mm moving pictur es. That was the last of the REP exercise . I understand all t he movie film came out, too. So you ' ll have pictures of it. At this point, we wer e rapidly running out of cryo­ genic fuel cell oxygen. We decided t hio.t the only way we were going t o salvage the f l i ght waE to stop using it at this rapid a rate . We had to make the choice whether we were going to power down and con­ t inue the f light, or whether we were gcing to end the flight very abruptly if i t continuEd going down [email protected]!9l!l'it~~. 43 at this rate. Cooper We had a short discussion on t his and decided that we ' d better power down and forget the REP because we were in trouble. Cooper So we tearful ly decided to give up the REP and power down. Houston agreed with us when we got in touch with them that we had done the right thing. That ended the REP. We did see it for quite a few orbits later. Then Houston came up with the simulated Agena ren­ dezvous exercise , which they put on one of their computers. The three burns they gave us to do went off very satisfactorily, the thrusters worked very well. They would not allow us to use anything but the aft firing thrusters because they wanted to keep the cryogenic oxygen in the right position in the cryo tanks. Apparently the burns went to their satisf ac-· tion too. They seemed to feel that it put us right where we should be. Cooper We tried one of these burns with the Platform Mode. It did not work satisfactorily so I used Rate Command Conrad which worked very well. 1 We t ried to take the errors out and thats where we got into trouble. We had about a fo error left and right and a fo error up and down , so Gordo fired off the fo tG~~FIDE► ,•♦♦ L. 44 FCSD rep Conrad FCSD rep Conrad left and r ight. We wound up witr. too much going forward and we started to back up and suddenly we remembered we couldn't back up so then we decided well , we 'd j ust leave thEi errors on the burn and burn i t the best we could because no matter what happened He're going to translate i nto forward and what we should have done and we didn't think of i t at the time--but you learn--we shouldn ' t have burned all the forward--we should have burned down to about a foot of what we were supposed to have forward ancl then taken out the left , right , up and down and go ahead and burn the forward again. The updates that they sent you on-­ That worked fine. There was no problem. We copied the numbers down, entered the computer. We had plenty of t i me to make the maneuver. We btuned r ight on the cl ock as advertised and we seemed to have gotten approximately i n the positi on they wanted us to get to. What burns did you si mulate? Well, we did a-- I 've got them right here. @oM~lA Al 45 Cooper Conr ad Cooper Conr ad Cooper Conrad Conrad FCSD r ep Conrad co~~r,ocr~r,At , We did a separation burn and we did a cl osing burn and a coelliptic burn. Those the ones we did, Pete? Well , i t was-­ We did not a standard coelliptic--it was a-­ No , we did a maneuver burn , which as--wait a minute--we did an apogee adjust maneuver which was a retrograde of 20.1 feet , then we did a phase adjust maneuver which was a forwar d burn of 15 feet . No . Yeah. 15.8 feet , then we did an out- of- plane burn, yawed left 900 of 15 feet and then we did a reverse coelliptic burn- ­ We burned- let's see--we burned 16. 4 feet forward and we di d four burns altogether. Aft thruster s for all? Aft thrusters for all- -on out-of-plane- ­ and that was the only t ime that we did ever, ever f ly the translat ional l eft , right , up, down thrusters. We used them to take out some of the IVI readings there Cooper Conrad FCSD rep Cooper Conrad Cooper Conrad Cooper Conrad Cooper a couple of times. And they were very straight forward--left, right , up, down. We even fired the forward-one quick l ittle blip. We fired the forward one then we suddenly remembered we weren't supposed to . What kind of visual out- the-window did you see on these translations? In other words-­ Left/right lights things up real w?ll- ­ I could see the glow from the aft--they were- ­ J. B. is referring to visual cues )n the horizon and we were on the gages-­ They were at night--middle of the night-­ everything we did was in the middl 1~ of the night--this spacecraft only ran in t he middle of the night (laughter) . I really don't remember making a burn-­ We never did anything in the day-­ Yeah, I think one or two of them were on the day side--but by and large-­ I never did so much night work in rzy- life-- EONFIDEt~ AL,. 47 FCSD rep Conrad Cooper 8 .3 RCS FCSD rep Cooper Conrad Cooper FCSD rep Cooper FCSD rep Conrad Cooper Cooper COt~FIDE~~TIAt OK- well, I don't think there is much we can add then--did you get all of these readings out of-­ 8O-81- 82- 58- 59- 69- Yeah, that stuff works just like the simulator. We got the readings . OK - On to 8.3 - RCS. Let's go into the RCS - yeah, I don ' t think there is anything more-­ This is all-­ Yeah, this is all we can do on the REP. OK- RCS Operational Checks - We did just like we had planned in our little book. We activated the RCS and Check Ring A and ACME and direct--al l three axis- Ring B - Check Ring Bin ACME and direct--all three axis and they worked beautifully. How about the pad checks--were they-­ Negative No pad checks? Not with the sealed system-­ A sealed system - I'm glad it was-­ Control Modes - We used pulse and we used horizon scan-­ tQEt◄Ttl<L 48 Conrad We didn ' t even check reentry rate command-­ Cooper We used direct, UBed pulse . We uned the rate command. We used hori zon scan. Conrad I know what it was--why don ' t you tell them about this--and I ' m going to see if I can get the fuel f i gures-­ Cooper OK. And they all worked very adequately. I thought the rate command system, I mean the RCS system was an excellent system. It was really crisp and just really, I thought, it was a real good solid system. Rate command was much more-­ FCSD rep What about the retrof ire - how did i t hold retrofire? Cooper Beautifully, it was just no effort at all­ ­ hold-­ FCSD rep + 1 degree or less? Cooper Oh, yeah, easily. We had a little offset in number 3 and number 4. I could feel them offsetting us. I just cranked in a little bit of RCS : Boy, it just glued it right in there, it just wasn ' t about -­ I felt like we could have had four or five times the offset we had--and never have ,. 49 GQt"EIDE~~TIAt FCSD rep Cooper budged it off there . RCS , I mean the rate command--One thing on rate command before retrofire and just after retrofire, waiting for retrojet , and then starting the pitch up to go up and roll over inverted and go to zero lift , the dual ring rate command is just mor e than you can handle. It ' s just a lot more than control authority than you want--you tend to over- shoot on things because there is just so much control tor que in there. As I had stated, after I f ired retro and jettisoned the retropack and pitched up to roll over then from ther eon I went to si ngle ring pulse, and used that. Reentry rate command--we didn ' t use . Direct - used direct t o do the reentry on single ring direct and used the pulse mode from r etrojet to 400K. On the single ring direct reentry did you have--did you feel like you had all the authority you wanted? Yeah--until very late--as I stated some time down, oh, half way thru the reentry ,_C~ Ji Hl:EttT 50 where you really begin to get the high g , after your high g , in fact, along about .. coincidental with a real high g, when you begin to get some fairly good oe1cillations , very r apid rate, I had no problE'ms damping them at all but I didn' t have tt.e time to keep switching back and forth f rom rate to attitude and go back to rate anc. damp them real quick and then go back to &.ttitude and decide where I was on the guide and then go back to rate and damp them and go back to guidance , so I finally--they got to getting fairly good where I had to devote a l i ttle bit of time to damping them, and I f i nally just went to guidance and stayed on guidance andJust flicked over tc single r ing rate command to damp the oscillati ons and then used the attitude control i n the rate command to steer the computer steers . Which worked out versJ well and there was--there never was really any oscillating-you never really--I could go to rate on there and you could hardly ever see the rate needles CQNftO Etsi:filA L -.. 51 COt-ct FID Et'<ITI AL jiggle--single ring was holding i t just as tight as could be. Retrofire attitude .. control - I had already mentioned on there­ dual ring. Rate Command, reentry attitude control-- I had already mentioned how we shot the reentry. No primary heater lights. Heater lights on the RCS - they were on practically--we had the heater on 99 percent of the whole flight. We turned it off, got heater lights on Ring A first, brought the RCS heaters on then rechecked-heater light went off and turned the heater off and about five or ten minutes later-fifteen minutes later, the heater light came on and then it was on Ring Band we turned the heater back on and this went on five or six times and finally we just turned the heater on and left it on the whole flight. I monitored the temper~tures f~equently throughout the whole flight in the RCS Ring A - temperature ran about 70 degrees or about 65 degrees and the RCS Ring B temperature ran about 70 to 72 degrees the entire flight . At <::.:.€0►~FIDE~~T IA L 52 FCSD rep Cooper one time I noted the RCS Ring B was up to 80 degrees. I watched i t quite closely for a while and then it never went beyond that and came on back down to about 70. And they stayed there essentia.lly the whole flight . I think you need thoee heaters on obviously the whole--all tt.e time--I'd never have any of them off at all now. Thruster firing colIDllents . When the RCS thrusters fire at night they clank out what­ ever you are l ooking at in the night side. The only way you a