In a message dated 9/6/2007 5:21:27 A.M. Pacific Daylight Time,
towertalk-request@contesting.com writes:
> Wait a second. I'm trying to understand exactly what it is that is so
bad.
> I see the bending of the erection fixture, not good at all; is that it? I
see that 90 ft is waaayy toooo much for this erection at least with this
fixture. A heavier version of the same thing would have been much safer.
> However, whoever said there weren't any guys I believe made a mistake.
This
looks to me like a variation of the standard "falling derrick" method I
think it is called and yes, there are guys, 4 sets of them.
No, this is not a falling derrick. It is just a tilt-up fixture pulling it
up.
Yes, there are guys attached to the tower but they are just hanging
there with NO ONE hanging on to them. All that's holding the tower vertically
is
whatever their hinged base is and the line attached to the tilt-up fixture.
> One directly
off of each side, perpendicular to the lifting direction, tight the entire
time from the horizontal position to the vertical orientation. One in the
direction being pulled, slack during this operation, and one directly away
from the lifting mechanism, also slack until the tower is very nearly erect.
If the cable(s) break and it falls, it can only fall exactly where it laid
before it was lifted. With one excepting and that is hard to discern, I do
not see anyone "under" the tower after they get it walked up to the point of
release (probably not good because of the weight of the tower, although they
DID lift it to get it started so if the cable would have broken while they
were under it, they were lifting the "entire" weight of it anyway and could
have just laid it back on the ground).
Sorry, I didn't see anyone doing anything with the guys in the video.
That's the problem. Even having people hold the guys is problematic. If one
person pulls just a little more than the other two, he'll pull it down in that
direction.
Cheers,
Steve K7LXC
TOWER TECH
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