Forgive my ignorance, but I need some clarification on your
clarification. Describe exactly what a 'forging lap' is. What do I
look for when inspecting a blade? Can it be seen outright, or is an
X-ray necessary?

Also, I thought that composite blades still used a metal spar. Is
this not correct. If not, please describe their construction.

Dennis.

"Bob" wrote:

I WAS THE CHIEF INSPECTOR FOR TRUMPS HELICOPTER OPERATIONS AT THE TIME SO
YOU CAN TAKE THIS INFO TO THE BANK. HIS AGUSTA 109 WAS IN MAINTENANCE THAT
DAY AND WAS UNAVAILABLE. THE BLADE THAT FAILED HAD A "FORGING LAP": LEFT IN
THE M/R/B SPAR SINCE MANUFACTURE WHICH CREATED A "STRESS RAISER", EVENTUALLY
A CRACK, AND THE REST IS HISTORY. For the rest of the commenters, now with
many composite blades out there a better record can probably be expected
although no great inspection methods have yet been developed for composites.
Metal blades departed aircraft many many times, hence Sikorsky's "BIM"
indicators on the blade roots. Hundreds of thousands od pounds of
centrifugal force and cracked blades will always present a problem, huh?





Dennis Hawkins
n4mwd AT amsat DOT org (humans know what to do)

"A RECESSION is when you know somebody who is out of work.
A DEPRESSION is when YOU are out of work.
A RECOVERY is when all the H-1B's are out of work."
To find out what an H-1B is and how they are putting
Americans out of work, visit the following web site
and click on the "Exporting America" CNN news video:
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