NASA Press Briefings 7/17/97
Culbertson: ôOur original intent today was to brief you on the plans for the upcoming EVA, which, of course, we now expect would include Mike Foale, along with flight engineer Aleksandr Lazutkin. This was an EVA designed to recover some power from the Spektr module, which was damaged in the recent collision. However, overnight last night we received reports that, due to an inadvertent disconnect of a cable between the Omega attitude control system and the main computer in the Core module of the Mir, the Mir went into free drift and then the power, which, as you know, has limited margins right now, was reduced to the point where they had to shut down the gyrodynes, go into jet control, and then eventually had to go back to controlling with the Soyuz module as they did about three weeks ago when a similar event happened. So this is pretty much a replay of what we saw at that time when they got very low on power, had to methodically bring the station back into the proper attitude for maximizing sunlight on the arrays, building the charge in the batteries, regaining their margins, spinning the gyrodynes back up, and getting back on nominal gyrodyne control. This whole process takes about two to three days. We expect that to be true in this case, and in the meantime the crew is still safe and in good condition, but operating in the dark to a large extent because they are minimizing the load on the batteries and the solar arrays. They have also shut down the Elektron and the Vozdukh systems. The Elektron actually was not being run very much at this time because the Progress had just come aboard with additional oxygen for the crew so the partial pressure of oxygen was very comfortable. CO2 is being removed from the atmosphere by the lithium hydroxide canisters that are onboard for that purpose, and they run a fan to route the air through the can and that keeps the partial pressure of CO2 well within our normal limits. Temperatures are running pretty close to normal right now and IÆm sure that thermal control will be one of the first things they regain as they bring the power back up and start putting the systems back on line.
ôThe Russian flight Control Center doesnÆt have a lot of information right now on the exact state of the Mir because they donÆt have telemetry at this time. When they start getting coverage by Russian ground stations in about half an hour, theyÆll start gathering more data and be able to help the crew a little bit more specifically on attitude as well as load balancing between the solar arrays and the batteries. In the meantime theyÆve been talking to them through U.S. ground stations. WeÆve been using Dryden, White Sands, and Wallops stations as we have in the past, and those folks have been very responsive and weÆve gotten very good communications by that means and the Russians have been very appreciative of that.
ôAs far as the plans for the EVA, I had intended to go over that in some detail and IÆll continue to do that; however, we are not sure what the schedule will be at this time. Because of the problem last night, ,the crew was given some time to work this problem and some rest today because they were up much of the night, and theyÆll probably be given rest tomorrow, so this puts them a day or two behind on the training plan and to prepare for this EVA, which was scheduled for the 24th of July, so I suspect it will not be conducted on that date, and in a day or two the Russians will make a decision on how much it will be delyaed. I suspect the final decision wonÆt come until all the power is recovered and the gyrodynes are back in control and they have a chance to assess the overall situation and what time remains prior to the next Soyuz launch, which right now is scheduled for August 5th. The EVA itself was planned to be done internally to the transfer node with the replacement of the hatch on the Spektr module with the modified hatch. Originally they had planned on using the commander, Vasily Tsibliev, and the flight engineer, Aleksandr Lazutkin, to conduct this EVA, with Mike Foale located in the Soyuz module during this time communicating with the crew by radio and being there in case a contingency arose and they all needed to evacuate the station.
ôSubsequently to that original plan during normal medical tests in preparing for this EVA, they discovered an irregular heartbeat on the commander and decided it would be wiser to not have him do this EVA and asked us if we would mind if Mike Foale conducted it. Mike, of course, has been trained as an EVA crewmember on both the Shuttle and the Mir. He was Jerry LinengerÆs back-up for his mission and could have conducted the EVA on that mission if called upon. He has received a good deal of training in Star City. They have reviewed his training records and he performed very well there. He also conducted an EVA on the Shuttle in 1995, so heÆs a well-experienced crewmember and really just needs some review. And if you think about it, training on orbit in a suit is even better than training in the water tank because you are weightless, youÆve got the actual equipment, and it would be the best training session you could ask for in preparing for it. ThatÆs one of the things about a station, you do have that luxury of going through a full dress rehearsal before you actually conduct an EVA of this sort. We donÆt have that luxury on the Shuttle because we generally have shorter missions and less resources to do that.
ôAt any rate, we have thoroughly evaluated that. We took some time to make sure that we addressed all the concerns for both the training itself and the conduct of the EVA. Right now we have given a go to the Russians for Mike beginning the training, which consists of a rehearsal without the suits--going through the motions, using the equipment, and going to the places where they need to operate in the node, simulating the hatch maneuvers, etc.--and also a fully suited rehearsal with the suits closed and pressurized, but with the node still pressurized and not evacuated as it would be during the EVA. The final decision on the EVA for all crewmembers will be made at a joint readiness review that we will conduct together with the Russians by video about two days before the EVA would be executed. That would be after all the rehearsals and we have all the data on hazard analysis and any other concerns people might have about our readiness to do that. We have not given them a go for conducting the EVA, but, of course, they havenÆt given their own crew the go for that, but we have given the go for preparations and training.
ôTo go into a little bit of detail on how the EVA will be conducted, the diagram shows the Spektr module on the right, the transfer node right in the center (yellow), which is where the actual equivalent of an airlock will be located for the crew. They will go into the transfer node fully suited, close all the hatches that surround it, and then evacuate that transfer node just as they would an airlock, and then they can open the hatch to the Spektr module and both will be at the same pressure, near zero. The Soyuz module would have the commander aboard in the descent portion, which is the center part, and the crew could have access--though the hatch would be closed it would not be latched-they would have access to the habitation module, which, if necessary, they could use as a subsequent airlock if they had trouble repressurizing the node. The Base Block is off to the left and there is a Progress docked here at this time, which has now been emptied and is ready to undock also if necessary if they need to clear that docking port. So, essentially, they would come from the Base Block after suiting up into the transfer node, close all the hatches, evacuate the node, and then begin the EVA.
ôThis is an interior view of the transfer node itself. The hatch that they are modifying is the one that Valeri Korzun is actually holding in his hand there. The bottom portion of it will have been removed and replaced by the hermetic plate, as they call it, that contains the connectors that will be used for transferring power from the Spektr to the Base Block itself, and that will be all modified and finished in a shirt-sleeved environment and will be ready for installation once they go EVA.
ôThe Spektr hatch itself is in the center of the picture. This picture was taken during normal operations when they did have cables running through the hatch, and the larger cables are the ones that were disconnected and moved out of the way when they closed the hatch to isolate the leak that occurred during the collision. ThatÆs John Blaha inside the Spektr module to give you a little bit of scale and the internal hatch on the Spektr is the dome-shaped object. This is open right now and tied back with a bungy. There are some cables that are behind that hatch that theyÆll need to gain access to if they want to fully connect all the solar arrays. And probably the most difficult part of it is reach the cables back there. The hatch that is sealing it is actually a plate that can be removed totally, and seals against the surface that can be seen in the foreground. ItÆs a plain hatch at this point, and itÆll be replaced with the modified hatch during the EVA.
ôHereÆs a little bit closer view looking through the hatch of the Spektr. You can see again this internal Spektr hatch out of the way and the cables that come through, and then you can see also how the Spektr kind of necks down as you get further into it, so they really donÆt intend to go very far into the Spektr itself. In fact, the primary intent is to go just barely inside the hatch if possible, locate the cables, connect them, and then when they finish that, theyÆll probably do some looking around, both during daylight and during night to see if they see any evidence of where the leak might be in the bulkhead. But theyÆre not very confident theyÆre going to be able to locate anything without going pretty far into the module. This crew would not do that. The next crew coming up is conducting some training now to see if they can go very far in to do a more thorough search and maybe a repair in the future.
ôThis is a view looking from inside the Spektr back into the transfer node, which is in the shadow. On the left is the hatch I mentioned earlier and you can see how some of the cables run behind it and back in underneath, and the cables that they have to get to are located on plates such as you see in the picture that theyÆll have to gain access to and then connect to the hatch itself. The modified hatch is basically the dome-shaped hatch in the earlier picture with the modified connector plate attached to it, but also with jumpers coming off the plate that will make it easier for them to connect the internal connectors and cables, so they wonÆt have to reach down inside the plate itself.
ôThis picture gives an idea of what itÆll look like as they perform the EVA. This is a shot taken from the Hydrolab in Star City where they conduct their EVA training underwater. You can see here one of the cosmonauts entering a representative hatch that is just about the same size as the Spektr and you can see the clearance is somewhat limited although he can get through there.
ôIn this picture you can see he has entered and is able to enter with clearance. The suits theyÆre using will be attached to the transfer node with umbilicals so Mike FoaleÆs primary job will be to watch Aleksandr Lazutkin who will be in this position during most of the EVA and Mike will help tend his umbilical, watch for clearance for him, and help clear snags if necessary, and of course monitor the systems associated with the EVA in the transfer node and help operate the depressurization and repressurization controls. So Mike will be basically a back-up to him and Lazutkin will be the prime for going in and working with the connectors and doing the actual work inside the Spektr module. Their initial estimate is that the picture here is about as far as heÆll have to go to get the job done. If he canÆt quite get to some of the connectors, he may have to reverse direction and go in feet first and in that case he would be further in, but theyÆre hoping he doesnÆt have to do that, and of course, in that case, he would have eye contact with Mike and they could communicate over what needed to be done even if the radios were to fail.
ôSo thatÆs a brief run through of the physical layout of what theyÆll be doing. WeÆll have better pictures after we do the joint review and reach a decision on whether to go with it or not and weÆll try to give a more thorough explanation of the route they will take, etc. Basically during this time the two crew members will be in the evacuated node, the commander will be in the Soyuz in radio communication with them and standing by until they finish, and then they can reopen the hatches and hopefully regain some power and increase the margins. If they had had that power last night during this problem, we may not have been in the same position of having to power down the gyrodynes and go through the whole process once again of power up.
ôI probably havenÆt covered everything, so IÆll be happy to answer any questions you might have and let you know where we think we are and where weÆre going.ö
Q: ôWould you discuss the risk-benefit of this spacewalk with Mike Foale? Is this really worth doing, and what do you think youÆll gain in terms of electrical power?ö
Culbertson: ôPotentially they could regain about 300 Amps of power. It could be as high as 2 to 2.5 kilowatts of power, which will put them back in a pretty good condition. Right now theyÆre generating about 4 to 4.5 kilowatts on average, I believe. But they do need the power margin in order to be able to have some flexibility to get out of attitude if they need to do a docking or, if they were to have some other problem with the attitude control system, theyÆd need some margin in the batteries. They can, at this point, if they regain that power, repower the Krystall module and also the Priroda, which is where the remainder of our experiments are located. Krystall contains the attitude control computer that theyÆre using right now, as well as some other equipment that they would like to have powered up and also there are batteries in those modules that could be repowered if they were to regain the solar arrays. So there is some risk, but the risk, we believe, is minimal, as far as an EVA goes. In fact, if you think about it, doing an EVA inside takes away one of the risks, which is becoming untethered, and you donÆt really worry about that. They are following a procedure that they have followed several times in the past. ItÆs an already published flight data file for them. The only change to it is the actual connection of the cables because they used this EVA to reconfigure and move around hatches whenever a new module comes up and theyÆve had to move them from one place to the other. So itÆs been done several times in the past. ö
Q: ôCould you discuss what the Mir crew was doing when the cable became disconnected?ö
Culbertson: ôAs I understand it, they were looking at the connections and disconnections they were going to have to make during the upcoming EVA and probably looking at the location of the cables and maybe practicing, seeing how much torque it took to disconnect or reconnect them, and it appears that they inadvertently disconnected the wrong cable. It happened when they were not talking to the ground, I believe, so I donÆt know the details of exactly who did it or what they were attempting to do at the time, but I know leading up to that they were having some discussions about what they would do with the cables during the preparation for the EVA itself, because they will have to disconnect cables between all the modules.ö
Q: ôHow did disconnecting one cable throw the Mir into such turmoil?ö
Culbertson: ôItÆs a good question and one that weÆre looking at very closely too. I believe what happened, based on what I know, is that when this one cable was disconnected the computer got a signal it had not seen before and not been programmed for so it just basically shut down all operation, all control of the attitude. Normally they would go to a back-up system, but because this was an unexpected type of failure, I believe it did not immediately kick in. It takes some time for the gyros and the back-up Ort computer, as we saw a few weeks ago, to come up to speed and regain attitude control. By the time it did take over attitude control, it appears that it had about a 45░ error in its inertial reference plane and so they were not in an optimal pointing attitude for the solar arrays at that time. Without data to the ground, the ground has minimal ability to tell them exactly what attitude to go to optimize the pointing of the arrays. There are a lot of them and if theyÆre not pointed very well, they can shadow each other and you can end up with one shadowing another and reducing the power. So itÆs critical that it be pointed in the right direction. When that attitude was off, they went to further back-up, which is a magnetic sensing reference, but that takes a couple of orbits to stabilize and my understanding is that when that had stabilized and began to give them some good information, the power had dropped to the point in the batteries that they could no longer keep the gyrodynes on line and eventually they had to shut off the main computer and a lot of the other life-support equipment. So they had to go to the Soyuz at that point, using it again to begin pointing manually and start regaining power, but keep the load really down.ö
Q: ôWhat role does crew fatigue play in this?ö
Culbertson: ôWe donÆt know for sure. It could be a factor. ThatÆs something that I know that the Russians are looking at very carefully and weÆre evaluating ourselves. We look at this all the time in spaceflight. You want to make sure the crew is ready to do what theyÆre asked to do.ö
Q: ôAre you concerned that if you donÆt do this cable repair the lack of power will jeopardize docking in August?ö
Culbertson: ôI believe that they can safely conduct the docking in August with the current power levels, but it takes away some of their margin if they had to delay for an orbit or, if the Sun angle were such at that point in the year that they had minimal coverage of the arrays, it would give them less time when they could stay in an optimum attitude. So it takes away some of your flexibility in a situation like that. Or if you had to back out and try it again or something like that, it would reduce those options. Back to your previous question, as far as crew fatigue specifically playing into this one, IÆm not aware of an overly strenuous day for the crew leading up to this. They had had a fairly nominal schedule and had been doing some review of the timeline for the EVA and had not been involved in some of the past heavy maintenance activities that they have been conducting, so maybe in an overall sense itÆs been a tough mission for them and that may have played into it, but that particular day I donÆt believe was very stressful.ö
Q: ôWhy not wait for a fresh Russian crew who has rehearsed this on the ground? IÆm not sure I understand the urgency of dealing with this issue with this crew thatÆs had so many difficulties.ö
Culbertson: ôThatÆs certainly an option, and one that has been open all along and one that weÆve been looking at. WeÆve had some discussions with the Russians about that, specifically when they requested that Mike do this. IÆve been told that they would like to regain the power as soon as possible just because of this margin issue of having enough flexibility to deal with problems or to give yourself some other options. But also they were hoping that if there were a problem with this EVA or something else cropped up they might be able to identify it before the next crew came up and bring up additional equipment if that was what was needed to solve the problem. So it just keeps some of their options open on both power generation as well as logistics to support subsequent EVAs.ö
Q: ôDid you or any other top NASA officials have talked directly to Mike Foale about substituting for Tsibliev for the spacewalk and what did he say? Do you think he might be feeling pressured into saying yes whether he wants to or not, and whatÆs his wife been saying about this and is she being kept abreast?ö
Culbertson: ôShe is being kept very well informed of it and as far as I can tell sheÆs very comfortable with the idea. Mike has done an EVA before and sheÆs very confident in his abilities, as are we. I talked to Mike almost immediately after the proposal was raised to us and I guess æenthusiasticÆ would be a good description of how Mike felt. He had told me before the flight that he sort of wished he were scheduled for an EVA. Almost every astronaut enjoys doing that because it is a challenge and itÆs a great view and also a demonstration of doing in space what weÆre there to do, which is human activity in the vacuum. So Mike didnÆt have any problem with this. He did want some time to review the procedures and understand what he would be required to do and the Russians were certainly willing to grant more than sufficient time for that, so he felt very comfortable with the plan. He also felt like Tsibliev would be an excellent instructor for him. He has a lot of confidence in his ability both as an EVA crewmember and as a teacher of what needs to be done, and he felt that between the two of them he could become very well prepared for it.ö
Q: ôGiven todayÆs problems, how does NASA in good conscience even think about sending Wendy Lawrence or any other American to Mir at this point? Certainly this puts a whole new slant on things.ö
Culbertson: ôI donÆt believe this particular event changes the way weÆre looking at things at all. This is an event that theyÆve dealt with before. We are concerned about it, of course, but we have not actually begun the review process for WendyÆs readiness for flight, nor the advisability of beginning that mission. We will do that starting in August and the final decision would not be made until probably the first week in September at the flight readiness reviews for STS-86.ö
Q: ôPresident Clinton said today that he didnÆt have enough information or hadnÆt been given enough information about Wendy LawrenceÆs mission, further Americans going to Mir. What additional information does NASA need? Are you still collecting information on this, and when can you make some decision about whether she should go or whether any American should go to Mir?ö
Culbertson: ôI think it would be irresponsible to make a decision now on something that needs to be done two months from now. We could say ægoÆ now and things could get worse or we could say ædonÆtÆ go now and things could improve. I think we need to see how things are as we get close to the scheduled time for that mission, our readiness for it and the ability of the Mir to support our program and people safely, and we will do that in time. It would be premature to make a decision now and thatÆs basically what Mr. Clinton said.ö
Q: ôCan Mir in its current state handle six cosmonauts, astronauts? In other words, when the crew gets up there August 5th, if you didnÆt do this EVA, if you didnÆt restore that power, can the life-support systems support that many people?ö
Culbertson: ôIÆm skeptical that it could at this point. The Russians have said that they think they could, but they are not willing to make that decision until after the EVA to see how much power they do regain. I believe this is something we need to look at very carefully and discuss with them just how much time you could afford to have six people up there and whether itÆs the right thing to do at this point or not.ö
Q: ôIt appeared that they accidentally unplugged the wrong cable. There were some conflicting reports this morning that perhaps they were following instructions from the ground that were in error. Do you have any clarification of that or do you think itÆs just they onboard the ship made the mistake?ö
Culbertson: ôI really donÆt know. Either scenario could be accurate and we donÆt have much insight into that yet. I havenÆt seen the actual instructions that they were following, if any. They may have been doing this on their own, but weÆre still trying to figure that out.ö
Q: ôCan you describe some of the scenarios that you are looking, realizing that these are moving targets and nothingÆs written in stone, but looking ahead, the Russians are testing sealants. They think they can perhaps down the road repressurize Spektr. Could you discuss what some of those long-range plans are and what might be done on STS-86 in terms of the EVA that already planned? Is there any way to get Titov and Parazinsky up on Spektr to look around? Is that an option?ö
Culbertson: ôWe have been looking at a lot of those options and a lot of our people that arenÆt involved in the day-to-day operations are busy looking down the road at what can be done. The Russians have asked us for our own ideas and if we know of any materials that can be used in this way, and we have provided them what information we have. TheyÆre looking at several different ways they might repair a potential leak, but the problem is they donÆt know exactly what it looks like or where itÆs located. So until we know the exact character and location of the hole, itÆs difficult to build a specific repair procedure. So I believe that looking at the area, if theyÆre going to do a repair, is critical. We are looking to see if thereÆs anything we can do during STS-86 in terms of a fly-around, photographic survey, or other sensors to see if we can help them locate it. We have talked about the possibility of modifying the EVA during STS-86, but right now, because of the short amount of time available and the limited training facilities available, itÆs doubtful we would do very much beyond just look across from one spacecraft to the other and see what can be seen. If we come up with a way that they could do an on-site inspection, weÆll look at it very closely, but right now that looks pretty difficult given the configuration of the Mir and the training time available.ö
Q: ôSome space analysts are saying that itÆs a conflict of interest for you to be deciding such matters when youÆve been promised, at least unofficially, the last Shuttle-Mir flight. How do you respond to these kind of concerns?ö
Culbertson: ôI donÆt really think about that. I havenÆt been assigned to any mission and my main concern is the safety of the crew on orbit and the safe conduct of the program. Any future missions is not an issue whatsoever with me. If there are missions to Mir available and IÆm relieved from this job, IÆd be happy to take it if I were assigned, but thereÆll be other missions beyond that, and as long as I can stay healthy and stay on flight status IÆll be available for them if theyÆd like me to go do them. But STS-91 is not an issue to me. Right now IÆm concerned about the current mission.ö
Q: ôHow much more in the way of problems are you and others at NASA, at the decision-making level, willing to tolerate on Mir before standing up and saying, æWell, enoughÆs enough. It's time to stop sending Americans to Mir. Æ In addition, how can this possibly be good use of the taxpayersÆ money at this point?ö
Culbertson: ôAs far as our review process for the current mission and the future missions, we do have a process that weÆre going through and we are looking at and maintaining awareness of what the situation on the Mir is in terms of consumables, life-support systems, repair capability, and, of course, just the living conditions and safety of the crew, and we do that on an ongoing basis and we do it specifically for the missions that are coming up in a very detailed fashion, and weÆll continue to do that. If future problems arise then they will be factored in and dealt with accordingly, just like we do on any spaceflight whether itÆs to a Russian spacecraft or on an American spacecraft. And as far as this being a good use of the taxpayersÆ money, thereÆs no doubt in my mind this is a good use of taxpayersÆ money. It weÆre going to be a spacefaring nation and continue to operate in space, itÆs important that we learn everything we can about what it takes to operate in space and these are very graphic lessons of what it takes and some of the risks are being highlighted for us, but I think that we will be able to operate safer in the future because of it and as long as we can maintain our minimum safety margins and be aware of whatÆs happening up there, I think that weÆre getting extremely valuable benefit from being in space. But thereÆs no doubt that this is a situation that we need to watch very carefully and thatÆs what weÆ're doing. So itÆs good training for the managers and flight controllers and everybody else on the ground too.ö
Q: ôDo we understand, then, that you feel that itÆs important enough to gain this experience and therefore youÆre trying to sending Americans up there. ThereÆs no cut-off point where you say ÆWell, now thatÆs too much for us to take and put Americans at riskÆ?ö
Culbertson: ôThere would be a cut-off point that thereÆs too much, but I canÆt identify that right now.ö
Q: ôWhat was the extent of power loss that resulted from this disconnected cable? Some have called it a complete loss of power and I was wondering if that was accurate.ö
Culbertson: ôThe disconnection of the cable did not cause any power to be lost. It was a data problem that caused the computer to drop off line and cease its normal function of controlling the Mir and its solar arrays. The power loss came gradually over time as the batteries drained and didnÆt have sufficient recharge from the solar arrays because they werenÆt pointed in the right direction.ö
Q: ôWere the batteries completely drained?ö
Culbertson: ôNo, not all the batteries were completely drained, but the ones in the core module got below their minimum for staying on line and the automatic systems, at a certain point, when they get below a certain voltage, do cause them to drop off and thatÆs what they reached. ö
Q: ôAt what point did the crew actually get into the Soyuz? Did all three of them get into the Soyuz and if so, how long were they in there, and are they back out working in the dark? Essentially are you back to square one from right after the crash?ö
Culbertson: ôTheyÆre pretty close to that situation right now, thatÆs right. They have powered off a lot of the lights and other equipment just to reduce the load on the electrical generation system. They probably are using flashlights. They did not all get into the Soyuz I donÆt believe. They got into the Soyuz when they needed to talk to the ground, so it probably only took one or two to do that, and then of course the commander go into the Soyuz to maneuver the whole stack to get it pointed back toward the Sun. I believe there was some misinformation floating around. They did not evacuate the station or get into the Soyuz in mass. They had to get into there just to conduct some of the operations. And theyÆve been alternating between Soyuz communication and Base Block communication since that time.ö
Q: ôWhat is the propellant situation on the Soyuz? How much was used in this maneuver? Are they close to the red line that they might need if they had to make an emergency evacuation?ö
Culbertson: ôI was told this morning that they have about 495 kilograms of fuel onboard the Soyuz. They need about 200 kilograms for a deorbit, so theyÆve got plenty onboard. They were saving some for a possible flyaround of the Soyuz from one end to the other just because they preserve that option throughout the mission if possible. They have canceled any plans to do that, so that opened up another 200 kilograms, so they have lots of margin for conducting maneuvers with the Soyuz and I donÆt believe that should be a limiting factor here at all. They only use about 15 to 20 kilograms per maneuver.ö
Q: ôDo you know yet or have further information on what caused the collision with the Progress? Was the capsule overloaded?ö
Culbertson: ôWe donÆt have any more information on that yet and we donÆt expect a final report until after the crew lands and they are a part of the interview process and part of the investigation.ö
Q: ôDo you derive any sort of encouragement in sort of a backhanded way from the fact that what happened overnight was human error rather than yet another thing breaking? Is that something that allows you to say æLetÆs keep going with this, Æ and not to get as discouraged as you otherwise might?ö
Culbertson: ôI think itÆs important to keep all of it in perspective. Human error is one thing and systems problems are another and you just deal with them as they occur and try to keep it all balanced and make sure that you understand the whole picture, so I wouldnÆt isolate one from the other. I think we need to continue to look at the Mir as a system, including all of its ground controllers and crew that happens to be onboard at the time.ö
Q: ôIf there is any setbacks in the attempt to restore Mir to how it was before the cable disconnect triggered all the related problems, how long could they stay in their current configuration and what would be the limiting consumable that would force things to deteriorate rather than regain ground?ö
Culbertson: ôIf they had no way of regaining power whatsoever, then they would be in pretty sad shape, but right now the powerÆs continuing to slowly build up in the accumulators and in the batteries and itÆs just a matter of time to get up to the point where they can restart the gyrodynes and bring the life-support systems back on line. If youÆre talking about many, many days in this situation, the limiting factor would probably be lithium hydroxide for CO2 removal, but theyÆve got 25 daysÆ worth of that onboard and I donÆt believe itÆll take anywhere near that. In fact the SoyuzÆll be there before that, to regain attitude control.ö
Q: ôWhen does the station itself need to take over attitude control? When can Soyuz no longer be safely used to control positioning?ö
Culbertson: ôThe Soyuz has almost 300 kilograms of fuel available for positioning and I believe it can used as long as that fuel is available, if necessary. TheyÆre not continuously firing the Soyuz jets. What theyÆve done, basically, is set up a rotation rate with the Soyuz so that they can tend to point toward the Sun in inertial attitude as they go around the Earth, which takes some rotation in relation to the Earth, of course, and they tweak that every once in a while as they come into sunrise to try to optimize the pointing as well as the rotation rate. But it doesnÆt need to be done very often once they set it up if itÆs done skillfully.ö
Q: ôBecause they lost power so quickly, is it really that theyÆre hanging on a thread as far as powerÆs concerned, that the batteries are just topping themselves up during the daylight pass and really only have enough just to make it through the night portion of the orbit?ö
Culbertson: ôNo, actually, I think this took about five orbits. And I believe it was partly due to the fact that they happened to be in a regime where they were not getting telemetry to the ground, they were relying only on voice through our ground stations between the Mir crew and the SOUP and I believe that the backup systems were just a little slow coming on line and in hindsight maybe they could have been a little more aggressive about some things. ThatÆll come out as we have further discussions. Or maybe it was just an artifact of the fact that it happened during the crewÆs sleep period and they just needed to get things going. It just deteriorated over time, but it did take several orbits for that to happen.ö
Q: ôThere have been several reports out of Moscow that tension is running quite high in the Mission Control Center that some people may have been snapping at each other there. Have you been able to gauge how everyone has dealt with this and whether thereÆs a sense of frustration that it seems youÆve taken one step forward and two steps back?ö
Culbertson: ôNobodyÆs snapped at me, but I can imagine that they are nervous over there and probably frustrated because theyÆve been working very hard to bring the Mir up a fairly high standard. In fact, if you think back to before the collision, the Mir was as capable, in fact more capable, than it had ever been on orbit in terms of redundancy power generation capability and productivity in the research area. They had worked very hard to overcome their systems difficulties and had a great plan in place to increase their redundancy. So, yes, this has been very frustrating to the folks who have worked to reach this point and one more problem on top of that, which you probably wouldnÆt have even noticed if we didnÆt have all these other problems here, just probably adds to their frustration. I donÆt blame them at all. These are human beings.ö
Q: ôHave you managed to complete your studies into the possible indeterminants that might be lurking behind the door of Spektr and also what kind of evaluations youÆve done, whether youÆve put some of these objects, such as the fixative containers, in a vacuum chamber and seen what kind of results you get when you evacuate the chamber?ö
Culbertson: ôAs a matter of fact, we have. We are not quite through with all the analysis, but so far we havenÆt identified anything that would be a specific hazard to the crew. We have put some things in vacuum chambers such as batteries and the fixatives and have not discovered any problems with any of them. We donÆt anticipate that there would hazardous materials or things floating in the Spektr that would be a problem for the crew. However, we have also suggested, and the Russians have their own plans, which we will integrate with them, ways in which to mitigate any hazards that might show up such as having clean-up materials, towels, plastic bags, etc. available, should something appear when they open the hatch so that they can gather it up or clean it up. I suspect that most things have found a resting place in the ensuing time and as long as the Mir is relatively quiescent prior to the EVA I donÆt expect a lot of debris or other matter floating around in the way of the cosmonauts.ö
Q: ôWhat kind of concerns do you have, both for Mike Foale and for Sasha Lazutkin, given the fact that MikeÆs training as JerryÆs back-up was primarily for an external EVA to install OPM, whereas Sasha Lazutkin has never done an EVA previously?ö
Culbertson: ôSashaÆs very well trained on the ground also, and Mike has experience in EVA and in the Russian and American suits. The number one concern during an EVA, I believe, is the crewmanÆs ability to deal with his suit and maintain his own vitality, his own life-support systems and deal with any contingencies that come up. The location of it is another factor that you work with as you conduct the EVA, whether itÆs inside or outside, whether youÆre worrying about snags or sharp edges or the route you have to take or whatever. You deal with that during the preparation and the rehearsal. But the number one concern is that the crewmember knows how to use the suit, how to deal with emergencies if they should occur, and I am confident Mike knows how to use the suit and will get refresher training that will be very valuable and he will be fully up to speed before he actually conducts the EVA. Sasha was planning on doing two EVAs during this mission anyway, so he was fully certified and prepared, so I donÆt believe there are any issues in that area.ö
Q: ôIf SashaÆs suit was to get cut from something while heÆs in Spektr, how quickly could he get out of that situation back into the node, close the hatch, and get repressurized? Would it be a very rushed situation? Would he have some leeway time before the suit would leak too much, and what would have to be done in that kind of a scenario? For instance, I understand at the elbows the suit is only a single thickness.ö
Culbertson: ôThey have a back-up air supply just like our suits and if they encountered a leak they would open that back-up air supply and of course feed the leak to try to maintain pressure. On a nominal repressurization, once they close the hatch, which I believe can be done fairly quickly, itÆs about a 20 or 30 minute repressurization, and generally you have about 30 minutes on the back-up air supply. But it can be done quicker than that. I donÆt know the exact numbers, but according to people like Sergei Krikolev, who have done many EVAs, it can be done fairly rapidly. So they believe that any leak size that is reasonable or expected in a case like that they could deal with.ö
Q: ôGiven this latest power outage, whatÆs the status of the rest of the experiments, especially the U.S. experiments, the greenhouse, the beetles? Are any of them at risk now due to the lack of power?ö
Culbertson: ôThey were operating at a fairly low power level already. The greenhouse can go a couple of days without watering or light. The beetles can actually go about 25 more days on battery power if necessary, so itÆs just a matter of whether he can actually get to them and tend them, provide water and light for the greenhouse experiment. Right now I believe theyÆre pretty much status quo and weÆll watch over the next few days what heÆs able to do to recover them.ö
Q: ôYou said that this repair mission was a minimal risk. Have you made a formal probability of success estimate on this mission?ö
Culbertson: ôNo, we havenÆt done a statistical analysis on it. When I say minimal risk I mean in terms of the normal risk that you encounter during an EVA. ItÆs not a risk-free environment. ItÆs just that you do everything that you can to manage those risks and we have the spacesuits on both sides, as well as procedures that are designed to minimize those risks and deal with them, control the hazards that you might encounter. Being in space itself is not a risk-free environment, but speaking in terms to an EVA where you might encounter the need to do extremely complicated repair or move large objects around, this one is fairly minimal in relation to that.ö
Q: ôSo this is minimal risk relative to EVAs, but itÆs a risk, thereÆs some risk.ö Culbertson: ôCertainly thereÆs a risk.ö Q: ôSo youÆre saying itÆs unlikely anything would go wrong. If there were any mishap, people might ask why are we doing this mission. Could you, in very simple terms, explain why itÆs in AmericaÆs interest to do this EVA.ö
Culbertson: ôWell, I believe that the primary reason for going ahead with the EVA is to regain some power for the station itself, which will make life better for Mike Foale onboard, who is our American up there. Of course itÆll benefit his other crewmembers, which weÆre also concerned about, but I believe the more margin they can have in power the better off theyÆll be. TheyÆre OK right now, once they regain attitude control, but weÆd like to see more flexibility. The secondary reason is for going ahead and conducting it are the same reasons that we had for having Jerry Linenger do an EVA during his mission, which was the one just previous to this, and thatÆs the learning of the Russian procedures and what itÆs like to do an EVA in a closed environment. ThereÆs always a chance during the upcoming International Space Station that we might have to repair a depressurized module or go in to retrieve equipment or whatever. WeÆve done simulations of that in the water, but this is the best simulation you can get, and I believe that weÆll learn some good lessons from this.ö
Q: ôAre there any unkowns in this EVA that youÆre trying to get a better handle on, issues that are poorly understood at this point, such as disconnecting all the cables and all the hatches?ö
Culbertson: ôThere are really no unknowns, there are no hazards that we feel we donÆt have a basic understanding of. We have not identified anything that we would consider a showstopper at this point. There are some things that weÆd like to be more thoroughly addressed, such as how we deal with communication failures or umbilical failures, but those will come in time and they will be thoroughly answered at the readiness review couple of days prior to the EVA itself. Basically, itÆs a well-understood activity by both us and the Russians. TheyÆve been very open about our people participating in the preparation and planning for this and our people are very confident that everyone knows what weÆre doing here.ö
Q: ôYouÆve all been working very hard I understand, but nevertheless there seem to have been some communications confusions to say the least between what he Russians tell us and what the Americans, you and Houston, tell us about the situation. Are you at all concerned about the lag time between the time you get full information about things such as the emergency last night? And could you react fast enough in an emergency given this lag time? And could you include in your answer some details about the mechanics of how you do get this information?ö
Culbertson: ôGenerally in a situation like this my phone begins ringing in the middle of the night and rings for the rest of the night and thatÆs what happened last night. As soon as people understood what the problem was, we were notified and our folks began participating in the process. The fact that we are dealing with a nine-time-zone difference here is a factor in the lags and, in general, I feel that because we have people on site and because the Russians know who to call and we know each other very well, that weÆre actually communicating very well. If thereÆs a lag, itÆs mainly due to the logistics of the situation and not due to any reluctance or inability to communicate. In general I feel that weÆre communicating extremely well in this situation, far better than we were at the beginning of the program.ö
Q: ôWhat will Mike Foale have to do in terms of gestures and movement? Some EVA veterans have raised a concern about the fit of this spacesuit, which was not designed for him. Is the fact that the gloves were not designed for his hands, for instance, a problem?ö
Culbertson: ôIt could be. That will be verified during the fit check, which was scheduled to occur in a couple of days, and that will all be a part of the readiness review process as to whether he can use the suit thatÆs up there, whether it fits well enough. If it doesnÆt fit well enough and heÆs not happy with it, we wonÆt do it.ö
Q: ôDuring the EVA, will you leave all the decisions on whatÆs going on to the NASA people and the Russians in Moscow, or are the NASA people in the U.S. going to be online ready to make some calls in case thereÆs some problem? WhoÆs going to be ultimately in charge during that EVA from our end?ö
Culbertson: ôThe way that would work would be like any operational situation, the same way we do with the Shuttle. When youÆve got a real-time operation going on, the flight director and the crew commander are together in charge of whatÆs going on. In this case the commander would be somewhat isolated from the situation so youÆd have to rely on the crew on site and the senior member there would be the flight engineer. But the flight director in Moscow will be the one in charge of the overall operation. We will be following it very closely with people both here and in Moscow, and if we have questions weÆll certainly be able to raise them and, based on past experience, weÆll get a very quick answer. The actual execution needs to be done by the people who understand it best, and who have been involved in the process all along, and who hold the responsibility for executing it safely, and thatÆs the way weÆll do it, thatÆs the way itÆs been done in every space operation that IÆve ever been a part of or military operation or anything thatÆs being done in a time-critical fashion.ö
