BCal10
Topic Author
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Space Shuttle Discovery

Wed Aug 10, 2005 3:29 am

No doubt there are huge sighs of relief that Discovery is home. One question now is bugging me. Can the shuttle fly like an ordinary aircraft, ie take off from a runway. If not why not and how are they going to get it from Edwards AFB back to Florida.
 
B744F
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:31 am

They transport it on a modified 747

No it cannot "take off" like an airplane
 
Lrockeagle
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:32 am

Piggy-back it on a 747. I saw one of the shuttles come through LRAFB once years back on top of a 747. really awesome
 
BMIFlyer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:32 am

Here we go  Wink



Thanks


Lee
Sometimes You Can't Make It On Your Own
 
andz
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:37 am


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BMIFlyer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:38 am

Can you imagine the drag on that??

Must be phenomenal.



Lee
Sometimes You Can't Make It On Your Own
 
B744F
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:42 am

it really isn't much drag, the shuttle itself is designed to be very areodynamic
 
BMIFlyer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:43 am

Is N905NA an ex AA bird??



Lee
Sometimes You Can't Make It On Your Own
 
Lrockeagle
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:44 am

I guess they just lift it up with a big crane?
 
BCal10
Topic Author
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:45 am

Ok I admit I forgot about the 747. Same idea as the Buran and the An-225. Why could it not be made to fly normally like a delta wing shaped aircraft like Concorde. Is this to do with heat shield tiles and engine/rocket types?
 
cloudyapple
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:46 am

How do they put the shuttle on the back of the 747? A giant crane?
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Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:47 am

The main engines require fuel to work and that requires a large tank to be strapped to the bottom. There is no tankage for the main engines on the orbiter itself.
 
BMIFlyer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:48 am

Quoting BCal10 (Reply 9):
Why could it not be made to fly normally like a delta wing shaped aircraft like Concorde

I would just LOVE  bigthumbsup  to see the shuttle fire its rockets and zoom down the runway like an ordinary bird. VR in under 10 seconds?  Wink



Lee
Sometimes You Can't Make It On Your Own
 
Longhornmaniac
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:50 am

From the moment of the De-orbit burn which occurs roughly an hour before scheduled touchdown, to get the shuttle into the right position for reentry (a 40 degree nose up angle) and at 17,000 mph, there is no engine use. From that moment forward the shuttle becomes the most sophisticated glider ever built. To decelerate the shuttle goes through a series of left and right banks after reentry. It goes subsonic approximately 25 miles away from the landing facility and approximately 4 minutes before touchdown. From that moment, the shuttle commander (in the case of STS-114, Eileen Collins) "flies" the craft in manually. People seem to often misunderstand that they only get one shot at this. Either way, that shuttle is going to hit the ground on that pass, regardless of whether or not its on the runway. If they miscalculate by a second during their last few orbits, it'll wind up missing the runway by miles. I watched the whole thing this morning from about 3:30 CDT to touchdown. I was fascinated by it. NASA has a link to a video inside mission control with live radio communications.
Cheers,
Cameron
 
B744F
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:58 am

I was under the impression that the shuttle was fully automated
 
AsstChiefMark
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 3:58 am

Red tail...Red tail...Red tail...Red tail...Red tail...Red tail...Red tail...Red tail...Damned MSP...Red tail...Red tail
 
Longhornmaniac
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 4:02 am

Quoting B744F (Reply 14):
I was under the impression that the shuttle was fully automated

Amazingly enough...nope. You'd think something so technologically sophisticated would be, but it still needs a pilot to land.
Cheers,
Cameron
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 4:08 am

Quoting Longhornmaniac (Reply 16):
Amazingly enough...nope. You'd think something so technologically sophisticated would be, but it still needs a pilot to land.

What's the point in exhaustively screening for the best pilots only to put them on a robot?
 
BCal10
Topic Author
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 4:19 am

Thanks Longhornmaniac for the detailed description of the landing. I can see now why they they will not let it land in bad weather. If it were blown off course it it cant go around. This to seems incredibly risky. Surely small jet engines and a little fuel for a go around would have made good sense. Still no one's needed them yet.
 
andz
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 4:27 am

Quoting BMIFlyer (Reply 7):
Is N905NA an ex AA bird??


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Quoting Cloudyapple (Reply 10):
How do they put the shuttle on the back of the 747? A giant crane?


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Longhornmaniac
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 4:50 am

Quoting Glom (Reply 17):
What's the point in exhaustively screening for the best pilots only to put them on a robot?

Point Taken Glom  Smile

Quoting BCal10 (Reply 18):
Thanks Longhornmaniac for the detailed description of the landing. I can see now why they they will not let it land in bad weather. If it were blown off course it it cant go around. This to seems incredibly risky. Surely small jet engines and a little fuel for a go around would have made good sense. Still no one's needed them yet.

Haha, no problem BCal. I agree with you that its incredibly risky but one could argue that that ship doesn't need any more combustibles or explosives on it either.
Cheers,
Cameron
 
garnetpalmetto
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:00 am

Quoting Longhornmaniac (Reply 16):
Amazingly enough...nope. You'd think something so technologically sophisticated would be, but it still needs a pilot to land.

While the deorbit sequence is, I believe, automated, as pointed out earlier the mission commander pilots it on final approach. From what I remember, NASA and/or Rockwell originally planned for landing to be automated as well, but the astronauts raised a stir about the possibility of the computer lowering the landing gear too early which could have led to a potential catatastrophe. Compare that to Buran which could be flown entirely in an automated mode.
South Carolina - too small to be its own country, too big to be a mental asylum.
 
B744F
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:01 am

Quoting Glom (Reply 17):
What's the point in exhaustively screening for the best pilots only to put them on a robot?

airliners do it all the time?
 
NASOCEANA
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:02 am

Yeap! A truly awesome site to see the shuttle ferried back to Cape Canaveral on back of the modified B747. I think it will cost NASA something like $1 million to have this done.
B777 greatest Airliner ever built!
 
sean1234
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:07 am

A few Questions:

Are the Shuttle main engines not used after the center tank is dropped? I assumed smaller tanks would be inside as well.

How does the Shuttle maneuver? I observed little holes on the nose section, probably thrusters I assume. What is the power source for these thrusters/ what type of thrusters are these?

Has the shuttle ever left the orbit of the earth?

Sean
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:27 am

Quoting Sean1234 (Reply 24):
Are the Shuttle main engines not used after the center tank is dropped? I assumed smaller tanks would be inside as well.

No. There is no tankage in the orbiter itself for the SSMEs. ET jettison is performed after MECO. Initial orbit insertion at MECO is too low to be sustainable for very long because of drag. OMS maneuvers are required to raise the orbit of the orbiter to a higher level. The ET is abandoned in this low orbit and shortly it reenters and burns up.

Quoting Sean1234 (Reply 24):
How does the Shuttle maneuver? I observed little holes on the nose section, probably thrusters I assume. What is the power source for these thrusters/ what type of thrusters are these?

Those holes are the RCS thrusters, using MMH as fuel and nitrogen tetroxide as oxidiser, and can also be seen on the aft as well. They provide attitude control in space. During launch, gimballing engines provide attitude control. During reentry and aborts, the control surfaces are used. Bigger orbital maneuvers, including de-orbit is done with the OMS engines, which are two small engines which can be seen above the SSMEs.

Quoting Sean1234 (Reply 24):
Has the shuttle ever left the orbit of the earth?

No. The Space Shuttle's ceiling is fairly limited in LEO. Of course, no manned spacecraft has ever left earth orbit if you consider that the moon is still in earth orbit.

Abbreviations:
ET - External Tank
SSME - Space Shuttle Main Engine
MECO - Main Engine Cutoff
OMS - Orbital Maneuvering System
RCS - Reaction Control System
LEO - Low Earth Orbit
MMH - Monomethyl hydrazine
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:30 am

I just thought of another reason for the orbiter being unable to return itself to Complex 39 aside from the lack of propellents. The SSMEs are virtually destroyed on launch and have to be rebuilt. This Space Shuttle isn't so much reusable as repairable. This is a major reason for the poor launch rate (around 7 a year at the program's height compared to more than 25, which was intended in the program's mandate) and the high mission costs.
 
SATL382G
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:32 am

Quoting Sean1234 (Reply 24):
Are the Shuttle main engines not used after the center tank is dropped? I assumed smaller tanks would be inside as well.

No, all the fuel for the SSMEs is stored in the External Tank. Once it is jettisoned any fuel remaining in the engines or lines is purged.

Quoting Sean1234 (Reply 24):
How does the Shuttle maneuver? I observed little holes on the nose section, probably thrusters I assume. What is the power source for these thrusters/ what type of thrusters are these?

The thrusters are in 3 removable pods, one on the nose and two on the tail. The thrusters are hypergolic -- meaning no ignition system required as the fuel and oxidizer ignite on contact.

Quoting Sean1234 (Reply 24):
Has the shuttle ever left the orbit of the earth?

No, it lacks the fuel required to achieve escape velocity. Payloads launched by the shuttle have left earth orbit though.
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
SATL382G
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:36 am

Quoting Glom (Reply 26):
The SSMEs are virtually destroyed on launch

Oh yeah? You might want to rethink that or post a reference.....
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
bongo
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:44 am

Just a question: Why don't NASA launch it from Edwards AFB next time ? So they can save the transport to Fla again.
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KDTWflyer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:46 am

The entire shuttle reentry was hand flown once by a ex-marine pilot who was ready for the ultimate risk and challenge...

http://www.x-plane.com/orbiter.html
NW B744 B742 B753 B752 A333 A332 A320 A319 DC10 DC9 ARJ CRJ S340
 
SATL382G
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:52 am

Quoting Bongo (Reply 29):
Just a question: Why don't NASA launch it from Edwards AFB next time ? So they can save the transport to Fla again.

No launch pads for shuttle at Edwards....

Quoting KDTWFlyer (Reply 30):
The entire shuttle reentry was hand flown once by a ex-marine pilot who was ready for the ultimate risk and challenge...

This guy is refering to a computer game, not the real shuttle
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
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Joined: Sat Apr 23, 2005 2:38 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:52 am

Quoting Bongo (Reply 29):
Why don't NASA launch it from Edwards AFB next time ? So they can save the transport to Fla again.

Because the refurbishment and launch facilities are all at Complex 39.

Quoting SATL382G (Reply 28):
Oh yeah? You might want to rethink that or post a reference.....

Yeah. Okay, so perhaps I exaggerate with the "destroy" remark. But indeed, they can't just be restarted. I'm working on that reference for you.
 
garnetpalmetto
Posts: 5351
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 5:53 am

Quoting Bongo (Reply 29):
Why don't NASA launch it from Edwards AFB next time

No launch facility at Edwards. The original plan was for there to be an alternate launch site at Vandenberg AFB, but after the Challenger incident and the subsequent scaling back of the shuttle program, all future West Coast shuttle launches were scubbed.

Quoting SATL382G (Reply 31):
This guy is refering to a computer game, not the real shuttle

Actually, SATL, I'd point out this quote In the history of Shuttle missions (the 100th mission has just come to a close as I write this), the real space shuttle has been hand-flown for the entire re-entry only ONCE, by an ex-marine pilot, as I understand it, who was ready for the ultimate risk and challenge.

Now that is incorrect - in actuality, STS-1 through STS-4 were hand-flown re-entrys. I'd point out this article I found written by a senior handling qualities research engineer at the Dryden Research Center.

http://yarchive.net/space/shuttle/shuttle_control.html

After the first S-turn on STS-1, the entire re-entry was hand-flown
through STS-4, at which point the FCS was rewritten (and the e-seats
removed). John Young took over the flying when the sideslip meter
pegged and stayed pegged for several seconds, meaning that the limit
had been exceeded. This happened because L_YJ was about half the size
predicted and the wrong sign and not even the extremely robust FCS
could deal with that much error. Cf Iliff & Shafer, "Extraction of
Stability and Control Derivatives From Orbiter Flight Data", NASA
TM-4500, June, 1993.

Starting with STS-5, the re-entry was flown automatically by the FCS
down to just before the HAC, about Mach 1 or 2. It hasn't been
hand-flown since STS-4 and probably won't be unless the primary FCS
fails and the Orbiter is in reversionary mode or using the backup FCS.
It takes two or three (n-1, to be precise, where n is the number of
primary FCS computers) computer failures to go to a reversionary mode,
I believe, and all primary FCS computers have to fail to go to the
backup FCS.


[Edited 2005-08-09 23:03:55]
South Carolina - too small to be its own country, too big to be a mental asylum.
 
SATL382G
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:01 am

Quoting Glom (Reply 32):
But indeed, they can't just be restarted

Not in flight certainly, but they are routinely restarted on the ground without major disassembly.
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:09 am

I've got this so far. In section 3.2 it makes a vague reference to the SSMEs requiring refurbishment after every flight. I know it's not much. Let me find something else.

Ah, this might be better.
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:13 am

I've got this so far. In section 3.2 it makes a vague reference to the SSMEs requiring refurbishment after every flight. I know it's not much. Let me find something else.

Ah, this might be better.
 
SATL382G
Posts: 2679
Joined: Sat Aug 14, 2004 12:02 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:18 am

Quoting Glom (Reply 36):
I've got this so far. In section 3.2 it makes a vague reference to the SSMEs requiring refurbishment after every flight. I know it's not much. Let me find something else.

Ah, this might be better.

BIG difference between "virtually destroyed" and "requires refurbishment"
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
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Joined: Sat Apr 23, 2005 2:38 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:36 am

Quoting SATL382G (Reply 37):
BIG difference between "virtually destroyed" and "requires refurbishment"

Since I've been abandoned at Bad Astronomy, I will cede. So could they used be for a regular flight if suitable propellents were loaded?
 
SATL382G
Posts: 2679
Joined: Sat Aug 14, 2004 12:02 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 7:03 am

Quoting Garnetpalmetto (Reply 33):
After the first S-turn on STS-1, the entire re-entry was hand-flown
through STS-4, at which point the FCS was rewritten

The reentry starts well before the first roll reversal (S-turn)......

Quoting Glom (Reply 38):
So could they used be for a regular flight if suitable propellents were loaded?

If you, Glom, want to try that go right ahead.... I am merely saying that the SSMEs can be restarted without major disassembly of the engine, that it is done routinely, and that the engines are not virtually destroyed during the mission.
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 7:07 am

I already admitted to getting hyperbolic.
 
sean1234
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 8:42 am

Interesting stuff!

I need some clarification on the escape velocity. As I recall the escape velocity of the earth is about 11k/ sec. What has the shuttle accomplished when it achieves low earth orbit? Is this a partial escape, then resolving to falling around the earth at a certain point? Does the shuttle obtain escape velocity on departure at all?


Sort on a related topic. The shuttle pitches horizontal eventually on departure, why not continue a vertical profile until reaching orbit?
 
SATL382G
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 8:58 am

Quoting Sean1234 (Reply 41):
The shuttle pitches horizontal eventually on departure, why not continue a vertical profile until reaching orbit?

A vertical profile would never (at least with the amount of propellant shuttle has on board) go into orbit, it would be a very spectacular ballistic flight like SpaceShip 1 made last fall only higher.
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
MD11Engineer
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 9:28 am

Actually the Vandenberg Shuttle launch facility exists, but has never been used (be happy, American tax payers!)
In any case it could only be used for polar orbits of low altitude. The reason for choosing Cape Caneveral in first place is that it has an ocean east of it, this means that during the initial part of the flight the rocket will fly over empty ocean and not endanger anything below. The reason why you want to launch a spacecraft towards the east is that this way the roation of earth imparts a lot of speed on the spacecraft, which can be used either to lift a greater payload or to lift the same payload higher (in this aspect the European launch facility in Kourou, French Guyana, is even better, because it is closer to the equator).

In Vandenberg the only possible directions for a launch are southwards into a polar orbit, without using the roation of earth, or westwards, against the earth rotation. To the north and east are inhabited areas.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
SATL382G
Posts: 2679
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RE: Space Shuttle Discovery

Wed Aug 10, 2005 10:08 am

Quoting MD11Engineer (Reply 43):
Actually the Vandenberg Shuttle launch facility exists

The space shuttle variation of Space Launch Complex-6 (SLC-6 for short or as the locals call it Slick-6) was never completed (damn near though!) and has since been modified for other launchers. The major claim to fame for this multibillion dollar piece of only slighty used space launch infrastructure is a number of appearances in the 70s TV show "The Six Million Dollar Man".

Slick-6 was originally built for the Air Force Manned Orbiting Laboratory, a deriviative of the Gemini program, in the late 60s. When that program was cancelled the complex went into mothballs until the shuttle era. Numerous modifications were made to the complex to support Air Force shuttle operations. Discovery would have been the shuttle used from Vandenberg. After the Challenger accident the Air Force decided to launch its toys on expendable boosters and the complex went into mothballs again.

The first launcher to actually use Slick-6 was (IIRC) a Lockheed small booster based on Minuteman motors. It exploded shortly after launch.

I don't know who's using Slick-6 now but I do believe the space launch community considers it a bad omen to try and launch there...  Smile
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
Posts: 2051
Joined: Sat Apr 23, 2005 2:38 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 6:41 pm

Quoting Sean1234 (Reply 41):
What has the shuttle accomplished when it achieves low earth orbit?

The speed needed for LEO is about 8km/s.

Quoting Sean1234 (Reply 41):
Is this a partial escape, then resolving to falling around the earth at a certain point?

Not really because escape speed requires the orbit be able to go on forever without ever falling back. Not even Apollo achieved it. It simply entered into a high enough closed orbit that it could get as far as the moon, which is still in earth orbit.
 
SATL382G
Posts: 2679
Joined: Sat Aug 14, 2004 12:02 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 8:53 pm

Quoting Glom (Reply 45):
Not really because escape speed requires the orbit be able to go on forever without ever falling back

By definition an object which has achieved escape velocity from a body is no longer in orbit about that body. So if escape velocity is achieved the orbit can't go on forever because the object is no longer in orbit about that body....

http://dictionary.reference.com/search?q=escape%20velocity

Quoting Glom (Reply 45):
Not even Apollo achieved it. It simply entered into a high enough closed orbit that it could get as far as the moon, which is still in earth orbit.

Incorrect. You should check on the present location of the Apollo 8, 10, 11, and 12 S-IVBs.....

http://www.answers.com/topic/s-ivb

Glom -- you really need to check your facts before you post. Or post your opinions as opinions ("I think, I believe, IIRC, etc") and not as facts.
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
Posts: 2051
Joined: Sat Apr 23, 2005 2:38 am

RE: Space Shuttle Discovery

Wed Aug 10, 2005 10:52 pm

Quoting SATL382G (Reply 46):
By definition an object which has achieved escape velocity from a body is no longer in orbit about that body. So if escape velocity is achieved the orbit can't go on forever because the object is no longer in orbit about that body....

Astrodynamically false. An object with escape speed is in a parabolic orbit. An object with more than escape speed is in a hyperbolic orbit. These are the open orbits. That is of course in the strict two body scenario. In reality, when the sun has more influence than Earth on a body's motion, it can be said to have left earth orbit.

Check Fundamentals of Astrodynamics by Bate, White & Mueller. It's a better reference than a dictionary.

Quoting SATL382G (Reply 46):
Incorrect. You should check on the present location of the Apollo 8, 10, 11, and 12 S-IVBs.....

I'm well aware of the location of those S-IVBs.

Interesting, it appears that the TLI accelerated the Apollo 12 CSM/SLA/IU/S-IVB to a mere matter of a few m/s short of the local escape speed.

But those S-IVBs are in fact red herrings because they used gravity assist to get into solar orbit.
 
SATL382G
Posts: 2679
Joined: Sat Aug 14, 2004 12:02 am

RE: Space Shuttle Discovery

Thu Aug 11, 2005 2:05 am

Quoting Glom (Reply 47):
In reality, when the sun has more influence than Earth on a body's motion, it can be said to have left earth orbit.

It must suck when reality doesn't support your theoretical point of view...

Quoting Glom (Reply 47):
But those S-IVBs are in fact red herrings because they used gravity assist to get into solar orbit.

Why is it a red herring? You said they did not achieve escape velocity ("Not even Apollo achieved it") and they did. The means by which they did it is not in dispute here.... unless of course you want to go down that road....
"There’s nothing quite as exhilarating as being shot at and missed" --Winston Churchill
 
Glom
Posts: 2051
Joined: Sat Apr 23, 2005 2:38 am

RE: Space Shuttle Discovery

Thu Aug 11, 2005 2:25 am

Quoting SATL382G (Reply 48):
It must suck when reality doesn't support your theoretical point of view...

You said that when a body achieves escape speed, it is no longer in orbit. That is not true. It is in an open orbit. The reality bit only comes into play when the open orbit carries it sufficiently far from the attractor.

Quoting SATL382G (Reply 48):
You said they did not achieve escape velocity ("Not even Apollo achieved it") and they did.

I already admitted that the Apollo 12 TLI at least virtually achieved escape speed, which was a surprise to me.

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