SpaceX, NASA Discuss Forthcoming Dragon Pad Abort Test

SpaceX Vice President of Mission Assurance Hans Koenigsmann (left) and NASA Commercial Crew Program Partner Manager Jon Cowart take questions during today's Pad Abort Test Briefing at the Kennedy Space Center (KSC). Photo Credit: NASA
SpaceX Vice President of Mission Assurance Hans Koenigsmann (left) and NASA Commercial Crew Program Partner Manager Jon Cowart take questions during today’s Pad Abort Test Briefing at the Kennedy Space Center (KSC). Photo Credit: NASA

Barely a week since the successful launch of the TurkmenÄlem52E/MonacoSat payload to Geostationary Transfer Orbit (GTO), SpaceX will again rock Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla., to the roar of rocket engines on Wednesday, 6 May, when it executes the long-awaited Pad Abort Test of its soon-to-be-crewed Dragon spacecraft. The test forms one of SpaceX’s Commercial Crew integrated Capability (CCiCap) requirements, ahead of its 2017 goal of returning U.S. astronauts to the International Space Station (ISS), aboard a U.S. spacecraft, and from U.S. soil, for the first time since the end of the shuttle era. Earlier today (Friday, 1 May), two key figures—NASA Commercial Crew Program Partner Manager Jon Cowart and SpaceX Vice President of Mission Assurance Hans Koenigsmann—spoke at length about the intricacies of the test and its importance in the Commercial Crew endeavor. Follow AmericaSpace’s Launch and Events Tracker for updates and live coverage of the Pad Abort Test.

The test was originally scheduled for early-April, but was postponed due to schedule slippage of the higher-priority TurkmenÄlem52E/MonacoSat, following the discovery of an issue with a batch of Falcon 9 v1.1 helium pressurization bottles during testing. As a precautionary measure, the TurkmenÄlem52E/MonacoSat mission slipped until late-April, with the Pad Abort Test anticipated a few days thereafter. Both events were slated to originate from SLC-40. “We have more flexibility with the Pad Abort schedule,” SpaceX told AmericaSpace recently, “so we’re evaluating the best dates in light of the two missions.” The Dragon spacecraft assigned to the Pad Abort Test was delivered to the Cape in February 2015 for final processing, ahead of integration with a supporting truss structure at SLC-40.

Last month, it was announced that the test would occur no sooner than Tuesday, 5 May, during a four-hour “window,” due to open at 9:30 a.m. EDT. “The ability to abort from a launch or pad emergency and safely carry crew members out of harm’s way is a critical element for NASA’s next generation of crew spacecraft,” it was explained in NASA’s Media Accreditation literature. “SpaceX will perform the test under its Commercial Crew integrated Capability (CCiCap) agreement with NASA, but can use the data gathered during the development flight as it continues on the path to certification. Under a separate Commercial Crew transportation Capability (CCtCap) contract, NASA’s Commercial Crew Program will certify SpaceX’s Crew Dragon, Falcon 9 rocket, ground and mission operations systems to fly crews to and from the International Space Station.” Earlier this week, however, it was announced that SpaceX would be targeting the second opportunity, on Wednesday, 6 May, for the test, which is anticipated to get underway at 7 a.m. EDT, at the opening of a four-hour window.

SpaceX's Crew Dragon spacecraft is prepared for the critical Pad Abort Test. Photo Credit: SpaceX
SpaceX’s Crew Dragon spacecraft is prepared for the critical Pad Abort Test. Photo Credit: SpaceX

In his opening remarks from the TV Press Site Auditorium at the Kennedy Space Center (KSC), Fla., Dr. Koenigsmann exulted that he was “super-excited about this test” and that it represents “what SpaceX was basically founded for: human spaceflight.” He noted that it would demonstrate a “revolutionary system for the safety of the astronauts.” Mr. Cowart added that NASA and SpaceX have been “working towards this point for four years,” ever since the initial award of the CCiCap contract. “These are the days we live for,” he told his KSC audience, pointing out that “there’s gonna be some smoke and fire,” but cautioning that it was a development test, “not a shiny, well-polished Space Shuttle launch.” However, the importance of the Pad Abort Test is inescapable. “Let’s go test!” exclaimed Mr. Cowart. “One good test is worth a thousand expert analyses.”

As already described to AmericaSpace by SpaceX, the test will be a short and rapid one, lasting under two minutes from pad departure through splashdown in the Atlantic Ocean, with most of that distance covered in the initial 25-30 seconds. “I can hold my breath the entire time!” quipped Dr. Koenigsmann. The instrumented Dragon crew module—whose payload includes a crash test dummy, named “Buster”—and the unpressurized trunk will be mounted atop a simulated upper segment of the Falcon 9 v1.1 rocket and a steel truss framework, which has been installed directly over the flame trench aperture on SLC-40. The overall weight of the stack will be in excess of 21,000 pounds (9,525 kg), plus around 3,500 pounds (1,590 kg) of propellant. The steel catenary lines at SLC-40, which are normally utilized as a high-level lightning protection mechanism during Falcon 9 v1.1 launches, have been removed for the purposes of the Pad Abort Test.

Wednesday will be the first time that a full complement of eight SuperDraco thrusters for the piloted variant of Dragon have ever been ignited together. Fueled by a combination of storable monomethyl hydrazine and nitrogen tetroxide, each of these 3D-printed thrusters is capable of around 16,400 pounds (7,440 kg) of thrust—thereby punching out a total propulsive yield in excess of 120,000 pounds (54,430 kg)—which Dr. Koenigsmann described with a charismatic grin as “a lot of kick.” By comparison, the SuperDraco is around 200 times more powerful than the Draco thrusters currently used by the unpiloted Dragon cargo spacecraft. Last May, SpaceX announced that it had completed qualification testing of the SuperDraco at its Rocket Development Facility in McGregor, Texas, during which the thruster was put through a range of conditions, including multiple starts and extended-duration firings, as well as exposing it to extremely off-nominal propellant flow and temperature scenarios.

An advanced 3D printed SuperDraco engine, the same which will fly on the piloted Dragon spacecraft, conducting qualification testing at the company's Rocket Development Facility in McGregor, Texas last month. Photo Credit: SpaceX
An advanced 3-D printed SuperDraco engine, the same which will fly on the piloted Dragon spacecraft, conducting qualification testing at the company’s Rocket Development Facility in McGregor, Texas last month. Photo Credit: SpaceX

Unlike previous launch abort systems, which were typically discarded a few minutes after liftoff, the SuperDraco thrusters are built into the side walls of the Dragon spacecraft and are available for use not only as an escape mechanism for the crew in the event of a contingency, but also can be employed throughout the later stages of ascent or for a propulsive landing. Responding to questions at today’s press briefing, Dr. Koenigsmann explained that it is “different to run thrusters in the air, under atmospheric pressure” and added that the Pad Abort Test is “a development test; it’s a brand-new vehicle.” Meanwhile, Mr. Cowart—who will serve as NASA Mission Manager for SpaceX’s first crewed Dragon V-2 mission in early 2017—concluded that Wednesday’s test will be the first occasion that more than two SuperDracos have been fired in unison. “All the indications are that it’s going to do a super job,” he said.

Since the Pad Abort Test will not utilize a Falcon 9 v1.1 booster, the Dragon will be launched “almost from ground level,” according to Mr. Cowart, with water from the 53 nozzles of the Niagara sound suppression system flowing inward from the sides. An early-morning flight was preferable, in the context of historical Florida weather, although Dr. Koenigsmann pointed out that wind speeds will be a carefully monitored concern. Under the propulsive influence of the eight SuperDracos, the Dragon crew module and unpressurized trunk will be boosted at high velocity away from SLC-40, pitching toward the east and reaching an altitude of 5,000 feet (1,500 meters) within just a handful of seconds.

Although the ascent will be rapid, Mr. Cowart explained that from a Range Safety Officer (RSO) perspective, “compared to a rocket it can’t get very far” and that the flight would likely occur within a relatively small radius of about 2.2 miles (3.5 km). A couple of seconds after reaching apogee, the trunk will be jettisoned from the crew module. The latter will then begin the process of deploying a pair of reefed drogue parachutes, followed by a trio of main canopies about 30 seconds later, which will effect a splashdown in the Atlantic Ocean, somewhere between 90 seconds and two minutes after leaving SLC-40. Splashdown is expected to occur about 6,000 feet (1,800 meters) to the east of SLC-40, which will place its impact point about 3,000 feet (900 meters) out to sea.

SpaceX's Dragon capsule can hold seven astronauts in its crew configuration. Photo Credit: SpaceX
SpaceX’s Dragon capsule can hold seven astronauts in its crew configuration. Photo Credit: SpaceX

Notwithstanding the fact that the crew module is heavily instrumented for this test—specifically, with gyroscopes, temperature sensors on the exterior hull to measure heat fluxes, acoustic sensors, and cameras—a great deal of interest has centered on the presence of a crash test dummy, which will be strapped into a seat aboard Dragon. The other six seats will be weighted to simulate the presence of a full crew. It is expected that the dummy will be subjected to peak G-loads of up to 4.5 G during the most extreme points of the ascent. Last week, Voice of America reported that the dummy is nicknamed “Buster” and its contribution and those of the other instrumentation will be a critical asset as SpaceX and NASA move toward full certification of the spacecraft, which is expected to fly unpiloted in late 2016 and in a crewed capacity sometime early the following year.

Looking beyond Wednesday’s test, Dr. Koenigsmann and Mr. Cowart were questioned about the kind of success criteria they expected to see and how this will factor into future plans, most notably for the upcoming In-Flight Abort. The latter will employ the same Dragon crew module as that used in the Pad Abort Test, but will venture to an altitude of 40,000 feet (12,200 meters) in what Dr. Koenigsmann described as “a very elaborate test” to investigate its performance under high aerodynamic loads at “Max Q.” The two panelists replied that this second test—which SpaceX intends to stage later in the summer from Space Launch Complex (SLC)-4E at Vandenberg Air Force Base, Calif.—will offer an opportunity to repeat any necessary tasks.

“There’s all gray areas in success,” noted Mr. Cowart, drawing an apt analogy with the famously oxymoronic description of Apollo 13 as a successful failure. “No matter what happens on test day, we’re going to learn a lot,” he emphasised, adding “We’re doing something historic here.”

 

 

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29 Comments

  1. In light of a recent discussion on another thread, it will be interesting to see how The hypergolics affect handling issues as well as safety.
    It would be a nice thing to see how the test affects comments by proponents of other escape systems. Eliminating the staging event of heritage systems should be a step forward.

    • In light of….

      Adding a staging event and throwing away useful propellant and hardware that has already been boosted is a superior solution?
      • Gary Church
      April 24, 2015 at 6:55 pm • Reply
      “Throwing away” a tower after the second stage has ignited adds quite a bit of payload and get’s rid of the escape system that was needed sitting on the pad, during ignition, during the initial lift-off, through Max-Q, and during staging and ignition of the second stage. That “useful propellent and hardware” is no longer of much use at that point- but getting rid of it after second stage ignition is very useful for increasing payload.
      It is the superior solution and will remain so. There were very good reasons it was adopted and loading up the capsule with hypergolics and engines was not- and those reasons are as valid today as they were over half a century ago. Nothing has changed- it is the same supremely toxic propellent. Even if it was not toxic the reasoning is flawed- the capsule is not the place to store that much propellent.
      It is an attempt to make money by trading crew safety for a dual purpose system useful for orbital maneuvers (such as keeping tourist space stations in the right orbit).

      “This gives SpaceX’s launch escape system many advantages over past systems. It is inherently safer because it is not jettisoned like all other escape systems. This distinction provides astronauts with the unprecedented ability to escape from danger at any point during the launch, not just in the first few minutes.”
      SpaceX advertising continues to insult the intelligence of anyone with a basic knowledge of space flight.
      This is much like their claims of what a superior propellent kerosene is compared to hydrogen. Actually the large-booster solid fuel technology and the hydrogen turbopump technology were both too expensive so they went cheap.
      And their claims that using 9 crummy little engines is superior to using one because it allows for an engine failure. Actually it completely violates the KISS principle and was again a case of simply going cheap.
      Now this escape-system-that-is-not-an-escape-system. Actually it is “inherently safer” to jettison the escape system after the second stage lights off; all the really dangerous flight regimes, including just sitting on the pad (a pad fire is a significant danger), are past. Instead of getting rid of a relatively safe and very simple solid fuel/tower assembly to increase payload the crew is stuck in a far more complex vehicle loaded with toxic explosives.
      The adjective “Orwellian” comes to mind.

  2. Not trying to be belittle anyone but I find the discussion regarding hypergolics somewhat amusing. I have seen similar comments elsewhere. I worked OMS/RCS on Shuttle. Everyone worked themselves into a mindless frenzy regarding hypers except us and the APU guys. We just went along and got the job done.

    Granted precautions have to be taken but it really is no worse than about a lot of things in spacecraft. Look at what happened with a relatively benign substance like nitrogen.

    • I wouldn’t have a problem with actual knowledge belittling my ignorance on the subject. I’ve just heard and read second hand accounts of the problems with the stuff for quite a number of years. I assumed that the stuff was quite nasty enough for concern, though possibly nowhere near as bad as the troll was raving about.

      Thanks for injecting a bit of reality. From your comment though, it seems that it is fairly common for people to have an excess of caution regarding the hypergolics. In your experience, what is the best answer to someone that is terrified of them?

    • Well, I have heard the exact opposite from two posters recently on this site on the hypergolic propellants on Dragon V2. One thought that the 270-pound load carried on the Apollo CM was safe but was ballistic (no pun intended) about the prospects of ~3,700-pounds of hypergolics on the Dragon V2. He was unable to provide any rationale for a dividing line between “safe” and “unsafe” loads (and rather hostile that I would even ask for one since I have no clue about his level of expertise). Yet another poster claimed that there is no safe load… period. A much calmer exchange followed with the usual safety issues recited along with discussion with others about the state of technology of safer alternatives (e.g. kerosene/LOX).

      Needless to say, I am prone to take the word of an expert (especially without the benefit of any access to engineering trade studies on the Dragon) but still I wonder if SpaceX has made any public statements specifically addressing this issue.

      • Andrew,

        Since I think I was part of what you called the “calmer exchange”, let me restate what I was trying to say.

        I did not say hypergolic propellants can not be dealt with, but that if you are using them in a reusable crewed vehicle they will complicate things. That complication will increase turn around time and cost and that is a problem for SpaceX due to the very high flight rates Musk keeps promising.

        Since we are apparently going to get into comparison of resumes and war stories, when I was first out of collage my first job was in Shuttle EVA hardware. On one flight during that period a problem was noted with the thermal blankets on one of the OMS Pods. It was feared that this could cause problems upon reentry and one of the possible fixes involved an EVA in the vicinity of the Pod.

        The problem was that hydrazine in vacuum turns into a fine white powdery ice. That ice could attach itself to the Pressure Suit TMG, harmless while at vacuum but when returned to the airlock potentially deadly.

        A tech I was working with came up with a brilliant idea of using storage bags from the mid deck to make a sort of deposable coverall to protect the TMG. I remember it well because when I brought it to the attention of my bosses, bosses, boss; I got tasked to work the manufacture with the tech and then work with the people in flight ops to write a set of instructions to be sent to the crew. Was up more than 30 hours straight and I was not alone. We “got the job done”, but do not remember anyone during that episode being “amused”.

        Fortunately, the kludge never had to be used.

        To end on a more amusing note the incident did produce one good joke. In the aftermath the White Sand folks who do hazardous materials handling were ordered to deliver a detailed list of the safe handling of hydrazine procedures. One of the lengthy list of instructions read – Never drink hydrazine.

        That, of course, only lasted one day before it had been changed on the officially posted version to – Never drink hydrazine, on an empty stomach.

      • “He was unable to provide any rationale for a dividing line between “safe” and “unsafe” loads (and rather hostile that I would even ask for one since I have no clue about his level of expertise).”

        You have continued to bully and harass me since I began posting on this site some weeks ago. You do not like my views on space exploration and you seem determined to hound me off this forum. I have repeatedly warned you that your constant negative replies are inappropriate- and stated clearly and unequivocally- I want you to stop cyberstalking me Andrew.

        You are a bully and a liar and every single time you make these remarks about me I am going to expose what you are doing.

          • I am taking it up with you- stop harassing me and we will get along just fine. You post your comments and I will post mine. If you continue to try and humiliate me with disparaging comments and naysaying my comments with negative replies I will continue to take it up with you every time you do it because you are a liar and a bully and I am not going to let you get away with it. Is there something you do not understand about the clear message I am communicating to you to LEAVE ME ALONE?

              • I did Andrew. Regardless of what he decides, every time you try and play your sick game with me I am going to throw it back in your face- every single time. Just leave me alone and none of that will be necessary.

  3. “-nowhere near as bad as the troll was raving about.”

    Not taking the bait you thug.

  4. All the best SpaceX. Great to see a company finallychallenging the status quo.
    Gary, it’s a pity you have to continually denigrate SpaceX after all they have achieved. You must live a sad life full of negativity and darkness. My sincere sympathies.
    Kind regards,
    Neil

    • The negativity and darkness is all from you SpaceX fans, thanks. I am actually a pretty happy guy except for having to deal with the creeps that worship Musk and their incessant and endless cyberthuggery- of which your comment- designed to shame and humiliate- is typical. Disgusting.

  5. The toxic dragon launch abort system was a waste of 70 million taxpayer dollars. It is anemic compared to the half a million pound thrust escape tower of the SLS. It was perhaps the only solution for SpaceX though since escape towers are heavy- and the hobby rocket is a mediocre lift vehicle. Anybody who thinks this monstrosity is going to be making regular landings is completely deluded. In a minor crash it makes a mockery of crew survivability and turns the immediate area into a lethal toxic hazard. Of course, those who think reusing stages is going to be cheaper than dropping them in the ocean are also living in a fantasy world. It is all a scam to keep the public in awe of the great innovation going on; it will take years to prove what those with any understanding of the rocket equation already know- reusability is a myth. Hyperloopy Tony Starks and tourist space stations in the dead end of LEO- the abomination called NewSpace.

      • “The only one I see being a bully on here is you.”

        And anybody reading your reply to my comment is wondering what you are babbling about since I did not bully anyone in my condemnation of that waste of tax dollars.

        Unless you hold that a corporation is a person with feelings that can be bullied. Which, considering the NewSpace cult of Ayn-Rand-in-Space-dollar-sign-worshiping-freaks that claim to be space advocates, could be what you are doing.

        • I have seen this name “Gary Church” in comments on many websites – You are always the aggressor and the one being a bully and harassing others who disagree with you.

          • And anyone who goes to any of those websites will see that I am the one being insulted, bullied and harassed by NewSpace fans who cannot stand anyone criticizing SpaceX, Musk, or the LEO business plan being pushed by this administration.

            Kindly cite these comments and show the truth of your comment- cut and paste if you wish but provide a link with it that shows the context. I act exactly like the NewSpace sycophants do- I make it a point to be just as acid and sarcastic- and I am then singled out as a bully. It is disgusting.

            So go ahead Jester and show everyone what a bully I am with examples. Let’s see it.

  6. Hello Billgamesh..er Gary.
    Sorry the other guy hated “NewSpace” drones, SpaceX lovers, low cost boosters and
    “bullies”. And that guy kept getting thrown off of space web sites for Trolling.
    But that’s not you so… not relevant, eh?

    The fuel that you are criticizing has been in use for decades and can be stored safely for months in a vehicle’s tanks (you can’t do that with LOX, H2 or any cryogenic). It is a pain to handle but once stored, it is quite well behaved (and while highly exothermic, is not combustible).

    It throttles Very quickly from 0 to 100% power and that’s kind of what you need for escape systems. And it can throttle down All the way to 0 again (which you really want for controlled landings) – most engines can’t approach that and have too much minimum thrust.

    And it can be refueled just like any other engine, so not a big deal – if you think LH2 is a joy to handle, please think again…. and it Can’t be stored for any length of time before it seeps out of its tanks (diffusing right through the metal matrix even if the seals are perfect).

    Sea landings force salt water up into rocket engines and leave brine and cause valve blockage issues (corrosion aside). Would you want That in your turbopumps?
    Disassembling a rocket engine for cleaning is expensive.
    Drenching a super hot heat shield in cold brine is also bad.
    Sea landings are Not good for reusability as Boeing acknowleged, preferring air bag bump down landings (despite the risks) for CS-100.

    Reusability of a manned ship as a cargo carrier (if NASA has problems with it being otherwise reused) would save a Lot of money.

    A fully throttleable, fully redundant propulsive landing is in no way far fetched, especially with a parachute to use in conjunction (if even needed). I could Hardly imagine a more safe craft to land in (effectively triply redundant).

    As for SLS:
    12 Billion dollars to develop a craft cobbled together with spare shuttle parts to use once a year or less… this may not even exist 5 years from now depending on the winds of politics.
    It is literally one senatorial seat from the chopping block.
    And when the stock engines run out? They are a pain to manufacture and no one does it today.

    (Actually, I liked the Idea in concept, but for the money, I hate the execution.)
    Like it or not, SpaceX is making all the other Space launch companies reduce prices dramatically. Without that necessary step, real space exploration is just a pipe dream fueled by congressional pork. (Since When does congress determine the exact rocket engines that a new booster should use….. really. Complex reusable engines strapped to a one-use rocket… What the heck?!)

    Mars?…. I don’t really see the point of that when all the math is done. But a mining colony on the moon! That I would like to see in my lifetime…. and now I probably will.

  7. “And that guy kept getting thrown off of space web sites for Trolling.
    But that’s not you so… not relevant, eh?”

    Thrown off for criticizing Musk, SpaceX, and NewSpace; that freedom of speech is presently only tolerated on America Space and Spudis Lunar Resources to the best of my knowledge.
    Relevant enough for you to try and embarrass me with- show’s what a creep you are.

    “-can be stored safely for months in a vehicle’s tanks (you can’t do that with LOX, H2 or any cryogenic).”

    It is the only type of standard rocket propellent combination that can be stored and used in restartable engines- which is why it is the only choice for keeping space stations in orbit. Otherwise they would not be forced to use it. That SpaceX is being devious about what the toxic dragon is going to actually do is a huge red flag. Wait and see. The truth will out.

    “And it can be refueled just like any other engine, so not a big deal-”

    Tell that to the guys in full hazmat rig who have to do it. It is a big deal. As for hydrogen exfiltrating that is an acceptable disadvantage for launching from Earth- it is the ultimate propellent and there is no substitute.

    “Sea landings are Not good for reusability”

    Worked for the Shuttle SRB’s. For 30 years. That simple steel casings did not break even for reuse is a clue that it is reusability that is the problem- not seawater. Staw Man. There is really no way to beat a couple hundred pounds of parachute and floats and a whole ocean to land in.

    “-propulsive landing is in no way far fetched, especially with a parachute to use in conjunction (if even needed). I could Hardly imagine a more safe craft to land in-”

    It is actually “far-fetched” in every way and that it is not done after a half a century of trying is proof of that. The engines and propellents have not changed. You might want to google “cognitive dissonance.”

    “SpaceX is making all the other Space launch companies reduce prices dramatically.”

    Propaganda. Actually, SpaceX prices are inexorably climbing and if NASA support was removed it is not clear if they could be competitive with “all the other Space Launch companies” (that would be ULA). Applauding SpaceX for ULA developing new hardware is….not valid since the entire Russian engine saga is just DOD bad business as usual. The Muskiiah did not save us from Russian engines- he just wants those DOD dollars that ULA has been getting. Unlike ULA launchers the hobby rocket is an inferior lift mediocre vehicle and while using NASA dollars to establish a commercial satellite launch company- and essentially scamming the taxpayer- they are charging 36,000 dollars a pound to deliver to the ISS- and have done little else.

    “Without that necessary step, real space exploration is just a pipe dream fueled by congressional pork.”

    Absolutely Orwellian; SpaceX is the poster child for pork because without the space station to nowhere SpaceX and the whole NewSpace business plan would not exist. The Columbia disaster and 100 billion dollars in tin cans going in endless circles that could not be admitted a dead end gave birth to the abomination that is NewSpace- and the damage to space exploration accumulates with each new sordid chapter. Real space exploration is Beyond Earth Orbit and there is only one hope for that- SLS/Orion.

    The mob of deluded sycophants cheering it all on will one day be reviled and held in contempt. Congratulations.

    • “Real space exploration is Beyond Earth Orbit and there is only one hope for that- SLS/Orion.

      The mob of deluded sycophants cheering it all on will one day be reviled and held in contempt.”

      Once again, these sentences do not follow each other well and I really wish there was a temporary edit feature in this comments section.

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