Seems it was wire rope, 3 cords of 7 strands of wire (total 21). Two
strands of wire were broken, I would think by an impact. I wonder how much
trouble they'll have extending them again, and if plans will change to
have astronauts assist opening and closing of arrays.
Wire clippers not WD40. Preferably fingernail clippers.
Pure speculation, couldn't find a drawing.
Sure sounds like the grommets are getting stuck on broken strands of wire
of a wire rope, if that's what the grommets are sliding on. Some sailboats
have wire rope halyards. Wire rope is different from wire cable in that
the individual strands of wire within the rope are very thin. This makes
the wire rope very flexible, unlike wire cable. When these become old,
individual wires in the rope will break. The wire rope is still fine, but
if you rub your hand along the rope, you'll make a bloody mess. The broken
wire strands are sharp, stick out a bit and will snag anything.
Also, sounds like the wire rope is being wound up on the opposite end from
where the solar panels are being folded. The grommets would have to slide
many meters instead of a few centimeters.
Also, if they did use wire rope, they may have just as much trouble
unfolding it because of the other end of the broken strands.
On Sun, 17 Dec 2006 07:57:11+0000, Brian Gaff wrote:
Well, it looks like someone needs to do some work on designing solar array
mechanisms..: I mean if you have to stand over them after 6 years and wiggle
them every so often to get them to not stick then...:-)
I hope someone has a plan of exactly what can be done in future, as there is
another array they will need to stow before moving the truss, I think.
Send out a can of WD40?
