This is an extension of the 90' tiltover discussion,
where the guys were dangling as it went up.
Two things to point out:
1) W3GM used a falling derrick method on his 100' 25g's,
with 4 way guying. The back guy was attached to 40' of
25g, which was siezed off to a concrete guy anchor/deadman.
Tower lowering was achieved by a winch driven by a 1/2" drill,
between the deadman and the back-guy section of tower. With
4 way guying, it was stable all the way up. getting the side guys
matched is critical.
2) I had an ab621 launched-mast for several years, and used the
dangling guy system to 70' effectively. That is, the launcher base was
securely guyed. Then, the tower pushed up from the bottom, with guys
attached at the 60' level. If there was no wind blowing, I could put
the tower up to 70' without touching the guys...then simply walk around
to the guy anchors, and take up on them progressively, until things
were solid. Did this single handedly, many times, with a th6 or a
2 el 40 on top. The weight of the guys, and rigidity of the structure
held things nicely in column.
My point is, while safety is paramount, creative thinking shouldn't
be discarded. Watching the 90' erection, I found myself wondering
"What the hell were they THINKING?".
And, I've halfway been expecting someone from that group to pop in here
and say, "You know, we've been doing that with that tower for the past 22
years.
Works fine." Looks awful, but you never know.
n2ea
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