Author Topic: Project Orbiter / Vanguard  (Read 17322 times)

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #20 on: 12/07/2018 08:23 pm »
The terrific thing about Vanguard was that it brought together a solid team at NRL (Milton Rosen, etc.) who oversaw the creation of the world-wide tracking system, the launch site, and especially the ultimately uber-reliable, pressure-fed, three-axis control (during coasts) with guidance-system second stage.  That group, much of it, became NASA's Goddard Space Center.  That stage became the second stage of Thor-Delta, by-far NASA's most reliable launch vehicle of its time (Rosen coined the "Delta" name).  The Aerojet propulsion system spawned by that stage went on, after many iterations and upgrades, to serve as the ancestor for generations of Delta second stages, for the Titan Transtage, for some of Japan's N-series "Delta" upper stages, for the Space Shuttle OMS, and someday maybe soon, for Orion.  Not a bad legacy.

More immediately, the second stage was used on Thor-Able and (unfortunately) Atlas-Able.  It became reliable later on, but getting it to work in the early days was tough. Despite two dramatic first stage malfunctions, the second stage was responsible for almost all Vanguard flight failures. The causes were varied, but mostly related to the learning curve at this early stage. At least one failure (TV-5) ironically appears to have been the result of over-engineering. In the end, only three of eleven Vanguard launches were fully successful. But yes, the stage kept on going, evolving, and getting bigger and more powerful with time.

It is also probably correct that Martin lost interest in Vanguard as soon as they got the Titan I contract, although in all fairness they didn't display a whole lot of motivation with that either since it was merely a backup ICBM to Atlas.

Thor-Able onward also used an uprated solid third stage, this was also flown on the final Vanguard launch.

« Last Edit: 12/08/2018 03:46 am by WallE »

Offline yoram

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Re: Project Orbiter / Vanguard
« Reply #21 on: 12/08/2018 05:27 am »
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For the Soviet program, this wasn't until the mid-70s when Valentin Glushko was put in charge of the entire effort and mission success rates improved a lot.

That's fascinating. Can you point to any background reading on what he changed? Just better ground testing or something else?

Offline rickl

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Re: Project Orbiter / Vanguard
« Reply #22 on: 12/08/2018 06:13 am »
I highly recommend the official NASA Project Vanguard history (SP-4202) by Constance McLaughlin Green and Milton Lomask.  Here it is:  https://history.nasa.gov/SP-4202.pdf 


I haven't read that, but I have "The Viking Rocket Story" by Milton Rosen and "Project Vanguard" by Kurt R. Stehling, both in hardcover.  They're out of print but can be found on used book sites.  I recommend them both.


This is probably off-topic, but I can't help noticing that Rocket Lab's Electron rocket is roughly comparable to the size and liftoff thrust of Vanguard.  Of course, Electron is much more efficient and capable.
The Space Age is just starting to get interesting.

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #23 on: 12/08/2018 08:02 am »
That's fascinating. Can you point to any background reading on what he changed? Just better ground testing or something else?

After the Kremlin cancelled the manned lunar program in 1974, they consolidated the entire space program into a single body run by Glushko, who headed it until his death in the late '80s. One of the perennial handicaps of the Soviet program had always been endless squabbles between different design bureaus, all of who distrusted and plotted against each other. A lot of it was related to ancient resentments left over from the Stalin purges--in particular, Korolev had it in for Glushko for denouncing him to the NKVD.

The ASTP program and detente policies in the '70s also gave the Soviets increased access to American industrial and managerial knowledge which helped improve the overall organization and Q/C of the space program and eliminating practices such as testing rocket engines with military acceptance test methods (big reason for the N-1's failure).

After the program was consolidated, Glushko's first act was to cancel N-1 and begin development of a new HLV that eventually became Energia (also they built proper static firing facilities for it the lack of which doomed N-1). It may well be pointed out with some irony that another reason for N-1's failure was Glushko's refusal to believe that LH2 was a viable rocket propellant despite the protests that it was already being used by the US program on Centaur. Only after the Apollo program was he finally converted. Also worth noting that Werner von Braun distrusted LH2 and it was hard to convince him of the necessity of LH2 stages for Saturn rather than some of the more silly ideas he had at the time such as a Saturn-Agena (imagine how ridiculous that would have looked).

Out of this also came Zenit, although Soviet manufacturing still could not conquer combustion instability in large kerolox engines, so they were forced to use four smaller combustion chambers in the RD-171.

All things considered, the last 15 years of the Soviet space program showed considerable growth and maturity even if some unavoidable handicaps  still existed (the Tselina disaster at Plesetsk in 1980 being one of the uglier reminders of how personnel safety was still weak compared with the US program).

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #24 on: 12/09/2018 12:04 am »
1. yes
2.  Listening sites
3.  NRL is not part of the fleet.  It is part of the Office of Naval Research in the Secretariat of the Navy.
4.  Just need more velocity
5.  Different rocket and stages.
6.  First stage was no longer a Viking and the second stage was larger than an Aerobee.
1. The prospect of the USSR setting their airspace to infinity would have been a major problem, I assume we'd have done the same and it'd made the prospect of nuclear war just that much greater.

2. By listening sites, I assume you mean more than just tracking the movement of the rocket, but listening to transmissions made by the rocket?

4. When you say more velocity -- how much?  And what caused them to miscalculate the amount of energy required to achieve orbit?

5. So basically they redesigned the first stage and stretched the second rocket stage?


The USAF satellite program had a number of milestones. You could argue that it began in 1946 with the RAND report, and then some experiments in the late 1940s and early 1950s, followed by the very important FEED BACK report.
What were the details/goals of the RAND and FEED-BACK report?

With so many sounding-rockets designs being developed and launched through this period, what experiments were carried out and with what programs?

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I think that the USAF program became a program in 1954 at Wright-Pat and moved to Los Angeles in 1955, but I don't think that the contract award to Lockheed happened until 1956 (that was first named Sentry, then renamed Samos). What became CORONA was not proposed until 1957 and did not get approved until early 1958. But I'm being too lazy to look this stuff up in my own books.
Rare you get to write to an author, I’ve done it once or twice before.  What books did you write?

With Project Orbiter starting in 1954, and the Vanguard program being initiated in 1955, this would be roughly at the same time as the start of the Orbiter program.  I’m curious if the reason they took so much longer to have a workable design was because the previous two programs were launched after they had a proposal?
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The best overall source on this is going to be Mike Neufeld's biography on von Braun. Ancillary materials include several articles and book chapters written by me and a few others concerning "freedom of space," but Neufeld really has the most recent close examination of the subject.

What Neufeld has pointed out is that Vanguard's technology was significantly better than Orbiter's technology--particularly the electronics--and that hurt the Orbiter proposal. There was some real doubt that even if Orbiter had worked, it might not be possible to detect the satellite in orbit. What Neufeld has said publicly is that it is important to understand that Explorer 1 was not Orbiter--Explorer 1 was a more capable and better design. Orbiter was rather primitive.
I actually thought Explorer 1 was basically Orbiter’s proposal simply revived and rushed into operation after Sputnik was launched into space: How did the designs differ in terms of size and mass, and technological advantages (what isn’t secret anyway).
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It is easy to forget it these days, but NRL was a world leader in electronics in the 1940s and 1950s (and even later, although that gets into some still-classified stuff). They put together a very good proposal and they most likely won on the basis of that proposal.

Also, you see in this first major spaceflight decision by the United States many of the same themes that have existed throughout the space program and indeed exist even on this board when it comes to perception over reality. People look back at this decision and think that the Army had the better rocket and that rockets are the most important thing. But there's a lot more to a space program than the rocket. There's the spacecraft, the electronics, and there's the ground processing (and tracking). What the DoD review panel was looking at back then was the entire package, not just the rocket, but what everybody seems to pay attention to is the rocket.
This might reflect ignorance, but I’m curious why they create a civilian-run program that would be dedicated to space-flight and just create a “dream team” — just take the best of each and make sure the person leading it had the means to reign in everybody?

I checked the definition of IGY: It seems to be the period from 7/1/57 to 12/31/58


In my opinion Von Braun's ties to Nazi party were the most significant reason.  Imagine the historical significance of an ex Nazi party member the head of the 1st satellite.  The fact that the Russians did it first and all the hysteria that followed, cleared the decks so to speak for Von Braun's future involvement in the US space program.
Didn’t the Russians also use some Nazi scientists too?
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I wonder sometimes how much the space race history would have changed had we put the 1st satellite up?  For example the justification for the Apollo program for landing a man on the moon was it was a space feat that we thought we could beat the Russians at.  Had we already beaten the Russians at the 1st satellite, would the tremendous cost of project Apollo still have been justified?
I figure we’d probably still have had reasons to do it, even if it was simply to put missile launchers in orbit. 

Ed Kyle makes a valid point though that even if we went first, regardless we would have been able to rationalize the fact that they had a bigger satellite because we were the first to do it — the first person to do it always has the hardest time.

Admittedly the Cold War was, arguably, the biggest and most expensive game of one-upsmanship in the history of the entire world (though with inflation these days…)


More immediately, the second stage was used on Thor-Able and (unfortunately) Atlas-Able.  It became reliable later on, but getting it to work in the early days was tough. Despite two dramatic first stage malfunctions, the second stage was responsible for almost all Vanguard flight failures.
Is there any place where one could go to find an accurate list of the various things that happened to these flights?
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At least one failure (TV-5) ironically appears to have been the result of over-engineering.
How so?
« Last Edit: 12/09/2018 12:05 am by Zipper730 »

Offline thammond

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Re: Project Orbiter / Vanguard
« Reply #25 on: 12/09/2018 01:03 am »
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2. By listening sites, I assume you mean more than just tracking the movement of the rocket, but listening to transmissions made by the rocket?

Yes the minitrack system was used to communicate with the satellite as well as track it.  The satellite had scientific instruments on board and needed to send that data back to earth to be of any benefit.

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4. When you say more velocity -- how much?  And what caused them to miscalculate the amount of energy required to achieve orbit?

The velocity of a satellite varies depending on the orbit its in, but a round figure for the necessary velocity to achieve orbit is 17,000 MPH.  I don't think anyone on the Vanguard project "miscalculated" it if that is what you mean.  Some of the Vanguards did achieve orbit.  The ones that didn't were due to malfunctions in the rocket, not miscalculations.

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Didn’t the Russians also use some Nazi scientists too?

Yes the Russians did use Germans also.  We got the best and brightest of the lot though.  Also the Germans played vastly different roles in the US and Russian rocket programs.  In the US they played a major role for many years.  In Russia they were pushed aside as soon as the Russian rocket scientists got up to speed.  Furthermore in Russia no one would have known as there rocket scientist identities were kept top secret.

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Ed Kyle makes a valid point though that even if we went first, regardless we would have been able to rationalize the fact that they had a bigger satellite because we were the first to do it — the first person to do it always has the hardest time.

Maybe or maybe not.  I think the US started to have 2nd thoughts about the Apollo program due to the enormous costs involved.  Kennedy even offered at one point to join forces with the Russians on the moon project.  We started significant budget cuts in the space program before the first Saturn V rocket ever flew.  There were two items that kept our nose to the grindstone so to speak.  One was that Russia had all the 1st's in space milestones, and the 2nd was Kennedy's assassination (no one had the will to kill the program Kennedy started).

 


Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #26 on: 12/09/2018 04:55 am »
If you want to know the specifics of each Vanguard flight, here goes:

TV-3: Low tank pressure caused burning propellant to back up into the injector head and destroy it. This caused a shock wave that ruptured a fuel line, causing loss of thrust and pad fallback. Tank pressures were increased on subsequent flights.

TV-3B: Improper pitch signals caused the booster to pitch 40° at T+55 seconds. The second stage broke in half from aerodynamic loads. The Range Safety destruct command was sent to the first stage at T+60 seconds.

TV-4: Orbited Vanguard 1.

TV-5: The arming command was not sent to the third stage, preventing it from starting. This was caused by the failure of a relay designed to make sure that helium was pumped to the second stage attitude control jets during coasting. The relay was deemed unnecessary and removed from subsequent vehicles (thus your over-engineering).

SLV-1: A transient in the pitch plane at third stage separation resulted in an incorrect attitude reference for the flight control system. The second stage pitched up 63° and sent the third stage and satellite on a high arcing trajectory before it came down and reentered off the coast of South Africa. The transient was deemed to be the result of high frequency combustion instability in the second stage engine at shutdown, which ruptured the thrust chamber and caused a shock.

SLV-2: The second stage engine shut down after only 8 seconds of operation and orbit was not achieved. It was believed that scale from the oxidizer tank had plugged up the propellant feed system.

SLV-3: The second stage operated at only 80% thrust. The third stage and payload managed a single orbit before reentering over Africa. It was believed that particles shed from a rubber fill hose had clogged the propellant feed system, causing fuel starvation to the engine. The hose was changed to metal, heat treating used to remove scale buildup in the propellant tanks, and preflight procedures modified to reduce the need to open up the propulsion system and contaminate it.

SLV-4: Orbited Vanguard 2.

SLV-5: A delay of 0.9 seconds in first stage separation caused the second stage to start while still attached to it. Exhaust gases from the engine pushed the thrust chamber to the limit of the gimbal stops and broke them, resulting in complete loss of control. The second stage cartwheeled and the third stage and satellite broke away, impacting in the Atlantic Ocean some 300 miles downrange.

SLV-6: The second stage helium control bottle valve failed to open at engine start, causing loss of tank pressure and engine thrust, which gradually decayed and became unstable. After 40 seconds of engine operation, the helium bottle ruptured from pressure buildup. Third stage separation and ignition were accomplished, but the incorrect flight vector sent it into the drink rather than orbit.

SLV-7: Orbited Vanguard 3.

Offline Proponent

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Re: Project Orbiter / Vanguard
« Reply #27 on: 12/09/2018 03:48 pm »
What were the details/goals of the RAND and FEED-BACK report?

You can download the reports themselves from the RAND website.
« Last Edit: 12/09/2018 03:48 pm by Proponent »

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #28 on: 12/11/2018 04:15 am »
Thammond
Reply #25

1. What kind of scientific equipment did Vanguard’s satellite carry onboard?
2. I thought you needed a different trajectory to get into orbit than produce a ballistic trajectory?
3. Why did the Russians quickly move German scientists to the periphery after their own scientists were brought up to speed?
4. Another reason a program like Saturn could be kept alive would be for putting weapon systems in space or on the Moon.  I’m not a big fan of this practice, but there were proposals such as the Lenticular Re-entry Vehicle that would have involved controlling and launching missiles from space and being able to re-enter the atmosphere and be re-used.


WallE
Reply #27

Quote
If you want to know the specifics of each Vanguard flight, here goes:

TV-3: Low tank pressure caused burning propellant to back up into the injector head and destroy it. This caused a shock wave that ruptured a fuel line, causing loss of thrust and pad fallback. Tank pressures were increased on subsequent flights.

TV-3B: Improper pitch signals caused the booster to pitch 40° at T+55 seconds. The second stage broke in half from aerodynamic loads. The Range Safety destruct command was sent to the first stage at T+60 seconds.

TV-4: Orbited Vanguard 1.

TV-5: The arming command was not sent to the third stage, preventing it from starting. This was caused by the failure of a relay designed to make sure that helium was pumped to the second stage attitude control jets during coasting. The relay was deemed unnecessary and removed from subsequent vehicles (thus your over-engineering).

SLV-1: A transient in the pitch plane at third stage separation resulted in an incorrect attitude reference for the flight control system. The second stage pitched up 63° and sent the third stage and satellite on a high arcing trajectory before it came down and reentered off the coast of South Africa. The transient was deemed to be the result of high frequency combustion instability in the second stage engine at shutdown, which ruptured the thrust chamber and caused a shock.

SLV-2: The second stage engine shut down after only 8 seconds of operation and orbit was not achieved. It was believed that scale from the oxidizer tank had plugged up the propellant feed system.

SLV-3: The second stage operated at only 80% thrust. The third stage and payload managed a single orbit before reentering over Africa. It was believed that particles shed from a rubber fill hose had clogged the propellant feed system, causing fuel starvation to the engine. The hose was changed to metal, heat treating used to remove scale buildup in the propellant tanks, and preflight procedures modified to reduce the need to open up the propulsion system and contaminate it.

SLV-4: Orbited Vanguard 2.

SLV-5: A delay of 0.9 seconds in first stage separation caused the second stage to start while still attached to it. Exhaust gases from the engine pushed the thrust chamber to the limit of the gimbal stops and broke them, resulting in complete loss of control. The second stage cartwheeled and the third stage and satellite broke away, impacting in the Atlantic Ocean some 300 miles downrange.

SLV-6: The second stage helium control bottle valve failed to open at engine start, causing loss of tank pressure and engine thrust, which gradually decayed and became unstable. After 40 seconds of engine operation, the helium bottle ruptured from pressure buildup. Third stage separation and ignition were accomplished, but the incorrect flight vector sent it into the drink rather than orbit.

SLV-7: Orbited Vanguard 3.

TV-3: While this might sound silly, why was the tank pressure low?
TV-5: So if if the relay didn’t sense helium was being pumped to the second stage attitude control jets during the coast, it would not arm the third stage?  Why did they use this design feature?


Proponent
Reply #28

Quote
You can download the reports themselves from the RAND website.
I found Feedback I & II, but I'm not sure what the name of the 1946 report was...
« Last Edit: 12/11/2018 04:29 am by Zipper730 »

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #29 on: 12/11/2018 04:18 am »
Sheesh, when you embed multiple quotes from multiple people in a single post do you really expect them to reply? I'm not going to dig out the specific quotes to respond to when it's just a giant plate of spaghetti.
I don't want my text to be illegible, would it be okay if I simply quoted the things you said, and placed something that indicated it was from Reply 20 or 25 or something?

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #30 on: 12/11/2018 06:39 am »
TV-3: While this might sound silly, why was the tank pressure low?

The tank pressure was on spec, but it turned out that they needed to make it slightly higher to prevent this failure mode from happening again.

TV-5: So if if the relay didn’t sense helium was being pumped to the second stage attitude control jets during the coast, it would not arm the third stage?  Why did they use this design feature?

No the relay was supposed to open a bypass valve to allow greater flow of helium to the attitude control jets. You are correct that the third stage arming command was not sent because it failed to activate. Ground testing found that this relay was not necessary to ensure sufficient helium flow to the attitude control jets and it was thus removed.

After the second stage difficulties encountered on TV-5, SLV-1, and SLV-2, it was decided to reinstate static firing tests of the second stage, which had only been done on TV-3 and 3-BU (too bad the poor things never got a chance to actually operate in flight). They static-fired SLV-3's second stage, but the exhaust gases shoved the thrust chamber around violently and ended up breaking the gimbal acutators. After this, they decided to ship the second stage engines back to Aerojet for inspection/cleaning etc rather than attempt to static fire them.

Remember that this was very early in the space program and everyone was still learning.
« Last Edit: 12/11/2018 07:40 am by WallE »

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #31 on: 12/11/2018 07:45 am »
The tank pressure was on spec, but it turned out that they needed to make it slightly higher to prevent this failure mode from happening again.
So they simply miscalculated what they actually needed vs what they had?
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No the relay was supposed to open a bypass valve to allow greater flow of helium to the attitude control jets. You are correct that the third stage arming command was not sent because it failed to activate. Ground testing found that this relay was not necessary to ensure sufficient helium flow to the attitude control jets and it was thus removed.

After the second stage difficulties encountered on TV-5, SLV-1, and SLV-2, it was decided to reinstate static firing tests of the second stage, which had only been done on TV-3 and 3-BU (too bad the poor things never got a chance to actually operate in flight).
Why did they stop doing this?  I'm just curious as to the thought process...

Offline Proponent

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Re: Project Orbiter / Vanguard
« Reply #32 on: 12/11/2018 08:17 am »
You can download the reports themselves from the RAND website.
Quote
I found Feedback I & II, but I'm not sure what the name of the 1946 report was...

Look for "World-circling Spaceship," if I remember correctly.  Or just browse reports in the mid-1940's -- there are not many.
« Last Edit: 12/11/2018 06:33 pm by Proponent »

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #33 on: 12/11/2018 10:38 pm »
So they simply miscalculated what they actually needed vs what they had?

That's right. They underestimated the required tank pressure levels.

Why did they stop doing this?  I'm just curious as to the thought process...

Giving the second stage a pre-flight readiness firing added an additional three weeks to the preparation time for the launch. The first stage could be test-fired on the pad, but the second stage had to be taken down, put in a separate test firing stand, and then the launch vehicle reassembled. So they decided to just skip it after the first two Vanguard launches.

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #34 on: 12/12/2018 01:49 am »
That's right. They underestimated the required tank pressure levels.
What caused this to occur?  I'm interested in the rationale as before...

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Why did they stop doing this?  I'm just curious as to the thought process...

Quote
Giving the second stage a pre-flight readiness firing added an additional three weeks to the preparation time for the launch. The first stage could be test-fired on the pad, but the second stage had to be taken down, put in a separate test firing stand, and then the launch vehicle reassembled. So they decided to just skip it after the first two Vanguard launches.
So the issue was keeping things within a reasonable time-table: I'm curious how long it would take to test fire on the pad; then attack the upper stages?  I'm also curious why they would need to take down the second stage when test firing the first -- isn't the whole assembly designed to fly as an organic whole?

Offline Zipper730

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Re: Project Orbiter / Vanguard
« Reply #35 on: 12/12/2018 02:02 am »
Blackstar
Reply #8

Quote
I guess that requires a lot more clarification. The USAF satellite program had a number of milestones. You could argue that it began in 1946 with the RAND report, and then some experiments in the late 1940s and early 1950s, followed by the very important FEED BACK report. I would have to look it up, but I think that the USAF program became a program in 1954 at Wright-Pat and moved to Los Angeles in 1955, but I don't think that the contract award to Lockheed happened until 1956 (that was first named Sentry, then renamed Samos). What became CORONA was not proposed until 1957 and did not get approved until early 1958. But I'm being too lazy to look this stuff up in my own books.

1. Was the 1946 RAND report titled "World Series" or "World Circling Spaceship"?
2. What kind of rocket programs was the USAF working on?  There were so many sounding-rocket developments -- it's hard to keep track of what was going on when...
3. It seems that the USAF's rocket ideas kind of began to gel after from 1946-1954: With Project Orbiter starting in 1954, and the Vanguard program being initiated in 1955, this would be roughly at the same time as the start of the Orbiter program.  I’m curious if the reason they took so much longer to have a workable design was because the previous two programs were launched after they had a proposal?
4. What books did you write?
« Last Edit: 12/12/2018 02:03 am by Zipper730 »

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #36 on: 12/12/2018 05:50 am »

What caused this to occur?  I'm interested in the rationale as before.

No reason in particular other than lack of experience by the launch crews. In 1957, only Von Braun's team at ABMA had a lot of experience with ballistic missiles. You can see how Jupiter did much better in its test program than other vehicles, while the Douglas, Martin, and GD/A people didn't really know what they were doing yet. It took a lot of flight failures to learn why a particular preflight procedure had to be revised or a certain missile component had design flaws that needed to be fixed.

Actually one of Von Braun's guys once said "I've always preferred failures to a successful launch. After all, you don't learn anything from a successful one."

So the issue was keeping things within a reasonable time-table
That would be correct.

I'm curious how long it would take to test fire on the pad; then attack the upper stages?  I'm also curious why they would need to take down the second stage when test firing the first -- isn't the whole assembly designed to fly as an organic whole?

Since when would you have to remove the second stage to PFRF the first stage? Obviously you wouldn't need to take it down for that, you just have the whole vehicle set up and run the first stage engine on the pad for a while (not sure exactly how long though). They had to disassemble the vehicle so the second stage could be static fired, and then the whole stack reassembled. This took an additional three weeks of work which was why it was dropped after the first two Vanguard launches.
« Last Edit: 12/12/2018 09:47 am by WallE »

Offline Blackstar

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Re: Project Orbiter / Vanguard
« Reply #37 on: 12/12/2018 12:19 pm »
No reason in particular other than lack of experience by the launch crews. In 1957, only Von Braun's team at ABMA had a lot of experience with ballistic missiles. You can see how Jupiter did much better in its test program than other vehicles, while the Douglas, Martin, and GD/A people didn't really know what they were doing yet. It took a lot of flight failures to learn why a particular preflight procedure had to be revised or a certain missile component had design flaws that needed to be fixed.

It took a long time, and of course after they solved the easy things that caused the rockets to blow up, they started encountering very complex and subtle things that caused the rockets to blow up:

http://www.thespacereview.com/article/1333/1

"Within the program office in Los Angeles, this became known as the “Lesson of 1019,” often shortened to “1019.” All Battle or anyone had to do was say “1019” and everyone knew what they meant—check to make sure that nothing has been missed, that doing one thing will not cause something else to go wrong. Emphasize “systems integration” so that all of the complex parts of a spacecraft will work properly together. Quality control was vital and required constant vigilance. When the Lockheed engineers took the vehicle apart back in the factory, they found a number of flaws that would have prevented it from ever reaching orbit."


And:

http://www.thespacereview.com/archive/1333.pdf

« Last Edit: 12/12/2018 12:24 pm by Blackstar »

Offline WallE

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Re: Project Orbiter / Vanguard
« Reply #38 on: 12/13/2018 05:05 am »
Interesting and you can see how the points raised in that document occurred at some point or another:

*Unfixed troubles will bite you again
There were a lot of flight failures in the early days that were needlessly repeated because the Air Force tried to rush launch schedules and didn't want to take the time to fix something even after the engineers knew what was wrong. Most famously the turbopump problems that ABMA quickly moved to fix on Jupiter, but the Air Force couldn't be bothered and so several more Thors and Atlases were lost before they finally accepted reality.

*Personnel mistakes are far more common than design flaws
Design flaws are usually weeded out in the first couple of R&D flights of a vehicle. After that it's mostly just mistakes made installing or repairing or fabricating some component. The first three flight article Thors were lost entirely due to personnel error (dragging a LOX fill hose through sand and contaminating it, wiring a Range Safety console incorrectly, and not paying attention to a pressure warning). Numerous Thor and Atlas DoD space launches from the West Coast were also lost due to careless mistakes.

*System integration is very important
This caused the loss of Mercury-Atlas 1 and all three Atlas-Able launches. Improper system integration also caused the slightly bizarre failure of Atlas 19F/NOAA-B twenty years later.



Offline Jim

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Re: Project Orbiter / Vanguard
« Reply #39 on: 12/14/2018 11:34 am »
The first three flight article Thors were lost entirely due to personnel error (dragging a LOX fill hose through sand and contaminating it,

Not true.  There is a difference between process mistakes and errors.  Dragging the LOX hose through sand was something that could be done with RP-1 or aircraft refueling. 

The mis-wired range safety console was a range problem and could have happened on any launch.

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