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Posted by Andy Summers (Member # 3207) on 07-25-2005, 09:16 PM:
 
Discovery Ready for Launch
The Space Shuttle Discovery and its seven-member crew are ready for launch at 10:39 a.m. EDT on Tuesday, July 26.

STS-114 -- the first Shuttle mission in more than two years -- is set to test new safety procedures and deliver supplies and equipment to the International Space Station
Well I wish Discovery, a safe journey after 2 years been, grounded after Columbia ill fated mission…

God speed Discovery…

http://www.nasa.gov/returntoflight/main/index.html

There is still more testing to be done," space shuttle Discovery Commander Eileen Collins said while standing on the deck of the space center's neutral buoyancy lab — an indoor pool that contains mock-ups of the shuttle and International Space Station where astronauts practice spacewalks.

Hears a little something about launching, the Space Shuttle.

While we prepare for STS-114 Discovery return to flight status.

http://kids.msfc.nasa.gov/rockets/shuttle/launch.asp
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-25-2005, 09:35 PM:
 
I wish I could agree with that statement. They still don't know what the exact problem is with the low fuel sensor and they are ready to issue a launch waiver without knowing what is really wrong. It seems to me that NASA still has the WRONG mentality for playing with this sort of equipment. Clearly, they are NOT ready to launch it.

A shuttle engineer with 14 years experience has this to say about it......

That disappoints former NASA shuttle engineer Randy Avera, a 14-year veteran of the orbiter program who participated in the investigation into the explosion that destroyed the shuttle Challenger in 1986.

"It disturbs me that in the first countdown attempt, a problem on the vehicle -- where it is known but not identified what the problem is -- that so quickly discussions about waiving the launch commit criteria surface," Avera said.

If a waiver is issued, and NASA launches Tuesday with the same indication of a problem it had last week, Avera wants NASA to release the documentation that details why it issued the waiver.

"What I'm looking for is NASA to come forward with the actual basis for that waiver," Avera said. "And that basis should be linked directly to design requirements and operational requirements."
 

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Posted by Andy Summers (Member # 3207) on 07-25-2005, 09:52 PM:
 
Hello there

Mark

It is also said the Space Shuttle is the most complex machine ever built by man, clearly she is a compacted bird, she must be 100% flight ready not 99.999, but the crew know this, they know that the unforeseen can not always be seen, and the challenges this brave crew must face if one does arise, and to deal with the problem as fast and as professional, without losing your head…

Mark I’ll give my left arm to ride the Space Shuttle, and to look down upon the earth and see England passing by every 90mins at 18,000ft per sec…

So are your keeping your fingers (X), I am “God Speed STS-114 Discovery Safe Journey”.

http://www.nasa.gov/multimedia/videogallery/index.html

Also hear is a way to track the Space Shuttle when she's off the launch Pad 39B and in orbit.
http://science.nasa.gov/temp/ShuttleLoc.html

On October 14, 1947, in the rocket powered Bell X-1, Capt. Charles E. Yeager flew faster than sound for the first time.

To see where the (ISS) International Space Station is currently in orbit around the earth, and if she is going to pass over where you live, then step outside and you will see a very bright object moving at 18,000ft per sec, that’s fast, and only takes 90mins for her to complete an orbit so get looking.
http://science.nasa.gov/temp/StationLoc.html

[ 07-26-2005, 07:35 PM: Message edited by: Andy Summers ]
 

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Posted by Joe Redifer (Member # 3) on 07-25-2005, 10:15 PM:
 
We as a country are way too incompetant to launch a nearly 30 year old shuttle. Why we can't use the old parts that worked countless times before is beyond me. Morons. They really need to ditch the shuttle and catch up to at least 1990 technology. We also need a ship that actually goes into space. I don't consider where the space shuttle goes actual "space", just orbit. Yawn. Fly that sucker around!

This is all very embarrasing.
 

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Posted by Darryl Spicer (Member # 711) on 07-25-2005, 10:20 PM:
 
and they can start by updating their computer systems to Macintoshes.
 

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Posted by Joe Redifer (Member # 3) on 07-25-2005, 10:23 PM:
 
Knowing NASA, they'd get 50 System 6.0 Macs (1 for the actual work, 49 for back ups) and pay $2 million EACH for them. NASA is smart.
 

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Posted by Andy Summers (Member # 3207) on 07-25-2005, 10:31 PM:
 
Come on guys, give them a break will you….
 

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Posted by David Stambaugh (Member # 1102) on 07-25-2005, 10:31 PM:
 
I'm prolly gonna be get bitch-slapped for saying this...

Joe, you should wish AIDS on everyone at NASA! That's like your funniest line! Ha ha ha.


 

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Posted by Andy Summers (Member # 3207) on 07-25-2005, 10:44 PM:
 
I’m very excited about this, it’s like April 14 1982, man I would have liked to see Columbia launch back then when I went to Florida back in early February 1982 ,and the visit to the Kennedy Space centre, was out of this world…

http://science.ksc.nasa.gov/shuttle/missions/sts-1/images/79HC206.GIF

April 12, 1981 - The first space shuttle flight occurred with the launching of Columbia with astronauts John Young and Robert Crippen aboard. Columbia spent 54 hours in space, making 36 orbits, then landed at Edwards Air Force Base in California
 

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Posted by Lyle Romer (Member # 1266) on 07-25-2005, 10:48 PM:
 

quote: Joe Redifer

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Why we can't use the old parts that worked countless times before is beyond me.

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quote: Greg Anderson

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NASA has had nothing else that could put a man into space.

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Of course, you also didn't hear about the shuttle until a few years before the testing phase began. I wouldn't expect them to unveil anything in the works until its design is near completed.

Andy,
Sorry chap, but the shuttle flies around England in its orbit so you wouldn't see a thing........ .

Joe,
You don't consider over 200 miles up very far from the ground?

Mark
 

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Posted by Andy Summers (Member # 3207) on 07-26-2005, 01:49 AM:
 
Hello there

Mark

Are that’s low numbers, oh well I’ve got the (J-tracking) so I’ll be keeping an eye on her, even if she wont pass overhead.

I’ve seen the (ISS) at least three times in the past during the winter time, when the sky’s get darker fast and makes for great astronomical viewing…

Catch you later going to catch a few zzz zzz before the launch

[ 07-26-2005, 07:36 PM: Message edited by: Andy Summers ]
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-26-2005, 02:11 AM:
 
Andy,
I'm just yanking your chain , of course it flies over England.

Here are some amazing facts about the Space Shuttle Main Engines...... These promises have been lived up to and just for Greg.
______________________________________________

Rocketdyne's Space Shuttle Main Engine operates at greater temperature extremes than any mechanical system in common use today. The liquid hydrogen fuel is -423 degrees Fahrenheit, the second coldest liquid on Earth. When the hydrogen is burned with liquid oxygen, the temperature in the engine's combustion chamber reaches +6000 degrees Fahrenheit - that's higher than the boiling point of Iron.

The maximum equivalent horsepower developed by the three SSMEs is just over 37 million horsepower.

The energy released by three of Rocketdyne's Space Shuttle Main engines is equivalent to the output of 13 Hoover Dams.

Although not much larger than an automobile engine, the SSME high-pressure fuel turbopump generates 100 horsepower for each pound of its weight, while an automobile engine generates about one-half horsepower for each pound of its weight.

Even though Rocketdyne's SSME weighs one-seventh as much as a locomotive engine, its high-pressure fuel pump alone delivers as much horsepower as 28 locomotives, while its high-pressure oxidizer pump delivers the equivalent horsepower for 11 more.

If water, instead of fuel, were pumped by the three Space Shuttle Main Engines, an average family-sized swimming pool could be drained in 25 seconds.

The SSME high-pressure fuel turbopump main shaft rotates at 37,000 rpm compared to about 3,000 rpm for an automobile operating at 60 mph.

The discharge pressure of an SSME high-pressure fuel turbopump could send a column of liquid hydrogen 36 miles in the air
__________________________________________

They forgot to mention that the turbopumps go from stand still to 37,000 rpm in less than two seconds! Now thats really pickin up steam in a hurry .

Mark
 

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Posted by Joe Redifer (Member # 3) on 07-26-2005, 03:56 AM:
 
200 miles up is indeed far, but not exactly what I would call "the outer limits". I think NASA should start impressing us again. Screw the space station, let it burn up. Until we start storing nukes up there, it is of no importance. I don't care how a certain strain of amoebas reproduce in zero gravity. I want to blow up planets!

quote: Mark Gulbrandsen

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If water, instead of fuel, were pumped by the three Space Shuttle Main Engines, an average family-sized swimming pool could be drained in 25 seconds.

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quote: Mark Gulbrandsen

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Rocketdyne's Space Shuttle Main Engine operates at greater temperature extremes than any mechanical system in common use today. The liquid hydrogen fuel is -423 degrees Fahrenheit, the second coldest liquid on Earth. When the hydrogen is burned with liquid oxygen, the temperature in the engine's combustion chamber reaches +6000 degrees Fahrenheit - that's higher than the boiling point of Iron.

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and what keeps the engine bell from melting down from the high temps. The answer is the liquid hydrogen is fed through circular tubes that run through the engine bell on it's way to the cumbustion chamber. Thus the -423 degree temp keeps the bell cool.
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-26-2005, 09:32 AM:
 
Darryl,

The Nozzel itself is actually made of lengths of welded titanuim tubing, I ahve a cutaway photo someplace and will look for it tonight. This tubing is cinntcted at the top and bottom by circular ducts for the liquid hydrogen. The hydrogen circulates into the upper duct down though the tubing and out to the combustion chamber through the lower duct. Also note that it is circulated by the LP turbo pumps at several hundred psi, not the high pressire pumps which operate at thousands of pounds of pressure. The feed to and from the nozzel is between the two pumps.

Mark
 

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Posted by Floyd Justin Newton (Member # 1316) on 07-26-2005, 09:53 AM:
 
It's up!
 

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Posted by Andy Summers (Member # 3207) on 07-26-2005, 01:53 PM:
 
Hello there all

Good morning Afternoon and evening…

Mark; that was some wind up I really fail for that one, you Space monkey.

Hi there Darryl are you watching the updates via the NASA television, man that imagining was totally indispensable and out of this world, I felt like the wild coyote…

You bet she’s up wow that is one brave commander they have there, Eileen bring the Discovery and the rest of the crew back home safely and God Speed Discovery.

Joe, man your mind is warped factor 2, Let the ISS burn-up blow up planets, gentlemen, no more Star Wars for that guy….

I’m going stay watching until (Discovery STS-114) touchdowns, by the way where is she landing home port, or out in the desert the dry lake in California.

Bill Readdy Associate Administrator of the Space Operations Mission Directorate
Said today at the NASA press conference

“Your can never let down your guard” (Bill Readdy) 26th July 2005 said this today.

Bill Readdy as fly several missions in the past

(Bill Readdy) was first on (Discovery STS-42) as a Mission Specialist 3 Launch Jan. 22, 1992.

Again on (STS-51 Discovery) serving as Pilot Launch September 12, 1993.

And on (STS-79 Atlantis) was the commander of the Space shuttle Launch September 16, 1996

You can watch updates on the mission of STS-114 return to flight live via NASA television.

http://www.nasa.gov/multimedia/nasatv/

As well as, the (J-Tracking) for the ISS international space station
http://science.nasa.gov/temp/StationLoc.html

Also the (J-Tracking for Discovery STS-114)
http://science.nasa.gov/temp/ShuttleLoc.html

PS, Mark, why man you should this to your interests and hobbies, and why on earth are you not working for NASA man you blow me away.

I’m wondering what other cameras they have onboard (Discovery STS-114) any IMAX cameras!

[ 07-26-2005, 07:33 PM: Message edited by: Andy Summers ]
 

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Posted by Joe Redifer (Member # 3) on 07-26-2005, 04:54 PM:
 
Andy, in English, "Hallo" means "I am a moron".
 

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Posted by Richard Fowler (Member # 893) on 07-26-2005, 05:04 PM:
 
Hallo is O.K. for a German to send regards Great to see the shuttle flying again
 

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Posted by Phil Hill (Member # 371) on 07-26-2005, 06:35 PM:
 
I think the USA should junk the whole "manned" space effort. I mean, with the exception of a some mega$$$ NASA contractors, what is ANYONE gaining by it other than the "prestige" of being an astronaut or the NASA-wigs making "IT" work and patting themselves on the back?

Both NASA and the Shuttle have provided some great new technology over the years, but have LONG outlived their usefulness...dump 'em!

This lastest "fuel gauge" delay is an great example of an out-of-control, lack-of-common-sense NASA gone wild. The over-zealous scientists monitor the monitors that monitor the monitors... It's telemetry gone wild. No wonder private industry can do a better job at space flight.

I'd MUCH rather see all the kabillion $$$ spent on that put to more useful things here on earth....Ummmm for, and to help the citizens of the USA.

Keep the deep-space probes and survey/photo/scientific unmanned missions...those kick ass....

Just my 2-cents...
 

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Posted by Aaron Mehocic (Member # 15) on 07-26-2005, 07:04 PM:
 
Phil,

Granted, but what about all the research that is conducted aboard manned space flights? Medical expermintations, simulation sets for the eventual mission to Mars, space walks and so on and so forth. You are right about the shuttle program being obsolete, yet I'm not quite sure un-manned is the way to go as of now.
 

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Posted by Joe Redifer (Member # 3) on 07-26-2005, 07:46 PM:
 
Phil just wants all the men to stay here on Earth, with him (sorry Phil, couldn't resist. Actually I'm not sorry).
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-26-2005, 07:52 PM:
 
I think it should also stay manned but we need to revive something more practical like the Saturn V and Apollo capsule program because it always worked and pretty flawlessly at that. And until we have a new space telescope to place upstairs we should repair the Hubble via the shuttle no matter how dangerous it is. Hubble has gained us far more knowledge than anything from any space program in existance.

Mark
 

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Posted by Phil Hill (Member # 371) on 07-26-2005, 08:04 PM:
 
You are sooo far out to lunch Joe. I don't care what you say... I have YET to see a good-looking one...nor do I care if you kiss my *astronaut* (ass-or-not).

Aaron: I really don't care if they can make a perfect circle amoeba. (The band "Perfect Circle" is MUCH better!)

Nor do I care if they can grow marijuana in space..OR space-walk! B-O-R-I-N-G!

I do think it's really cool that they take aboard Jr. High and HS student experiments. That is really cool for the interested students and helps them in their education.

BUT! In the long run, I REALLY don't see the value to all that except for some remote possibility that it may help mankind.

Save the rain forests 1st! ...they probably have more "cures" than all the space "experiments" combined. JEEZEUS!
 

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Posted by Andy Summers (Member # 3207) on 07-26-2005, 08:30 PM:
 
Hello there

Mark, Phil

Man must explore, the gift we have been given is not to be wasted, and the exploration of the vast unknown will challenge us to the point where some day the big picture will reveal its self?

And think of Voyager 1 & 2 still out there, and performing there duties incredible 28 years September and August 1977.

http://voyager.jpl.nasa.gov/

http://space.umd.edu/voyager/Voypict.gif
 

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Posted by Phil Hill (Member # 371) on 07-26-2005, 08:48 PM:
 

quote: Andy Summers

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Man must explore, the gift we have been given is not to be wasted, and the exploration of the vast unknown will challenge us to the point where some day the big picture will reveal its self?

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Then let *HIM*, that gave mankind the 'GIFT', pay for it all...

As far as the unmanned space exploration, I agree Andy...those are a few of the MANY unmanned accomplishments!
 

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Posted by Mark J. Marshall (Member # 1409) on 07-26-2005, 10:27 PM:
 
Anyone else watch the launch on HD-Net? That was awesome. They didn't show the external tank camera views at first, but I saw them later on the NASA channel or something.

Also, at a press briefing, NASA showed pics and video of "debris" coming from "somewhere" and passing by the shuttle. They also had two pictures of a bird that apparently didn't realize that that giant thing in front of it was about to move upward into its path... the first photo showed the bird colliding with the top of the shuttle's external tank, and the second showed it falling down the side of the tank. If the collision didn't kill the bird, I imagine that the SRBs finished the job by incinerating it a few seconds later.
 

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Posted by Andy Summers (Member # 3207) on 07-26-2005, 10:38 PM:
 
Did someone say Kentucky Fried Bird? Well I guess that’s what the (SRB Super Roasted Bird) will do to a bird.

Poor creature, NASA does take care of the wildlife in the surrounds, imagine if that was a jet-airplane and sucked into the turbines
 

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Posted by Joe Redifer (Member # 3) on 07-26-2005, 10:57 PM:
 
NASA has its own channel? That must be pretty boring most of the time. What do they show during sweeps?

I don't see why we can't do all of this space stuff for free. Money is just imaginary anyway. We say a little piece of paper has value, but does it really? No. Give up money and do everything for free. Everyone gets everything for free, and as much as they want. Obviously ALL of the world's problems would be solved if we did this, and we'd all hold hands and sing songs in unison about the rainbow or something.
 

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Posted by Daryl C. W. O'Shea (Member # 1303) on 07-27-2005, 12:09 AM:
 

quote: Andy Summers

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imagine if that was a jet-airplane and sucked into the turbines

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quote: Andy Summers

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Man must explore, the gift we have been given is not to be wasted, and the exploration of the vast unknown will challenge us to the point where some day the big picture will reveal its self?

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quote: Andy Summers

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The foam issue that came lose during the accent to orbit, the firing of the (SRB) maybe sending shock waves of low frequency and the air pressures surrounding the Shuttle, this is possible though not sure if it is the case.

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quote: Andy Summers

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but the vibrations are more powerful than the biggest (IMAX sound system) so lets not go to far over the top on these issues shall we.

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quote: Lyle Romer

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If they used the original tank fabrication methods, the Columbia disaster never would have happened. The foam falling off tank problem started on earlier launches after they switched to a no CFC manufacturing process for the foam. They did this to be PC and environmentally friendly even though they could have gotten a waiver to use CFCs due to the extremely minute amount that would be emitted in the manufacturing of a shuttle tank.

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quote: Andy Summers

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Daryl, what is VHDL? Kinder lost on that does it have something to do with projection, or computing, or other.

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quote: Andy Summers

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Hello, Hello there all

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Hello.
 

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Posted by Mike Heenan (Member # 392) on 07-27-2005, 10:14 PM:
 
Hi-diddly-hi there.


 

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Posted by Darryl Spicer (Member # 711) on 07-27-2005, 10:49 PM:
 

quote: Andy Summers

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I saw Columbia on pad 39B before the April launch, though I can see only the top of the EXT and the sides of the wings as the gantry was covering the whole package up from the elements like the weather.

Seeing the mighty Saturn V rocket stacked by the side of the (VAB) I have the photos somewhere, not that It matters.

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When I was on vacation in Florida back in 1975 I visited the Kennedy Space center during the preperation for the launch of the Astronauts meet the Cosmonauts in orbit mission. Very interestin seeing that rocket on the pad. It was then that I saw the display model of the planned shuttle. You pushed a button and it launched the shuttle.

When I visited again in 2002 it was durung one of the shuttle missions it may have been either Discovery or Atlantis. I saw the launch from Sea World. However by the time we got over to the Center the next day we missed the last tour by 15 minutes.
 

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Posted by Randy Stankey (Member # 64) on 07-28-2005, 01:09 AM:
 
Y'Know, this sounds like an evil thing to say but there needs to be a problem with the shuttle every once in a while.

Launching the suttle has become such a routine thing that nobody cares unless something bad happens. Unless there is a problem, nobody pays attention. Wondering if she's going to fly again after the last disaster puts the tension and drama back into space flight... the way it SHOULD be.

I enjoy watching the shuttle go up and I want to know every little detail about it. If I had cable TV I would have NASA Select TV tuened on virtually all the time whenever a shuttle is in the sky. Most people either don't understand things about the shuttle or don't care enough to know. To them, it's no big deal. There's a countdown. There's a big cloud of smoke and the thing goes up. A couple weeks later, down it comes only to repeat a few months later. The only time they pay attention is when there is a big news story about it. I believe Rush Limbaugh's term fits these people well: "Arousal Gappers". (Not that I subscribe to Limbaugh's views. Only this particular piece of jargon.)

If the shuttle doesn't blow up once in a while, the arousal gappers don't care. It's a shame that people have to be that way, but I think it's true.
 

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Posted by Andy Summers (Member # 3207) on 07-28-2005, 01:16 AM:
 
Hello, hello there and good morning America.

Sea world wow, haven’t heard that name in years since early February 1981.

Darryl, I had the two options to go with the rest of my relatives to Sea world or the Kennedy Space Centre, KSC man I wouldn’t think of topping that, guys don’t get me wrong I like sea life as well, hear in Bournemouth Dorset England, we have an ocean center.

Well at the moment I’m looking at the photography that Soichi Noguchi MS1/EV 1lot, JAXA, Japonia, filmed of the EXT on the 26th of July 2005 and the freefall is incredible, man that EXT as got to failing at 25,000mph, its getting smaller and the steady hand Soichi, has there and the concentration to capture this footage is indispensable.

Man wouldn’t what the EXT landing on my home eek, wow its passing over land countries at ludicrous speeds.

Wow that was totally cool filming….

http://www.jsc.nasa.gov/Bios/portraits/noguchi.jpg
 

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Posted by Andy Summers (Member # 3207) on 07-29-2005, 11:00 AM:
 
The crew is staying on the timeline, and operations are going smoothly, pre-flight the engineering folks are doing a smashing job.

Now the hatch is open and the station is healthy, there will be (micro meteor) strikes, other than that tomorrow the (EVA) starts at 3:14am CT 30th July 2005 and there will be repairs to the (CMG2) which is out of service.

The orbiting boom system is a wonderful thing and the data is fantastic, the (SRB)
Have been recovered and will be sent back to the (Cape) for checking over and getting them ready for the next flight.

The review committee is looking at the lots of data, like the nose gear on the orbiter, also the chime (RPM) (ET) doors with the possibility of ice getting in the landing gear doors.

The Atlantis is been looked over, with the new data that as been recovered from mission (STS-114 Discovery) and I’m sure they will be applying the data to the orbiter (Atlantis).

NASA is still over looking the data over and over, “its my guess they have to sure she will be safe for return flight back into re-entry.”

NASA has computer tools programs that can look at the heat-resistant tiles to see if there is something that should not be there.

When you are going at super high speeds though the air, you get a mixing of the turbulence which gives it a hot conduction.
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-29-2005, 11:13 PM:
 
Heres an interesting article on the reliability of the space shuttle written by the late brilliant Physist Richard P. Feynman. He wrote this during the investigation of the Challenger Disaster. He always was an excellent writer able to explain complex things in solid english so all can understand them. He is definately one of the heroes of modern Physics.

Mark

Link

Personal observations on
the reliability of the Shuttle,
by R.P. Feynman

Introduction
It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? Since 1 part in 100,000 would imply that one could put a Shuttle up each day for 300 years expecting to lose only one, we could properly ask "What is the cause of management's fantastic faith in the machinery?"
We have also found that certification criteria used in Flight Readiness Reviews often develop a gradually decreasing strictness. The argument that the same risk was flown before without failure is often accepted as an argument for the safety of accepting it again. Because of this, obvious weaknesses are accepted again and again, sometimes without a sufficiently serious attempt to remedy them, or to delay a flight because of their continued presence.

There are several sources of information. There are published criteria for certification, including a history of modifications in the form of waivers and deviations. In addition, the records of the Flight Readiness Reviews for each flight document the arguments used to accept the risks of the flight. Information was obtained from the direct testimony and the reports of the range safety officer, Louis J. Ullian, with respect to the history of success of solid fuel rockets. There was a further study by him (as chairman of the launch abort safety panel (LASP)) in an attempt to determine the risks involved in possible accidents leading to radioactive contamination from attempting to fly a plutonium power supply (RTG) for future planetary missions. The NASA study of the same question is also available. For the History of the Space Shuttle Main Engines, interviews with management and engineers at Marshall, and informal interviews with engineers at Rocketdyne, were made. An independent (Cal Tech) mechanical engineer who consulted for NASA about engines was also interviewed informally. A visit to Johnson was made to gather information on the reliability of the avionics (computers, sensors, and effectors). Finally there is a report "A Review of Certification Practices, Potentially Applicable to Man-rated Reusable Rocket Engines," prepared at the Jet Propulsion Laboratory by N. Moore, et al., in February, 1986, for NASA Headquarters, Office of Space Flight. It deals with the methods used by the FAA and the military to certify their gas turbine and rocket engines. These authors were also interviewed informally.

Solid Rockets (SRB)
An estimate of the reliability of solid rockets was made by the range safety officer, by studying the experience of all previous rocket flights. Out of a total of nearly 2,900 flights, 121 failed (1 in 25). This includes, however, what may be called, early errors, rockets flown for the first few times in which design errors are discovered and fixed. A more reasonable figure for the mature rockets might be 1 in 50. With special care in the selection of parts and in inspection, a figure of below 1 in 100 might be achieved but 1 in 1,000 is probably not attainable with today's technology. (Since there are two rockets on the Shuttle, these rocket failure rates must be doubled to get Shuttle failure rates from Solid Rocket Booster failure.)
NASA officials argue that the figure is much lower. They point out that these figures are for unmanned rockets but since the Shuttle is a manned vehicle "the probability of mission success is necessarily very close to 1.0." It is not very clear what this phrase means. Does it mean it is close to 1 or that it ought to be close to 1? They go on to explain "Historically this extremely high degree of mission success has given rise to a difference in philosophy between manned space flight programs and unmanned programs; i.e., numerical probability usage versus engineering judgment." (These quotations are from "Space Shuttle Data for Planetary Mission RTG Safety Analysis," Pages 3-1, 3-1, February 15, 1985, NASA, JSC.) It is true that if the probability of failure was as low as 1 in 100,000 it would take an inordinate number of tests to determine it ( you would get nothing but a string of perfect flights from which no precise figure, other than that the probability is likely less than the number of such flights in the string so far). But, if the real probability is not so small, flights would show troubles, near failures, and possible actual failures with a reasonable number of trials. and standard statistical methods could give a reasonable estimate. In fact, previous NASA experience had shown, on occasion, just such difficulties, near accidents, and accidents, all giving warning that the probability of flight failure was not so very small. The inconsistency of the argument not to determine reliability through historical experience, as the range safety officer did, is that NASA also appeals to history, beginning "Historically this high degree of mission success..."

Finally, if we are to replace standard numerical probability usage with engineering judgment, why do we find such an enormous disparity between the management estimate and the judgment of the engineers? It would appear that, for whatever purpose, be it for internal or external consumption, the management of NASA exaggerates the reliability of its product, to the point of fantasy.

The history of the certification and Flight Readiness Reviews will not be repeated here. (See other part of Commission reports.) The phenomenon of accepting for flight, seals that had shown erosion and blow-by in previous flights, is very clear. The Challenger flight is an excellent example. There are several references to flights that had gone before. The acceptance and success of these flights is taken as evidence of safety. But erosion and blow-by are not what the design expected. They are warnings that something is wrong. The equipment is not operating as expected, and therefore there is a danger that it can operate with even wider deviations in this unexpected and not thoroughly understood way. The fact that this danger did not lead to a catastrophe before is no guarantee that it will not the next time, unless it is completely understood. When playing Russian roulette the fact that the first shot got off safely is little comfort for the next. The origin and consequences of the erosion and blow-by were not understood. They did not occur equally on all flights and all joints; sometimes more, and sometimes less. Why not sometime, when whatever conditions determined it were right, still more leading to catastrophe?

In spite of these variations from case to case, officials behaved as if they understood it, giving apparently logical arguments to each other often depending on the "success" of previous flights. For example. in determining if flight 51-L was safe to fly in the face of ring erosion in flight 51-C, it was noted that the erosion depth was only one-third of the radius. It had been noted in an experiment cutting the ring that cutting it as deep as one radius was necessary before the ring failed. Instead of being very concerned that variations of poorly understood conditions might reasonably create a deeper erosion this time, it was asserted, there was "a safety factor of three." This is a strange use of the engineer's term ,"safety factor." If a bridge is built to withstand a certain load without the beams permanently deforming, cracking, or breaking, it may be designed for the materials used to actually stand up under three times the load. This "safety factor" is to allow for uncertain excesses of load, or unknown extra loads, or weaknesses in the material that might have unexpected flaws, etc. If now the expected load comes on to the new bridge and a crack appears in a beam, this is a failure of the design. There was no safety factor at all; even though the bridge did not actually collapse because the crack went only one-third of the way through the beam. The O-rings of the Solid Rocket Boosters were not designed to erode. Erosion was a clue that something was wrong. Erosion was not something from which safety can be inferred.

There was no way, without full understanding, that one could have confidence that conditions the next time might not produce erosion three times more severe than the time before. Nevertheless, officials fooled themselves into thinking they had such understanding and confidence, in spite of the peculiar variations from case to case. A mathematical model was made to calculate erosion. This was a model based not on physical understanding but on empirical curve fitting. To be more detailed, it was supposed a stream of hot gas impinged on the O-ring material, and the heat was determined at the point of stagnation (so far, with reasonable physical, thermodynamic laws). But to determine how much rubber eroded it was assumed this depended only on this heat by a formula suggested by data on a similar material. A logarithmic plot suggested a straight line, so it was supposed that the erosion varied as the .58 power of the heat, the .58 being determined by a nearest fit. At any rate, adjusting some other numbers, it was determined that the model agreed with the erosion (to depth of one-third the radius of the ring). There is nothing much so wrong with this as believing the answer! Uncertainties appear everywhere. How strong the gas stream might be was unpredictable, it depended on holes formed in the putty. Blow-by showed that the ring might fail even though not, or only partially eroded through. The empirical formula was known to be uncertain, for it did not go directly through the very data points by which it was determined. There were a cloud of points some twice above, and some twice below the fitted curve, so erosions twice predicted were reasonable from that cause alone. Similar uncertainties surrounded the other constants in the formula, etc., etc. When using a mathematical model careful attention must be given to uncertainties in the model.

Liquid Fuel Engine (SSME)
During the flight of 51-L the three Space Shuttle Main Engines all worked perfectly, even, at the last moment, beginning to shut down the engines as the fuel supply began to fail. The question arises, however, as to whether, had it failed, and we were to investigate it in as much detail as we did the Solid Rocket Booster, we would find a similar lack of attention to faults and a deteriorating reliability. In other words, were the organization weaknesses that contributed to the accident confined to the Solid Rocket Booster sector or were they a more general characteristic of NASA? To that end the Space Shuttle Main Engines and the avionics were both investigated. No similar study of the Orbiter, or the External Tank were made.
The engine is a much more complicated structure than the Solid Rocket Booster, and a great deal more detailed engineering goes into it. Generally, the engineering seems to be of high quality and apparently considerable attention is paid to deficiencies and faults found in operation.

The usual way that such engines are designed (for military or civilian aircraft) may be called the component system, or bottom-up design. First it is necessary to thoroughly understand the properties and limitations of the materials to be used (for turbine blades, for example), and tests are begun in experimental rigs to determine those. With this knowledge larger component parts (such as bearings) are designed and tested individually. As deficiencies and design errors are noted they are corrected and verified with further testing. Since one tests only parts at a time these tests and modifications are not overly expensive. Finally one works up to the final design of the entire engine, to the necessary specifications. There is a good chance, by this time that the engine will generally succeed, or that any failures are easily isolated and analyzed because the failure modes, limitations of materials, etc., are so well understood. There is a very good chance that the modifications to the engine to get around the final difficulties are not very hard to make, for most of the serious problems have already been discovered and dealt with in the earlier, less expensive, stages of the process.

The Space Shuttle Main Engine was handled in a different manner, top down, we might say. The engine was designed and put together all at once with relatively little detailed preliminary study of the material and components. Then when troubles are found in the bearings, turbine blades, coolant pipes, etc., it is more expensive and difficult to discover the causes and make changes. For example, cracks have been found in the turbine blades of the high pressure oxygen turbopump. Are they caused by flaws in the material, the effect of the oxygen atmosphere on the properties of the material, the thermal stresses of startup or shutdown, the vibration and stresses of steady running, or mainly at some resonance at certain speeds, etc.? How long can we run from crack initiation to crack failure, and how does this depend on power level? Using the completed engine as a test bed to resolve such questions is extremely expensive. One does not wish to lose an entire engine in order to find out where and how failure occurs. Yet, an accurate knowledge of this information is essential to acquire a confidence in the engine reliability in use. Without detailed understanding, confidence can not be attained.

A further disadvantage of the top-down method is that, if an understanding of a fault is obtained, a simple fix, such as a new shape for the turbine housing, may be impossible to implement without a redesign of the entire engine.

The Space Shuttle Main Engine is a very remarkable machine. It has a greater ratio of thrust to weight than any previous engine. It is built at the edge of, or outside of, previous engineering experience. Therefore, as expected, many different kinds of flaws and difficulties have turned up. Because, unfortunately, it was built in the top-down manner, they are difficult to find and fix. The design aim of a lifetime of 55 missions equivalent firings (27,000 seconds of operation, either in a mission of 500 seconds, or on a test stand) has not been obtained. The engine now requires very frequent maintenance and replacement of important parts, such as turbopumps, bearings, sheet metal housings, etc. The high-pressure fuel turbopump had to be replaced every three or four mission equivalents (although that may have been fixed, now) and the high pressure oxygen turbopump every five or six. This is at most ten percent of the original specification. But our main concern here is the determination of reliability.

In a total of about 250,000 seconds of operation, the engines have failed seriously perhaps 16 times. Engineering pays close attention to these failings and tries to remedy them as quickly as possible. This it does by test studies on special rigs experimentally designed for the flaws in question, by careful inspection of the engine for suggestive clues (like cracks), and by considerable study and analysis. In this way, in spite of the difficulties of top-down design, through hard work, many of the problems have apparently been solved.

A list of some of the problems follows. Those followed by an asterisk (*) are probably solved:

Turbine blade cracks in high pressure fuel turbopumps (HPFTP). (May have been solved.)
Turbine blade cracks in high pressure oxygen turbopumps (HPOTP).
Augmented Spark Igniter (ASI) line rupture.*
Purge check valve failure.*
ASI chamber erosion.*
HPFTP turbine sheet metal cracking.
HPFTP coolant liner failure.*
Main combustion chamber outlet elbow failure.*
Main combustion chamber inlet elbow weld offset.*
HPOTP subsynchronous whirl.*
Flight acceleration safety cutoff system (partial failure in a redundant system).*
Bearing spalling (partially solved).
A vibration at 4,000 Hertz making some engines inoperable, etc.
Many of these solved problems are the early difficulties of a new design, for 13 of them occurred in the first 125,000 seconds and only three in the second 125,000 seconds. Naturally, one can never be sure that all the bugs are out, and, for some, the fix may not have addressed the true cause. Thus, it is not unreasonable to guess there may be at least one surprise in the next 250,000 seconds, a probability of 1/500 per engine per mission. On a mission there are three engines, but some accidents would possibly be contained, and only affect one engine. The system can abort with only two engines. Therefore let us say that the unknown suprises do not, even of themselves, permit us to guess that the probability of mission failure do to the Space Shuttle Main Engine is less than 1/500. To this we must add the chance of failure from known, but as yet unsolved, problems (those without the asterisk in the list above). These we discuss below. (Engineers at Rocketdyne, the manufacturer, estimate the total probability as 1/10,000. Engineers at marshal estimate it as 1/300, while NASA management, to whom these engineers report, claims it is 1/100,000. An independent engineer consulting for NASA thought 1 or 2 per 100 a reasonable estimate.)

The history of the certification principles for these engines is confusing and difficult to explain. Initially the rule seems to have been that two sample engines must each have had twice the time operating without failure as the operating time of the engine to be certified (rule of 2x). At least that is the FAA practice, and NASA seems to have adopted it, originally expecting the certified time to be 10 missions (hence 20 missions for each sample). Obviously the best engines to use for comparison would be those of greatest total (flight plus test) operating time -- the so-called "fleet leaders." But what if a third sample and several others fail in a short time? Surely we will not be safe because two were unusual in lasting longer. The short time might be more representative of the real possibilities, and in the spirit of the safety factor of 2, we should only operate at half the time of the short-lived samples.

The slow shift toward decreasing safety factor can be seen in many examples. We take that of the HPFTP turbine blades. First of all the idea of testing an entire engine was abandoned. Each engine number has had many important parts (like the turbopumps themselves) replaced at frequent intervals, so that the rule must be shifted from engines to components. We accept an HPFTP for a certification time if two samples have each run successfully for twice that time (and of course, as a practical matter, no longer insisting that this time be as large as 10 missions). But what is "successfully?" The FAA calls a turbine blade crack a failure, in order, in practice, to really provide a safety factor greater than 2. There is some time that an engine can run between the time a crack originally starts until the time it has grown large enough to fracture. (The FAA is contemplating new rules that take this extra safety time into account, but only if it is very carefully analyzed through known models within a known range of experience and with materials thoroughly tested. None of these conditions apply to the Space Shuttle Main Engine.

Cracks were found in many second stage HPFTP turbine blades. In one case three were found after 1,900 seconds, while in another they were not found after 4,200 seconds, although usually these longer runs showed cracks. To follow this story further we shall have to realize that the stress depends a great deal on the power level. The Challenger flight was to be at, and previous flights had been at, a power level called 104% of rated power level during most of the time the engines were operating. Judging from some material data it is supposed that at the level 104% of rated power level, the time to crack is about twice that at 109% or full power level (FPL). Future flights were to be at this level because of heavier payloads, and many tests were made at this level. Therefore dividing time at 104% by 2, we obtain units called equivalent full power level (EFPL). (Obviously, some uncertainty is introduced by that, but it has not been studied.) The earliest cracks mentioned above occurred at 1,375 EFPL.

Now the certification rule becomes "limit all second stage blades to a maximum of 1,375 seconds EFPL." If one objects that the safety factor of 2 is lost it is pointed out that the one turbine ran for 3,800 seconds EFPL without cracks, and half of this is 1,900 so we are being more conservative. We have fooled ourselves in three ways. First we have only one sample, and it is not the fleet leader, for the other two samples of 3,800 or more seconds had 17 cracked blades between them. (There are 59 blades in the engine.) Next we have abandoned the 2x rule and substituted equal time. And finally, 1,375 is where we did see a crack. We can say that no crack had been found below 1,375, but the last time we looked and saw no cracks was 1,100 seconds EFPL. We do not know when the crack formed between these times, for example cracks may have formed at 1,150 seconds EFPL. (Approximately 2/3 of the blade sets tested in excess of 1,375 seconds EFPL had cracks. Some recent experiments have, indeed, shown cracks as early as 1,150 seconds.) It was important to keep the number high, for the Challenger was to fly an engine very close to the limit by the time the flight was over.

Finally it is claimed that the criteria are not abandoned, and the system is safe, by giving up the FAA convention that there should be no cracks, and considering only a completely fractured blade a failure. With this definition no engine has yet failed. The idea is that since there is sufficient time for a crack to grow to a fracture we can insure that all is safe by inspecting all blades for cracks. If they are found, replace them, and if none are found we have enough time for a safe mission. This makes the crack problem not a flight safety problem, but merely a maintenance problem.

This may in fact be true. But how well do we know that cracks always grow slowly enough that no fracture can occur in a mission? Three engines have run for long times with a few cracked blades (about 3,000 seconds EFPL) with no blades broken off.

But a fix for this cracking may have been found. By changing the blade shape, shot-peening the surface, and covering with insulation to exclude thermal shock, the blades have not cracked so far.

A very similar story appears in the history of certification of the HPOTP, but we shall not give the details here.

It is evident, in summary, that the Flight Readiness Reviews and certification rules show a deterioration for some of the problems of the Space Shuttle Main Engine that is closely analogous to the deterioration seen in the rules for the Solid Rocket Booster.

Avionics
By "avionics" is meant the computer system on the Orbiter as well as its input sensors and output actuators. At first we will restrict ourselves to the computers proper and not be concerned with the reliability of the input information from the sensors of temperature, pressure, etc., nor with whether the computer output is faithfully followed by the actuators of rocket firings, mechanical controls, displays to astronauts, etc.
The computer system is very elaborate, having over 250,000 lines of code. It is responsible, among many other things, for the automatic control of the entire ascent to orbit, and for the descent until well into the atmosphere (below Mach 1) once one button is pushed deciding the landing site desired. It would be possible to make the entire landing automatically (except that the landing gear lowering signal is expressly left out of computer control, and must be provided by the pilot, ostensibly for safety reasons) but such an entirely automatic landing is probably not as safe as a pilot controlled landing. During orbital flight it is used in the control of payloads, in displaying information to the astronauts, and the exchange of information to the ground. It is evident that the safety of flight requires guaranteed accuracy of this elaborate system of computer hardware and software.

In brief, the hardware reliability is ensured by having four essentially independent identical computer systems. Where possible each sensor also has multiple copies, usually four, and each copy feeds all four of the computer lines. If the inputs from the sensors disagree, depending on circumstances, certain averages, or a majority selection is used as the effective input. The algorithm used by each of the four computers is exactly the same, so their inputs (since each sees all copies of the sensors) are the same. Therefore at each step the results in each computer should be identical. From time to time they are compared, but because they might operate at slightly different speeds a system of stopping and waiting at specific times is instituted before each comparison is made. If one of the computers disagrees, or is too late in having its answer ready, the three which do agree are assumed to be correct and the errant computer is taken completely out of the system. If, now, another computer fails, as judged by the agreement of the other two, it is taken out of the system, and the rest of the flight canceled, and descent to the landing site is instituted, controlled by the two remaining computers. It is seen that this is a redundant system since the failure of only one computer does not affect the mission. Finally, as an extra feature of safety, there is a fifth independent computer, whose memory is loaded with only the programs of ascent and descent, and which is capable of controlling the descent if there is a failure of more than two of the computers of the main line four.

There is not enough room in the memory of the main line computers for all the programs of ascent, descent, and payload programs in flight, so the memory is loaded about four time from tapes, by the astronauts.

Because of the enormous effort required to replace the software for such an elaborate system, and for checking a new system out, no change has been made to the hardware since the system began about fifteen years ago. The actual hardware is obsolete; for example, the memories are of the old ferrite core type. It is becoming more difficult to find manufacturers to supply such old-fashioned computers reliably and of high quality. Modern computers are very much more reliable, can run much faster, simplifying circuits, and allowing more to be done, and would not require so much loading of memory, for the memories are much larger.

The software is checked very carefully in a bottom-up fashion. First, each new line of code is checked, then sections of code or modules with special functions are verified. The scope is increased step by step until the new changes are incorporated into a complete system and checked. This complete output is considered the final product, newly released. But completely independently there is an independent verification group, that takes an adversary attitude to the software development group, and tests and verifies the software as if it were a customer of the delivered product. There is additional verification in using the new programs in simulators, etc. A discovery of an error during verification testing is considered very serious, and its origin studied very carefully to avoid such mistakes in the future. Such unexpected errors have been found only about six times in all the programming and program changing (for new or altered payloads) that has been done. The principle that is followed is that all the verification is not an aspect of program safety, it is merely a test of that safety, in a non-catastrophic verification. Flight safety is to be judged solely on how well the programs do in the verification tests. A failure here generates considerable concern.

To summarize then, the computer software checking system and attitude is of the highest quality. There appears to be no process of gradually fooling oneself while degrading standards so characteristic of the Solid Rocket Booster or Space Shuttle Main Engine safety systems. To be sure, there have been recent suggestions by management to curtail such elaborate and expensive tests as being unnecessary at this late date in Shuttle history. This must be resisted for it does not appreciate the mutual subtle influences, and sources of error generated by even small changes of one part of a program on another. There are perpetual requests for changes as new payloads and new demands and modifications are suggested by the users. Changes are expensive because they require extensive testing. The proper way to save money is to curtail the number of requested changes, not the quality of testing for each.

One might add that the elaborate system could be very much improved by more modern hardware and programming techniques. Any outside competition would have all the advantages of starting over, and whether that is a good idea for NASA now should be carefully considered.

Finally, returning to the sensors and actuators of the avionics system, we find that the attitude to system failure and reliability is not nearly as good as for the computer system. For example, a difficulty was found with certain temperature sensors sometimes failing. Yet 18 months later the same sensors were still being used, still sometimes failing, until a launch had to be scrubbed because two of them failed at the same time. Even on a succeeding flight this unreliable sensor was used again. Again reaction control systems, the rocket jets used for reorienting and control in flight still are somewhat unreliable. There is considerable redundancy, but a long history of failures, none of which has yet been extensive enough to seriously affect flight. The action of the jets is checked by sensors, and, if they fail to fire the computers choose another jet to fire. But they are not designed to fail, and the problem should be solved.

Conclusions
If a reasonable launch schedule is to be maintained, engineering often cannot be done fast enough to keep up with the expectations of originally conservative certification criteria designed to guarantee a very safe vehicle. In these situations, subtly, and often with apparently logical arguments, the criteria are altered so that flights may still be certified in time. They therefore fly in a relatively unsafe condition, with a chance of failure of the order of a percent (it is difficult to be more accurate).
Official management, on the other hand, claims to believe the probability of failure is a thousand times less. One reason for this may be an attempt to assure the government of NASA perfection and success in order to ensure the supply of funds. The other may be that they sincerely believed it to be true, demonstrating an almost incredible lack of communication between themselves and their working engineers.

In any event this has had very unfortunate consequences, the most serious of which is to encourage ordinary citizens to fly in such a dangerous machine, as if it had attained the safety of an ordinary airliner. The astronauts, like test pilots, should know their risks, and we honor them for their courage. Who can doubt that McAuliffe was equally a person of great courage, who was closer to an awareness of the true risk than NASA management would have us believe?

Let us make recommendations to ensure that NASA officials deal in a world of reality in understanding technological weaknesses and imperfections well enough to be actively trying to eliminate them. They must live in reality in comparing the costs and utility of the Shuttle to other methods of entering space. And they must be realistic in making contracts, in estimating costs, and the difficulty of the projects. Only realistic flight schedules should be proposed, schedules that have a reasonable chance of being met. If in this way the government would not support them, then so be it. NASA owes it to the citizens from whom it asks support to be frank, honest, and informative, so that these citizens can make the wisest decisions for the use of their limited resources.

For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.
 

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Posted by Joe Redifer (Member # 3) on 07-30-2005, 12:38 AM:
 
I hope Phil can summarize the post above for me.
 

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Posted by Phil Hill (Member # 371) on 07-30-2005, 01:32 AM:
 
Joe, you are such an ass! Why did I have a premonition that you would pick on me for something related to Mark's long, looong, LOOONG B-O-R-I-N-G post?

While this pretty much sez it all:

quote: From Mark Gulbrandsen's quote

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For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.

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What's missing is what I originally said: Junk the manned space effort.
 

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Posted by Andy Summers (Member # 3207) on 07-30-2005, 10:28 AM:
 
I thought Joe, knew it all, Phil I’m stunned.

Only Kidding with you Joe…

Well the (EVA) today was successful, so only a few more (EVA) to go.

I wonder if NASA as a sound system like, IMAX and Lucasfilm THX.

I bet it will be totally out of this world….
 

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Posted by Mark Gulbrandsen (Member # 72) on 07-30-2005, 12:15 PM:
 
Actually NASA uses these subwoofers to do levitation testing. Really Powerful Subwoofers

Back when we ran 2001 outdoors in Lincoln Park in Chicago Servo Drive kindly donated the use of 10 of these subs. If you look at the Cinema Borealis photos in the picture warehouse the first photo shown is of the booth and some high rise apartments about 1/4 mile from where the screen was located in photos 3 and 4. We were able to rattle the glass up on the 14th floor from that distance when we had pink noise up for balancing! Apartment dwellers came down to the booth to see what was happenning and to complain. One guy brought his doberman down with him that was also obviously irritated at the noise.

They are capable of 137db spl with just 800 watts input and thay can tolerate that on a long time basis. Running ten of them at once is another story!!!!!!!!!

From a sound quality standpoint back then the subs didn't have very fast transient capability because they use an actual motor to drive the cone but thay may have gotten better since then. I wouldn't use them in a cinema situation without doing some serious listening tests. They are basically indestructable though.

Mark
 

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Posted by Andy Summers (Member # 3207) on 07-30-2005, 08:53 PM:
 
Mark,

Now this is better than school, the information you learn to expand the mind, that is one hell of a sub bass set-up and NASA has all the PhDs in the world working on these solutions.

Running ten of them, yeah, I get the picture I have a db calculator to work this out with on the pc.

Is it for sale?

I’ll buy that for a dollar…

Cheers a lot there Mark, high numbers.

 

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Posted by Mark Gulbrandsen (Member # 72) on 07-31-2005, 12:33 AM:
 
Hello Andy,

Actually if I remember corrctly back then the new price was well under 2K per woofer, not the one dollar you mentioned . In 2005 dollars though that probably at least double that 1989 price, Converted to Euro currency you might as well forget it. Too expensive for sure, alot more than a simple ride on a Russian rocket.

Now that I look at the specs the frequency sure comes down and the SPL sure goes up in a big hurry and with 10 woofers all powered up I guess I was lucky that I didn't break any windows over on those buildings. Several of those folks from that building were REALLY pissed at the noise level.

Mark
 

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Posted by Andy Summers (Member # 3207) on 08-09-2005, 09:35 AM:
 
Touchdown
http://www.astronautix.com/graphics/0/10060551.jpg

Home and safe, beautiful landing the crew will exit the shuttle after the power down of discovery is complete..

Discovery having travelled 5.8 million miles

She performed wonderfully, she a beautiful bird, they still have the right stuff and the dream is still alive….
 

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Posted by William Hooper (Member # 71) on 08-10-2005, 01:20 AM:
 
As they continue to have nightmarish problems with the tile exterior, perhaps it is time for them to consider switching to terrazzo.
 

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