Chair Force Engineer

Saturday, June 30, 2007

There's Something About Santa Fe

I saw Santa Fe this past week, my first time doing so despite living in New Mexico for over two years. At this point, I don't see a compelling reason to go back, although I'd recommend that every visitor to New Mexico see it for a day.

The most maddening thing about Santa Fe is the way the city is laid out. Any attempts to drive through will be an utterly stupefying experience the first time around. Trying to drive through Santa Fe to Taos via US-285 is mind-numbing because of the maddening variety of stop lights that you will invariably catch; an interstate between Santa Fe and Taos would be ideal, in my opinion. Within the city, the streets are maddening. They meet at odd angles, many are one way streets over a certain section of the street, and many branch off at odd angles while retaining the name, or even stop and start again at disjointed locations. I guess I should cut Santa Fe some slack, as the city does date back to 1610, before modern city planning was in effect.

For a city that prides itself on being "liberal" and "tolerant," the Santa Fe motorists can be anything but. They'll pass you in no-passing zones and make angry and rude gestures at you when you're trying to navigate that most frustrating of cities.

Santa Fe is a good place if you're into art and culture; specifically, Hispanic and Native American cultures. The New Mexico Museum (a.k.a. The Palace of the Governors) was a very moving and inspiring experience. However, I had no desire to window-shop in elitist art shops all day, so I really couldn't appreciate the city for all it was worth.

There's a big difference between the philosophy of Albuquerque and Santa Fe, in my view. Albuquerque is a city that recognizes its past, but also tries to play a role in shaping the future. The housing hasn't totally conformed to the Pueblo Revival and Spanish Colonial styles like Santa Fe has. Albuquerque has brought in cutting-edge businesses; it was the place where the personal computer was born, and it is host to cutting-edge companies like Eclipse Aviation and Tesla Motors. Santa Fe, on the other hand, is a city that clings too tightly to its past. It enshrines its 400 years of history and uses them to lure in tourism, but it really isn't pushing the envelope into the future.

Sunday, June 24, 2007

Voices of Reason

Over the last year and a half, I've been kicking myself over the missed signs that could have prevented me from the terrible life choices that I have made. Up until now, I didn't think there were too many signs that could have steered me away from the Air Force in time to salvage my life.

Recently, I realized that there were two voices in the wilderness who spoke to me during my senior year in high school. The first of those voices was a friend of mine, who resembles "The Penguin" from Tim Burton's Batman Returns. He said to me, "You don't respect anybody, do you? How do you expect to be a military officer?" The other was my cross country coach, who pointed to my immaturity and inability to take things seriously. He also questioned my ability to be a military officer.

In hindsight, I didn't simply ignore these two voices of caution. I really did take their advice to heart. Unfortunately, I had other voices (with vested interests in the Air Force) who drowned out the voices of reason. Although I didn't realize it at the time, this was a case where it really pays to learn who to trust, and to discern which people really have your best interests in mind.

To the two people who tried to steer me straight, I can only offer my apologies for having discarded your advice. I will never question your judgement on these issues again.

Saturday, June 09, 2007

Missiles From Turkey, Iraq or the Sea?

I stand corrected in my post from yesterday in "Missiles From Azerbaijan?", having stated that Russia wants to use Azerbaijan instead of Europe as a missile defense site. Specifically, I should have said that the Russian proposal would substitute Azerbaijan for the Czech Republic as the site of the missile-defense radar. Within a day of the Azerbaijan announcement, Russian President Vladimir Putin proposed that the missiles to be placed in Poland could instead be moved to Turkey, Iraq or a sea-based platform.

The Russian tactic has shifted from opposing all missile-defenses to opposing their location in Europe. This indicates, in my mind, that Russia knows its nuclear deterrent is safe from a limited midcourse defense. Instead, Russia is trying to resist American influence spreading into former Warsaw-Pact nations. While the Cold War is over, Russia's mentality of preserving "buffer states" in central Europe is far from dead.

Basing missiles in Iraq is a non-starter for political and security reasons. After all, why guard against Iranian missile attacks by placing your interceptors within striking distance of Iran and its Mahdi Army proxies?

The Turkish option is worth considering on both political and technical grounds. It would be good for intercepting warheads aimed at Europe, although I'm not sure if it would be ideal for protecting the continental US. At the same time, the ill-will that many Turks feel towards the US military presence in their country will be a tough political hurdle. My guess is that it can be overcome if the US offers the Turks a lucrative foreign aide package. In the biggest of ironies, the US removed its Thor missiles from Turkey once the Soviets backed down from the Cuban Missile Crisis in 1962; now the Russians want American missiles (albeit defensive ones) back in Turkey.

A sea-based missile defense battery sounds oddly-familiar... Oh yes, we already have one of those: the Aegis Ballistic Missile Defense system. Over the last eight years, tests of this system from US Navy cruisers and destroyers have been almost consistently successful. The Aegis-based defenses have been the crown jewel in America's missile defense efforts.

I am personally mystified as to the difference in capabilities between the Aegis-based system and the Ground-based Missile Defense system that is generating so much controversy with the Russians. I would assume that the Aegis system is more limited, due to the need to fit it into a package that can be carried on a cruiser or destroyer. However, both systems bill themselves as "midcourse" defenses.

By this point, the obstacles to missile defense appear to be more political than technical. Midcourse interception of missile warheads will work, although further effort will be necessary to make the ground-based system reliable. The political question of basing the radars and interceptors stems from the technical question of where such sites should be optimally located to intercept missiles launched from North Korea or Iran. A rough simulation of this scenario is not difficult to create in Satellite Tool Kit; I may amuse myself by trying it out someday.

Thursday, June 07, 2007

Missiles of Azerbaijan?

In the ongoing debate between the US and Russia over missile defense, recent developments have brought an interesting technical twist to the problem. Russia has tried to create an alternative to European-based missile defense batteries by offering up the former Soviet nation of Azerbaijan instead.

The US position is that additional missile defense sites are necessary to defend the US and its European allies from future long-range missiles being developed by Iran (with much assistance from North Korea.) Based on my understanding of the Ground-based Midcourse Defense system, Europe would be a good location for a midcourse interception of a warhead headed towards Europe, or potentially the US. Azerbaijan is much closer to Iran, which actually makes it less suited towards midcourse interception of missile warheads. I tend to think that a missile defense site in Azerbaijan would be better suited towards boost-phase interception of ballistic missiles. However, a missile defense site in Azerbaijan might be a good location for a midcourse interception if Israel was the target of an Iranian missile attack.

This diplomatic overture will need to be thoroughly vetted by the missile defense experts before it's approved or rejected. Analyzing the situation will be very difficult, in light of the fact that the hypothesized long-range missiles we're guarding against have yet to be deployed by Iran. (It's reasonable to assume that Iran will field such missiles within the next decade, and preparing for that day will be a prudent course of action.) What trajectories would Iranian No-Dong-derived missiles take? What would the likely targets be? The solution to the Azerbaijan suitability question will require much assuming and plenty of war-gaming of the Iranian mullahs' mentality. The final missile-defense answer to the Iranian threat will be very expensive and will retain a high degree of flexibility.

Tuesday, June 05, 2007

DIRECT Delivery

In the current Direct Launcher scheme, the Ares V is replaced by a Jupiter 232 that falls short of Ares V performance. While Jupiter 120 outperforms the Ares I it was designed to replace, the performance gains are squandered if Jupiter 120 is only launching a 25 metric ton capsule instead of the 45 metric tons of payload it was designed to carry.

Part of that disparity can be fixed by shifting the lunar orbit insertion requirement from the LSAM to the Orion service module. It is a smart way to bring down the LSAM mass, move mass to the Jupiter 120 from the Jupiter 232, and perform the LOI burn in a cost-effective way. Still, this move falls far short of the 20 metric tons that will have to be moved from the Jupiter 232 to the Jupiter 120.

I've been trying to brainstorm ideas for correcting this mass disparity in the Direct Launcher proposal. One idea is propellant transfer, although NASA will certainly reject this (at least for the initial lunar missions.) However, two other ideas I've been considering might make DIRECT technically possible, within NASA's current EOR-LOR paradigm.

NASA's current thinking on their Lunar Surface Access Module is that the crewed portion should be split into two portions. There would be a relatively-spacious habitat module that would be left on the lunar surface, with the aim of building a base consisting of several LSAMs. These LSAM's would also have a puny "ascent cabin," a pressurized vessel that can lift four astronauts from the lunar surface to their Orion capsule in low lunar orbit.

The concept of splitting the LSAM cabin gave me an idea for saving the DIRECT proposal. What if the LSAM ascent cabin was launched on the Jupiter 120, mounted in the spacecraft adaptor just below Orion? A Jupiter 120 would launch the ascent cabin and Orion directly into a 120 x 120 nautical mile orbit, instead of the baseline 30 x 120 nautical mile orbit which requires a burn of the Orion service module engine (designed so the Jupiter core will burn up on reentry instead of becoming a piece of orbiting space junk.) On orbit, Orion would dock with the nearby ascent cabin, then perform another series of burns to rendezvous with the LSAM descent stage and its mated Earth Departure Stage. The problem I see with this approach is designing a reliable system that will mate the ascent and descent portions of the LSAM, but will still release properly when it comes time to leave the lunar surface by launching the ascent cabin.

A second option I thought of was to switch the packaging of the Orion and LSAM in the DIRECT proposal. In this version I've dreamed up, the first launch will be a cargo Jupiter 120 carrying just the LSAM. The second launch will be a manned Jupiter 232 with the Earth Departure Stage mated to the Orion spacecraft. Upon Orion's successful launch, the LSAM, not Orion, will fire its engines to rendezvous with Orion and the attached EDS. During the rendezvous, LSAM will be controlled remotely from mission control in Houston. The reasoning behind making the LSAM take the active role in the rendezvous is that LSAM has highly-throttleable engines that can perform the precise burns required for rendezvous. Trying to perform the rendezvous with the Orion-EDS stack would be too unwieldy, due to the heavy EDS and the nature of the J-2X engine(s) that would be required to perform the rendezvous burns (plus the reaction jets on Orion that aren't designed to control the Orion-EDS stack.)

Of all the packaging options I've thought of, I like the final idea of launching LSAM on a Jupiter 120 the best. The reason is that NASA's baseline LSAM mass of ~43 metric tons (a figure that I believe can be reduced, but one I will use for the time being) is a nearly-perfect fit for the Jupiter 120's claimed ability to insert ~45 metric tons into the assembly orbit. Further, if Orion's mass can be brought below 18 metric tons (something that might be possible if the capsule diameter shrank below 4.5 meters,) it could mean more propellant mass in the EDS.

Direct Launcher can work if it's given a chance, but it will need some original thinking about how to package the elements of the Orion-LSAM-EDS stack onto two launchers. It will also require NASA to modify its concept of EOR-LOR that was established two years ago in the ESAS study.

Hopefully this post has been some entertaining food-for-thought. Upcoming posts will cover the topics of NASA's newly-adopted "clean pad" philosophy, optimizing the size and mass of Orion for the lunar & ISS missions, and why "spiral development" will be necessary to achieve the Vision for Space Exploration.

Sunday, June 03, 2007

A Business Case For Falcon 9?

The way to make a small fortune in space launch is to start out with a large fortune.
--Elon Musk

The founder of SpaceX, Elon Musk, is very familiar with the chances for financial success in the field of space launch. With that being said, it should be noted that Mr. Musk is a true believer in the cause of spaceflight and in making mankind into a spacefaring civilization. If he believed that he'd get rich off the effort, he'd be deluding himself.

Nevertheless, I'm still a bit confused as to why he'd want to compete his Falcon 9 against EELV's like Atlas V and Delta IV. It would appear that, with a government-sanctioned, government-subsidized monopoly in this class of launchers, there's no substantial market that could justify the development of yet-another EELV.

It was suggested to me that SpaceX could make inroads into the EELV market if they could deliver a significantly-cheaper rocket. Certainly this will be possible if SpaceX can keep their company small and their management lean. SpaceX knows that the market can't justify the production of 15 EELV's per year, so they probably won't build a Falcon 9 plant that's anywhere near as big as the Decatur, AL plant owned by United Launch Alliance. SpaceX is currently a lean company with lean management, but that may change as SpaceX gets closer to launching a successful orbital mission. If you want to do business with the government, you've got to play by their rules. And that probably means you'll need scores more employees to cut through the bureaucracy.

In terms of engineering their rocket, I think SpaceX could achieve cost savings over Atlas V and Delta IV. The tankage on both stages is similar. The propellants used by both stages are the same (the alleged cost savings of this design choice led to the hydrogen-fueled first stage on the Delta IV.) There's only one engine design used, and the first stage uses a cluster of these smaller, cheaper engines instead of one large, expensive engine.

I'm making a big assumption by believing that nine Merlins are cheaper than one RS-68 or RD-180. After all, RD-180 is built in Russia where labor rates are much lower than in the US. But I also believe that Merlin costs will drop dramatically as a result of bulk production. Even the smallest Falcon 9 needs ten Merlins in order to achieve orbit (nine on stage 1 and one on stage 2.) Even if only four Falcon 9's are launched in a given year, it represents forty Merlin engines being produced. Can you imagine Pratt & Whitney-Rocketdyne producing forty engines, let alone engines of the same type, during the course of a year? Certainly not in today's market for space launch.

Ultimately, the economic success or failure of Falcon 9 hinges on the Dragon capsule. If SpaceX can grow the EELV market with flights to the ISS, flights to a Bigelow space station, and even free-flying space tourist flights, they may be able to launch enough rockets per year to turn a profit. Without manned spaceflight, I think the market for Falcon 9 looks pretty dim.