Satellite Smithing

[Popeye the Sailor]

I only really touched on it before, and I never did finish my prior thread, but I wanted to write it a bit more concisely.

So for the better part of a decade I worked in the aerospace industry helping design, and then directing the build, of commercial spacecraft. Sirius radio, XM, Directv and quite a few others were all things I had my hands in.

I'll do my best to relate what goes into actually doing this, and answering any questions one may have. I cannot answer everything or get too detailed lest I get famous. That said, let's begin.

So at some point (if you're lucky) you get a program assigned specifically to you. This is typically a good day as it takes roughly two-three years to build one. In my time doing this, I was the primary on three satellites. It's good because now you have job security for a while longer. Go celebrate and pick up a shiny new bike.

Next you'll talk to your configuration engineer and get a set of drawings that you may or may not want to give feedback on-such as....where is this supposed to go? I can't support this item here-there's nowhere for a bracket. Etc. It's a week of tedious nonsense. Basically your drawings look something like this:



In fact that might be all you get, along with a parts list of a few hundred thousand parts. My job entailed 1) acquiring those parts 2) tracking them and their installations 3) creating work instructions so that things would go together in the right order. Various components would be tested as they were installed, which means removing them was a huge waste of time. It's a one-off thing-put it together once, in the correct order.

That in of itself is complicated enough-go one and buy a box of parts that should make a motorcycle and put it together right the first time. If you had to remove nothing along the way, I'd be surprised.

What really complicated it was that not all the parts would be available at once, but they wanted you to get going for the sake of image. Please install the countershaft sprocket because we have it-the countershaft will be here in a month. Yeah.

Oh and it has to work the first time.

I drank a lot.

[Popeye the Sailor]

So, sticking with the previous photo, see the two panels where the arrows "Louvers" and "Onboard Computers" are?



Those are the comm panels, and that's what one starts with. Giant composite panels-think 8-14' long, about 6' wide, and about 150 lbs.

Strong, light, don't drop anything on it. If you do drop something on it let me know-we can't fix it post launch. Probably as strong as a coke can-also one of the primary structures. Those panels have tubes running through them to distribute heat. Full of pure liquid Ammonia. It's heavier than air, so, if you break one somehow, climb. It won't support life.

So you get yer happy little panels and life isn't too complex at this point. It's like having a motorcycle frame and you're just bolting shocks to it and running a wiring harness. We're running the wires, we're installing the doohickeys, were still seeing our spouses at this point.

Now doohickey installation was very straightforward. I would acquire the doohickey and fill out a ream of paperwork stating I had the make the beast with two backsing thing.
I would give it to the tech who would then open it with a Quality witness, and they would document it's condition.
Next they'd make some special heat-transferring type glue (this is a multi hour process) and stick it in the correct location, as well as securing it with fasteners. The tech would prove they had the right fasteners, tool, torque certification (for both tech and tool), prove they could use it correctly on a meter that measure torque, and then put the fasteners in and torque them. Then you'd put a witness mark on them to prove they had been torqued, and then a few more reams of paperwork.

It would often take an entire shift to do one thing.

I needed to provide work instructions for each of those steps or they would not do any work.

I also had to verify that all the paperwork was done, and that the thing was actually where it should be, how it should be.

[Popeye the Sailor]

Ye olde office.

[Popeye the Sailor]

So anyway, we build up the comm panels

I found a better picture btw:



And once built up you mount 'em to the central cylinder. For those of us who drink like I used to, that would be the round thing in the middle.

How we did it was the panel was mounted to a big old aluminum frame, and we'd attach the crane to one end, and put some wheels on the other, stand it up, mount a counterweight to the back, and ease it in to the central cylinder.

Like so:



That line of vertical circles in the leading edge of the comm panel is where the bolts would go. Very important to bring it in nice and square, and to watch for potential interferences.

The hardest part of this was not so much that everyone would come to watch, but that there was a film crew with their billion watt/8000 degree lamp that was typically shining in my face. I grew to hate this. Claiming I was an aborigine and that the camera would steal my soul did nothing to dissuade them. Eventually when they'd ask what the schedule looked like for video purposes, I'd tell them the wrong day so I wouldn't see them. They quickly learned to not ask me.

[Popeye the Sailor]

Here's a video of misc nonsense. At 29 seconds in you can see a comm panel being made vertical for mating purposes. There's a joke in there somewhere. At 34 seconds it's being brought in to the central cylinder. 42 seconds in shows what a satellite would look like at main body with both comm panels mounted.

https://www.youtube.com/watch?v=K5676nQ9VlM

So, at this point we've hung both comm panels that we previously built up and now we spend a lot of time connecting them to each other so they can all talk happy happy like.

The other main task is running thermocouples throughout the entire thing-on all units, various parts of the panel, and covering everything else in thermal blankets. Why? It's going to go in the thermalvac chamber next.

The thermalvac chamber looks like a giant blue pumpkin. It is massive. We put the satellite in there in a (mostly) flight configuration, and suck all the air out. Then we get it realllly hot, then reallllly cold, then we repeat that shit for about two months to make sure nothing internally gets too hot or too cold. There are both heaters and things that cool built into it, with the end goal being that everything stays within certain temps. I don't know what those temps were, so go on and assume they were temps that would facilitate allowing the satellite to continue to work.

Here's a picture of it:

[Popeye the Sailor]

Now, it was imperative that nothing gets left in there. Say you drop your pen-well...it's going to melt and outgas whatever it's made of. Said gases will settle on every thermal surface.

Don't drop shit in there.

I never did like working inside there-the floor was a weird grating that wasn't really supported all that, uh, great, and it would shift slightly under my bulk. I'd end up with this weird combination of claustrophobia coupled with a fear of falling, and those don't typically go together. As I was also in charge of the mechanical team and the mechanical configuration of the satellite, I'd basically be the last person in there, which had it's own set of concerns.

We did manage to put a satellite through the whole test with a bat in there. No, not the baseball kind. Poor thing. I had great difficulty writing that up as a problem.

Problem is: Desiccated deceased bat found in thermalvac chamber with satellite.
Should be: No desiccated deceased bat in thermalvac chamber with satellite.

Luckily, I was not the party who had to come up with a solution to prevent it from ever happening again. Bat alarm? Bat be gone? Who the make the beast with two backs knows.

[Popeye the Sailor]

A few more pictures of the thermalvac chamber, just for scale of the thing:



and the room is was in:



Some dude fell in it one day. I don't know how he managed that. He did survive, but he was hurting, and it was not easy to get him out.

[Popeye the Sailor]

So, we've managed to cook the thing for about two months. Pull it out, serve with whipped cre.....wait no, sorry.

So we pull it out and we mount the tower on it. The tower would be the doohickey above the grid pattern bit. Yes-that giant piece bolts on-it weighs less than 200 lbs, and it's ~6' tall or so. The grid pattern bit would be the solar arrays-more on that later.



The reason it was done in that order was because with the tower on, it wouldn't fit in the thermalvac chamber. Satellites have grown over time.

So tower is on, make the thing as close to flight configuration as possible, and now we test a bunch of different aspects of it.

First up, the acoustic test. This may have been my favorite. We would transport it to an acoustic chamber (we didn't have one). The acoustic chamber is used to subject satellites to the same noise that a launcher produces during takeoff and as it flies through the atmosphere. I was told it would be loud enough to kill you if you were in there, so instead of going to 11, it went all the way to Mother-in-law. I decided not to test the livability of the chamber.

As most of out acoustic tests happened at the nearby Lockheed-Martin facility, no pictures exist. They were frowned upon there. In fact, security was tight enough that going to the bathroom unescorted was not allowed. Nothing makes you feel like a kid again like asking if you can please go pee.

I did dig up a picture of a different satellite in a different acoustic chamber to give you the idea.



The noise would be coming out of the round things in the wall.

[Popeye the Sailor]

There is no real order to these tests-just based on facility availability. Keep in mind we were trying to do 10 of these per year. There were bottlenecks, fights for resources, and outright theft of hardware from one program for another. This left the person who got robbed having to explain for the shit they signed for.

I typically had minimal issues because I was a very nice guy. I'd happily cover for anyone who needed time off for anything, and then I would rob them blind and feign ignorance. "Hey we're ready for the next test and they can't even find all their bolts! We should go first!"

Before I started that gig I wasn't a liar or a thief.

Anyway one of the other tests we'd do is the CG/MOI, or center of gravity/moment of inertia. Gotta know where the weight is-I mean-we're going to fly it, so, if we're going to put our thrusters to best use, helps to know where the weight is. We'd do it both horizontally and vertically-basically balance the whole mess one some giant machine and spin it.

That entire L-shaped frame would spin, spacecraft and all:

[Popeye the Sailor]

So we know how to balance it, and it'll survive the noise of a launch-how about the vibrations?

Oh yeah-faster baby. Harder. Only the first minute is worth it.

https://www.youtube.com/watch?v=GEwc6Poi4dg

Need shake it in all directions too-not just up and down.

[Popeye the Sailor]

We also need to test the things that deploy post launch.

I mean-look at the square box and you'll notice it looks nothing like a launched one:



We can't launch something that big, so the stuff that sticks out needs to be folded up and needs to unfold when we tell it to. The issue being it's all designed for low gravity situations, thus the motors/etc that would control these things can't hold them up on earth.

We had to get creative with fixtures, giant balloons, etc to offload the weight and see if they would launch how they should with no interferences.

Here's a video of a solar array deploying:

https://www.youtube.com/watch?v=S5VLlBcV7JU

[Popeye the Sailor]

I really never liked moving the satellites. The way they had it set up always involved this giant metal fitting about an inch away from something delicate enough that a Q-tip would pierce it. That and basically the only way to access what one needed to access was to be under a suspended load, which is just an accident waiting to happen.

One day we were on a lightweight dolly made to just roll a s/c around on-not the type what would go vertical/horizontal/rotate. That saved me-I had an offsite crane operator because we were doing a test at the Canadian Space Agency, and they had to run the crane. We had hooked it up to the little dolly, and were removing the sling, and I told the crane operator to go down, and he went up.

Twice.

Luckily the dolly was light enough that it just came off the ground. If we were on the normal dolly he would've torn the satellite in half. I was famous for a while.

The only reason I wasn't shitcanned over that was there they needed to move it again the next day, and there was no one else available. Getting entry to that facility was a two week+ process. They couldn't wait, and they couldn't very well let me keep doing the same job after the screwup and then fire me.

In the end they blamed the crane operator and let me keep on keepin' on.

[Popeye the Sailor]

Here's one of the more epic impossible things I recall:

https://www.youtube.com/watch?v=MdjWa0giVfI

Yes, it's worth five minutes of your time.

[Popeye the Sailor]

So, we've done the solar arrays and one *very* fancy reflector.

Most of them looked like this when deployed:



When frightened, the satellite expands to intimidate it's enemy....

Here's a video that is likely sped up-the process was slow as hell.

https://www.youtube.com/watch?v=TSIaTNMeL6k

That's basically the last thing we test to make sure everything is happy mechanically.

From there, we go into yet another test.

[Popeye the Sailor]

Next up, now that we've verified the thing works, can withstand the rigors of space and a launch, we need to figure out where the signal it'll bounce off it's reflectors actually goes. This is simulated in the compact antenna test range, aka CATR (cater)




I never felt...good after working in that room. They never told us what those weird foam absorbers were made out of, but it was mentioned to get out if there was ever a fire, as they would emit cyanide gas.

The satellite would be put up on that stand, which rotates and tilts for testing purposes, and then the reflectors tossed up there too. That was never easy-see the surface facing us? Don't touch it.

Please note, for each and every one of these tests, the satellite was moved from it's handling dolly to the test location. Sometimes this involved it going into a container, onto it's handling dolly, then to the test location, then reversed. Each move would take about a week to set up, get the paperwork for, and four hours to do if you were lucky, but more likely 6-8.

As I was test conductor, I was responsible for all that, along with spacecraft and personnel safety. You can't leave unless someone with the same certifications covers for you. As we were often offsite with no backup, I spent a lot of satellite moves in desperate need to pee.

There would be roughly 30-40 moves during a spacecraft build, and they were all difficult.

These aren't small things-they don't move easy. Picture for scale:



While we're at it-see how it's horizontal (or getting there)? The part that gets connected to the handling dolly?

Glued on.

Terrifying.