[TowerTalk] Crankup tower safety question... (Crankup

[Grant Saviers]

My thinking about locks - every item has a failure mode and locks are no 
exception.  What if the lock won't disengage or worse snags with the 
tower up or partially down?  How does one safely disengage the lock with 
the tower weight on it and perhaps the pull down cable also tensioned?  
Would you climb that tower?  Rent a bucket truck or boom lift and work 
under the antennas that could come down on you? (boom lifts go to over 
100' so removing all antennas first is probably an answer).

It seems to me that locks create another complex set of trade-offs. Well 
maintained cables and winches are one answer, but stuff happens even 
then.  Maybe a simple redundant or "safety" cable would be a better 
alternative.  Then one more item to maintain and fail.  An inertial lock 
like safety belts if the tower descends to fast? (loop to the above issues).

OTOH, I think Luso and I know Will-Burt make locking mechanisms for 
their towers and tallest pneumatic masts, respectively.  Anyone know how 
they work?  How you get the tower/mast down if a lock fails?

Grant KZ1W
I own 4 crank ups & 2 Will-Burt masts

On 8/2/2013 5:41 AM, Jim Thomson wrote:
> Date: Thu, 1 Aug 2013 20:13:45 -0400
> From: Mickey Baker <fishflorida at gmail.com>
> To: "towertalk at contesting.com" <towertalk at contesting.com>
> Subject: [TowerTalk] Crankup tower safety question... (Crankup
> Danger!)
>
> Patrick, AF5CK's thread on his tower raised an issue that I really don't
> understand...
>
> Why isn't there a "lock" mechanism on crank up towers?
>
> We spend lots of money on these things, and, basically, they hang there
> suspended by a single cable. We all have either known someone or have had
> our own tower's cable (or winch) fail and the tower crashes, with great
> damage to tower and antennas.
>
> I could thing of a number of gadgets that could be made to work:
>
>     - A solenoid locking bolt
>     - A brake mechanism (Electronically controlled?)
>     - Stops every few feet requiring a raise then lower like a safety ladder.
>
> But here I am, about to step off into yet another $10k tower project with
> another tower hanging by a cable. (I feel like Homer Simpson - Doh!)
>
> I realize that the market is small and price sensitive for these towers,
> but certainly this has been recognized as a problem.
>
> Isn't there a better way? If there is, and I can implement it, I'd do so,
> simply for the purpose of making the tower safer for me and my antennas.
>
> Thoughts?
>