Space Shuttle Launch Pad 39A with Challenger STS-6

[roma847]

Hello friends,

 

so far so good, but now there are on the GH₂ Press. Line even these four Fittings, which in my estimation should have a diameter about of 1 mm and a width of 0,5 mm.

 

Source: NASA

 

And who knows me a little bit, probably suspects that I will try these things at least once. At that at first I thought of my Lead wire Ø 0,4 mm, which I already used for similar things on the SSWS Pipes.

 

For this I wrapped the lead wire around the Copper wire (Ø 0,4 mm) and then separated this spiral with the Cutter chisel.

 

 

Then I rounded the rings around the copper wire with the tweezers to close the tiny gaps,

 

 

which then look like this.

 

 

The threading of these rings onto the bent line was then a tricky puzzle, but let still carry out. The insertion in contrast was rather difficult because the space for the tweezers for handling is very tight and the rings have partially bent up.  

 

 

 

 

 

But I was not thrilled by this result, however.
Then the thought of thin insulating tubing came to me, which I have already used successfully for such tiny rings.

 

 

To make as nearly as possible rings with the same width, I put the hose between steel rulers and then separated pieces of 0,5 mm.

 

 

These rings look a bit more like the real fittings, because their sides are straight, and they were also easier to thread up, 

 

 

and the result when installed looks in my view also much better than with the Lead wire rings.   Maybe the rings could be still a little bit narrower.  

 

 

 

The only question is again whether the effort is worthwhile, because one can barely see this Press. line on the upright Shuttle stack later anyway, how some other details also not, even though if the master builder would be more satisfied.

[roma847]

Hello everybody,

 

today I have made a few more experiments to make these Fitting rings, wherefore I've fished out again my Punch & Die Set (USM).

 

I first used Styrene (0,5 mm), from which I punched a small disk with Ø 1 mm,

 

 

which then was drilled out with Ø 0,4 mm, 

 

 

 

and then was threaded onto the Nickel silver wire (Ø 0,4 mm). 

 

 

The same procedure I did for comparison with Styrene 0,4 mm, whereto I used a normal Fileback fastener.

 

 

This somewhat narrower disc can be seen to the left of the 0,5 mm disc, and above that the rings made of Insulating hose.

 

 

Due to the uniform thickness, the punched rings would certainly look more even, whereas the rings made of Insulating hose are easier to manufacture and better fit the contours of the Cable Tray and the Feedline. As a result, I'll probably stay with the insulating hose variant.

[xffw45343tg]

Insulating sleeve gets my vote. Seems easier to ensure that it is concentric with the pipe too.

[roma847]

Thanks Kirk, 

then we agree, my friend. 

[Mustermark]

This level of detail is mind-blowing. If it wasn’t for the famous cent we would lose the idea of the tiny scale you are working at. 🤪

[roma847]

Thanks Mark for looking in on me again. 

These tiny details are no longer visible to the naked eye at this scale,  but they actually exist on the model.

And in the original photos or my macro shots, they always look huge, as well as the Cent coin,  which must always be there, that's funny. 

[roma847]

Hello everybody,

 

and today the new GH₂ Press. Line made of Nickel silver wire (Ø 0,4 mm), which is bent even more precisely, whereby it can easier cling to the Cable Tray and around the LH₂ Feedline.

 

Bending the wire was a bit more difficult, as the Nickel silver wire is less ductile than the Copper wire, but after a few tries it went smoothly.

 

 

 

And also with the Fittings from insulating hose the line fits well.

 

When inserting, I always put the long end first in the opening in the Umbilical plate,  

 

 

and then the front end into the in die TPS cladding of the Press. Line.

 

 

This allows me to paint the line separately and then finally insert it.

 

 

After that the LH₂Umbilical is done, I can go on with the LO₂Umbilical on the other side, where again the Cable Tray with the Supports has its turn.  

[roma847]

Hello everybody,

 

so then let's go to the LO₂ Umbilical, which can be seen from behind especially in the zoom in all its beauty.  

 

Source: NASA

 

Observing from the front, it is noticeable that at the LO₂ Feedline there is still this special Support, which is rather thin and sits directly below the LH₂ Cable Tray on the Crossbeam. Or maybe it's a part of the TPS Cladding of the Umbilical.    

 

Source: forum.nasaspaceflight.com (DDG40)

 

For the further separate construction of the ET/Orbiter Attachment, I have considered that it would be better to cut off the LO₂ Feedline at this point and to glue the back bow with the LO₂ Umbilical plate between the two Support Brackets and then to glue the thin support onto the front end of the bow. Then the other Support/TPS parts and the LO₂ Cable Tray as well as the end of GO₂ Press. Line will be installed.

 

The front part of the Feedline is too short anyway and has to be extended up to the Fairing on the Intertank. 

 

And only after the Flour coating process and painting of the ET all lines including the Ice Frost/PAL Ramps as well as the complete ET/Orbiter Attachment will be installed on the tank.

 

 

Before cutting through the Feedline I first had to find out the geometry and the dimensions of the Support-Plate, which was not that easy, because the parts are only temporarily attached.   

 

 

With the measured distance between Feedline and Cable Tray of approx. 2 mm I drew this little sketch, 

 

 

which I then transfered to Styrene (0,5 mm), 

 

 

then it was punched out with the Chisel-cutter,  

 

 

which then was sanded.

 

 

And this is how the test fitting looks on a Feedline dummy (Ø 3 mm).

 

 

 

That's it then again, next follows the separation of the Feedline and the test fitting of the bow.  

[roma847]

Hello friends,

 

the marking of the separation point on the LO₂ Feedline was more difficult than expected due to the limited space conditions, but then I still succeeded. And then I bravely took the saw, and the job was done.

 

These are the first images after the separation of the Feedline with the realization that the short bow was much harder to handle for testing, which is why I had to think of a new solution.  

 

And so I came back to my Transparency stencil, which was made for it and only had to be slightly shortened.   This allowed the bow with the stump above the Umbilical plate to be inserted into the large opening of the template and kept relatively stable.

 

 

And by clamping the template in my Mini vise, the bow was easy to see from all sides.  

 

 

I was pleasantly surprised at how well the front of the bow did fit under the Cable Tray,  

 

 

which was visible by placing the paper template. 

 

 

But after putting on the 0,5 mm Styrene support plate, the disillusionment came immediately,   because I had not thougt of it that the Cable Tray is also 0,5 mm thick, and the support plate with this then would be flush, but this is not correct because it must sit a little lower. 

 

 

Consequently, either a thinner support plate ago, or the plate had to be ground down to about 0,3 mm, which I then have preferred.

 

But more on that later.

[roma847]

Hello everybody,

 

no sooner said than done! So I've sanded the Support plate between two nail files to a thickness of about 0,3 mm, and I have to say that I liked it better than before.

 

 

 

Now, the bow had to be glued as exactly as possible between the Support Brackets, but unfortunately I had to remove the stencil, which had previously fixed the position of the bow.

 

 

 

The crunchpoint here, however, is that the bow must be aligned with the Feedline,

 

 

and the Umbilical Plate should lie flush against the opening of the Orbiter Door.

 

 

 

To accomplish this, I drilled the end of the Feedline in the middle and inserted a piece of Nickel silver wire as Centering aid. 

 

 

 

In this way I succeeded, first to glue the Support plate at the Crossbeam and then the Feedline-bow with the Support brackets, which will make the further work on the parts of the Cable Tray-TPS cladding much easier, since nothing can slip anymore.

 

 

Then I've bent an Evergreen Strip (0,4 mm x 0,5 mm) under hot air around a rod (Ø 3 mm) and glued one ring of it in front of the Support plate. 

 

 

Then I've scratched the so called Pivoting Support missing at Airfix and glued it just behind the Intertank.  

 

 

But this is only one half of the Feedline Support, as one can see in this image, as there is still a clamping ring over it, 

 

Source: System Definition Handbook SLWT, Vol. I (Lockheed Martin)

 

which should be much narrower than at Airfix existing ring, as the comparison with the original photo shows, so I would have to modify these rings also a bit.  

 

Source: forum.nasaspaceflight.com (Jester)

 

Then there are also missing the wider Rings in front of the supports, which I'll scratch too.

 

So all in all a lot of odds and ends, which is still waiting for me.  

[xffw45343tg]

This is just slightly more detailed than the ET I made with my daughter when she was about 4. We used a coke bottle covered in papier-mache and painted with a brush that was about 5cm wide. The (cereal packet) orbiter attached with adhesive backed Velcro as did the SRBs. There were no fuel lines.

 

I like yours much better Manfred.  

[roma847]

Thanks Kirk for your nice compliment. 

 

You know that I'm a crazy perfectionist and it's difficult for me to resist temptation regarding scratching tricky details.

[roma847]

Hello everybody,

 

and now to the LO₂ Cable Tray along with the TPS Segments at the transition to the LO₂ Umbilical Plate.

 

As always, before the Scratch-building of assemblies and parts there is nothing like a thorough inventory and accurate detailed analysis. ... ...

 

The beginning is again this photo for a better orientation, which helped me because of the direct side view already in the sizing of the Distribution box, on which I have marked the first three parts of this LO₂ Umbilical assembly. 

 

Directly behind the distribution box is with the Part 1 a trapezoidal support part whose dimensions (length L, and upper and lower width) I've determined by reference to the diameter of the LO₂ Feedline (Ø 3 mm).

 

Source: georgesrockets.com (George Gassaway)

 

On this rotated photo, one can see this here gray part a bit closer, whereby the linked original zoom is unfortunately rotated.

 

Source: forum.nasaspaceflight.com (DaveS)

 

Therefore, here is still a section in the original resolution, on which one can see that this part is directly connected with the Distribution box and with the LH₂ Cable Tray.   

 

And directly behind the oblique branch (Part 3) runs from the Cable Tray, which is connected with the Part 2 and passes over the Parts 4/5 to the Umbilical plate.  

 

 

Thus, only the width of the part  is missing, which I have determined from this photo, which allows me to scratch the Part 1.  

 

 

In this picture one can see the cables coming out of the vertical strut, of which one part, as just described, runs up to the LO₂ Umbilical plate and the remainder to the LH₂ Umbilical plate. 

 

In this rear view, the Parts 3-5 are admittedly covered by cuffs, but one can nicely see the entrance of the LH₂ Cable Tray into the Vertical Strut.

 

 

And in this order, I will now try to scratch these five parts step by step.  

[RichO]

  Wonderfully researched again, as always!  Good luck and have fun scratching these very small details!!

[roma847]

Thanks Rich for looking in on me again. 

 

Yeah, yeah, yeah!  The scratch orgy is going on till the end, therefore keep your fingers crossed please! 

 

BTW, it's time for you to show us something again! 

[James G]

Love the crazy details Manfred! 

[Pete in Lincs]

Lots of detail and all the better for it.

[roma847]

Thanks James and Pete for your nice compliments. 

 

Stay tuned, and you will see more of them! 

[roma847]

Hello everybody,

 

and now to the Part 1, which is small, but looks relatively simple, although in this image it is half hidden by the Distribution box.

 

Source: georgesrockets.com (George Gassaway)

 

After I had punched it with the Chisel cutter out of an ABS Plate (1 mm) and smoothed the edges, it was glued at this point, directly in the corner between the Distribution box and the Cable Tray,

 

 

 

as one can see in these two images. 

 

 

 

Then it went on with the Part 2, whose shape one can only partially see in the photos, which has made the determination of the dimensions more difficult. Therefore, here again for a better distinction the color-coded Parts (1-6) with their partially hidden contours.

 

Source: forum.nasaspaceflight.com (DaveS)

 

In the next photo, it looks like Part 2 is directly adjacent to the green end part of the Crossbeam (Ball interface fitting), what I first assumed, but which is not the case.   On the other side, it is directly adjacent to the LO₂ Feedline Bracket, what one can clearly see in the zoom.  

 

Source: NASA

 

And from this image I have determined some dimensions of the parts, whereby in my experience for the determination of Heights one should also use a Reference height, and for Widths accordingly a Reference width too.  

 

 

Since this is still not enough to be able to scratch the parts, I've analyzed this already several times shown photo (rotated) for the remaining dimensions, which is very well suited because of its high zoom resolution.

 

Source: forum.nasaspaceflight.com (DaveS)

 

However, this image is very confusing due to the many dimensions, which is why Part 2 can be seen here again separately. 

 

Strictly speaking, the bottom of the part is not flat, but has down this triangular extension, but which I have not marked here and will suppress, since with about 0,4 mm it should be almost "invisible" and can be safely neglected ...

 

 

With these dimensions, I've then tried to scratch the part, whereby I first wanted to place it in an Evergreen strip (1 mm x 2 mm), 

 

 

but which seemed a bit too puny to me. Therefore, I will start another trial with an ABS Plate (1 mm) too.

 

 

 

Previously I had drilled the opening for the GO₂ Press. Line (Ø 0,4 mm) into the Umbilical Plate and threaded the Nickel Silver Rod on a trial basis.  

 

 

That should be enough for today.  

[roma847]

Hello friends,

 

today first again the experiment with Part 2 on a ABS Plate (1 mm), in which the slope should come out better than with the narrow Evergreen profile (1 mm x 2 mm). This time I have also taken into account this triangular extension on the bottom, which could be eliminated if necessary. 

 

 

The punching with the Chisel cutter went relatively well, so that the contour had to be filed then only slightly, 

 

 

what was again the same tricky procedure as the first time, because the part was barely could kept between the fingernails, but only in the tweezers tip, and even then slipped again and again.  

 

 

In this image, one can see both parts in comparison, whereby the new part looks much more precise, whereby the lower extension is about 0,5 mm.  

 

 

And this is roughly the mounting position right next to the outer LO₂ Feedline Bracket,  

 

 

which of course I have tested by laying up the part, and what looks pretty good for now.  

 

 

 

Only at the point marked in red, I have to take away a little bit of the Crossbeam (Ball Interface Fitting), so that the narrow strip can advance a bit further, so that the tip of the part will be lined up precisely with the Feedline Bracket.

 

 

Next, with Part 3, the probably most complicated assembly group of the LO₂ Umbilical comes along, which presumably will be built from several components.

 

 

With that, in particular, the connection point of the channel running diagonally forward to the LH₂Cable Tray must be determined even more precisely, which unfortunately is in hiding and so far could only be hinted at.  

 

So all in all, a rather tricky matter in a confined space, which is why every handle wants to be well considered again.

[roma847]

Hello everybody,

 

let's continue with the adjustment of Part 2, for which here beside the Crossbeam (Ball Interface Fitting) the announced narrow recess was cut out with the Mini saw blade.

 

 

And as one can see, it's only a small cut, but leads to a clear improvement!

 

 

Speaking of Original arrangement, I'm not sure anymore when I take a closer look at my black and white reference photo of the tank ET-8, which as is well known was to be the firstly flown Lightweight Tank (LWT), that was used since STS-6. Only at STS-7 was used a Standard Weight Tank (SWT) once again, for whatever reason.  

 

Unfortunately, the resolution of the photo is not exhilarating even in the zoom, and the area of interest to me is in the dark and is unfortunately also obscured by the Vertical Strut.   

 

Source: forum.nasaspaceflight.com (Jester)

 

But if you bend your eyes and look more closely, you will recognize, I believe, that especially the obliquely upwards running part of the Cable tray behind the support (Part 2) seems to be much narrower than on the previously considered images, which however, from later missions, where starting from STS-91 the Super Lightweight Tank (SLWT) was used, which had been modified again.

 

 

To the following photo I will still inquire DaveS, from which mission it originates.

 

Source: forum.nasaspaceflight.com (DaveS)

 

And this photo shows the ET-122 at the last mission of the Endeavor (STS-134). 

 

Source: NASA

 

Let's see if I can get some more information from DaveS, because sometimes he still has cool photos in his hindquarters, which have already solved some riddles.  

[KevinK]

38 minutes ago, roma847 said:

Only at STS-7 was used a Standard Weight Tank (SWT) once again, for whatever reason.  

Manfred,

 

I was on the Shuttle program at Michoud at the time.

 

The reason for using a Standard Weight Tank - we called them Heavy Weight Tanks (HWT) at the time - for STS-7 was fairly simple and mundane: STS-7 didn't need the extra performance available from use of the LWT and an extra HWT was in existence and so was used to avoid wasting a flight tank.

 

Congratulations on your outstanding and painstaking work!

 

Kevin

[roma847]

Thanks Kevin for your nice help, which is very welcome.

 

Good to know that you were on the shuttle program at Michoud at the time. Maybe you can answer some of my special questions regading the STS-6 configuration.

 

Do you also have photos of the Shuttle Stack from this time? 

[KevinK]

Thank you, Manfred!

 

I'm afraid I don't have any Shuttle Stack photos, other than those available in books or online: on my work visits to KSC, cameras were a definite no-no for anyone other than officially-recognized photographers.

 

I was a Systems Engineer, mainly working propulsion initially - pressurization, liquid flow, etc, with some involvement in other disciplines. Later, I also worked Advanced Programs such as: ET derivatives and applications, such as Shuttle-C which eventually evolved into what is now SLS; the Gamma Ray Imaging Telescope which involved taking an ET to orbit and converting the hydrogen tank into a cloud chamber to detect and image gamma ray sources; the Propellant Scavenging Study, to deliver 250,000 lb of cryogens per year to LEO; and the start of Space Station Freedom, which evolved into the ISS, of course.

 

I didn't have a lot of involvement with flight-to-flight Shuttle activity so unfortunately I don't have much detailed knowledge of specifics of the STS-6 configuration. However, I am in awe of the information you have gathered so long after the time! One thing I can say, though: NASA "ordered" the tanks from Martin under a 60-tank enabling contract, but actually specified detailed contract batches only four tanks at a time, and often required variations within those four. Within engineering, we used to joke that no two tanks were the same, due not to any manufacturing errors, but to NASA's requested changes, often instrumentation for specific flight experiments.

 

Even within the early LWT series, major changes took place. For example, LWT-6 deleted the LO2 tank slosh baffles to save mass. We predicted underpressurization in the tank ullage early in the flight due to the liftoff "twang" effect of the 1.5 m lb of LO2 causing a geyser into the ullage space and indeed it happened but the presence of some helium in the space was enough to prevent tank collapse until the autogenous pressurization took over. Eventually, this kind of change was routine: observation of flight data on multiple flights would result in analysis showing where margin existed which could safely be reduced.

 

TPS configurations and production methods were a constant engineering change area. Some 40% of the cost of the ET was in the thermal protection: NCFI foam and the SLA. Much effort was made to reduce this by spray automation and other means, with some success. Always visible on the flight tanks were the hand-done final TPS closeouts and pull-test areas, as well as TPS trimming, especially on the ogive for aerodynamics.

 

Kevin

[roma847]

Thanks Kevin for your detailed insight into your many years of work experience,  which is very interesting and confirms the experience of other experts, such as Craig Capdepon, Vincent Morales and Scott "Shuttleman" Phillips, that each ET was unique and no two tanks were the same. So, in particular, the hand-done TPS closeouts were almost arts and crafts. 

 

In particular my friend Scott Phillips has given in his book "Remove Before Flight" a firsthand insight into a piece of American and personal history that was very valuable and helpful to me and my project. 

 

I would be very interested if we could still clarify one or the other question by PM.