That is commonly called the 'falling derrick' method of raising a tower.
One description of how to do it:
http://www.n6rk.com/falling_derrick_gme/falling_derrick_gme.html
Note that the pole in this case is not usually called a 'gin pole' since it
moves and does not usually have a pulley... a derrick is a more proper term
for a movable support like that. A gin pole is more commonly a pole with a
pulley at the top that is used to lift sections vertically up a tower, then
moved up to the top of the section to pick up the next one. you can also
use a gin pole to raise a tower from horizontal, these are often supplied
with crankup tilt-over towers, but the pole in these cases is fixed in a
vertical position with a pulley at the top that pulls the tower up to it
with a winch (or is it wench?).
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Donald Chester
> Sent: Saturday, August 11, 2007 17:51
> To: towertalk@contesting.com
> Subject: [TowerTalk] Erecting a tower with a block-and-tackle and gin pole
>
> I recall reading an article in a pre-WWII radio publication about raising
> a
> 100-ft tower entirely with a gin pole, requiring no climbing or crane.
> The
> tower was fully assembled on the ground, and the guy wire lengths were
> precisely calculated using a transit level, and cut to length. Two sets
> of permanent guys were connected to their anchors, while the third set was
> left unattached. A temporary set of guys was attached to the tower and to
> the top of a rigid pole, which was then hoisted to a vertical position. A
> couple more temporary guys were attached to the top of tower, anchored 180
> degrees apart.
>
> The tower was now lying on the ground, with the rigid pole (about 1/3 the
> tower height) in a vertical position, at a 90-degree vertical angle from
> the
> tower. Using a block-and-tackle arrangement, the vertical pole was slowly
> pulled down to a horizontal position, which in turn hoisted the tower to
> the
> vertical. Once it was fully vertical, the remaining set of permanent guys
> was attached to its anchor.
>
> Only after the permanent guys were fully attached and given the final
> adjustment and the tower plumbed, someone climbed the tower to detach the
> temporary guys and install the antenna.
>
> I believe this same technique was used by the Signal Corps to quickly
> erect
> towers under battlefield conditions during WWII.
>
> Don k4kyv
>
> _________________________________________________________________
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