Chair Force Engineer

Saturday, March 31, 2007

Why Space Acquisition is Broken

This post promises to be perhaps the most controversial one I've ever made, and it may land me in deep doo-doo. Yet I think the message is so important that it must be said, one way or another.

The full question of why space acquisition is broken is a complex one that can't be summed up merely with the observations of a junior officer. It can't be answered in a short blog posting, either. Yet progress has been made by the mere fact that the Air Force has actually admitted they have a problem here. Then again, problems as big as the SBIRS program are impossible to hide forever.

I think that much of the space acquisition problem lies in an unrealistic belief that space programs can be done quickly and cheaply. Nothing can be further from the truth. Space efforts will always be more challenging than equivalent airborne systems due to the challenges created by the space environment. The key is to employ space systems only in areas where the unique benefits of operating in the space environment can be used to enhance the military's capabilities.

The fact that we live in a pilot-dominated Air Force certainly bodes poorly for the space community. Few in the Air Force question why it took 15 years for the F-22 to progress from prototype stage to Initial Operational Capability, or why each example costs hundreds of millions of dollars, or why the Air Force is cutting 40,000 members of its workforce in order to afford this Cold War relic of a fighter. A space asset with similar development and acquisition challenges as the F-22 would not be given the same amount of leeway.

Most importantly, based on my experiences, our space acquisition efforts have been hampered by politically-driven budgets and schedules that have zero basis in reality. I don't know exactly who sets these unrealistic cost and schedule targets, but the people who are experienced in building and operating space systems know these budgets and schedules are totally bunk.

Cynically, it would seem that the Air Force tells Congress that its space programs will be quick and cheap, so the Congress will release enough money for the Air Force to get its foot in the door and start the program. After the program gains momentum, the Air Force will ask Congress for more money to finish the project. Congress will usually relent, at least a certain number of times, because they don't want to be seen as squashing a militarily-relevant program. Sometimes this cycle is by accident (underestimating the complexity of the program,) and other times it's by design (because Congress would never give its initial approval if they knew what the real cost and schedule would turn out to be.)

The most adverse effect of unrealistic, politically-driven schedules is that contractors will do rush jobs and cut corners with the design in order to meet these cost and schedule targets. I can't blame the contractors one bit; after all, you can't make a chicken salad if you're only given chicken shit to work with. And when the government takes delivery of these unfinished space systems, it faces an important choice: fly it as-is (and risk your satellite turning into an orbiting brick,) or pay the contractor more money and give them more time to fix it. Most people will recognize that it's faster to do things correctly on the first try, rather than messing them up and having to fix them later.

A lot of clear thinking is necessary to solve the space acquisition dilemma. I believe that lower expectations for space aquisition are the first order of business. Next, the Air Force should commit to realistic budgets and schedules that reflect the engineering realities that the integrators and operators will face. Lastly, we need a broad re-think of the role that space plays in the way that the United States wages war. Space assets are inherently expensive, and thay should be employed only when the space environment's unique properties can be employed to great effect on the battlefield. There are plenty of applications where space assets could probably be replaced by unmanned aerial vehicles and lighter-than-air craft. Unless the Air Force takes a critical look at the ways it currently employs its space assets and its future projections, the ossified space paradigm of the present will never be shattered.

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Tuesday, March 20, 2007

Comeback Kids

Watching the Falcon I launch makes me very proud of the SpaceX team. The two aborts that were so disappointing to watch were at least a validation of the robustness that was built into the rocket when it was redesigned over the past year.

At this point I've lost video feed and I'm anxiously awaiting word on what the mission's status is. I noticed the less-than-nominal staging event and I noticed the second stage engine gyrating a bit too wildly for my tastes before the video cut out.

Before the launch, my prediction was that stage 1 would work as planned, but there would be a problem between stage separation and orbital insertion. I don't take any pride in the fact that my educated guess is probably the case today. Then again, I promised my coworkers that I'd buy them beers if SpaceX actually achieved orbit.

Regardless of whether this Falcon I shot successfully achieved orbit, the SpaceX team should be proud of how far they've come, and confident that the next launch will be a success.

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Wednesday, March 14, 2007

Delayed Response

There are a lot of people in the Pentagon and Congress who are excited about the concept of “Operationally Responsive Space.” There’s a lot of misunderstanding about what this new cliché encompasses, but my understanding of the subject is something like this: it begins with a warfighter on the ground who needs a space asset to perform his mission. Within a short period of time (we’re talking days, not months,) a satellite can be pulled from storage and launched in support of ongoing combat operations.

I have some very strong feelings on the subject. Perhaps my strongest assertion is that ORS will never be achieved unless the Air Force as a whole streamlines its bureaucracy in the name of responsive space. How can you have responsive space access when dealing with the mountains of paperwork that are required just to get somebody to provide you with a mission control facility, or if it takes four months to award a contract for an essential spacecraft component? I think the AF is counting on going through “business as usual” to create a stockpile of responsive-space satellites which will then be launched on demand. But from a developmental standpoint, the “business as usual” approach will continue to delay important R&D programs that are necessary for validating responsive space concepts.

Another long pole in the tent is the launcher that will provide responsive access to space. As it stands, the closest thing we have to a responsive launch vehicle is a Minotaur I. We still have a long way to go before responsive launch is within reach. The problem is that we keep on thinking that a “responsive space launcher” should work like a traditional launch vehicle, when it should work like an ICBM. Think about it for a second: these ICBM’s sat in their silos on the alert for years, ready to nuke the Commies if the cold war ever went hot. We still need a launcher that can sit in storage for years and launch at a moment’s notice. The silo concept is still applicable, because it makes integrating the payload with the rocket a bit easier (since the payload need never be raised above the ground level, while the rocket is already inside the silo.)

Some have suggested that Michael Griffin should sell out to ORS in order to get his beloved Stick (Ares I) funded. That’s not such a bad idea. The Shuttle SRB, and its 5-segment derivative, are worthy of consideration as ORS launchers. They would require a solid (or storable liquid) upper stage, instead of the cryogenic liquid one proposed for Ares I. They’d likely be oversized for the mission, but perhaps ATK could figure out a way of cutting an SRB down to 2 or 3 segments for an ORS booster. As long as he can find a way to marry Ares I with the responsive space launch concept, there’s a chance that Michael Griffin can solve the Ares I funding shortfalls.

Monday, March 12, 2007


For an agency that's trying to create "Apollo on Steroids," NASA seems to be forgetting how it was done in the first place. Many key decisions are being made in a way that runs totally opposite to how Apollo was run.

Mark Wade is fond of pointing out that in Project Apollo, the Apollo CSM spacecraft and Saturn V launch vehicle had their designs frozen well before NASA had settled on a mission mode. The contracts for the Saturn V's stages and the Apollo CSM were awarded in summer 1961; it would be another year before the landing mode debate was settled, and it wasn't until December 1962 that Grumman was awarded the Lunar Module contract.

Fast forward to 2005, when Michael Griffin tosses all of Sean O'Keefe's lunar studies out the window and sets up ESAS to come up with the mission architecture. The team agrees on EOR + LOR and assumes a crew of four on the moon for seven days. The debate over mission modes, mission duration, and crew size is kept within the ESAS group and not opened up to the entirety of NASA like it was in 1961-2.

Since that fateful decision, NASA has made many changes to its proposed launchers just to keep up with the spacecraft, instead of desiging the spacecraft to meet the launcher. In Apollo, the choice was between LOR using a single Saturn V, EOR using two Saturn V's, or direct landing a two-man capsule on the moon with one Saturn V. Fast forward to today. Aside from the shrinking of Orion to 5m diameter, all of the changes have been made to the launchers.

In another sense, NASA's being run totally backwards from the way it was in the 1960's. The grand old NASA administrator, James Webb, was not very knowledgeable about space vehicles, but he was very politically savvy. Michael Griffin is a genius engineer but lacks political savvy. Of those two qualities, it's the latter that's needed in an administrator. The administrator has plenty of smart engineers at his disposal. If he lacks political agility, though, Congress will deny him the bucks that make "Buck Rogers" possible.

Saturday, March 10, 2007

Folded Wings & Propaganda Peddlers

The Islamic State in Iraq claims that it will soon release a video regarding the death of Major Troy Gilbert, an F-16 pilot who perished in November 2006 while strafing enemy forces in Fallujah, Iraq. This would be the second video regarding the incident, as one was released by the Iraqis shortly after the crash occurred.

When I fist started reading about the incident, things didn’t add up in my mind. The Air Force did not make a declaration of death until performing DNA tests on remains found at the site of the crash. However, there were media reports that the first video ‘showed graphic images of the dead pilot’s body.’ This raised the possibility that Maj Gilbert had attempted to eject, and that the Iraqis had brutalized and desecrated his remains.

I wanted to investigate further, so I found the original video on the internet. Clearly identifiable pieces of aircraft wreckage are shown, including the aircraft’s vertical stabilizer and canopy (the forward canopy glass & frame assembly, which is blown free during an F-16 ejection.) The last shot purports to show the pilot, but I had a big problem with it: it looks too fake. The parachute is deployed and mangled, and the “pilot” has no visible arms or legs. No blood is discernable in the video.

Hopefully the Air Force accident investigation will find good answers to all of the questions posed by this disturbing incident. My theory, based on the video and the Air Force press releases (which I frankly shouldn’t trust anymore, based on personal experience) is that Major Gilbert’s aircraft struck the ground while strafing the enemy at low altitude with his 20mm cannon. The aircraft may have been hit with a lucky shot by small arms, which disabled the aircraft in some way. Major Gilbert probably made an attempt to escape at the last moment, or the canopy pyrotechnics may have fired when the aircraft impacted. I don’t believe that the Iraqis found any discernable human remains, so they faked a body for propaganda purposes. We live in a world where a militant group's propagandist can be referred to as an "Iraqi journalist” by Associated Press, and we should not be surprised with the contents of the video.

By investigating the incident, we will hopefully find better tactics for protecting our pilots, and possibly dish out some payback against these Iraqi assholes who would have committed an unspeakable act like desecrating a body. Above all, the investigation should bring some peace to Major Gilbert’s family and friends. Godspeed to a great airman who was respected by all who knew him.

Friday, March 09, 2007

TeamVision (Part 5 of 5)

In Era 5, TeamVision lays out the opening steps for opening the solar system to human spaceflight. It doesn’t begin with a Mars landing, but the asteroids and the Martian moons are targets for precursor missions that will lead to Mars.

One thing I noticed in the proposal is an Orion configuration which places a habitat module between the Command Module and Service Module. My guess is that, like in Manned Orbiting Laboratory, the astronauts will transfer between the CM and habitat by way of a hatch in the heat shield. While this may seem like a vulnerability during re-entry, the reflight of the Gemini 2 capsule demonstrated that the hatch would fuse closed during the plunge to earth.

Artificial gravity is provided for the astronauts on their trip to the vicinity of Mars. While NASA continues research into the effects of weightlessness on the human body, it’s clear from what we do know that weightlessness is generally a bad thing over long periods of time. While Robert Zubrin and others have suggested spinning the spacecraft (tethered to the booster) at a rate that would provide the 0.38g of the Mars environment, TeamVision recommends a higher level of artificial gravity due to the stresses created by EVA’s in bulky space suits. The higher level of artificial gravity creates more demands on the spacecraft and tether system. There’s debate on whether a tether is reliable enough to use in this application without snapping, or if a heavier truss would be better. I think that if shape-memory composites can be successfully demonstrated, they’d be an ideal candidate for the truss. In any event, artificial gravity should be tested in low earth orbit before it makes the flight to Mars.

The Mars expedition would be launched using two launches of the Jupiter III, plus lunar LOX that would be transferred to the spacecraft at EML1. The first launch would be an unmanned cargo lander. The second would be a manned spacecraft, which would occur roughly two years later.

The cargo lander would reach Mars by way of a flyby trajectory that took it past Venus. I wonder if TeamVision accounted for the extreme thermal shifting that will occur between the Venus vicinity and Mars vicinity. The thought of performing a Venus flyby was enough to frighten Robert Zubrin.

In any event, the cargo lander would deliver a Mars Ascent Vehicle (MAV,) supplies, and a pressurized rover to the red planet. It would utilize Martian carbon dioxide in a Sabatier reactor to produce methane propellant for the ascent to Mars orbit once the surface mission is complete.

The manned crew follows a faster, fuel-intensive trajectory which requires 180 days to reach Mars. Separate in-space & surface habitats will be their housing (based on the lunar habitat, but optimized for the unique environments they’ll be exposed to.) The surface habitat will use an optimal combination of propulsion and parachutes to make a soft landing with a human crew. No discussion is made about crew visibility during descent, but the idea used for the “direct ascent” moon lander should apply. The crew will spend 619 days on Mars before climbing in the MAV and docking with the space habitat and its attached propulsion stage. Artificial gravity is provided on the outbound leg of the journey. I was a bit concerned that no discussion was made about how the return capsule will deal with the speed of a re-entry at earth from the speeds necessitated by the trajectory from Mars.

I also get a bit uneasy when hearing about a reliance on aerobraking for capturing into Mars orbit. Mission planners count on saving a lot of propellant mass by braking with atmospheric friction. But aerobraking has never been used for a purely non-propulsive capture into orbit around a planet before. I’d like to see it tested before we proceed down that route. Then again, I’d shudder to think of how big these Mars ships would be if aerobraking weren’t used. As TeamVision admits, “Understanding the degree to which aerobraking can be utilized will be a driving Mars mission parameter.”

TeamVision even gives attention to the "and beyond" part of NASA's “Moon, Mars and beyond” mantra. Proposed missions for Era 6 include building a “Monty Burns Sun-Shield” to counteract Global Warming, the mining of Lunar Helium-3 (an unlikely prospect in the near term,) and asteroid protection.

In Era 5, TeamVision lays out a good architecture for a chemically-propelled trip to Mars and back. Some of the Mars Direct ideas, like artificial gravity and in-situ resource utilization, are implemented. It begs the question of whether the Sun-Mars L1 point should be used as a waystation in the same way that Earth-Moon L1 is a waystation for flights to the moon and back.

That being said, I think the lack of nuclear propulsion is a real drawback to the exploration of Mars. While the TeamVision Era 5 proposal gets us to Mars with chemicals, it’s like sailing the ocean with sailboats, when steam-powered ships are being held back only by the political whims of the people back home. Nuclear propulsion greatly reduces the mass that must be launched to Mars, although it will not benefit from the production of lunar LOX. Development of nuclear-thermal and nuclear-electric rockets will force us to invest a lot of money and political capital, but the payoff is too enticing to refuse.

As an overall, integrated plan, I truly appreciate TeamVision's effort to get the vision back on track. TeamVision has a clear path for exploring both the moon and Mars, whereas NASA hasn't publicly discussed what comes after we land on the moon. TeamVision also has a cost-effective way to develop lunar-specific hardware in a shorter period of time than NASA does. (By adopting direct landing & ascent, and developing Jupiter I instead of Ares I, TeamVision gets a foot in the lunar doorway before the next administration rolls into Washington.) Perhaps the most enduring contribution of the TeamVision report is a rational discussion of the lunar crew size and the strong argument that NASA's current crew size is twice what it needs to be.

The implications of a smaller crew are huge. If the two astronauts ride in a Gemini-sized capsule, they can make a direct landing & ascent with a Saturn V-class booster. The smaller capsule could also make the "Direct Launcher" concept work, by reducing the mass that must be put in low earth orbit (due to the lower-than-anticipated Isp of the RS-68 Regen engines.) Finally, it could enable an all-EELV (a.k.a. "Less Pork") approach, akin to the "Early Lunar Access" proposal of 1992.

Stephen Metschan, who wrote the TeamVision report, referred to it as a "Voice in the Wilderness" akin to John Houbolt's advocacy of Lunar Orbit Rendezvous. While today's NASA will probably be undone by its closed-mindedness, TeamVision's voice in the wilderness is saying a lot of inspiring things to the future generations who will succeed in exploring the solar system.

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Wednesday, March 07, 2007

Grounded for Life

NASA finally made the expulsion of Lisa Nowak official, by ending her temporary duty with the agency and sending her back to the US Navy. Time will tell if the Navy takes any kind action against her in the military justice system.

At the same time, her former partner in the astro-love-triangle, Bill Oefelein, appears to be getting off without punishment. This is a dirty shame, as it appears that Oefelein and Nowak had an adulterous relationship that probably ended their respective marriages.

As best I can tell, military astronauts on temporary duty with NASA are still subject to the Uniform Code of Military Justice. That means they can be court-martialed for adultery. While adultery prosecutions are rare (and are usually pursued only after a 'no-contact' order from a commander,) I have little tolerance for it, and it gives NASA and the Navy a legal avenue to wipe off the scourge of those two space-cadets.

If a person betrays the spouse that he/she has pledged his/her life to, what does it say about the cheater's character? I wouldn't trust the assclown with a space shuttle, that's for certain.

Some may say that NASA is employing a double-standard here, although Lisa Nowak clearly crossed a line with her bizarre (and potentially murderous) assault on the Captain who entered the sordid soap-opera. But I will say that NASA has grounded astronauts for far more trivial things than the current scandal (Deke Slayton's "heart murmur," the Apollo 7 "rebellion," and the Apollo 15 postage stamp scandal, for instance.) With so many rookie astronauts chomping at the bit for a flight on the shuttle or Orion, there's no way that a numb-nut like Bill Oefelein should be allowed to fly in space again.

Monday, March 05, 2007

Space Station Tedium

I promise that I will post the last chapter on TeamVision this week. But Dwayne Day's article Death Throes and Grand Delusions in The Space Review really caught my interest.

As a grammar school student in the late 80's and early 90's, I remember my Weekly Reader saying that Space Station Freedom was going to cure cancer and lead to all sorts of neat breakthroughs on the bleeding edge of science. That vision was the future we wanted to believe in.

The future that we actually got was the International Space Station, which is much more complex than good ol' Mir, but seems like it isn't much of an advancement as far as science is concerned. It takes a cosmonaut with the credentials of Pavel Vinogradov to blow the lid off our space station fantasies:
...We are now flying with zero efficiency. We’re carrying out 30-year-old experiments. Even if they are very important, do they move us forward? I have no idea. The Americans are doing experiments that we did back in the Salyut and Mir days. Why? Can’t they find the results [in Russia]? Or don’t they want to? This is amazing. I always thought we have to fly in the interests of science, to produce results needed by many people, and all we’re doing is keeping the station in working order. 62% of our time goes to servicing on-board systems, 15% to personal needs and only 23% to science…

This is an amazing revelation. So we're paying $7B per year and putting the lives of our astronauts in jeopardy just so we can rehash Russia's accomplishments on Mir? Absolutely ridiculous!

As far as Dr. Day's central argument (the decay of the once-great Energia company) goes, it's hard to not see the Russian manned space program in its dying convulsions, a victim of a poor grasp for capitalism. Energia should have seized upon the demand for space tourism and began launching Soyuz missions explicitly for tourist purposes. The company could have even built a duplicate of the Mir core module to give the tourists a destination where they could play. While the startup costs of such a project would be startling, there are plenty of American mega-millionaires (Dennis Tito, Anousheh Ansari, etc) who have a demonstrated willingness to pay the high prices involved. Perhaps if commercial money was supporting a space station like the Mir clone I propose, there might be actual research into life-saving drugs going on aboard that station.

Energia had a good idea regarding the Kliper spacecraft (at least until it sprouted wings and landing gear,) but it was blocked by the extreme conservatism of Roscosmos. Energia will probably be doomed by the delusional visions of the Putin-crony who was recently put in charge of the company.

We face a future where we have a space station that could never survive as a commercial venture, but it's being propped up by the govenments of the spacefaring nations. SpaceX or RpK may build an ISS-compatible capsule and fly it in the 2010-2012 timeframe. NASA is still working on Orion, which will meet all of the ISS needs, but it may not be ready until 2015 or later. For Energia and the Russian manned spaceflight program, they will need to make bold but calculated moves to avoid being left in the dust. By luring in European government dollars and relying on the tried and true Zenit rocket (although last month's SeaLaunch failure should give us pause,) the Russians could design a reusable, six-man semi-ballistic capsule. That evolutionary step beyond the 40-year-old Soyuz is perhaps the only thing that can jump-start a stagnant space program that used to be the most elite space program in the world.

Friday, March 02, 2007

TeamVision (Part 4 of 5)

Perhaps I was a bit premature in condemning TeamVision during Era 3 of their plan for lunar and Mars exploration. I criticized them for relying on direct landing and ascent on the moon instead of an EML1 rendezvous. By the time I got into their Era 4, creation of a lunar infrastructure, they turn into voiciferous advocates of an L1 infrastructure.

The thrust of TeamVision's Era 4 is that the moon will be utilized to produce liquid oxygen. This propellant is delivered to a transportation node at the Earth-Moon Lagrange point. Orion CSM's will be launched on Jupiter rockets to dock with the EML1 propellant depot. The astronauts will transfer to reusable, Mars-class landers that are fueled by lunar liquid oxygen. Further, the EML1 depot will serve as an assembly point of a future Mars spacecraft, assembled out of modified Orion CSM's, already-developed habitat modules, and 10m rocket stages developed for the Jupiter II.

The report really doesn't address how the reusable landers will be refueled with methane, but this will presumably be delivered to the EML1 depot from earth. The station will also need to be refueled with propellants to maintain its station at EML1 from time-to-time. All of this requires a lot of mass to be boosted from earth. Era 4 relies on yet another new rocket, the Jupiter III, to deliver between 200 and 500 mT of cargo to low earth orbit.

While Jupiter III is the lynchpin of TeamVision's Era 4 architecture, I feel that it's too complex to proceed in its present form. The rocket's core is based on the shuttle ET, with J-2X engines mounted underneath. This core is flanked by two standard shuttle ET's, each one with two standard shuttle SRB's. What engines do these ET's feed? Why, there's a cluster of "RS-100" engines (apparently a scaled-up RS-68) mounted underneath the J-2X's in an expendable pod! The rocket apparently begins its ascent by igniting the RS-100's with propellants in the two laterally-mounted ET's. Then the SRB's ignite and the rocket lifts off. The SRB's are the first to burn out and are cast off. Then the ET's are depleted, so they are cast off, along with the RS-100 pod. Then the J-2X's ignite on the core. Once the core burns out, an upper stage with two J-2X engines ignites to push the payload into orbit.

Jupiter III seems like a horrendously complex way of launching what would otherwise be a very wise goal, the buildup of an L1 transit node. There's a lot of complex plumbing connecting the two ET's to the engine pod, and the thrust from the four SRB's, mounted far off the vehicle's centerline, has to be carefully balanced. My preferred concept would use a two-stage, 10m core which burned oxygen and hydrogen propellants. The first stage would be flanked by several kerosene-fueled booster modules. The number of kerosene boosters would be varied based on the mission requirements.

Overall, what's my opinion of the Era 4 plan? It's mixed. The L1 infrastructure is genius, even if it's used for the moon only (not as a starting point for a Mars mission.) Jupiter III looks more like mad science than genius.

Thursday, March 01, 2007

Team Vision (Part 3 of 5)

Era 3 of the TeamVision proposal finally lands humans on the moon. This is where the underlying assumptions of TeamVision start to get shaky.

Previously, TeamVision called for the development of the shuttle-derived Jupiter I booster to enable robotic lunar rovers and human missions to lunar orbit. The firm calls for the development of a "Jupiter II" booster for the human lunar landing missions in Era 3. The problem I see is that Jupiter II has very little in common with Jupiter I. The 5m Integrated Common Evolved Stage now becomes a 10m rocket stage for the Jupiter II. The new rocket requires the development of 5-segment solid rocket boosters and three new, liquid-fueled stages: one powered by five RS-68's, one powered by two J-2X's, and one powered by an RL-60.

So TeamVision is proposing a new launch pad and umbilical tower, new tankage, new SRB's, and development of two engines (J-2X and RL-60) that only exist on paper, as far as I can discern. The fact that three stages (plus the SRB's) are needed to reach low earth orbit is a bit too complex for my tastes; I feel that three stages in total is an optimum balance between performance and complexity. Also worth noting is that the separation plane between the first and second stages is also the same place where the carry-through beam connects the forward attach points of the two SRB's.

To their credit, TeamVision has come up with a launch vehicle that can put 178 mT into low earth orbit. Why build a rocket even more powerful than the Ares V design? Because TeamVision believes that the Block III Orion CSM should make a direct landing and ascent on the moon. The direct approach is heavier than lunar orbit rendezvous. I also believe that it sacrifices the potential for reusability in the future. The reason is because the Orion CSM will need a "lunar crasher stage" in order to de-orbit and provide propulsion for most of the descent phase. In the TeamVision plan, the lunar crasher is based on Jupiter I's 5m upper stage, but with an RL-60 main engine. The stage is then discarded just prior to landing, in order to keep the lander at a reasonable height (otherwise, imagine a pilot trying to land an Atlas missile, partially loaded with propellant, directly on its tail.) This is one of the reasons why I support a rendezvous at the earth-moon L1 point instead of direct landing and ascent.

There are some good features of TeamVision's Era 3 proposal. The most compelling argument for direct landing and ascent is that a separate lunar lander doesn't need to be developed. The problem of having a pilot steer the capsule to a landing is solved by having the pilot stand vertically in the command module, staring out through a viewing dome installed in place of the docking module. Finally, TeamVision believes that NASA's proposed crew size is too big; all of the science objectives can be accomplished by a crew of two (plus robot rovers) working for seven days on the lunar surface. This begs the question of "If we only need a crew of two, why do we have to make the Orion command module bigger than the Apollo command module?" I think that NASA has a responsibility to give taxpayers a good and coherent answer to this stumper.

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