View Single Post
  #22  
Old June 12th 18, 11:44 AM posted to sci.space.policy,sci.physics,sci.astro,rec.arts.sf.science
Jeff Findley[_6_]
external usenet poster
 
Posts: 2,307
Default Towards routine, reusable space launch.

In article , droleary@
2017usenet1.subsume.com says...

For your reference, records indicate that
Jeff Findley wrote:

Balloon launch isn't worth the trades which have to be made, IMHO.


Certainly not today, no, or people would be doing it. But as I keep
saying, new technologies keep popping up all the time that might make
it viable in the future, at least for a few use cases.


I have an engineering degree. When developing new things, engineers
work with what they have today because they've got schedules and
deadlines to meet. You're talking about technologies not yet invented.
That's research, not development. The two are not the same.

By your definition, a passenger carrying aircraft is "waste" because it
flies from one destination to another while carrying passengers.


Yes; that is true by any definition. Just because it?s (arguably) the
least wasteful mode of transportation we currently have says nothing
about how we might travel in the future.


Again, to an engineer the future is what you can do with existing tech.
SpaceX has reduced launch costs beyond what any of the competition can
deliver. They arguably didn't use any new technology at all. DC-X
proved VTVL as a viable take of and landing mode. SpaceX applied that
to Falcon 9's first stage.

They don't give a rat's ass about the "waste" of the
actual aircraft having to fly there and back.


That same logic could have been used regarding ship or train travel
prior to the airplane?s dominance. The point being that they *will*
care as soon as a new technology comes along that allows more
efficient travel. What that might be in reality is unknown, but
clearly something like teleportation or Futurama-style tubes are
sci-fi ways of moving just the bits that need to be moved from one
location to another.


Actually moving freight by rail is the cheapest way to move a ton of
goods from point a to point b, assuming you can connect the two by rail.
Aircraft have the advantage of speed, so your Amazon order gets there
overnight instead of in a week or two, but you're paying for Amazon
Prime, which isn't exactly cheap now is it?

Two different sets of requirements lead to two completely different
vehicles. That's how engineering optimization works.

When your hardware costs more than two
orders of magnitude more than your propellant does, it makes a hell of a
lot of sense to "expend" a bit of propellant to get your expensive
hardware back intact.


Yes. And I?m just wondering why you can?t just take the next step and
admit that eliminating that expensive hardware *completely* would
represent a cost saving of two orders of magnitude! You wrote it, but
it?s like you weren?t really thinking about what your words actually
meant.


As an engineer I quite simply can't do that. There is no *proven*
existing tech that is cheaper than liquid fueled rocket engines for
reaching orbit.

What you are trying to get me to admit is that eventually, some day,
there may be something better. Sure, there might. Also, monkeys might
fly out of my butt. I'm not waiting for sci-fi to become reality. I'm
working with what I've got today. Again, that's what engineers do.

Jeff

--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.