What ever happened to the third Voyager spacecraft?

[Satanic Mechanic]

I am currently reading the book Voyager: Seeking Newer Worlds In The Third Great Age Of Discovery by Stephen J. Pyne.
On the second chapter, it is listed that there were three Voyager spacecraft.  The second Voyager, VGR 77-2 had flaws and it was used for spare parts for Voyager 1 (VGR 77-1) and Voyager 2 (VGR 77-3).
I tried looking up information about the whereabouts of VGR 77-2 but could not find anything.  I wondered if the full-size model at the NASM is it, but it is listed as a test model.  I am sure every scientific instrument and the RTGs were pulled off the spacecraft and reused for other spacecraft but whatever happened to it?

I was going to call it Voyager 3 but it was the second spacecraft built, so I just refer to it as VGR 77-2.

SM

[Satanic Mechanic]

This is starting to become a mystery.  I found a German website with this content translated :
http://www.raumfahrtkalender.de/thema-des-monats/august-1977
During the last months before the start of the first probe rose the doubts about the success of the mission. Over and over again defective assemblies were discovered with tests. At the beginning of August, 1977 one immediately found several anomalies in the AACS and FDS of VGR77-2. As one of three flight-certified copies same to construction of the Voyager-probe it was planned for the first start. Now, instead, VGR77-3 these roles took over, while VGR77-2, in the meantime, repaired, later than Voyager 1 flew. With the JPL one consoled himself with the wisdom that many problems signified less annoyance in use in the application with the tests as a rule. Indeed, this turned out later than mistake, however, the redundant systems could save both Voyager missions in practice over and over again.

Was it VGR 77-1 or VGR 77-2 that is Voyager 1?  This is conflicting with the book.

SM

[LunarOrbit]

I reposted your original post here and got this response from Nowhere Man:

The Magellan probe used a spare bus and main antenna left over from the Voyager program.  Don't know if they were from this "missing" craft, however.

[Satanic Mechanic]

Thanks for forwarding my question and getting back some info.  Yes, I can confirm some parts were used for Magellan.
I wonder what happened to the frame and the RTGs?  I would not be surprised if the RTGs were used in Galileo.

SM

[Satanic Mechanic]

Some news... about the RTGs.  The Voyager program was only given two RTGs, but four RTGs were built: two for the Voyager Program and two for the Lincoln Experimental Satellite program (I will have to read up on that).  The RTGs used for the interplanetary programs after Voyager were a different design that had a higher heat and electrical output.  I found this out reading a design book on RTGs.

After the two Voyagers passed their testing and were ready for launch, then they attached with the RTG. 


SM