SS1 -- one down, one to go!

"Neil Gerace" wrote in message
...

"Rand Simberg" wrote in message
...
On Thu, 30 Sep 2004 13:22:55 +0200, in a place far, far away, "Tamas
Feher" made the phosphor on my monitor glow in

Remember what Korolev said: three successful unmanned flights for any
space hardware before people are allowed to ride it.

Well, if Korolev said it, it must be true...

Except for the Saturn V. Or the Shuttle.

Each Saturn V was flown only once

So where all of Korolev's vehicles. ;-)

(Mike Flugennock) wrote:

As for the Shuttle, I guess we can't really count things like the piloted
drop tests. It's not like it couldn't have landed on its own, could it?

It's *exactly* like that. There's no fundamental reason that it *must* be
that way, but as designed there is no way for anyone but an onboard human
to lower the landing gear.

h (Rand Simberg) wrote in message .. .

Remember what Korolev said: three successful unmanned flights for
any
space hardware before people are allowed to ride it.

Well, if Korolev said it, it must be true...

Except for the Saturn V. Or the Shuttle.

Or the X-15.

This is time-proven wisdom.

It is non-proven opinion.

And one that incorporates a value judgment about the importance of
human life, by a man who was working for a government that valued
party politics much more highly than human life.

On Thu, 30 Sep 2004 23:55:31 GMT, in a place far, far away,
(Alan Anderson) made the phosphor on my monitor
glow in such a way as to indicate that:

(Mike Flugennock) wrote:

As for the Shuttle, I guess we can't really count things like the piloted
drop tests. It's not like it couldn't have landed on its own, could it?

It's *exactly* like that. There's no fundamental reason that it *must* be
that way, but as designed there is no way for anyone but an onboard human
to lower the landing gear.

Or steer the nose, or brake.

Louis Scheffer :

Finally, a crash of a test plane with a known flaw would hardly cause
irrepairable harm. It has happened may times in aviation, which is still
going strong. In fact, a crash due to a known flaw impedes progress
much less than a crash due to unknown or unforeseen reasons.

Add the fact that SS1 have already crashed once during landing and that did
not stop the SS1 from flying, they just delayed thier next flight till they
fixed the problem.

Earl Colby Pottinger

--
I make public email sent to me! Hydrogen Peroxide Rockets, OpenBeos,
SerialTransfer 3.0, RAMDISK, BoatBuilding, DIY TabletPC. What happened to
the time? http://webhome.idirect.com/~earlcp

"Mike Flugennock" wrote in message
...

As for the Shuttle, I guess we can't really count things like the piloted
drop tests. It's not like it couldn't have landed on its own, could it?
Even so, first time up, carrying a live crew. I was excited at the
prospect of finally getting to see STS fly "for real", but still the whole
time I was thinking "no previous unmanned all-up flight, man, this is
nuts".

Well, one doesn't fly prototype airliners unmanned, and they risk just as
many lives on their first flights, sometimes more.

In article ,
"Neil Gerace" wrote:

"Mike Flugennock" wrote in message
...

As for the Shuttle, I guess we can't really count things like the piloted
drop tests. It's not like it couldn't have landed on its own, could it?
Even so, first time up, carrying a live crew. I was excited at the
prospect of finally getting to see STS fly "for real", but still the whole
time I was thinking "no previous unmanned all-up flight, man, this is
nuts".

Well, one doesn't fly prototype airliners unmanned, and they risk just as
many lives on their first flights, sometimes more.

True, that. Still, _most_ airliners already have previous
engineering/piloting experience coming behind them; STS-1 was the
first-ever-flown complete flight system/hardware of that type. Iirc the
xUSSR flew at least one Buran flight unmanned with an autopilot landing
before the first manned flight which, of course, they never did get a
crack at.

Deftly diving back on-topic, didn't Melvill own up to "pilot error" on
that roll problem? I'd been checking the reports being posted at
SpaceflightNow, and it's apparently looking like that.

If it does turn out to be an actual flaw of some kind, I'm sure that the
version that flies the first post-Concorde generation of bored, rich
jet-setters -- or whatever they'd nickname a bunch of bored, rich,
suborbital ocean-hoppers -- for Virgin Air _won't_ have it.

--
"All over, people changing their votes,
along with their overcoats;
if Adolf Hitler flew in today,
they'd send a limousine anyway!" --the clash.
__________________________________________________ _________________
Mike Flugennock, flugennock at sinkers dot org
Mike Flugennock's Mikey'zine, dubya dubya dubya dot sinkers dot org

On Fri, 01 Oct 2004 01:59:54 +0000, Joann Evans wrote:

Rand Simberg wrote:

On 30 Sep 2004 07:10:36 -0700, in a place far, far away,
made the phosphor on my monitor glow in such a way
as to indicate that:

My opinion, after watching the entire flight on video, is that the SS1
design has a built-in control problem that makes it very difficult to
fly, especially at higher altitudes. A computer might be able to fly
it straight, but no stick and rudder pilot is perfect enough to fly it
pretty every time.

I don't think it's altitude. The fact that it's happening later in the
burn could be because of nozzle erosion. I'm guessing that it doesn't
have enough RCS control authority to muscle past the (unplanned) thrust
asymmetries,

Indeed, this prospect, non-symmetrical nozzle ablation, was
explicitly mentioned in Aviation Week, after the first 100km flight, and
I'm inclined to agree. Near peak altitude, thrusters would be
inadequate, and there's not enough atmosphere for control surfaces.




Non-symmetrical nozzle ablation might make it harder to trim SS1. The trim
is always changing during powered flight.

The way SS1 spun up in roll, maybe the electric actuator overheated again
and shut down and he didn't reset it right away. SS1 appeared to spin up
at a constant roll acceleration and it appeared that nothing was being
done to stop it. Like control just stopped, and stability took over. Maybe
he just rode it out and reset it after it had time to cool, and that's why
the pilot blamed himself for the roll. Using the actuator too much.

If the actuator were to burn out during ascent, the horizontal stabilizers
might become stuck at an adverse trim location. Then SS1 would be
uncontrollable during subsonic flight.

Even if the actuator doesn't get stuck, maybe it takes more that two weeks
to change them out if they are severely overheated. Maybe a conscious
decision was made to not reset it right away, but rather just ride it out
or shut the engine off and try again another day.

Craig Fink
Badnarik for President http://www.badnarik.org

On Thu, 30 Sep 2004 15:58:37 +0000, Craig Fink wrote:

On Thu, 30 Sep 2004 15:33:52 +0000, Rand Simberg wrote:

On Thu, 30 Sep 2004 15:19:38 GMT, in a place far, far away, Craig Fink
made the phosphor on my monitor glow in such a way
as to indicate that:

If so, this is a problem that could be solved with a better engine
nozzle design.

The nozzle is fine, it's symmetric.

Not after it erodes...

One of the articles said that they see the roll in their simulations.
They don't have eroded nozzles. Nonsymetrical erosion, or maybe
nonsymetrical burning of the rubber fuel in the motor. But, most if not
all is in the aerodynamic design.

http://www.space.com/missionlaunches...ht_040929.html

Pictures that show the wing and rudder above the cg, causing roll to be
coupled to angle of sideslip.

http://www.scaled.com/projects/tiero...eral/og_ff_800

http://www.scaled.com/projects/tiero...l/LANDING2_800

The rudders should be larger on the bottom not the top to reduce
yaw/roll coupling. It also looks like they have clearance to do this.



http://dbs.cordis.lu/cgi-bin/srchida...N_RCN_ID:22705

'Did I plan the roll? I'd like to say I did, but I didn't,' admitted Mr
Melville. 'You're extremely busy at that point. Probably I stepped on
something too quickly and caused the roll, but it's nice to do a roll at
the top of the climb.'

If he stepped on the manual rudder, he's moving the upper part of the
rudder. That part of the rudder is way above the cg, so you would expect
it to cause a lot of roll moment with the yaw moment. The electric yaw
trim is on the lower part of the rudder.

http://www.scaled.com/projects/tiero...DF/Posterboard - SpaceShipOne.pdf

Maybe once the roll got started, the control surfaces became ineffective
and the roll continued to accelerate.

Craig Fink
Badnarik for President http://www.badnarik.org Don't go to the polls as
ignorant as CNN, MSNBC, FOXNEW,... would like you to be.

"Mike Flugennock" wrote in message
...

True, that. Still, _most_ airliners already have previous
engineering/piloting experience coming behind them;

Yes, most do ... but the first flights of a whole bunch of ground-breaking
(well, perhaps that's not the best term) aircraft were manned too

Deftly diving back on-topic, didn't Melvill own up to "pilot error" on
that roll problem? I'd been checking the reports being posted at
SpaceflightNow, and it's apparently looking like that.

That is what I heard this morning, yes.

If it does turn out to be an actual flaw of some kind, I'm sure that the
version that flies the first post-Concorde generation of bored, rich
jet-setters -- or whatever they'd nickname a bunch of bored, rich,
suborbital ocean-hoppers -- for Virgin Air _won't_ have it.

What's the bet the first working, revenue-generating commercial spaceliner
will be British, and will turn out to have a fatal design fault which could
have been foreseen only in hindsight, which will then be fixed by their
latecoming American rivals, who will corner the market

"Hellooooo, Comet!"