shuttle replacement

bob haller safety advocate wrote:
http://spaceflightnow.com/news/n1007/21boeing/

What is missing from the discussion 'until now :-)' is the operational cost of
all these alternative plans. Do these capsules land on land or water? Are they
reusable? With Orion, I was convinced that at the end of the day we'd end up
with costs nearly equivalent to what we have now with the shuttle. You know
the old saw about the time required to finish a project always expands to fill
the time available? Same goes for cost. You budget at $600 million a flight
and lo and behold that's what it ends up costing you, and it doesn't matter
what shape or form it takes.

I'm not so interested in the style of how you do it as much as I am in the
cost to do it, over and over....

It's that latter part where I see an advantage for a winged reusable vehicle.
But as Derek L. liked to say, it all depends on the flight rate. Right now, I
don't see a rate that would justify it. Maybe Bigelow will be an enabler, but
it isn't clear to me right now that it will be.

Dave

On Jul 30, 7:29*pm, David Spain wrote:
bob haller safety advocate wrote:

http://spaceflightnow.com/news/n1007/21boeing/

What is missing from the discussion 'until now :-)' is the operational cost of
all these alternative plans. Do these capsules land on land or water? Are they
reusable? With Orion, I was convinced that at the end of the day we'd end up
with costs nearly equivalent to what we have now with the shuttle. You know
the old saw about the time required to finish a project always expands to fill
the time available? Same goes for cost. You budget at $600 million a flight
and lo and behold that's what it ends up costing you, and it doesn't matter
what shape or form it takes.

I'm not so interested in the style of how you do it as much as I am in the
cost to do it, over and over....

It's that latter part where I see an advantage for a winged reusable vehicle.
But as Derek L. liked to say, it all depends on the flight rate. Right now, I
don't see a rate that would justify it. Maybe Bigelow will be an enabler, but
it isn't clear to me right now that it will be.

Dave

well assuming the capsule can land on both water and land in a
emergency that would elminate another fkight constraint.

in a real bad day land anywhere

bob haller safety advocate wrote:

well assuming the capsule can land on both water and land in a
emergency that would elminate another fkight constraint.

Only routinely being able to land at a PREPARED facility really eliminates
any useful flight constraint.

Screw preparing for emergencies, prepare for the routine.

That's one thing that the shuttle "sort of" got right. landing within miles
of where it took off (sometimes) and making a short ride over to being
refurbed.

Everyone seems to want to ignore the cost of the standing navy for water
landing craft.



in a real bad day land anywhere

--
Greg Moore
Ask me about lily, an RPI based CMC.

On 7/30/2010 3:29 PM, David Spain wrote:


What is missing from the discussion 'until now :-)' is the operational
cost of all these alternative plans. Do these capsules land on land or
water? Are they reusable?

If you wanted to save a lot of money and weight, you would jettison a
ablative heatshield after reentry - since it can't be reused, and any
sort of reusable one is probably going be too fragile to survive impact
with the sea or ground.
That's what the Russians do with Soyuz to greatly cut down the overall
weight of the descent module and parachute size needed for landing...
and something we were heading for back in Project Mercury, although in
our case the heatshield stayed attached to the base of the capsule by a
fabric cylinder with holes in it to act as a air compression shock
absorber on sea impact to cut down overall G-loads on the astronaut.
In the case of Orion, the original heatshield was a odd hybrid of
expendable and reusable; three or four blow-off ablative panels would
detach from it after reentry, letting landing legs or airbags extend for
a hard surface touchdown, yet the majority of the heatshield would be
reusable.
This, like the Shuttle, was a case where technological "sweetness" was
being allowed to overpower the bottom line in operating costs.

Pat

On 7/30/2010 4:02 PM, Greg D. Moore (Strider) wrote:


That's one thing that the shuttle "sort of" got right. landing within miles
of where it took off (sometimes) and making a short ride over to being
refurbed.

What Shuttle didn't get right was the need for acceptable weather at KSC
for a RTLS abort, and on the far side of the Atlantic for sub-orbital
aborts.
Not even to mention all the Shuttle returns that were delayed in landing
at KSC or went to Edwards as a alternate landing site due to weather
problems at KSC.
That's something that needs correcting on a future launch system; it
should go up and return in the same sort of weather a airliner would
find acceptable to operate in.
(Although from my old days as a FAA contract weather observer at
Jamestown Airport, I can remember looking out the window to the north
and seeing this solid black wall of rain from horizon-to-horizon heading
towards us, and telling an incoming regional airliner: "You know
something? Not only would I recommend not attempting a landing here...if
I were you, I'd get the hell as far away from here as possible, ASAP."
They took that advice and probably avoided getting slammed into the
ground by a squall line with zero visibility when all **** broke loose
around five minutes later. Technically, I was only supposed to report
the weather conditions to the incoming aircraft, and not give them any
sort of advice about what to do, as Jamestown Airport is uncontrolled
airspace. I simply decided that I didn't want twenty dead people on my
conscience, and said "Screw The Rules".)

Pat

On Sat, 31 Jul 2010 04:17:05 -0800, Pat Flannery
wrote:


What Shuttle didn't get right was the need for acceptable weather at KSC
for a RTLS abort, and on the far side of the Atlantic for sub-orbital
aborts

True, but in the end those limitations didn't have much impact,
because Shuttle flight-rate never rose high enough for the diverted
landings to significantly affect schedules.

Not even to mention all the Shuttle returns that were delayed in landing
at KSC or went to Edwards as a alternate landing site due to weather
problems at KSC.

Ditto.

That's something that needs correcting on a future launch system;

Why? It would be enormously expensive to build an all-weather
spacecraft, and that will saddle the spacecraft with lots of heavy
'extras' that simply delaying launch or landing 24 hours usually
obviates.

We don't let airliners take off in bad weather, and we divert
airliners to other airports if the weather gets too bad to land, why
demand more of a spacecraft that is unlikely to fly more often than
once every couple of weeks anyway?

We need simpler spacecraft, not more complicated ones.

Brian

Pat Flannery wrote:

What Shuttle didn't get right was the need for acceptable weather at KSC
for a RTLS abort, and on the far side of the Atlantic for sub-orbital
aborts.
Not even to mention all the Shuttle returns that were delayed in landing
at KSC or went to Edwards as a alternate landing site due to weather
problems at KSC.

One would have to wonder how much those rules could have been relaxed
without jeoperdizing safety.

For instance, was RTLS really required if TAL was available ? (or vice
versa). Realistically speaking, if something bad happened during first 2
minutes of flights, was RTLS realistic ?

If the Shuttle gained sufficient energy to go TAL, then was RTLS ever
going to be used ?

Remember that TAL is much more like a conventional landing, whereas RTLS
required manoeuvers that were never attempted in real life.


When you have just a handful of flights per year, you can afford to wait
for good weather. But even with low shuttle flight rate, scheduling
becomes a concern when you consider Progress/Soyuz/HTV/ATV traffic
to/from the station.


Soyuz seems to have the right formula for dependable launch and return
schedules. Perhaps this has more to do with management philosophy
(accepting greater risks), perhaps it is inherent to the simple design
of the Soyuz and its launch location.

Has there been any debate on whether KSC remains the best possible
launch location ?

How about southern California on the Baja peninsula ? Could this allow
both ascending and descending node launches ? Seems to me that weather
is also more cooperative there than in Florida (fewer hurricanes for
instance)

On Sat, 31 Jul 2010 21:42:00 -0400, John Doe wrote:

Has there been any debate on whether KSC remains the best possible
launch location ?

Yes, prior to both Apollo and Shuttle. Final decision was "nowhere in
the Continental US is significantly better, and it is too expensive to
set up shop somewhere else off-continent."

How about southern California on the Baja peninsula ?

That would be in Mexico. Not going to happen.

Could this allow
both ascending and descending node launches ?

Neither.

Brian

On 8/3/2010 5:56 AM, Joseph Nebus wrote:

As I recall there was some thinking in early development of the
Shuttle that White Sands, New Mexico, would be a rather good launch site
allowing for convenient equatorial and polar orbits and also being a
nifty landing site right away. But there was no hope of selling a whole
brand-new launch complex when NASA had barely got done painting the
Vehicle Assembly Building, so, that idea died swiftly.

(And it would turn out to be not so good as a landing site
anyway.)

That would have worked for the Faget concept with the winged booster,
but the chosen design had those two SRBs to recover, and water was a lot
softer than sand to touch them down on. ;-)

Pat

On Aug 3, 1:51*pm, Pat Flannery wrote:
On 8/3/2010 5:56 AM, Joseph Nebus wrote:

* *As I recall there was some thinking in early development of the
Shuttle that White Sands, New Mexico, would be a rather good launch site
allowing for convenient equatorial and polar orbits and also being a
nifty landing site right away. *But there was no hope of selling a whole
brand-new launch complex when NASA had barely got done painting the
Vehicle Assembly Building, so, that idea died swiftly.

* *(And it would turn out to be not so good as a landing site
anyway.)

That would have worked for the Faget concept with the winged booster,
but the chosen design had those two SRBs to recover, and water was a lot
softer than sand to touch them down on. ;-)

Pat

loaded bombs should never overfly populated areas at all because
accidents can occur.....

KSC is a excellent facility and should remain the countries space port