Sunday, October 26, 2014

Launch Reimagined

In my opinion, there is a fundamental flaw in our efforts to commercialize launch operations to space.  We had scientists show us how to do it under NASA and then had companies do it for a profit.  OK.  That sounds all nice and good.  Except we end up with an enormous launch cost per payload weight measure.  Now, scientists take into account to most efficient way to do things.  They did a good job of this in getting to space.  They developed a very efficient way, scientifically.  Sometimes scientific efficiency opposes financial realities.  I was shocked when my physics teacher, back in high school, said that to travel from point A to point B in a vehicle and to have that vehicle at point B at the end of the trip was not very efficient.  Of course in my mind, I thought I still needed that vehicle to go other places, and that's where economics came in.  So why do we throw away rockets?  We do it for efficiency, not economy.  Maybe we should alter the way we go to space to make it more economical.  SpaceX has an idea, DARPA has and idea, and I have an idea of how to make change this efficient operation into and economical one.

SpaceX, as most people know, wants to make throw away rockets into reusable rockets.  That's tall order.  So tall, that they are the only ones actively pursuing this avenue.  They have succeeded in reentering their first stage Falcon 9 v1.1 and flown it all the way down to the ocean.  Now there is talk of them wanting to land their first stages on a floating platform.  Kudos to them for getting this far.  They are ahead of everyone else.

DARPA came up with an idea that uses wings.  It's called the XS-1.  The idea is to have an unmanned space plane act as the first stage of a rocket to launch small satellites.  Supposedly, these would fly back to base.  That would be good.  You want your first stage to come back to base to reuse it and not haul it back to base.

Here's my idea, as crazy as it sounds.  Scientists, scream if you must.  In a 2 stage rocket, make the first stage suborbital.  Yes, you heard me.  Let it only go up and down, like an elevator.  Let the second stage be responsible for the lateral velocity.  Mull that over a bit.  Sure, how high should that first stage go?  Pretty high, I can imagine.  Perhaps even beyond the atmosphere (greater than 100 km in altitude).  How mush fuel should that second stage have to get from 0 to 17,000 mph before falling back to Earth or sustaining altitude while accelerating laterally?  How much fuel would the first stage need for all the fuel the second stage would need and to land as well?  A lot.  OK.  What are the benefits?  How about having a first stage that can land on the same landing pad as it launched from.  Conceivably,  it could be prepped with another second stage, payload, and fuel and fly in short order again.  Now we're talking rapid turn around for a first stage rocket.  What is that worth?

 So there they are.  SpaceX has it's plan to alter the launch operations to make it more economical and is working it.  DARPA has a competition with an idea using wings.  I just throw science to the wind and take an idea that leverages most fuel possible to get the most out of the hardware.  What is sure is that launch as we have seen it in the past is not how it's going to be in the future because we just can't afford it anymore.

Wednesday, October 15, 2014

Boeing CST-100

Credit NASA
Boeing and SpaceX have won NASA's Commercial Crew Transportation Capability competition in the last month.  Good job to both teams.  Now, I've written a lot about SpaceX because there has been a lot to write about.  Here, I'm gong to change my focus on the Boeing team.  It may come to a surprise to some of my readers that, in fact, I like Boeing as a company.  I've been a customer, both for pleasure and business, for many years of their jetliners and never had a complaint.  Boeing is mostly a mainstay company.  They have their jets for many decades.  Sure, they change them to meet market demands, but for the most part, they keep them up and running for as long as possible to keep costs down both for themselves and for their customers.  On the rocket side, they have the Delta family.  It has been operating well for many years.  There has been a couple of mishaps, but overall everything is OK.  They do make the currently largest rocket in the world, the Delta IV Heavy.  Then they have business with the military and NASA in miscellaneous projects - at least for this post.  CST-100 is a different project for Boeing.  For a company that is a safe company as Boeing, CST-100 is really out there.

The first thing about CST-100 is that it is not business as usual.  It is not a 'cost plus' contract.  It is a contract where risk is taken on by Boeing.  That, I sense, is a big deal to the company.  Sure, they do take on that sort of risk when they sell a jetliner to an airline company, or do they?  Well there is no airliner to go between the end user and the company.  So far, the contract will be just between NASA and Boeing.  In the unforeseen event Boeing decides to put in a third party, like ULA, then the dynamic would change a little.  Let's assume that it won't.  Boeing will take responsibility for the craft and all the technicalities.  That means that they retain ownership.  For a disposable craft, ownership is a short lived thing.  Risk is the important item here.  Any technical malfunction leading to human injury or fatality could lead to money lost by the company.  Amount will vary on a case by case basis.  Of course, since this is rocket industry, the sky is the limit.  (These are generalized statements. I have no clue what agreements NASA and Boeing will have including anything pertaining to risk.)

Credit EC Holm
Now, in face of the higher risk, I can see why the CST-100 was designed the way it was; it has little innovation.  About the only two major innovations it does have are that it can land on land using airbags and has autonomous docking.  Otherwise, it is shaped like the old Apollo capsule, most of its supporting systems are in the service module like in Apollo, thrusters are in the service module like Apollo.  So the craft has a strong design basis in legacy systems.  I believe this was to reduce risk.

There seems to be a belief out there on the net that this craft's electrical system is only powered by batteries alone.  If that is the case, it is unprecedented and could possibly be a significant innovation.  Batteries are traditionally heavy and don't last long.  They are usually replenished with power form solar cells or fuel cells as is for all modern maned or cargo carrying craft.

The CST-100 team was in a tough situation.  On one side, they had a company that was adverse to a lot of risk, and on the other side, they had a project that demanded to take on a lot of risk.  So the design reflected lower risk.  I applaud the team for their excellent work in such a tough situation.  Is CST-100 really what we need to advance commercial space?  Maybe.  Time will tell.  It is not the best.  It was design for five people but can fit seven.  On the other hand SapceX Dragon 2 was designed for seven people.  Dragon 2 is a riskier program to build.  CST-100 has a better chance at success.  I think both will make it.  I can't stress enough how extraordinary it was for Boeing to take on this project in the first place.  There was never a manned capsule made in Boeing's name.  Instead Boeing bought McDonnell Douglas who had made both the Mercury and the Gemini capsules (late 1950's to early 1960;s).  These are on display at the St Louis Science Center.  I took pictures of them - seen above.  They are strikingly small.  So small that they look like some mesh between modern art and engineering built around humans.  This is a really risky project for Boeing.  I applaud them in taking this leap.