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View Full Version : NASA Study Summary: "Evaluation of JPL 4 Stage Solid Nova Vehicle"


luke strawwalker
04-10-2011, 06:16 PM
Here's a study critiquing the JPL All-solid fuel four stage NOVA vehicle concept and refining the ideas related to vehicle structures requirements and supporting infrastructure (launch pads and ground handling). Most of the graphics used in the presentation are identical or similar in nature to the ones previously posted in the JPL Four Stage Solid NOVA Vehicle Study Summary posted here earlier. Some new relevant graphics are included here relating to the aerodynamic interstage fairings for the vehicle and some historically interesting concepts related to the vehicle assembly and launch mode comparisons studied.

Enjoy! OL JR

luke strawwalker
04-10-2011, 06:18 PM
Several different areas of focus in this study, refining and critiquing the earlier JPL NOVA study, was on aero-fairings, interstages, and various other vehicle structures. Usually at least two proposals for each interstage are given and compared and contrasted-- no definitive 'downselect' or recommendation of one particular design over the others were given. Each diagram contains a caption describing the interstage to which it refers (stage1/stage2, or stage 2/stage 3, or stage 3/4). The proposals are pretty self explanatory and the diagrams should help anyone wishing to construct a model of this vehicle to construct the interstage aero-fairing they find most logical or aesthetically pleasing...

More to come! OL JR

luke strawwalker
04-10-2011, 06:20 PM
These pics address another concern totally glossed over in the original JPL proposal-- supporting the vehicle on the launch pad... JPL erroneously assumed that the most desirable and efficient way to join the SRMs together into stage assemblies and support the vehicle's weight on the pad was through "scarring" the SRMs by welding mounts and weight supporting pads directly to the SRM steel casings themselves. STL's assessment from Minuteman development was that this induces severe localized strain and deformations into the casings, which as pressure vessels should not be compromised by unanticipated outside forces or loadings that could cause case failure in operation. Their recommendations were that for interstages and launch pad support, that fwd/aft skirts be attached to the SRM motor casings and then the interstage or vehicle weight be supported through these skirts spreading the forces equally to the casings, rather than through localized brackets or scarring... Hence the need for an 'aft skirt' to support the 35 million pounds of loaded rocket on the launch pad, either through a straight cylindrical section design, or a 'scalloped' design using an inverted "V" truss structure integrated with an aero-fairing.

More to come... OL JR

luke strawwalker
04-10-2011, 06:21 PM
These last two pics relate to the proposed methods of assembling the vehicle on the launch pad... Obviously this is going to have to be done in-situ-- moving the 35 million pound assembly once constructed other than under it's own power in flight simply wasn't possible, so it had to rely on 'stack on the pad' methods. Two different modes were proposed...

Later! OL JR

luke strawwalker
04-15-2011, 10:20 AM
Here's another critique of the JPL four stage solid NOVA vehicle that I've summarized... much of the material is in the other studies, so I've decided to attach this directly to this study rather than start a new thread. There are some interesting ideas about using the first two SRM first stages to lift hydrogen-powered upper stages to give MUCH better performance, even making a Mars mission possible...

Here's the study summary and a couple of new pics that went along with it...

The first pic is a comparison of some of the previous NOVA studies, including a side-by-side of the JPL solid NOVA with the Grand Central Rocket Co. 16 SRM first stage solid NOVA that I summarized in a different thread, and the all-liquid NOVA that I've also summarized...

The second pic is the converted "Midway class" aircraft carrier with a central gantry crane installed, which would be a floating crane/workshop for assembling the massive NOVA solid vehicles on the offshore launching pier, and would also provide living space for some of the workers...

Later! OL JR