Ye Olde Rocket Forum - View Single Post - BT-80 based Saturn V/ "Saturn I-F"

Ok, finally got some more work done on the Saturn V/Saturn I-F. Got to checking in the ROTW and found that the Saturn V had 108 corrugations on the S-IC intertank, and 216 on the S-IC forward skirt. IOW, the corrugations should be about half the size on the fwd skirt as on the intertank. Peter Alway lists the S-IC thrust structure as having the corrugated stringers 2 degrees 48 minutes apart . Figuring that a circle is 360 degrees and every degree should be 60 seconds of arc, that's 21,600 minutes of arc in a full circle, divided by 2 degrees 48 seconds per stringer (168 seconds of arc) gives 128 stringers (rounded off-- close enough for gov't work). Close enough to the 108 on the intertank to use the same corrugation pattern. SO, I used the "wide corrugation" paper I've had for awhile and custom fitted the panels between the engine fairings on the base of the S-IC and then cut the intertank band that links the top of the kerosene tank and the bottom of the LOX tank. For the forward skirt at the front of the stage, I switched to the foil-coated paper I bought a couple days ago. Carefully marked and cut out with a hobby knife, back coated with white glue, and rolled onto the tank. Here's the results.

Next I switched to the Saturn I-F. Since the first stage/booster pod is built almost identically to the Saturn V S-IC first stage, only smaller, I used the same corrugated white paper for the thrust structure and intertank, and switched to the finer corrugated foil paper for the first stage forward skirt, interstage, and S-IVB upper stage aft skirt, and the S-IVB fwd skirt. SO all the wraps are done on the Saturn I-F.

Next I have to continue debating what to do about fins on the Saturn I-F.... The "booster pod" would have been the basis for the first stage on the Saturn I-F, and that booster pod is not shown with fins. The booster pod is very similar to the Saturn C-3 proposal from 1961, which was never built, and it was never shown with fins (of course the early Saturn I's had no fins either.) SO, considering this is supposed to be an 'evolved' Saturn IB, it's likely that the fins would have been dropped. If we presume they were, then I'll need some kind of add-on fins for flight (and I already have a design in mind for removable clear flight fins). The other alternative is that they'd have grafted on some Saturn I or IB fins or Saturn V fins-- though the fact it only has two engine fairings complicates that issue somewhat. Guess I'll play with it in Rocksim and see what I can come up with. Given the fact that some work had been done to get rid of the fins on Saturn V, which wasn't implemented due to it's low production (but would likely have been implemented had Saturn V production resumed with a second run-- there were literally THOUSANDS of weight and labor saving changes ready to be applied to a second run of Saturn boosters had production ever resumed!) So, that being the case, it might be simplest to go with clear fins and call it good...

More work to do! Later! OL JR