- Press Release
- Mar 22, 2023
Safety Panel to NASA: Build a “Full Envelope” Shuttle Escape System
NASA needs to stop studying crew escape systems for the Space Shuttle and start building them. Moreover, such an escape system should allow the crew to safely depart the Shuttle during all phases of flight – so says the agency’s Aerospace Safety Advisory Panel.
In a rather spirited discussion at NASA Headquarters on Wednesday, NASA Administrator Sean O’Keefe and several members of the ASAP sat down to discuss the recommendations accompanying the committee’s annual report for the year 2002. While the avowed intent of this particular meeting was to discuss the panel’s 2002 report – which covered events in 2002, the meeting quickly – and clearly – focused on the Columbia accident and how the safety of the Shuttle fleet should be improved.
The meeting opened with an overview by the Panel’s chair, Shirley McCarty. She closed with the comment “If you outsource you can’t outsource safety – it is the element that must remain with NASA.”
The first topic discussed was Shuttle aging and certification. Panel member Bob Sieck gave an overview noting that the original requirements established for the Space Shuttle in 1970’s called for 100 flights. “Over time requirements were updated due to experience” he said. “What we found – and this is not new – is that there have been some cases where standard text of the requirements have not kept pace with aging of the systems.”
Sieck then went through a selection of issues that have caused flights to be delayed in the past few years: flex hose issues, cracks in a flow liner – only thousandths of an inch across, leaks in a line that carries liquid hydrogen away from the external tank for burning, and a connector problem in the umbilical cable that carries the signal for the firing of ordinance for the hold down posts for the Shuttle’s Solid Rocket Boosters. All of these items were caught by routine checks – but they are things that might not have been in the minds of the Shuttle’s original designers – especially the fact that the orbiters would still be flying in the 21st century with 75% of their 100 flights yet to come.
O’Keefe then asked “All orbiters are past their certified design life (older than 10 years) but they have only [spent] a fraction of their flight life. Which is the pacing item – age or number of flights?”
Sieck replied that “this is kind of like a car warranty – i.e. you get a car so many years or so many miles. This does not mean you can’t still drive the car but I now have to do something to analyze the system to certify this for another period of time. My observation is that this has occurred in some cases [since 10 years were up I the 90’s] but has not been applied in all cases for all systems.”
O’Keefe then noted that B-52s are now at 3 times their design age but they are still being used. ” [As with the Space Shuttle] their airframe is reliable but the real issue – like the B-52 – is a constant upgrade effort to bring it to a current technology level independent of its age. I do not know which school of thought is more predominant. [But] I get the feeling that the age is more predominant than technology insertion.”
Sieck replied “it is aging – but not so much due to calendar time. I don’t think that the Shuttle’s designers truly understood the environment that the Shuttles face. [For example] that the payload bays would have this much ground work time performed in them. I also think that no one quite understand what these systems will see in the next 20 years.” Associate Administrator for Safety (and former astronaut) Bryan O’Connor added “we need to recertify what the real environment is because we have been fooled in the past.”
O’Keefe made a final comment on the topic “we need to structure this process to answer that issue. We’re still stuck on age issue- an actuarial issue that needs to be addressed.” He also noted that the issue of ‘age’ was one that a lot of people – media and the general public – seemed to latch onto rather easily.
The panel then moved on to the big issue of the day: crew escape systems.
Leading the discussion for ASAP was former astronaut Sid Gutierrez. He noted that in 2000, 2001, and again in 2002, the ASAP made recommendations with regard to crew escape systems for the Space Shuttle. According to Gutierrez, “NASA has studied this – but has not moved to implement. We recommend that NASA complete its studies and either document why it has not implemented guidelines [for a crew escape capability for the Space Shuttle] or expedite deployment of that capability.”
“Finding 02-9: Although progress is being made, there is no commitment to implementing crew escape capabilities for all regions of powered flight.
Recommendation 02-9: Complete the ongoing studies of crew escape design options. Either document the reasons for not implementing the NASA Program Guideline of Human Rating (currently in review) or expedite the deployment of such capabilities.”
The core of Gutierrez’s presentation and the subsequent discussion was a NASA JSC Human Rating Requirements Document which calls for manned spacecraft to provide a .9999 probability of safe return in every 100 missions. According to Gutierrez this is two orders of magnitude greater than what is available with the current Space Shuttle system.
With regard to the additional safety provided by various Space Shuttle upgrades, Gutierrez said that the upgrades “only offer an overall increase of 50%. There are no Shuttle upgrades that offer 2 orders of magnitude. Only a full crew escape system offers that.” Gutierrez said “I cannot understand NASA’s logic for not putting in a crew escape system. If that logic exists, I don’t understand it.”
Gutierrez made mention of escape systems that have been developed over the past 40 years of jet flight noting that they had served pilots well. To illustrate his point, with possible reference to the Shuttle system, he showed a chart which had a picture of the B-58’s escape pod and a drawing of what was considered for ESA’s Hermes space plane in the 1990’s. With regard to the reliability of current jet escape systems Gutierrez said “they are 95% reliable” with a failure of one in twenty uses.”
Gutierrez referred to another escape concept, this time, one that was drawn up after the Challenger accident. “This is based on the DoD’s Discovery capsule shape. We could come up with a design that would weigh less. The ASAP believes that a full envelope crew escape system should be put in place for the Space Shuttle. – means that crew can escape throughout entire range of flight including reentry.
O’Keefe’s take on a solution is to implement the Orbital Space Plane which he hopes will include capabilities that will allow it to be much safer than the current Shuttle fleet. Once the OSP is available, O’Keefe envisions reducing the Shuttle flight rate, perhaps relegating it to a heavy cargo lifting mode with a crew of 2 or so astronauts. This way earlier escape systems such as the ejection seats on the flight deck used during Columbia’s first 4 test flights could be used.
Gutierrez took issue with O’Keefe on the OSP. “I have an old document written after the Challenger accident. It is amazing how well people outside the agency can predict what can happen.” According to Gutierrez, if NASA continues along the path it is pursuing at the same level of risk inherent in flying the Space Shuttle fleet and does so until 2020 “NASA will probably lose one – perhaps 2 more vehicles. We need to have our eyes wide open. I don’t think there is anyone here who thinks OSP will be operational in 10-12 years. What do we do in the mean time?”
Gutierrez noted that the current Shuttle escape system – the pole that extends out of the orbiter’s hatch to allow the crew to bail out is, called a ‘Phase 1 Crew Escape System.’ That was done, according to Gutierrez because NASA did not have the time to create a full escape system as it returned the Shuttle fleet to flight and that they’d do it later with the current pole system serving as an interim solution. Noting the progress since Challenger Gutierrez said “There is no ‘Phase 2 crew escape system’.”
Panel member, and former astronaut Bernard Harris said “we can debate this all day. The bottom line is there were, there are, and there will be technology solutions. I know it is a challenge for the Shuttle program to stop now and change everything – but I think we should look at that.” With regard to the new OSP Harris said ” If we do not have a crew escape system in there- then shame on us. We need to make sure that the next generation vehicle is based not on probability but on ‘assurability’. Harris added later “We need to use the best technology we can to assure that the crew survives. If we cannot do it in Shuttle then need to have that in next vehicle . If we do not do this now – and do some soul searching – we will be in the same place 20-30 years from now.”
Gutierrez said “You need to have your mind open and have your eyes open. You need to know what risk is. We can do a lot on upgrades but it is not going to change much. I do not have an engineering solution but [given that crew escape technology was developed] 40 years ago I would submit that we could do a better job today.”
O’Keefe and Deputy Administrator Fred Gregory both took some exception to the way that the Panel’s recommendation [02.9] regarding crew escape systems.
Gregory said “I see the words ‘no commitment’ – even though NASA and industry have done a lot of work in the past” Gregory took issue with the finding and recommendation saying that the wording left him with the impression that the ASAP was saying that there was a “suggestion that NASA has given up – therefore there is no answer – therefore we will dismiss the opportunity to not look further”.
At this point O’Keefe went down a path familiar to anyone who has heard him talk about safety: “The safest option I have heard is to stop flying and you will guarantee survivability.” Clearly that is not an option in O’Keefe’s mind. “There is a larger issue that we may need to debate: is the risk of space exploration something we really want to examine in a broader public context where we weigh [the benefits of space exploration] against what we think this vehicle portends in terms of its risk – and whether that is acceptable or not. I view human ratings [of spacecraft reliability] the same way that we talk about a 10 year certified life for the Space Shuttle.”
He continued “the larger question is the risk as we have judged it to be today – high – this is a consequence of a being in a very early phase of exploration. Do we accept that or say ‘no’, that is not acceptable and stop flying. In these past 2 months I have thought about it every minute of every day. There is a larger public debate for this question. If that answer is that we continue with space exploration then we need to answer this recommendation in the way it is written as opposed to a preordained response of what the answer must be.”
This question of risk that has been present throughout human history . I ask the indulgence of the panel about being tied to these program guidelines. But the larger question I am posing is do we answer the question logically – and do you accept the risk? Once you get past that point then you can improve things to enhance survivability.”
Gutierrez replied “crew escape [capability] allows you to have your cake and eat it too. It is risky, you can reduce that a lot – even if you cannot make the vehicle itself as safe as you would like.” O’Keefe replied “I view reality of program guidelines in same way as you view OSP deployment.”
Gutierrez did not agree saying “NASA has been studying crew escape since I have been on this panel. If people still studying this [now] I do not think there is a commitment.” Gregory asked if the drawings that Gutierrez showed “are the answer”. Gutierrez replied “No – they are just examples of what has been done. Things were demonstrated 40 years ago that would ought to be able to do again today.”
O’Keefe then jumped in saying that he has “not seen any malice. I have not seen anyone sit back and say I don’t want to look at this because I don’t like the answer. After 9 memorial services this [issue] has gotten my attention. I do not look at this as being frivolous. I do not see people avoiding this. I see people who are flat out stumped [as to what happened]. I disagree [with the wording] of the finding in 02-9 -but I agree with the recommendation in 02-9. We need to look at it in a broader context. We should not be freeze-framed into a guideline of human flight [whose] values are a controlling feature. Now is a real powerful time to have this discussion – i.e. is this risk acceptable?. We need to complete the ongoing studies. That is the operative word – complete.”
Gutierrez said “I did not want to imply that anybody has not purposefully pursued this. I believe that reasoned people can have a spirited debate about this subject. I do not think that this panel is interested in making a recommendation that we stop human spaceflight. I think they are saying ‘let’s lower risk level so that it is more acceptable’. I get the feeling in this country that people think that we are losing people too often in space. The idea that we are going to do some crew escape in the OSP so we can kick the can down the road and not address crew escape in the Space Shuttle is unacceptable.
O’Keefe said “we will look at the options and see what the answer is. Whether or not we accept this a different debate. Gutierrez replied “a study of whether we can do full envelope system in the Space Shuttle should not be affected by the OSP or when it comes online.”
O’Keefe then said “there is also a set of operational questions that must be inserted.” Fred Gregory jumped in saying “if you look at the OSP requirements you will notice that there is no requirement for an ‘orbital escape system’ – but it did establish requirements for ‘orbital safety’ . [This document] has not constrained people to an answer that may be met by escape system – or a capability in the vehicle itself – or something that we have not thought about . I do not anticipate that the next system will talk about ‘crew escape’ – but rather ‘crew survival’ which is almost the same thing.”
Gutierrez replied that ‘at the heart of the recommendation is the NASA culture [view] i.e. . we get crew back if we get the vehicle back. Sometimes it is better sit to worry about getting the crew back. [AS such] a change in culture is required. The NASA culture at the SLEP conference was “our approach is to get the entire vehicle back to get the crew back”. At some point, if we really want to lower risk, we need to have a different culture and mindset.” O’Keefe replied “I can’t tell if things can be improved by changing the culture or not. Let’s put the full range of issues on the table.”
Having used up nearly the entire 2 hour time slot for the crew escape issue, the panel quickly moved on to other topics.
Panel member Robert Francis praised O’Keefe’s selection of Admiral Gehman to chair the Columbia Accident Investigation Board (CAIB) but questioned the process wherein CAIB members were selected according to their jobs. O’Keefe replied, somewhat incredulously, asking Francis if he was suggesting that selecting these people for the CAIB might be an issue “because they might not be competent?” Francis replied ” they may not be prepared for what they are being asked to do.”
The panel also expressed its concern that until the advent of the OSP the ISS will be limited to crews of 3 since the single Soyuz present at all times can only carry 3. The panel was concerned not only about the availability of funding for Soyuz vehicles up to 2006, but the gap that will exist between 2006, when the current Russian agreement to provide Soyuz vehicles as part of their participation in the ISS program comes to an end and 2010, the earliest date the OSP is expected to come online. “this has not been resolved” said panel member Cantrell but this issue has moved along since the ASAP report was drafted (due in part to the Columbia accident).
Walter Cantrell also expressed the ASAP’s concern that funding for the micrometeoroid and debris program has been resolved. He also mentioned an issue of safety and the International Partners. According to Cantrell, a hazardous situation arose when the Russians sent some batteries up on a Soyuz which were volatile and toxic. This shows an instance where the safety system broke down – something that needs to be attended to.
Editor’s note: as far as advisory panels go, the ASAP really brushes up against the edge of what is and is not in the purview of a ‘advisory’ panel and really pushes NASA to do certain things – much more so than do other FACA (Federal Advisory Committee Act or “Sunshine Act”) panels. Some might argue that on the issue of safety, especially in light of the Columbia accident, findings and recommendations should be driven home with a special amount of direct emphasis.
On the other hand, there are programmatic realities that may constrain the ability of NASA to do things thus forcing them to seek alternative means to accomplish the same end result. Whether the Shuttle fleet will be augmented with a robust, ‘full envelope’ crew escape system or made as safe as they can while a new, more capable system (the Orbital Space Plane) is rushed into operation, remains to be seen.
Sadly, at the end of the day, this is not about committment (or lack thereof) on anyone’s part to crew safety. Rather, this is driven partially by the amount of money that is available and, as O’Keefe has suggested, what level of risk astronauts, the agency, and the American people are willing to take as we explore space. Out of this mix a plan will eventually emerge – I think everyone knows that this is owed to the crews of Columbia and Challenger.