Tin whiskers causing Boeing 787 problems?

Question

Just read this statement from a Boeing engineer:

"Sinnett, the 787?s chief project engineer, said that in each of the power-panel incidents electrical arcing inside a circuit board ? ?a low energy arc that lasted milliseconds, very small? ? had damaged the board and shut down some of the plane?s electrical power.

He said the small spark inside the circuit boards produced no safety hazard, only a loss of function that was handled by the plane?s multiple, redundant power systems.

In January, Boeing had not yet found the root cause, but Sinnett said the problems had been traced to a batch of faulty circuit boards inside the power-distribution panels, which are located, like the batteries, inside an electronics bay.".

Faulty because they use lead-free solder and the Humiseal didn't stop the growth of the tin whiskers.

Paul

Michael A. Terrell · Accepted Answer

The Aerospace industry is exempt from lead free solder for just this reason. Medical & Telcom are exempt, as well.  That's because the Belgian bureaucrats knew it is crap and will cause failures.

Paul Drahn · Answer

Yes, that is true. We build several circuit boards for aviation oxygen systems using leaded solder.

However, both Boeing and EADS decided early on to use lead-free solder on their circuit boards. I attended a seminar in Beaverton, OR before the lead-free requirement went into effect. One session was sponsored by Boeing and a couple of their engineers and board builders told how they were using lead-free solder on boards for a new version of the 747, and it was company policy to use lead-free on all future airplane builds. Eads did the same and this is why they had so much trouble with the A380, etc.

At the time Boeing's problem wasn't tin whiskers, so much, it was mainly having the components pop off the circuit boards during the standard vibration tests.

Paul

Stormin Mormon · Answer

Environmentally friendly. When the planes crash, no lead pollution.

Christopher A. Young Learn more about Jesus

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At the time Boeing's problem wasn't tin whiskers, so much, it was mainly having the components pop off the circuit boards during the standard vibration tests.

Paul

Cydrome Leader · Answer

exactly.

Stormin Mormon · Answer

It's for the children. No lead pollution. Christopher A. Young Learn more about Jesus    . Stormexactly.

Michael A. Terrell · Answer

Lead free solder is pure crap.  It grows whiskers, it's brittle and it's weak.

Spehro Pefhany · Answer

Yabbut you can spread lead-free solder paste on your toast for breakfast and not get ill.

Paul Drahn · Answer

All true, but still 60%of our business and growing! The worst is the  fumes from the flux needed to hand solder the through-hole components. Paul

grmiller · Answer

I would much ather have ginger marmalade.

Michael A. Terrell · Answer

Not me.  I gave up metal for breakfast.  The flux would do more damage, anyway.

Michael A. Terrell · Answer

We were exempt at my last job, building equipment for NASA. The only problem we had was the local fire department insisted on a vent fan near our solder pot, which made it difficult to maintain the proper temperature.

Tin whiskers causing Boeing 787 problems?

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