SpaceX Interplanetary Transport System (updates)

[DocM]

 

[SALSN]

Wow, that really puts the size into perspective. Can't wait to see that monster take off!

[DocM]

Hello....sea pressure tests off Anacortes, WA

 

Reddit thread....

 

Quote

 

Thought you might enjoy some pictures I took. Yes, my camera is a potato.

 

A few years ago one of the large manufacturing buildings in our small town got bought by a bunch of strange suits, supposedly by Boeing for special projects. Extremely tight security.

 

Even the shipping containers outside had biometric locks on them.

But yesterday they brought this thing out and loaded it onto a barge, supposedly for "destructive testing".

 

Less than 24 hours later, it has already returned seemingly intact.

They could not have gone very far at all, so everybody around here is pretty curious about what they actually did.

 

I saw a few man-sized silver tanks that were being moved off the barge as well, which were also venting.

 

 

UNLOADING

 

Photos below....

 

 

 

 

 

[BetaguyGZT]

We know what this is.  

[Draggendrop Veteran]

Just checked reddit, no info on the pressure, gas used or duration yet. Guessing a short low pressure test and it passed.

 

Looks good and that thing is huge.

 

[BetaguyGZT]

They could have done a low-pressure test inside the factory ... with air. Nah, they put it through a top-off at full pressure out to sea, where nobody would get blasted to high heaven if it failed. That's the only reason they'd go through this much trouble.  

[Draggendrop Veteran]

I believe the normal pressure is low since the turbopumps are the ones that build up high pressure. Low pressure can still do a lot of damage. If low pressure is the operation, they probably used a percentage of burst, which would be several multiples of normal operating pressure.

 

Hopefully we will know from the grapevine soon.

 

[DocM]

They said about 67% of burst pressure for the test, and bursting that bad boy would take some serious effort.

[DocM]

Built at the former Pacific Marine Center, Anacortes Washington. 36,000 sq/ft refit building.

 

[anthdci]

the size of that thing!

[DocM]

14 minutes ago, anthdci said:

the size of that thing!

Largest Class 5 carbon cryo-tank I've ever seen. Lordy!! 

[FloatingFatMan]

1 hour ago, DocM said:

Largest Class 5 carbon cryo-tank I've ever seen. Lordy!! 

And that's not even a full scale one, is it?

[DocM]

12 meters. For the spacecraft it's the largest tank. The boosters tanks will be the same but much longer.

 

[BetaguyGZT]

It's a safe bet they'll test each of them individually like this.

[DocM]

Yup. Don't want a failed tank test to take out your building, the neighborhood, the marina and the state park across the bay.

[FloatingFatMan]

44 minutes ago, DocM said:

Yup. Don't want a failed tank test to take out your building, the neighborhood, the marina and the state park across the bay.

... Or the space craft when it's half way to Mars, or on the surface and it takes out the colony...

[Jim K Global Moderator]

18 hours ago, DocM said:

Hello....sea pressure tests off Anacortes, WA

 

Reddit thread....

 

 

Paint that Red and White ... what do you got?

 

A very large fishing bobber.  

badum tish

 

Very cool though.

[Draggendrop Veteran]

4 hours ago, jjkusaf said:

Paint that Red and White ... what do you got?

 

A very large fishing bobber.  

badum tish

 

Very cool though.

j/k    Leave the test article dark and list it as the world's largest bathroom tank float.

 

 

Side note, Doc will know more, but I believe the Falcon 9 tanks were at 50 psi, which is approx 4.5 atm absolute. Low pressure, high volume feed to main engine pumps, which would be high pressure, reduced volume output, when compared to fuel tank exit volume.

 

With the tank test, my guess is a cheap gas used, preferably with a smaller atomic structure than the fuel to be used, for the leak test portion....pressurized and monitored with test liquid applied to leakage area's if required, We do not want a vapour leak on a fuel tank.

 

Devastating bombs are at atmospheric pressure, but are encapsulated for the initial gas expansion. Although this is a low pressure tank, the surface area is huge and the destructive power of this tank, with fuel, would be numbing....

[DocM]

Falcon tanks are 20-50 lbs pressurized, but they're transported as the trailer backbone (front & rear dollies) with a very low pressure fill of nitrogen.

[DocM]

This Composites World article is from 2013, but it's a good one about Janicki Industries - SpaceX's 'Composites Guys.' They sound like the carbon composites version of SpaceX. 

 

300 layers of carbon? 

 

http://www.compositesworld.com/articles/janicki-industries-breaking-the-mold

[Draggendrop Veteran]

6 minutes ago, DocM said:

This Composites World article is from 2013, but it's a good one about Janicki Industries - SpaceX's 'Composites Guys.' They sound like the carbon composites version of SpaceX. 

 

300 layers of carbon? 

 

http://www.compositesworld.com/articles/janicki-industries-breaking-the-mold

From the article...

 

Quote

 “If we haven’t thrown anything away in awhile,” quips one manager, “Peter [CEO] will challenge that we’re not pushing boundaries enough.”

That's all I need to hear...I like these guys.....

[BetaguyGZT]

I like him.  

 

I had occasion recently to have in my hands personally a few 1.5 x 1.5 inch pieces of specially-processed, compressed carbon fibre like what's being described, but with "only" (TM) 150 layers ... that stuff withstood a 100-ton press without budging. Very, very light, very solid. and very cool. Made a really neat noise when you tapped it on stuff. Sounded like wood but had a higher pitch. The higher-ups were astounded.

 

Stuff was light, really light, for what it could do. Impacts? No problem. Load bearing? Pfft, whatever -- it'll sustain whatever loads ya want it to. Temperatures? HAH. It LAUGHS at high and low temperatures and goes about its' business. Anything under 4000F it just tells it that it's cute. Seriously, it's the new super-material.

 

It'll replace metals, mark my word -- at 1/100th the weight.  And it's not susceptible to shearing or torque snapping, either, like metal is. It'll flex and bend, or needed, then go right back to whatever shape it's supposed to be at. Great stuff.

[BetaguyGZT]

*or = if. Ack.

[BetaguyGZT]

Just talked to my brother about this material and it's uses. Lots of Aerospace companies are getting clued in, and apparently there's a "big interest" (his words) in exploratory testing for structural uses -- including the heaviest parts of hulls -- with carbon composites like this. The weight savings throw off the balances quite a lot with Air and Spacecraft in simulations, so everything has to be reworked and re-thought. They essentially have to "learn how to fly again" using these materials, because engines are way too powerful. It's like strapping a Merlin onto a Station Wagon, he said. "Overkill". Your thrust-to-weight ratios become 4.5:1, even 8.0:1, using these materials. Gotta scale things back.

 

Most of the weight in a jet, before you add fuel, is pure bulk from the superstructure that holds the thing together. Body panels, and such, those are actually fairly light. Sheet metals perhaps 1/8 of an inch thick at most. The heavy stuff is the framing and ribbing that adds up quickly. Designers have had to boost engine power over the years to compensate, and used this power/weight ratio to "balance" these craft as a way to make them stable. These carbon composites, super strong and super light, throw off that stability so now they have to redesign software and even hardware (these engines especially) so that they can rebalance them.

 

What it means is that we'll see vastly improved fuel efficiency out of existing engines. Let's say SpaceX redesigns a Falcon 9 with a Carbon superstructure and builds new Fuel Tanks that are like the ones that'll be used on ITS. The Merlins will have been rebalanced and the Flight Software recrafted to deal with all the changes .. everything necessary to make the Falcon fly properly with all the new changes.

 

She's still gonna be heavy. After all, most of the weight of a Falcon-9 sitting on the Launch Pad is fuel. The reason we'd have to take into account all of the changes would be the last 15 seconds of flight on the S1, when she's starting to run lean. Those Merlins can and will start to overpower that thrust-to-weight balance I just talked about. The "Merlin on a Station Wagon" effect. Instead of a 4.5:1 TWR in those last 15 seconds, we'd rapidly approach something on the order of 12:1 or more. That's undesirable, because the rocket would start somersaulting even with a payload. So what we need the Flight Software to do is throttle back and maintain a proper application of thrust-to-weight, like the Atlas-V does in its' flight profile those last 30 seconds or so. We've all heard the Flight Commentator, that "4G Thrust Mode before First Stage Separation"? Same thing. It's because they're preventing that RD-180 from doing the "Merlin on a Station Wagon" thing and causing a somersault, so they throttle back the RD-180 on a (likely automated) curve relative to vehicle weight.

 

So, yeah. That's the skinny. These materials are making a big impact, and we're gonna be hearing a lot more about them over the next few years.  

[DocM]

Which is why we have that huge ass tank that's as light as an empty Dragon, and yet is the backbone structure of the largest real world non-station spacecraft ever built.