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.
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.
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
That's fascinating. Can you point to any background reading on what he changed? Just better ground testing or something else?
1. yes2. Listening sites3. 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 velocity5. Different rocket and stages.6. First stage was no longer a Viking and the second stage was larger than an Aerobee.
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 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.
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.
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.
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.
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?
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.
At least one failure (TV-5) ironically appears to have been the result of over-engineering.
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?
Didn’t the Russians also use some Nazi scientists too?
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.
What were the details/goals of the RAND and FEED-BACK report?
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.
You can download the reports themselves from the RAND website.
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.
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?
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.
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).
You can download the reports themselves from the RAND website.QuoteI found Feedback I & II, but I'm not sure what the name of the 1946 report was...
I found Feedback I & II, but I'm not sure what the name of the 1946 report was...
So they simply miscalculated what they actually needed vs what they had?
Why did they stop doing this? I'm just curious as to the thought process...
That's right. They underestimated the required tank pressure levels.
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.
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.
What caused this to occur? I'm interested in the rationale as before.
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?
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.
The first three flight article Thors were lost entirely due to personnel error (dragging a LOX fill hose through sand and contaminating it,