Chair Force Engineer

Monday, July 30, 2007

In Memoriam

It's taken me a while to put together anything to say about the Scaled Composites tragedy. Unlike a lot of the voices in the blogosphere, I never knew the men involved. That has made it difficult for me to add anything to the memorials that have already been delivered so eloquently.

I can only speak to what I have seen from the hard-working and dedicated technicians I have observed. Recently, I was teaching the Space Exploration merit badge to a group of Boy Scouts. One of the things I stressed was the role of technicians in making the world go 'round. For everybody who gets the glamorous job of "riding the rocket," there are a thousand people standing behind that astronaut and making sure that everything runs like it should. Eric Blackwell, Todd Ivens, and Charles "Glen" May stood behind SpaceShipOne as it made its magical campaign to win the X-Prize, and they poured their souls into its successor, SpaceShipTwo. It is in that spirit that we celebrate their lives, and the spirit in which we pray for the recovery of Keith Fritsinger, Gene Gisin, and Jason Kramb.

Some people have commented that this accident ends the honeymoon that space tourism has enjoyed, and that this emerging field had somehow lost its innocence. The horrific accident last week wasn't inherent in the nature of the space business. It was an industrial accident that could happen with anybody who was working with pressurized gas. It was indeed a tragedy, but it should not be exploited as a way of regulating into obscurity the cause that Eric, Todd & Glen devoted their lives to.

When Columbia was lost, I took note of God's covenant with Abraham, that his descendants would be as numerous as the stars. I also like to interpret that covenant as a statement on mankind's destiny, that we will live among the stars. The tragedies we have faced since then cannot derail us from that destiny. At this time, I should add that we are giants, because we stand on the shoulders who have come before us. The first human to be born off this earth will owe a small token of gratitude to men like Eric, Todd and Glen. They lived on the leading edge of the new space revolution. Their sacrifice will not be in vain.

Wednesday, July 18, 2007

Rescue Fraud?

Originally, I was looking forward to seeing the movie Rescue Dawn. I mean, it combines a real-life POW drama with Christian "Batman" Bale. What could go wrong with that?

Apparently, quite a bit. It would appear that the filmmakers have strayed very far from the real events. The net effect is that the main protagonist, Dieter Dengler, is elevated to demi-god status, while the other equally-brave men who tried to flee with Dengler are shamefully denigrated.

How am I making my voice heard to the purveyors of this historical farce? I'm not going to see this charade of a a movie. Director Werner Herzog can take my nine bucks and shove it up his krauty ass.

Monday, July 16, 2007

Stuck on the Pad

The comments section on Transterrestrial Musings brings out some interesting statements, especially on the post about Scott Horowitz's departure from NASA.

Interestingly, one commenter claims that United Launch Alliance is pitching a replacement for the 5-segment SRB, and it looks an awful lot like the Atlas V Phase 2 (5.4 meter core, 2x RD-180.) According to the commenter, this would eventually be developed into a flyback booster and used on the Ares V as well. Would NASA really be serious about developing a kerosene-fueled alternative to the shuttle SRB, and dealing a major blow to ATK's solid rocket business?

As pleasant as that fantasy sounds, it won't be happening. For one thing, the booster would be quite underpowered. It takes the thrust of three RD-180's to approximate the thrust of one Shuttle SRB. While I have no doubt that the booster described above (5.4 meter core + 2x RD-180, 5.5 meter upper stage + 1x J-2X) would work, it would fall short of the criteria that NASA used to design Ares I in the first place. Its thrust-to-weight would be too low to fly the depressed trajectories that NASA wants (to eliminate "black zones" where an abort would place unsurvivable stresses on a crew.)

Development of the hypothesized booster would be pricey. It would likely cost more than the 5-segment SRB, and it would dwarf the cost of completing the development and man-rating for the Atlas V Heavy. While the hypothesized booster would have commercial applications, I don't believe that taxpayer dollars should be used to subsidize a large portion of the booster's development costs (especially when we have a post-shuttle spaceflight gap that needs to be closed.)

The flyback booster idea has merit in the long term, but it's unlikely to be realized anytime soon. While flyback boosters have been on the drawing boards for the last 45 years, none have actually been built. Such a task is easier said than done. Development of a flyback booster should be conducted as an X-Plane program, jointly sponsored by NASA and the Air Force. Such a booster would have to pioneer deceleration and transition to a glide at altitudes around 100,000 feet and speeds between Mach 3 and 6. It would need a structure that can handle the massive thermal swings between cryogenic temperatures and hypersonic heating. It would need a turbine propulsion system that could survive the flight and then activate for the final approach to the runway, and it would need a reliable guidance system that could bring it back to base and touch down for a smooth landing in a variety of weather conditions. Flyback boosters are a high-risk, high-payoff technology that has been woefully underfunded over the years. If we want to be back on the moon by 2020, flyback boosters will not be part of the initial plan.

It would be nice to see the post-shuttle spaceflight gap reduced to just two or three years. The only way that will happen is by leveraging Shuttle, Atlas and Delta components that already have flight history. The Shuttle SRB, or a 5-segment derivative, will certainly be part of that future. The "back to basics" approach is why I support DIRECT. I could also get behind the Atlas V (with 3, 4 or 5 Aerojet SRB's) for crew launch to ISS, if the mass and size of the Orion capsule can be cut down to fall within the Atlas performance envelope.

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Thursday, July 12, 2007

My Wife & Kids?

I was somewhat surprised to see Scott Horowitz resign as NASA's Associate Admin for Exploration Systems today. Even more surprising is the reason he cites for his resignation: to spend more time with his family.

When public officials cite family as a reason for resignation, it usually means that there are other, more unseemly reasons behind the decision. Example: one of the few politicians I've ever admired, Senator Peter Fitzgerald of Illinois, declined to seek re-election in 2004 to 'spend more time with his family.' Of course, he was facing a stiff re-election challenge, and his party made it clear that they would not support the "maverick" senator.

With that being said, are there ulterior motives behind the resignation of Scott Horowitz? It can't be overstressed that Scott Horowitz has been the single most important proponent of Ares I. Until now, Ares I has been forced to withstand two years of criticism from snarky malcontents like myself. But now the launcher's performance shortcomings are becoming publicly apparent. Orion is just too heavy to be launched by Ares I, unless performance margins are sacrificed and capsule weight drastically reduced.

The departure of Scott Horowitz leaves one question in my mind. Is he leaving so NASA can find somebody else to bring Ares I and Orion back on track? Or is Scott Horowitz stepping aside so NASA can examine an entirely different approach for launching Orion? Michael Griffin's choice for Scott Horowitz's successor will answer the questions behind the departure of the man who fathered Ares I.

Tuesday, July 10, 2007

Tightening Orion's Belt

Observers of NASA's Vision for Space Exploration are well aware that the Orion capsule is suffering from major mass issues at a disturbingly-early stage in its development. But this problem begs the question of whether the materials going into Orion are the correct ones to begin with.

One suggestion is that, for purposes of crew safety, a titanium structure should be used instead of the Aluminum-Lithium alloy in the current baseline design. If enough Orions are flown, there's a significant chance that a Soyuz 5-style reentry will occur. Orion, with the baseline Al-Li structure, will probably not survive a reentry where the service module fails to separate and the non-shielded surfaces of the command module bear the brunt of the re-entry heating during the initial phases of descent. Readers may recall that early in the Columbia accident investigation, it was suggested that future spacecraft (Orbital Space Plane, at that stage) would have a Titanium crew cabin that could maintain its integrity until the crew could reach an altitude where they could escape if a reentry failure occurred. NASA seems to have forgotten this lesson.

The Titanium structure deserves to be studied by LockMart as they go through the Orion design process. I would caution that the Soyuz 5 example is not entirely applicable to Orion, as Soyuz 5 was only re-entering from a low earth orbit, as opposed to a faster lunar reentry. LockMart may find that Orion will be prohibitively heavy if it's designed to survive a hatch-first reentry from lunar velocities. Perhaps these studies have already been performed, and simply not publicized.

In any event, a structure designed for hatch-first reentries will probably add to Orion's mass problems. Mass has been the bane of Orion since day one. It was assumed that advances in materials since the early 60's could allow us to build a bigger version of Apollo without significant increases in mass over the original. I think NASA is learning the hard way that this was not a safe assumption to make. It should also be noted that the Apollo CSM massed between 14.8 and 30 metric tons, depending on whether it was staying in earth orbit or flying to the moon. NASA has only budgeted 26 metric tons for Orion's mass, including roughly 4 metric tons that will be used for Orion's orbit insertion burn after it separates from Ares I.

The smartest way to solve Orion's mass issues is not to sacrifice safety or other items that would be "nice to have." Orion can be made lighter if it weren't so wide in the first place. The Apollo Command Module provided astronauts with 5.9 cubic meters, or 1.97 cubic meters of volume per occupant. Orion should be no different. For a crew of four, a capsule of only 4.4 meters diameter should be sufficient, assuming that interior volume is proportional to the cube of diameter. Assuming that Orion is designed just like Apollo but scaled up by a factor of 11.3%, the interior volume increases to 8.47 cubic meters, giving the astronauts almost 2.12 cubic meters per occupant. When combined with the LSAM volume, this should be more than sufficient for lunar transits.

For 6-man ISS missions, the 4.4 meter capsule would only give the crew 1.41 cubic meters per astronaut. For the ISS missions, Orion will only be away from the ISS for a short period of time, so the extra volume really isn't needed. If a Skylab-style mission profile is adopted, Orion can rendezvous with ISS after just three orbits. If the additional volume is deemed necessary, Orion could always include a pressurized Orbital Module, similar to that used on Soyuz & Shenzhou. The Orbital Module would be a stripped-down version of the LSAM ascent cabin.

Perhaps my conclusions are best justified by the pre-ESAS trade studies, where Boeing and Andrews Space both settled on 4.5 meter capsules, and SpaceHab proposed a 4.3 meter capsule.

Regardless of what happens with Orion, it will create a ripple effect with Ares I. After all, NASA baselined a 26 metric ton spacecraft and a launch vehicle that could put exactly as much into the required transfer orbit. The performance margins on Ares I are very tight, and weight growth on Orion will certainly force future redesigns of Ares I. Since the first-stage performance is virtually set in stone, all enhancements must be made to the liquid-fuel upper stage, or by adding a "Zeroth Stage" consisting of solid rocket motors used in the Delta family.

NASA and LockMart's attempts to dig themselves out of the hole they've dug will be interesting, to say the least. I just hope that the final product will be safe, even if it's neither simple nor soon.

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Saturday, July 07, 2007

Roswell That Ends Well

The cow-town of Roswell, New Mexico is hosting its Alien Festival this week, commemorating the 60th anniversary of the fabled UFO crash. Shaking things up is the recent disclosure of an affidavit from Walter Haut, the public affairs officer at Roswell Army Air Field in 1947, that he had seen the spacecraft and the alien bodies that were allegedly taken to the base.

I should preface my statements by saying that I am fascinated by the UFO/Alien phenomenon in popular culture. As far as believing it, I will admit that in my younger days I was what Stan Lee would call a "true believer." I read many books on the UFO phenomenon; some were scientific and reputable, while others were the fantastic works of men in tinfoil helmets. As I have grown in age and knowledge, I have grown far more skeptical.

In conducting an investigation of this nature, considering the source of the info is very important. Let us take Walter Haut as an example. In July 1947, he was a lowly lieutenant in the public affairs office of the Roswell Army Air Field. On the day he issued the infamous "flying disc" press release, he went home and mowed the lawn. By all accounts, he wasn't visibly affected by the events that were transpiring. By the early 90's, as interest in the Roswell Incident expanded, Haut teamed with Roswell mortician Glenn Dennis and a third partner to open a tacky tourist-trap museum, the "International UFO Museum" along US 285 in Roswell.

In the past, Haut had never claimed to have seen an intact spaceship or aliens. Now, we have an all-too convenient affidavit, released just before the big UFO festival, where Haut allegedly spills the beans. Of course, he's dead now and can't be cross examined.

The shifting stories are an intriguing aspect of the Roswell phenomenon. Until the late 70's, people didn't talk about the Roswell Incident. Then the incident slowly trickled into the public consciousness, and witnesses began to come out of the woodwork. Many of the most prominent "witnesses" have changed their stories several times, with their accounts growing more detailed and sensational with each telling. Haut's business partner, Glenn Dennis, claimed that a nurse who was a friend of his gave him sketches of the aliens; then the military made her "disappear." Dennis later admitted that there was no nurse, only a fabrication. If the "flying saucer" theory ever contained an air of credibility, it was deflated with Dennis's admission.

It's important to remember the Roswell Incident in the context of the period during which it occurred. The "flying saucer" phenomenon did not begin until June 1947. The term "flying saucer" was coined by pilot Kenneth Arnold after a June 24, 1947 sighting. The Roswell Incident would unfold just two weeks later. Even the International UFO Museum admits that when rancher Mac Brazel first found the controversial wreckage, he didn't think much of it at first. It wasn't until he showed it to his neighbors, the Proctor family, that the Proctors would suggest the debris was extraterrestrial in origin. Brazel brought the wreckage to the town of Roswell ( a considerable drive from the ranch near Corona, NM) in order to collect a reward that was being offered for a flying saucer.

The best accounts of an incident are those taken just after the incident occurs. It minimizes any tendencies that witnesses have of embellishing or applying interpretations to the events they have observed. In this case, we have the interview with Mac Brazel by the Roswell Daily Record on July 9, 1947. The final segment is reproduced below:

Brazel said that he did not see it fall from the sky and did not see it before it was torn up, so he did not know the size or shape it might have been, but he thought it might have been about as large as a table top. The balloon which held it up, if that was how it worked, must have been about 12 feet long, he felt, measuring the distance by the size of the room in which he sat. The rubber was smoky gray in color and scattered over an area about 200 yards in diameter.

When the debris was gathered up the tinfoil, paper, tape, and sticks made a bundle about three feet long and 7 or 8 inches thick, while the rubber made a bundle about 18 or 20 inches long and about 8 inches thick. In all, he estimated, the entire lot would have weighed maybe five pounds.

There was no sign of any metal in the area which might have been used for an engine and no sign of any propellers of any kind, although at least one paper fin had been glued onto some of the tinfoil.

There were no words to be found anywhere on the instrument, although there were letters on some of the parts. Considerable scotch tape and some tape with flowers printed upon it had been used in the construction.

No strings or wire were to be found but there were some eyelets in the paper to indicate that some sort of attachment may have been used.

Brazel said that he had previously found two weather balloons on the ranch, but that what he found this time did not in any way resemble either of these.

"I am sure what I found was not any weather observation balloon," he said. "But if I find anything else besides a bomb they are going to have a hard time getting me to say anything about it."

Brazel had been in military "custody" after bringing the debris he found into the town of Roswell; he was likely briefed about what he had seen. Notice the carefully-parsed statement where Brazel describes a balloon, but claims it was not a "weather observation balloon." The Project Mogul balloon is a perfect fit with the description Brazel gave to the newspaper. What makes it so believable is that small details of Mogul, like the tape with flowers printed on it, would not have been available to the general public at the time. While Mogul was hardly a top-secret program with grave national security implications, it must be remembered that America was gripped with the early stages of Cold War paranoia at the time of the incident. Mogul's ties to the threat of Soviet nuclear tests made it all the more sensitive in the summer of 1947.

The Roswell Incident had grown far larger than the initial incident, and has come to mean different things to different people. For those lonely souls who want to believe that we have intergalactic neighbors in this universe, Roswell is the most tangible proof of that. For the paranoid and for those who view the military-industrial complex through cynical eyes, the conspiracy is far more important than alleged aliens. For a small town in the middle of New Mexico's scrub desert, aliens are a source of revenue for a town that has suffered four decades without the Air Force base that used to be a vital part of the local economy.