Orion Ascent Abort Test... Little Joe 3?

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GlenP

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https://www.nasa.gov/feature/nasa-moves-up-critical-crew-safety-launch-abort-test
"In a test targeted for April 2019 known as Ascent Abort-2, NASA will verify the Orion spacecraft’s launch abort system. The test will last less than three minutes with the test crew module reaching an average speed of Mach 1.5, roughly 1020 miles per hour, at approximately 32,000 feet in altitude."
aa2_inflight.4k.jpg


With all the excitement over the Estes Little Joe, would it be cool to make a scale model of the 'Little Joe III'? I know NASA is calling it Orion AA-2, but to me it will be Little Joe III. If enough people call it that, the name might stick, who knows?
 
Hmm, so maybe MLAS should have been Little Joe III, and Orion AA-2 would be Little Joe IV?

Or Little Joe III, part Deuce (deux)... Little Joe re-imagined.... I also like Hoss, but that is kind of mixing metaphors. rather than a roll of double deuces on the dice for a Little Joe, Hoss was the big brother to Little Joe on Bonanza, but since Lorne Greene portrayed both Ben Cartwright and Commander Adama, maybe that’s okay.

Enough of the digression with the names, I need to get some parts to start scratch building one of these, for 18mm power. Need to decide on flame fins or clear fins. Any suggestions for where to get suitable sheet material for clear fins?
 
I found some clear plastic and lexan sheets in smaller sizes at my local Home Depot. Erockets has two types of pre-cut clear fins and the laser cut Zooch flame fins.
https://www.erockets.biz/semroc-las...och-flamefins-4-fins-3-32-basswood-sem-fdz-1/
https://www.erockets.biz/semroc-laser-cut-fins-clear-plexi-0-06-4-fins-sem-fcl-1/
https://www.erockets.biz/semroc-laser-cut-fins-clear-plexi-0-06-4-fins-sem-fcl-2/
And Hobbylink has clear plastic sheets of varying thicknesses, here's one:
https://www.hobbylinc.com/htm/pls/pls91253.htm
Dang, the Quest MLAS is a favorite, great flyer on 18mm composites. Now a historical blip on the radar.
Maybe Hoss would be the SLS, and Ben would be the Delta Heavy. Then the Ares IX would be Adam, since he disappeared one season without explanation. I remember asking my parents what happened to the brother in black. Oh well.
Adam Cartwright.PNG
 
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and don't forget Trapper John, M.D. many years after he returned from his Korean service at the 4077th M.A.S.H. unit, but he kind of looked different.

Thanks for the links. I tried looking at a crafts store and had no luck, should have tried Home Depot. I like the precut fins from SEMROC, those might be easy enough to use. I was on the fence about just adding fins in planform shape similar to the other Little Joes. Could also do a cone or ring fin, or a drag disc, but for 18mm I want to keep it low-drag and light weight. Just simple rectangular fins in grey primer that look like a stand might work.

The LES tower could be made from a dowel, but not sure I like the idea of a sharp stick on the top of a rocket. I have seen some cardstock models, that might be more suitable, but I can't find the templates that were used, just pictures, the old links seem to be broken, so I will have have to make my own. A dowel would be easiest... but maybe not the safest option, would be about the diameter of a typical pencil for the 2" main body tube I am planning to use.
 
If you want the tower to be frangible, you could make it out of cardstock. Or, a cardboard tube with balsa cone. I think a BT-3 tube is a little bigger than the diameter of a pencil. The LAS covering the crew module will be challenging, but having seen your cardstock models, I'm sure you'll come up with something. Myself, being creatively challenged, I would probably go with custom turned balsa or a 3D printed piece.

Here's how the DZ SLS spoofs the LAS:
IMG_20181201_110532.jpg
And this elliptical nose cone for the ST-20 tube might work:
https://www.erockets.biz/semroc-balsa-nose-cone-20-2-5-elliptical-sem-bc-2025/
 
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Hmm, so maybe MLAS should have been Little Joe III, and Orion AA-2 would be Little Joe IV?

Or Little Joe III, part Deuce (deux)... Little Joe re-imagined.... I also like Hoss, but that is kind of mixing metaphors. rather than a roll of double deuces on the dice for a Little Joe, Hoss was the big brother to Little Joe on Bonanza, but since Lorne Greene portrayed both Ben Cartwright and Commander Adama, maybe that’s okay.

Enough of the digression with the names, I need to get some parts to start scratch building one of these, for 18mm power. Need to decide on flame fins or clear fins. Any suggestions for where to get suitable sheet material for clear fins?

I believe it's Little Joe 3.2, Electric Boogaloo.
 
Screen Shot 2018-10-30 at 7.35.30 PM.png

Ha! That is the cone that I just got. It matches the contour fairly well. I built the Zooch SLS and EFT-1 a while back, the capsule & tower is much smaller size. I was thinking of using a similar construction method, but may end up rolling my own cardstock tubes around a dowel, rather then using a dowel itself for the tower. There are a few conformal internal nozzles above the main external Abort motor nozzles, the Jettison and Attitude Control motors, that I might just print as black on the cardstock template.

dsc_6099-jpg.245491
 
I believe it's Little Joe 3.2, Electric Boogaloo.
... in SPACE!

Part of the fun will be to figure out the roll pattern from the pictures above, will be helpful to use the Little Joe II drawings from Tom Beach & George Gassaway as a starting point, not sure where I downloaded that .gif from, here is a portion of it:
Screen Shot 2018-12-02 at 6.11.52 PM.png


Looking good. Will be following this build with great interest.

Started out as just an idea, but I guess this will turn into a build thread.
 
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Glen, just thought of something regarding the fins. This is the optional fin unit for the Fliskits Saturn 1B, for builders that don't want to add nose weight and use the scale fins only:
IMG_20181203_111225.jpg IMG_20181203_111259.jpg
Like a booster stage without the motor mount. Removeable for display, or use it as a display stand. For flight, friction fit the coupler and/or use white electrician's tape to wrap the two body tubes. Fin shape of your choice/preference. Simple and easy.
 
That is a good example, and very similar to what I was thinking. Not sure I want to use clear fins, but just have something that looks like a display stand painted in a neutral color, black or gray. The NASA video shows a launch pad tripod that I may just scale up to proper fin size, very similar to the fin can on your Sat 1B example.

Capture.PNG


I might even go with a boost skirt very similar to the MLAS, like a 3-fin version, as homage, lest that one be forgotten.
 
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The crazy thing about "Trapper John MD" was that Pernell Roberts looked nothing at all like a much older Wayne Rogers (Trapper in the original M*A*S*H teevee episodes) would have -- but he did look roughly like you'd imagine BJ Hunnicutt 25 years later.

And not only that, "Trapper John MD" was set in San Francisco, which was established in the teevee series was BJ's hometown.

It's like they launched the "Trapper John" show and then made the lead character into a 55 year old BJ.


Now, after that brief MASHjack, back to the topic of Little Joes -- i always wondered why NASA didn't build a "Little Joe v. 1.5" to test the Gemini ejection seat system-- see if the seats would eject under launch acceleration conditions.

I suspect they probably didn't want to know the answer.

Going a bit further, does anybody know if the Soviets ever had a "Little Josef" to test the Soyuz LES when they first added it to the design?

Vostok and Voskhod never had launch escape towers, just ejection seats -- not sure if Voskhod even had those.
 
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There were some rocket sled tests of the Gemini ejection seats.

weber_gemini.jpg


Also some ejection tests at about 40,000 feet from a fighter jet at Mach 1.5.

Didn't need to rocket launch a whole Gemini spacecraft to test that out. As it was, it was risky to use ejection seats, safest place to be at the time of a vehicle failure would be INSIDE of a very very sturdily build spacecraft (if it was pulled/pushed away as Mercury and Apollo had), not ejected out into the thin air! But Gemini was an interim rush job, to bridge between Mercury and Apollo. Indeed Apollo began LONG before Gemini did. But there was a realization that a lot of things needed to be learned and practiced that Mercury was incapable of (orbital plane changes for rendezvous and docking, Spacewalks, long duration of up to 2 weeks). So a scaled-up version of Mercury was relatively quickly designed, and outfitted with its own crude "Service module" to allow for long missions and orbital maneuvers (in Mercury, once the Atlas shut down, the capsule was stuck in whatever orbit it had, which slightly decayed. The astronaut had no control over the orbit at all, other than the one shot to press the retrofire button to re-enter. The attitude thrusters only pointed it, didn't move it).

Back to the Little Joe stuff, here's a link to to the Drawings part of the Little Joe-II stuff on my website:

https://georgesrockets.com/GRP/Scale/DATA/LJoeData.htm

Stuff like this:
Peanut_A-001.gif


Also lots of photos, and other info. Such as NASA Reports, that had nuggets like this:

A-004-3-7-(p39).gif


BTW - that roll pattern was not unique to LJ-II. I have seen other rocket testing using the same sort of pattern, such as Honest John, particularly at White Sands.

honest_john_02.jpg
 
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In addition to George's info, I've read accounts that the astronauts (the 16 in the first two crews) were *extremely* skeptical about the ejection-seat arrangement for Gemini-- first of all whether the seats could get them clear of an exploding Titan II in the first place, and then how much fun it would be ejecting into a Mach-plus airstream after about the first 30 seconds of flight.
 
...here's a link to to the Drawings part of the Little Joe-II stuff on my website:
https://georgesrockets.com/GRP/Scale/DATA/LJoeData.htm

Thanks! That must be from where I downloaded the image that I had collected earlier. Very helpful.


Snapped this earlier in the year at KSC. It is the only pic of the LAS I have. Any use to your project?...

Thanks, I could try to incorporate those logos into my decals. I wonder if that is the actual test article for the Orion AA-2 test flight.

For the fins, I am kind of leaning towards a non-scale mock up with an MLAS type of boost skirt extension of the main body, but maybe with just 3 black fins, numbered I, II, III, just so it will be a good flying model rocket. Still on the fence about trying to make clear fins, not much experience working with lexan sheet.
 
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Could have been a mock up or extra for the pad abort test, maybe? Logos seem to be intended for the article to be on display horizontally rather than in an upright flight configuration.
 
first cut at the roll pattern... test print on copy paper wrapped around body tube with balsa cone...

Screen Shot 2018-12-05 at 11.50.01 PM.png
DSC_8233.jpg
 
I think that one vertical bar should be a little wider, can't find any pictures of it yet. Will tweak it and hope I got it right.
 
Cool LJ2 video.

Updated roll pattern, I think this is basically consistent with the Little Joe II roll pattern, but with a top and bottom border, and a little shorter in height.

Screen Shot 2018-12-06 at 7.39.04 PM.png

still tweaking it a little, trying to make measurements from the photographs and CAD drawings, getting close enough, maybe.
 
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I think that one vertical bar should be a little wider, can't find any pictures of it yet. Will tweak it and hope I got it right.

They should all be equal width, unless it's unique for some reason. 1/12th of whatever the circumference is. t find it, wrap thin paper around the body, mark the overlap point, measure the width distance to that overlap point, divide by 12 for the horizontal spacing grid.

Refer to the Figure 3.1.5 original roll pattern drawing I posted, while the dimensions would be different the proportions should be the same. As in the overall height is shown at 120", and there are 10 equal distance (12" tall) "lattitude" locations for the black bars to begin or end. So that first single black bar at left, on your pattern, should be 1/10th height white under it and 1/10th white height above it, 8/10th tall black. So if the full height on the model roll pattern was 3", that bar would be 2.4" tall, .3" white above and .3" white below (and 1/12 circumference wide).

I am not counting the full-wraparound black horizontal stripes at top and bottom of this vehicle since those are not part of the standard roll pattern proportions. Is there a good photo showing the "three rectangle" area, to see if the white space is out of proportion from the 1/10 pattern? Otherwise those three should have equal white spacing, 1/10th tall white spaces in four places and each of the three black rectangles 2/10th's tall. In your drawing it looks like the black horizontal stripes at top and bottom are inside of the roll pattern area. I would expect those to be outside of the roll pattern area, but they might have done it different for whatever reason.

One incredibly stupid thing I cannot get over, about this one-time-only test. NO PARACHUTE deployment! As though the chute system has been given enough "real world rocket abort testing" enough times not to bother (this will be the only abort test other than a pad abort test many years ago). Hell nearly every chute test except one has been under very controlled test-drop conditions, and one of those tests failed spectacularly (chutes ripped off).
 
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My first iteration was to update the horizontal spacing, pretty much like you noted above with 12 equal alternating white/black portions around the circumference, I stretched the top/bottom bands for a little overlap in the decal wrap.

The vertical spacing was traced from the photographs that I could find on the NASA Orion web pages, but I was probably not that accurate or consistent when I was scaling them to my 2" dia body tube model size. I will tweak the vertical spacing using the 1/10th divisions, that should look better, and try to reconcile that with the height of full wrap bands, they may be additional 1/10th increments on top and bottom exterior to the pattern.

The CAD drawing in my post #10 came from a PDF on the NASA web and is probably the most accurate side view of the pattern, but it seems to be in different order than the actual hardware mock-up pictures posted on Twitter in post #2 above.
 
Hard to take measurements from the photos, since perspective distorts things. This side view CAD drawing is probably more consistent. Here is a comparison of the spacing with the three and two band blocks. They seem to be using 7 equal divisions for the 3 bar: 3 black + 4 white equal spaced bars. The top and bottom bands are a little thinner and not part of the equal divisions of the bars in the pattern. I think I have enough of an idea to make one final tweak to my pattern to match the CAD and photos that I have found so far. Screen grab from my working Inkscape drawing. Overlay with the Figure 3.1-5(c) roll pattern above for comparison.

Screen Shot 2018-12-09 at 9.30.00 AM.png
 
DSC_8242.jpg moving on to the tower...

DSC_8240.jpg

DSC_8241.jpg
 
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