CEV, going backwards one step at a time...

[spacefire]

ok...will the J2-S need to be man-rated? <br />if so, why not man-rate and use an RS-68 instead, which is has even better payload performance than the SSME. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[nacnud]

The J-2S was destined for the Saturn V, do you think it was manrated? <img src="/images/icons/smile.gif" />

 

[rocketman5000]

The increase in the tank size from using a lower isp fuel . I realize it is a good thing to quote, however lunch break was ending and I had to be breif

 

[frodo1008]

I doubt that these engines have been affected by such storage. In the 1980's we were still refurbishing old atlas engines systems that were built for the Atlas ICBM itself back in the 1960's. They were being refurbished for use in either NASA launches or commercial satellite launches. I also doubt that these engines were stored in such excellent facilities as the J2s engines were stored in. They had come directly out of the missile silos, and had spiders and other things in them!<br /><br />I was one of the inspectors that was used to inspect the cleaned up parts, it was truly amazing how well built these engines were! I inspected the dimensions of some of the turbopump housings. In one such measurement, I put the housing on its small diameter and ran an indicator around the large diameter bolt area. I remember being absolutely amazed as the one face was to be within 0.002 parallel to the other, and the 0.0001 indicator I was using didn't even move at all!! It should be remembered that humdreds of these engines systems were being built even while we were building the engines for the mighty saturn!<br /><br />Rocektdyne's employment in the mid 1960's was some 25,000!! And the workmanship was simply superb! I am certain that it was this same workmanship that was used on this J2S program!! <br /><br />So even after some 40 years of storage I think that these engines would still be in great shape, and would be more than needed for the second stage of the CEV stick vehicle!! And yes, these were built for the Saturn V, and so would already be man-reated also!

 

[josh_simonson]

>I imagine the J-2S is further along than I thought. After all they made Aerospike engines with a couple of them. So I imagine the tooling is still around for them. <br /><br /><br />They built the aerospike engines with parts of old J-2S engines that came out of storage. Rocketdyne stated that they no longer had all the tooling, but that with modern CAD/CAM technology they can re-create it relatively cheaply (compared to the original tooling). If they were ready to go, they wouldn't be saying they need 4-5 years to resume production.<br /><br />I'd expect some of the old J-2S engines to be used for testing and test flights, but new ones will be required for human flights.

 

[john_316]

What do they do with the tooling once a production run ends?<br /><br />Are they like molds and they go break them like a molder or minter?<br /><br />I was wondering because you woudl think some of the things such as the piping and things could be done at the moment and the harder things perhaps the pumps would have to be retooled in a new machine or they would have to locate some of the older machinery if they didnt destroy it?<br /><br />Any answers to this? Because sometimes I am a packrat and wow once in awhile I'll come across a 486CPU I threw in a storage box many years ago. Wierd ya know!!!<br /><br /><img src="/images/icons/smile.gif" /><br />

 

[spacefire]

so maybe we DON'T want 60s era engines? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[nacnud]

Would the process for these engines be something like this?<br /><br />Get engine out of storage, make a CAD drawing from the engine, build a new engine useing modern tooling, test.<br /><br />Notice the lack of development needed.