Low Quality Alloy Cause of Shuttle Main Tank Issue

BJ_Covert_Action writes "NASA engineers have finally discovered the root cause of the cracks that have been found on space shuttle Discovery's main external tank. The main tank, one of the 'Super Lightweight Tank' models developed by Lockheed-Martin, employs an aluminum-lithium alloy developed by Lockheed-Martin specifically for this application. The new alloy is used in various structural stringers throughout the SLWT design. Unfortunately, the batch of this alloy used in the tank that is currently mated with the Discovery shuttle appears to be of low quality. The alloy used in the stringers has a 'mottled' appearance, compared to the nominal appearance typically used in the main tank stringers (see picture in article). This appearance is indicative of a fracture threshold that is significantly lower than typical. NASA has determined, through testing, that this low grade alloy has only 65% of the fracture strength of the nominal alloy typically used. NASA engineers have devised a potential fix to the problem that they are currently testing to ensure the repair will cause no unintended consequences. NASA plans to have the Discovery shuttle ready to launch again by February 24th, 2011."

Re:Typical U.S. quality

[dadelbunts]

Not typical U.S quality. Typical U.S government contracts. Government agencies opt for cheapest price instead of quality usually. I remember when COD4 came out i was working on some contracts for the army and i saw this quote. Could never keep myself from laughing at how true it was. “Never forget that your weapon was made by the lowest bidder.”

Look in the mirror.

[Anonymous Coward]

That's the Government's stupidity for not putting a performance clause into the contract

And you know that because...?

I work as a QA engineer for a large defense contractor. One thing I can tell you is that we issue a lot of documents requiring our plants and our suppliers to follow a metric shitload of MIL, ISO, EN and whatnot standards, for the very purpose of meeting stringent quality requirements set forth in the contracts. It takes months, sometimes years for our products just to pass qualification and type-approval tests, and our products don't even go in space.

In short, you're talking out of your ass.

And yet, shit still makes it to NASA and to the military.

So, who's talking out of their ass again?