"Robert11" wrote in message
news
Hi,

b. Any info on the newer, I think, types of hold-back mechanism that do
not utilize the breakable bar, but apparently use some type of captivated
spring/cam mechanism as part of the bar (permanently) ?

Thanks again,
Bob

Yes, they're called RRHAs (Repeatable Releasable Holdback Assembly). They're
a one-piece bar that fits into the back of the (A/C's) strut and on the
strut there are two metal plates that sandwich the holdback bar. In order to
launch, the bar must have enough force applied to it for it to slide past
the metal plates/springs. It's basically like some cabinet doors that have
the little pokey thing that have to slide inbetween two springs in order to
open... they come in different shapes and sizes for different airplanes so
they don't get one with the wrong-sized "fist". Since nothing breaks during
launch, they can be reused. They just have to be inspected every once in a
while to make sure there's no stresses inside the bar that might make it
break, and also to make sure the fist hasn't worn down too much.

Jason