Shuttle Foam Test Yields Hole in Wing (Produces vs Yields)

AP ^ | 07/07/2003 | MARCIA DUNN, AP Aerospace Writer

[DoughtyOne]

Science - AP

Shuttle Foam Test Yields Hole in Wing

59 minutes ago

By MARCIA DUNN, AP Aerospace Writer

SAN ANTONIO - The team investigating the Columbia disaster fired a chunk of foam insulation at shuttle wing parts Monday and blew open a gaping 2-foot hole, offering dramatic evidence to support the theory of what doomed the spaceship.

The crowd of about 100 gasped and cried, "Wow!" when the foam hit.

The foam struck roughly the same spot where insulation that broke off Columbia's big external fuel tank during launch smashed into the shuttle's wing. Investigators believe the damage led to the ship's destruction during re-entry over Texas in February, killing all seven astronauts.

It was the seventh and final foam-impact test by the Columbia Accident Investigation Board, and it yielded by far the most severe damage.

The 1.67-pound piece of fuel tank foam insulation shot out of a 35-foot nitrogen-pressurized gun and slammed into a carbon-reinforced panel removed from shuttle Atlantis.

The countdown boomed through loudspeakers, and the crack of the foam coming out at more than 500 mph reverberated in the field where the test was conducted.

Twelve high-speed cameras — six inside the wing mock-up and six outside — captured the event. Hundreds of sensors registered movements, stresses and other conditions.

NASA (news - web sites) will continue gathering more information about the poorly understood pieces that line the vulnerable leading edges of shuttle wings, board member Scott Hubbard said.

One month ago, another carbon shuttle wing panel — smaller and farther inboard — was cracked by the impact, in addition to an adjoining seal. This time, the entire 11 1/2-inch width of the foam chunk — rather than just a corner during previous tests — hit the wing, putting maximum stress on the suspect area.

[snopercod]

Kinda' like a punkin' chucker?

[snopercod]

Once again, NASA supported the RCC sections with glued on external struts. You can see them in all the pictures.

Why are they doing this? Are the RCC sections not attached via their normal hardware, or are they trying to protect the normal attach hardware because it is a known weak point and would fail in these tests, blowing away the entire RCC section?

[eno_]

I recall a Freeper making an estimate it was around 500mph relative velocity, based on frame-rate of the high speed film.

[eno_]

At the speed the shuttle was moving, a 500mph relative velocity is a small perctage of the shuttle's speed, and, IIRC, the shuttle was still accellerating at that point.

[eno_]

The shuttle was on main engine and booster power. So an aerodynamic flaw on the shuttle would be readily compensated for.

[Darksheare]

Whoever it was, it's still a riot.
But the guy who related it to me had said the French were the guilty party.
But it matters not, it's still a darn good story.

At the time I had chalked it up to being a "pilot's story" except that it didn't begin with "There I was" or "No S**t!" like the normal stories from former soldiers.

I find the darn things design itself interesting, a round 'gun tube' that can launch a non-round chicken to 500 miles an hour or so. I'm guessing that's the same type of 'gun' the used to launch the foam at the shuttle wing section.

[DoughtyOne]

Thank you. That was a nice simple explanation. I fully understand now. I probably should have for XBob, but for some reason I just didn't understand what he was trying to say.

[DoughtyOne]

BTW, I'll try your site again.

[DoughtyOne]

Thank you. Wish I could take credit for it. I'm just passing the info along. I am glad you found it interesting.

[XBob]

76 - "Budge's graphics" wouldn't load.

they are graphic images, not videos. click on the graphic pictures and a larger version will appear.

[DoughtyOne]

Thanks for the directions. The problem was, the page stalled before any icons came on the screen. I had to kill Netscape twice just to regain control.

[XBob]

sounds like you have too many things running in the background on your computer.

get to a stopping point, where you have everything you need to have saved, and hit CTL-ALT-Del, and a list of what is running will come up. If you have Win98, there are only 2 programs necessary to be running in the background.

If you clean up your computer, it will run a lot faster and better.

a good site to go to is :

http://www.mycomputershow.com/

Ira Wilsker is excellent, and following his directions on cleaning up your startup will make your computer run markedly better.

[El Gato]

Thanks for the link.

It looks to me like the impact is on the RCC leading edge treatment. Just as in yesterday's tests.

[El Gato]

Kinda' like a punkin' chucker?

Only sort of. It uses compressed nitrogen as the "propellant", not some combustable gases, In that way it's more like a giant paint ball gun.

[El Gato]

Once again, NASA supported the RCC sections with glued on external struts. You can see them in all the pictures.

Are those supports, or an attempt to simulate the aerodynamic loading that would be present in flight? They look to me as if they would push on the RCC section, not support it.

[El Gato]

I'm guessing that's the same type of 'gun' the used to launch the foam at the shuttle wing section.

Yes, it is. The SwRI gun used in the tests is one modified from just such a Chicken Gun. The group which does the tests for NASA has long been involved in doing such impact tests on various structures.

[Resolute]

"I find it hard to believe that the foam slowed down enough to go from a delta-V of zero to 500 MPH in the short distance involved. Then again, it's hard to say without knowing the air density, shape of the chunk, and so forth."

We examined that from a physics / math perspective here . . .

Observation on TPS damage on Orbiter (Post 2440)

Observation on TPS damage on Orbiter (Post 2445)

[Resolute]

"Do you have the math to show a 500 mph relative speed?"

See the links at reply #97, this thread.

[Darksheare]

That's gotta have alot of volume of air/nitrogen or whatever they're using to be able to launch a non-tube conforming 'round' out of the tube.
Has to be an interesting design.

[Resolute]

The math supports what you said.