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blackshire
01-25-2011, 11:19 PM
Hello All,

Has anyone here on YORF ever come across scale data on the Joust 1 microgravity research vehicle? This sole example of Orbital Sciences Corporation's Castor IVA-powered Prospector guided sounding rocket was launched from LC-20 (Launch Complex 20) at Cape Canaveral on June 18, 1991 (five links to photographs of and information on this vehicle are included below), and the mission failed due to a guidance system problem. Although the Prospector vehicle had three quite small fins, the design's flared conical tail section would also help to stabilize a scale model of the rocket. Here are the links:

http://www.wired4space.com/category/rockets/prospector
http://www.astronautix.com/lvs/proector.htm
http://www.skyrocket.de/space/doc_lau_fam/castor-4.htm
http://findarticles.com/p/articles/mi_pasa/is_20050229/ai_3304753905/
http://www.afspacemuseum.org/missiles/JoustI/index.htm

I hope this information will be helpful.

CPMcGraw
01-26-2011, 02:30 PM
That first pic from the AF Museum just shouts "SEMROC nose cone", doesn't it?

Have you run across any line drawings with dimensions yet? None of these links seem to have more than an overall length measurement...

jharding58
01-26-2011, 03:17 PM
This gemtleman was the PM for Joust out of University of Alabama Huntsville.

http://www.eng.uah.edu/~wesslif/resume.html

Perhaps he might be amenable to providing some assistance on an underdocumented subject? Course, that was quite a while ago.

jharding58
01-26-2011, 03:27 PM
If only Peter had been able to finish up all that he wanted to do...

http://groups.yahoo.com/group/scaleroc/message/5584

blackshire
01-27-2011, 12:34 AM
That first pic from the AF Museum just shouts "SEMROC nose cone", doesn't it?

Have you run across any line drawings with dimensions yet? None of these links seem to have more than an overall length measurement...Unfortunately, no. I've sent an e-mail message to OSC's launch vehicle department--hopefully they have dimensioned drawings (or at least vehicle section dimensions lists).

blackshire
01-27-2011, 12:38 AM
This gemtleman was the PM for Joust out of University of Alabama Huntsville.

http://www.eng.uah.edu/~wesslif/resume.html

Perhaps he might be amenable to providing some assistance on an underdocumented subject? Course, that was quite a while ago.I also miss Peter's previously-growing scale data packs. Thank you for posting Dr. Wessling's resume web page! I'll contact him to see what he might have on Joust 1.

jharding58
01-31-2011, 04:25 PM
Attached a pdf with dimension and station. Courtesy of Professor Wessling

blackshire
01-31-2011, 06:45 PM
Attached a pdf with dimension and station. Courtesy of Professor WesslingWhat an excellent find--thank you very much for posting this! Just to clarify, this drawing looks (from its style) like it's from one of the NASA "blue books" (stapled-together sounding rocket mission profile/plan booklets with blue front and back covers, which were distributed to project personnel--I saw many of these when I was the volunteer historian at Alaska's Poker Flat Research Range www.pfrr.alaska.edu ). The vehicle drawings in these "blue books" are rather schematic in character; that is, every detail isn't 100% accurate, but that does *not* make the "blue book" drawings any less useful for scale modeling purposes (please see below).

For example, the Joust-1 vehicle had "pure" delta fins, but the fins shown in the "blue book" drawing are of clipped delta planform. Also, the rocket's payload section was slightly wider than the Castor IVA rocket motor, but this diameter difference isn't shown in the "blue book" drawing. The station numbers (the distances from the nose tip to various component interface planes) are invaluable--used in concert with vehicle photographs, they enable modelers to build high-fidelity miniature replicas of the full-scale rockets that considerably exceed the minimum Sport Scale documentation requirements. Also:

This drawing indicates that the bottom end of the Joust-1 payload was fitted with a spherical-section re-entry heat shield (similar in shape to the Mercury and Gemini capsules' heat shields). It looks like an arrow indicating the heat shield's radius of curvature is pointing to it, but the number is off the edge of the page. (This dimension isn't necessary to build a good Sport Scale model of the Joust-1 vehicle, but one intended to garner more Flight Points with a separately-recovered payload would do well to have an accurately-shaped heat shield.)

jharding58
01-31-2011, 07:23 PM
Did not get an indication as to the source but I would assume that to some degree the general layout is consistent with the vehicles.. The zero station appears to be above the radius of the NC so I imagine that generating a Nose cone scaled to a BT-55 woudl be relatively easy to do. This was the sole content I received from Professor Wessling so I am not going to look a gift horse. As for the fin shape I cannot tell if it is a slab with triangular LE or if this is a diamond fin. The Castor flew with both.

As for the general dimensions from the stations they seem to tally with the Astronautix specifications of 46.2 ft and 3.3ft for the airframe diameter. The frustum around the engine bell seems to look right, and I suppose you squint the length of the tubular section at the very base from the drawing.

I agree that this is rather more of a representation than a scale crawing, but to your point, the MR drawings that I cadged from Bluebooks were close enough.

CPMcGraw
02-01-2011, 10:34 AM
Try using ST-20 instead... :)

If you take that base diameter of 40" as a starting reference, dividing by 20 (making this a 1:20 scale model) gives you 2", which is so very close to ST-20's 2.04".

Using that 1:20 as a guide, the lower section of the transition becomes 2.8", and that is very close to LT-275 at 2.84"...

Attached is an early RS "sketch", with no serious internal structure for engines or recovery systems. It's just an outline. It also doesn't take into account the larger diameter of the payload section...

blackshire
02-01-2011, 11:24 AM
Craig, although the fins in your drawings don't reflect the Joust-1 vehicle's actual "pure delta" fins (a good close-up, pre-launch photograph of Joust-1 is attached below), those clipped-delta fins from the NASA "blue book" Joust-1 drawing *are* (I'm pretty sure) accurately representative of the upper-stage fins of OSC's two-stage (Talos-Sergeant) Starbird vehicle.

CPMcGraw
02-01-2011, 11:56 AM
As I worked on the sketch, I could see there were differences in the outline versus the final vehicle. The nose cone is another obvious inconsistency. The outline shows a blunt tip (rounded), while the final flight configuration had a full sharp-tipped conical.

What I suspect is the outline represents the base vehicle (Castor), and thus is good for getting the length and transition sections of the boost module. Those portions would be 'locked' to the developers, as it was a COTS (Commercial Off The Shelf) item. Fins could be changed, as could the final payload, but not so much the motor section.

I did look at that photo after putting the sketch together. With a bit more refining, we should have something closer to the actual shape soon. :D

blackshire
02-01-2011, 01:10 PM
I agree--I think they "refined" (reduced the size of, and changed the shape of) the Joust-1's movable steering fins from the Starbird upper stage (which required more "control authority" than Joust-1 because the Starbird had longer and heavier payloads, plus a massive Talos first stage).