The Cryo Composite Tank has landed...

Proof that whales can fly? The super-guppy landed at Redstone airfield today, carrying the cryo composite tank test article. Looking forward to breaking it! :)

Cryo Composite Tank Development Testing

NASA’s Game ChangingDevelopment Program is aiming to advance composite materials technology for the purpose of manufacturing light weigh liquid hydrogen (LH2) fuel tanks for the next generation of rockets, possibly starting as an upgrade to the SLS upper stage. Current technology involves baking composites in an autoclave, which is not very feasible for a 5.5 meter (~18’) diameter tank. A second hurdle is the fact that hydrogen has a way of permeating and escaping from most containers. If successful, this program will pave the way for industry to produce high performance composite materials at less cost, without the need for large autoclave ovens.

NASA’s Marshall Space Flight Center (MSFC) supported pressurized LH2 testing of the initial smaller 2.4 meter (~8’) tank last July.

Small tank test, July 2013

This year, MSFC will test the 5.5 meter (~18’) tank, which will be flown in from Boeing’s Seattle facility on the Super Guppy.

Artists Rendition of the 5.5 Meter Tank

Super Guppy- the aircraft that swallows space ships.

This tank will endure more than mere pressurization with LH2. MSFC’s Special Test Equipment Branch (ET50) is designing a test apparatus to apply a combination of compression, moment, and shear loads. The final test is to failure. The test will take place at the 4699 facility, visible on Google Maps at https://www.google.com/maps/@34.6284812,-86.6728124,135m/data=!3m1!1e3

Test stand 4699: Upper load spider is sitting on the ground next to the test stand. The lower spider is barely visible in the center bottom of the test stand, where it is in shadow. The shear towers are at upper right and left corners of the test stand, slightly taller than the rest of the stand.

My job is to make sure the failure occurs in the test article, and not in the structure applying the enormous test loads. I am a member of ET50’s in-house stress analysis team. I broke down the test apparatus into more manageable parts, and created Finite Element Analysis (FEA) versions of each, using plate models. These analyses give a very accurate picture of how the structure will react under the test conditions, and allow me to advise the design team early on if there are any potential issues that need to be addressed.

The test apparatus is composed of upper and lower “load spiders”. The test article will sit on the pads of the lower spider. The upper spider will be supported over the test article by a large pedestal structure. Sixteen load lines will push and pull between the top of the test article and the bottom of the upper spider. In the FEA contour images below, the hardware is depicted reacting to a complex loading. Deflections are highly exaggerated for clarity- the beams will only move about .13 inches. Two shear towers sit on either side of the setup, with the shear beam spanning them. Two additional load lines attached to the beam impart a shear load into the side of the test article. The upper spider is about 33 feet in diameter, for reference.

  

Upper Spider, on top of Pedestals

Shear Tower

Lower Spider

Shear Beam

Update: The tank is at MSFC http://swampcastle-scrapbook.blogspot.com/2014/03/the-cryo-composite-tank-has-landed.html

Recent Test of the Gas Generator from the Saturn F1 Engine

The joy of smoke and fire, from a test stand I helped analyze. J Below is a photo of a test of the gas generator off of a vintage F1 engine. There's more info and a video on the NASA website.

Here's a photo of the surface that the flames are shooting across, actually taken before the test.

Below is a photo of the test stand being modified for the test, followed by a screenshot of the model. There isn’t much room to move around, with all of the piping systems twisting around the structure, test article, and each other.

Here is a section of the LOX system, followed by analysis of the new LOX support structure.

Last Discovery Mission

This is a picture of Discovery's last crew, STS 133, with everybody's signature. Discovery carried my EVA tools all those years ago, and the final mission is the one that I supported with the test fixture analysis. The fixture was for testing to support the repair of the external tank stringer, which cracked during tanking.

Snoopy

I never thought I'd get a Silver Snoopy! And my good friend got one at the same time, making it that much more special.

TBE Article
Marshall Star Article
NASA Awards Database

Closing the door.

In my earlier post, the shuttle scaffolding was being removed from the Dynamic Test Stand to make room for Ares I.

They have completed the removal process.

Looking down from the top floor.

 Looking down from mid-building

 Looking across from mid-building

Looking up from mid-building.`

Ready to be outfitted for Ares I...

Closing the door, prepping to put the roof back on.

Sadly, they have now closed the door back on an empty test stand. No rocket in the building. I hope we'll have one to test some day soon.

Stringer test fixture

These are photos of the hardware that was the subject of the stress analysis that I posted about, below.

Photos of the stringer test fixture.

Salute to Discovery

This is my salute to Discovery, with a vintage 1960's Astronaut Snoopy and my mission cup from Discovery's STS-51 in the foreground, and one of the big test stands out my office window in the background. Snoopy is somewhat worse for wear, because he was a gift from my father, and my brother and I enjoyed him as kids.

FEA of Stringer Test Fixture

Here are some clips from a stress report I collaborated on. The hardware was designed specifically for the ET-137 Intertank that flew with STS-133. The fixture was used during the effort to repair and qualify the tank for flight, after a fracture was found in the stringer at the rivet line.

Hardware description:

This test fixture is designed to test a one-stringer section of STS External Tank panel under loading conditions similar to those experienced during tanking. The simulated loads are experienced when the bottom of the tank contracts under the cryogenic thermal load, but the top of the tank is at ambient temperature. This fixture uses mechanical means to deliver the simulated load without applying any actual thermal load to the test panel. The loading is intended to cause cracking in the stringers similar to that of the flight article. 

Common Bulkhead test Rapid Prototype model

Here's a desktop-sized rapid prototype of our test fixture. It is made of plastic, and painted. The actual fixture will be about 20 feet across.

This is the Common Bulkhead sandwiched between my barrels. You can see the barrels in the above assembly, where the Upper Dome covers the Common Bulkhead.

Ares 1-X

A nice shot of Ares 1_X on launch morning. This is the one with a live first stage, and dummy upper stage and booster. The fisrt stage is made of five SRB segments, which makes it the longest solid rocket stage used to date. The shuttle SRB's are four segments each.

Common Bulkhead Test poster

This is a poster I made, using the Pro/E models of our designs. It's of a test fixture we're designing for testing the ARES I common bulkhead. The common bulkhead is a dome that will serve as the top of the LOX tank, and the bottom of the LH2 tank.

Ares photos

Here's a link to some good photos, and ARIES I stackup time-lapse for the first-stage test, with dummy upper stage and dummy Orion.

Cool shot of an engine test

They tested the launch abort motor in Utah. I like the four distinct plumes. Here's the article, with some videos too.

Shell Buckling

This is from my first project at TBE/NASA. I used some of my real-time modeling skills to make the CAD models look more realistic. The test article, lit so brightly that it looks like a warp engine, was a scale version of a rocket skin, and built with greatest care. Then, we squeezed it until it buckled with a wonderful boom, all in the name of science. They got some very good data from it. Here's an article about it. I call it the "Can Crusher".

They have buckled a second and third article, with plans to do more. We may also build another one of these, twice the size, without the brown towers.

My poster, rendered from my Pro/E model.



The actual article, built from my prints, all ready for the first test.

From Swamp Castle

Focus on Marshall video

Cool! My test is in Focus on Marshall, episode 31, November 2008! Mine is the shell buckling, which they talk about in the video, after the ullage motor bit. I guess I didn't rate for the interview, but whatever. Fist test may be tomorrow!

Shuttle Photo

Two Shuttles ready for launch to repair the Hubble Space Telescope in October.

MSFC Dynamic Test Stand Photos

Here are some photos Bryan took the day we went up on the dynamic test stand, and then spliced together later. In these photos, the floor is still configured for shaking the shuttle "Enterprise". You can see roughly shuttle-shaped holes in the floor, where it was suspended.

They are currently removing the shuttle floors, and will be reconfiguring to hold ARES I. This tower is one of a pair that make a familiar part of the Huntsville skyline. Until recent years, it was the tallest structure in Alabama. The view from the top is awe inspiring.

The crane on top, as seen from the roof:



Looking down from the roof, through the open door.



At the level of the door threshold, looking up at the roof crane.



Looking across the door opening. Looks like the door is 7 floors tall. Here you can see that the bottom of the doorway is still pretty high above the ground.



Looking up, you see the side of the test stand, then the door slid down, then the door opening, and the cranes on top.



A shot from the inside, looking at the layers of walkways.



Looking down through a shuttle-shaped hole.



Imagine slipping a shuttle, nose first, down through this hole.