An “Uh-Oh” Moment at 120 feet

Well, into every tower worker/climber’s life, a little excitement can creep in, just to keep life interesting. This Monday, for W2GD and myself, that happened in the Catskills. We were removing and then lowering the non-functioning OptiBeam OB 18-6 for N2QV. This seemed, looked, and was considered a tricky proposition, due to the sheer size and weight of the beam, and the fact that it was mounted on a length of 2.25-inch water pipe. Water pipe, as many readers may know, really isn’t rated for carrying loads (it’s intended to funnel fluids from one point to another, that’s it). So while we were apprehensive, we went ahead anyway, as daylight disappears at the end of the day, ya know? (Mistake #1)

N2QV’s tower site was literally cut out of the woods, so the back guy was going to be particularly difficult to position. For that reason, we went with rope (Mistake #2). For the tram, we of course used 3/16-inch EHS. As the beam uses a slightly-larger-than-3-inch square boom, the antenna needed to be lifted UP and then OFF and OVER the tower’s flat top plate. So, considerable rigging was done to accommodate that setup.

All went fine. The beam came up, we slid it out, and began to lower it slowly, working at getting the elements past the top guy set. The mast (which I was watching) was quivering a bit, but seemed otherwise to be okay. The beam cleared the top guys and we stopped for a moment. Then, two of the bolts holding the mast inside the TB-4 thrust bearing simply exploded out of the aluminum housing—shooting out over my head, with the mast then slamming against the bearing shell, And then it quickly bent over. Of course, at the time, this seemed to take about half an hour, but it was literally over in likely less than two seconds. There was a fair amount of shaking up there, along with some profanity, but I digress…I’m here writing so nothing totally untoward happened. The beam finally stopped shaking. Once we did too, our only option was to continue lowering it, which was compounded by the lowering rope’s being wrapped around the guy bracket bolt, and the back guy rope now be stretched over the tower top. Again, we lucked out and got the beam on the ground without damage. Securing the mas against catastrophic failure in our absence (the water pipe did not crack, surprisingly, simply bending), we climbed down & thanked whatever personal deities we each believe in for sparing our lives.

The remainder of the day was spent repairing the OB-18-6, which went well. A new 2.5-inch chrome-moly mast has been ordered. The next exciting detail will be sawing apart the bent water pipe at 120 feet and then lowering it (water pipe, while weak, is heavy!). This may be the most expensive OptiBeam installation ever accomplished! Three cheers to Tariq, N2QV, for his dedication and perseverance.

Home after 12 hours driving through the rain.

stay tuned…

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