Thanks!She looks great!!
Many other variables at play here, like balsa sheet thickness, but mass/weight typically tend to scale with to Volume rather than a linear length scale, so Volume scale ratio would be 1.5^3 = 3.375, your 150% scaled-up Orbiter weight comes in about 3.54 X the original, not too far off....Scaling up 150% in length doesn't equal 150% increase in weight...
I painted everything the same as I'd done on my Discovery model. I put on 1/4" launch lugs since I was probably launching this on a D engine, and maybe an E someday if it flies okay. I had to cut away a section of the corrugated intertank so the rod could slide freely, but touched up the paint so you probably can't tell without me showing you where the missing part is.
The nosecones for the SRBs were also ordered from Excelsior after I grabbed the wrong ones at JonRocket. The folks at JonRocket were nice enough to cancel my initial order on a Sunday after I bought the wrong cone for the ET. I notified them in time to stop the order. Unfortunately the order I did make for the SRB cones was wrong too but I didn't know it until they arrived. Excelsior turned a couple of custom cones for me and a few days later I'd had them painted and glued on too.
Thanks Gordon!
For the parachute, I looked online and found a chart for chute size vs weight. I had to estimate the weight at the time since I was not done and decided I needed an 18" chute. Digging through my spare parts I found an 18" nylon chute and I have no idea where it came from. So I used it.
After finding where the CG of the completed rocket needed to be and adding the correct nose weight to the ET nose, I weighed the entire stack, loaded with a D engine, at 351 grams. Wadding will add a little more I suppose.
View attachment 261308
Here's a picture of the final 150% upscaled Challenger stack standing next to the "stock" Discovery stack.
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I'm planning on flying this on a D12-3 as soon as I get a week of sunny weather so the big field near me is all dried out. I don't want it to land in a puddle of water. As of today we've had a week of rain.
The entire stack could curve over and hit the ground under power, leaving me with a pile of shuttle pieces. Or maybe the stack will fly high and the orbiter will come off, but it won't fly and will plummet to an early death. Anyone want to make a prediction?
Thanks!Mushtang...that looks INCREDIBLE!!!! beautiful job!
(Note, the thicker black areas on the wing, where the leading edge of the wings meet the cargo bay, were only on the Discovery. Future orbiters didn't have them. I didn't notice these until I'd already built my Challenger or I would have removed them from the wrap prior to printing. Oops.)
Fantastic work! Good luck on the test flight
I actually used the above fact to out geek some very knowledgeable space geeks while working at KSC. However you have the wrong orbiter. Columbia is the only one to have the Black TPS tiles on the Leading edge strakes. https://www.nasa.gov/centers/kennedy/shuttleoperations/orbiters/columbia_info.html
Hi, new guy here. I built two Estes 1284 kits over 20 years ago and was planning on building the entire fleet, but then I lost interest in model rocketry before even attempting to fly my shuttles. My Estes shuttles are long gone, but I am now getting back into model rocketry and just purchased a Dr. Zooch shuttle. I'll see how the first build goes, but I hope to eventually build the entire fleet. This thread is an excellent reference that should be a big help for my build.
I plan on using the wraps in post #495 to build my first orbiter, Atlantis. As a few people have mentioned, the thicker black areas on the wing, where the leading edge of the wings meet the cargo bay, were only on Columbia and were not present on the other orbiters. Has anyone corrected the wraps to account for this? I'm sure I can hack up the pdf files and try to correct them, but I figured I'd ask here first to see if anyone has already done this (and probably did a better job than I could do).
Also, I plan on using 65# card stock on all the wraps; I think the stock wraps are all 110#, except for the bottom wrap. Does anyone foresee any problems with this, or should I really go out and get some 110# card stock?
Are you planning on getting a new kit for each build, or making one ET and SRB stack and having all the Shuttles built separate on your own?
I'd like to get at least a couple of kits so that I have at least one spare ET and SRB stack. I'm not sure where I'd find the wood plug for the nose or the screw for the back, though, if I built my own orbiters. I do have my eyes on a few other Dr Zooch kits (SLS and Saturn V are at the top of the list) so it would be great if I could save some money on the shuttles to put towards the other kits.
Finally launched the 1.5x version today on a D11. The stack flew up fantastic, just like the original version, but the orbiter failed to glide. It fell nearly straight down, nose first, and the rudder broke off on impact. The rudder is easily fixable, that's not a problem.
My guess is there's too much nose weight in the glider? The CG was in the same relative position as the smaller version, and the elevator was positioned in the same angle. For this bigger version there isn't a lot more travel left to bring the elevator up, but there is some.
Anyone have any suggestions? My plan is to try and cut the nose off and build a new one, and put far less clay in it so that the CG is much further back. If it doesn't come off clean I can build a completely new orbiter I guess. But the only thing I can think of is that the CG needs to move back but I have no idea how far.
I haven't tested this orbiter by hand tossing it since the last couple of times I tested the normal sizes orbiters the tests weren't helpful. On those, sometimes it would glide and sometimes it would tumble, but they glided every time from being launched.Mushtang, how does the orbiter glide when hand tossed?
When I removed the nose weight I didn't make any adjustments to the elevator since it was in the same relative position that the other orbiters flew successfully. I wanted to change only one thing at a time and see if I could get a better idea of what was wrong. Not sure if the position of the elevator would cause a tumble vs glide.Did you adjust the elevator when you lessened the nose weight?
From what I can tell it was more of an all three axis tumble. I have a video that I haven't taken off the camera to watch on my laptop yet. Was of town all last week on business and was too bummed to look at it the day of the flight.how does it tumble, nose over tail, in roll, more of a spin or all 3 axes?
When the orbiter came off the stack was pointed down (if I remember correctly).If you can't get enough speed hand tossing it you might be able to rubber band catapult it for test flights. What was the orientation of the stack at separation, I could see if it still pointing up where it might have a difficult time recovering. I'm not a glider expert by any means but those are the things I'd ask myself.
Moving the CG aft will definitely affect trim position on the elevator for a stable glide.
That's the plan. As soon as I get a calm sunny afternoon without other plans I'll spend some time throwing it in the back yard and off the deck, making adjustments to see what difference it makes.Interesting, if I remember my orbiter worked fairly well in hand tosses, I need to re-trim and repair it though, mover damage. Give the up-scale a toss and see if it works the larger size may make it more easily toss-able. Can't hurt to try I'd wait for a really calm day. With a three axis tumble that could be tricky to tease out,
From what I can find on the internet about gliders I'm thinking that it just might be too light. Apparently when they say that weight is the enemy of a glider that only goes so far. Unfortunately the only information I can find on gliders is for the little balsa gliders, or similarly shaped planes. Nothing about delta wing gliders like the shuttle. I suppose if I crack the code I can create a page and share what I've found with the world.I doubt the orbiter as a whole is too light but that seems to be tumble recovery, check your left-right and vertical CG's verses your original orbiter as well perhaps.
If there was a stable glide before moving the CG then that's true. In this case the glider nose dived before moving the CG back and the removal of nose weight was an attempt to correct it so that it could fly. The result was a tumbling glider, not a stable glide.
That I agree with. But the first time you said it you added "for a stable glide".No, moving the CG will always affect the trim position.
That's the plan. As soon as I get a calm sunny afternoon without other plans I'll spend some time throwing it in the back yard and off the deck, making adjustments to see what difference it makes.
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