The Tower Day From Hell - How I destroyed my log

[K1JJ]

We all have them. Days when things go very wrong. Read and learn what not to do....

Background:  I planned on taking down two log periodics and rebuilding them into two 20M Yagis and two 10M Yagis. I took down the smaller 200 pounder at 60' a few days ago. Smooth.  Today was planned for the big one at 100', 400 pounds. It's a Big Bastard.  Rohn 45 100' tower.

I work alone, so it takes a lot of tower climbing. The usual plan is to put a tram line at 45 degrees from the top of the tower to the ground. The log rides down on a pulley and is controlled by a second rope and pulley called the control rope.  The tram line is 4,000 pound test guy cable and the control rope is 1200 pound test polyester or some shit rope like that.

I climbed up to 100', ran the tram and unbolted the log. Back down to tighten the tram on the ground and set up the tractor with the control rope. Back up top to release the log - then back down.  Now all set to drive the tractor to slowly let it ride down the tram.  NG. The control pulley wasn't working up top - log stuck. Climb back up and realized it was the TRAM pulley that went off track and the tram cable was stuck in the pulley big time.

Back down to release the tram and get a come-along to pull up the log and fix the jam. Climbed back up and released the jam. Now the come-along gets jammed with a roller cable turn on top of itself - know what I mean?  Back down to get a second come-along to release the first. Back up. [100' - getting very tired now]  Released the come-along, everything FB, ready to drive the tractor and let her slide down. Very careful to make sure everything is strong and rigging OK.  Is that six climbs for a two climb project? I lost track and I'm sore as hell.

Back down. Sun going down. Start tractor and log slides down slowly for about 5'. FB, OM. Then all of a sudden I hear a SNAP!  The log appears to be falling down the tower! Happened very quickly. Actually, the control rope broke and the log slid down the tram line at 900 mph and one half of the elements  jammed themselves into the ground. Prezell logic, OM. 

I ran over to check it out and found the control rope had broken in the MIDDLE of the span, not anything to do with pulleys, friction, etc. Strange.  I lost at least 1/3 of the total aluminum.  Every one of 14 elements on one side of the log was bent, but only about 1/2 of each el. The other side was OK.  The boom was OK too. Guess the bent elements cushioned the crash into the ground.

I was yellified, but was kinda happy that rope didn't break when I was up there doing the last preparations and in a vunerable position. So why the hell did it break? The tension on the control rope had to be less than 200 pounds on a 45 degree tram line. It was 1200 pound test. I looked it over and think that maybe it was weather beaten from UV, as sometimes I left it up there for a month or so. Or maybe rotted, dunno. Being 600' long I should have used the OTHER end that was almost unused.  Then again, I usually used my 2,000 pound nylon rope for this particular heavy log, but that rope was being used on another tower and wuda meant another climb... sigh.

So, guess the lesson to be learned is to CHECK over your ropes, OM. It's really a blessing this happened like it did, without injury. I can pick up some more aluminum and fix these elements no problem, but it would be a real pisser if that log dropped on MY log.

T

[W2VW]

Not so FB OM. Screw the antenna. You can always replace it. Just be glad that you don't have an Aluminum pipe through your skull ala Steve Martin. Sometimes it's good to work with someone else even if they are a putz.

[K1JJ]

Not so FB OM. Screw the antenna. You can always replace it. Just be glad that you don't have an Aluminum pipe through your skull ala Steve Martin. Sometimes it's good to work with someone else even if they are a putz.

Yeah, it makes it easier to have a ground crew, no doubt. But with imagination, it can be done safely solo too.   

I think that rope wuda broken no matter how many were helping and could have kissed someone on the ground to boot... yikes. Rather I commit suicide than take others too...

Yep, aluminum is EZ to fix. 

What keeps me motivated is the great exercise. Can't drop pounds this fast any other way...

T

[Jim, W5JO]

Wow Tom:

Keep in mind your safety.  I had a Lineman's leather belt that I brought with me down here.  I had the belt for many years and each time I inspected it before the climb, then put it on and attached to a cross member to put my full weight on it.  Over the years I had oiled it and cared for it.

When I got ready to put the last two sections of tower up here, I put the belt on and attached to the cross member.  When I put my full weight on it, it snapped in back.  Had I been on the tower, well you know.

Vry Sry about the Log, but you are not replaceable.  Thank goodness you are OK.

Jim

[K1JJ]

Hi Jim,

Boy that was close with your leather belt.  I should do the same thing - a test at ground level with the belt. Never thought of that.

I've heard the same thing about leather getting old and breaking. I have one here that I don't use anymore. Those waist belts can be quite dangerous and break a back - a few years ago I changed over to a new full body harness, all nylon. What a pain to put on, but I love it.

Yes, safety is what I think about all the time. I'm out there climbing almost every nice day in the summer.   I try never to get lax... always on the alert for stupid mistakes.  But, failed equipment is a tough one. Gets the best climbers sometimes, unfortunately.

T

[W2VW]

Where are the pictures?

[K1JJ]

Where are the pictures?

Maybe I should take some tmw before I tear it down.

After it happened, I couldn't stand looking at the mangled elements all twisted up, so I cut them off with the saws-all and put them in a pile. But the rest of the log sits there with amputated arms on one side. Should be a funny shot.

It would have bothered me more if I had just built it and it was going up for the first time, but aw heck, it's being used for parts anyway, so just gotta mix and match a little more....

Thinking about it tonight, this is the first mishap since I started this antenna/tower stuff in 1986. Been pretty lucky so far.

Except for some minor tower cleanup work, I get to work on the ground for the next coupla weeks or so. Shaefer time, caw mawn.

T

[Steve W8TOW]

I'd check all guys and inspect the tower carefully on next climb....
I've only worked on a few Rhone 45/55's (most my tower work was
done on Pyrod self-standing towers, but...
man be careful! don't need a SK among us...vri 73steve
8tow
(ps, first tower job story:
taking down a Pyrod 70' using a gin-pole.
All sections rusted ...using a saws-all to cut legs. 3 man crew, 2 on tower...
Frist section, no problem. Second section, no problem.
Re-position gin-pole, cut leg 1, then leg 2, and decided I would move
over to opposite side of tower...just as I snapped in,  ready to cut final leg,
the gin-pole doubles over, tower section falls exactly where I had been!
After changing of shorts....back on tower, and with pullys in place, lowered it down..
That was in 1989...after that, my little tower company and I removed 15-16 Pyrods in central Indiana, all 80"-120" and never used a gin-pole ever again. We sub-contracted
a crane out fit to assist...no more tower mishaps....)
dit dit dit dah

[Jim, W5JO]

These kind of stories are scarey.  I, too, went to the full body harness with the nylon lanyard to help prevent on the tower injuries if I fell.  There is an old story that as we age, we become more conserative in our money, politics and our risk taking.  At 62 I am almost through climbing towers.  Mine is 40 ft which has become my limit since I don't have to do it for a living any longer.  It is more than a quarter wave above ground for 20 meters and the tower is self supporting so I don't have guy wires to hang on things that go up.

A friend of mine has one that he lowers by cable to work on his antennas.  He started down with it one day and the cable came loose from the winch just as he started down with the tower.  It fell and ruined not only his antenna but his fence and an out building.  Anyone who thinks they can dodge this type of thing really does not understand how fast accidents happen.

Post some pics of what you have left Tom.  Maybe it will be a good reminder to everyone what can happen.

[Bill, KD0HG]

I don't think they make lineman's belts out of leather any more...
I bought a replacement from Grainger a few years back and it was made from nylon webbing with only a bit f leather sewed in for tool loops.

Leather horse tack gets weak and starts breaking after a few years.

I wouldn't bet my life on a 30+ year old belt, no matter how good it might look.

Glad ur OK, Tom. Take care!

[WV Hoopie]

Tom,

Glad to hear that no one was hurt! Safety is #1 in all that we do. Please do post a few pics of the incident so others can learn from the accident.

At work, (when I worked) we always had to wear a safety harness and lanyard if over 6 feet above ground. Pipe racks, cable trays, man lifts, etc. didn't make a difference; gotta have a harness and lanyard. Double lanyard when walking the racks and trays so you were always tied off, can't be too safe. The company and OHSA required periodic inspections of the harness and lanyards, stickers to be attached so users knew they had a piece of PPE that could be trusted.

I'd place tower/antenna work under the classification of rigging. It is another ball game most are not qualified to perform. Can't beat a man/woman at their ballgame. Be honest with yourself, if you don't have a clue or need help, stop!

Any of the facilities visited within the company I worked for; I always preached, "The goal is to get home safe at the end of the day". Shortcuts get people killed.

Hoopie,

[WA1GFZ]

Tom,
50 pounds ago when I used to rock climb my brother would make sure nobody would step on the rope. This stresses the fibers
and creates a weak point. I used dual ropes when I raised my log in case one broke. Redundant systems can be a pain with a pully system though.
6 trips, your feet must hurt today.

An old buzzard told me a story once how his friend almost destroyed his log as a kid.  He washed it with gas after a date.

[W1UK]

Glad you dodged the bullet OM!

I have some friends who are serious rock climbers.  They replace their ropes on a regular basis whether they look fine or not, and they are using top quality kernmantle stuff.

Another thing to consider is working load versus breaking strength.  Safe working loads are usually 10% of the breaking strength of the rope when it was brand new and unused.  

[Glenn NY4NC]

As Gomer Pyle might say... "golly Sgt Vu"!!!! Very glad to hear you are ok-fine after metal vs earth death match. 

400 pounds is way too heavy for one antenna dude!... How much will the 20m yagi weigh?

PS... I love your new avatar.... makes me feel like a handsome guy!

[Bacon, WA3WDR]

Tom - it's a wonder any of us survived childhood, much less living to such an age.  I'm glad nobody got hurt.

[K1JJ]

Thanks for the comments, guys!

Yes, Al, 10% is the limit for a safe load. And for NEW rope.

I climbed up there today to clean up and found the other mangled piece of frayed/cut rope. Evidently it broke in mid span, then whipped up to the tower top as the log fell, then tangled in the tower and broke again...  I also found some plexiglass insulator pieces from the log on the ground where the rope tangled and snapped the second time - must have shook the log pretty good...

In the past I usually used overkill for ropes, but since nothing's happened in 20 years, I guess I got lax and used this lighter 1200 pound test stuff for a job that really required my 2,000 pound better quality nylon. Live and learn.  Gonna use the 2,000 from now on.

I'll  take some pictures this afternoon. While I was up at 100' today I could see a great view of the mangled elements on the ground, so will do.

BTW, when it slid down the tram line, I was about 200' away on the tractor, letting the rope play out slowly, so I was not at risk when it fell. The risk was when I was up on the tower doing the rigging when at one point this rope held most of the weight.  I think the shuddering of the log as it started down the tramline is what stressed the control rope and put it over the edge. Maybe at times like that the load increases several times. Just like jerking your own Johnson on a rope.

T

[W1RKW]

T,
How are the pulleys?  Do they rotate freely under load?

If you ever need a spotter let me know.

[K1JJ]

T,
How are the pulleys?  Do they rotate freely under load?
If you ever need a spotter let me know.

Hi Bob,

Thanks for the offer. 

Yes, the pulleys rotate FB under load, They are 3 ton rated monsters, so no problem. I also use that nylon seat belt type material for the rigging to the boom, so that's good for 2 tons at least.

It's a pity I spent the whole day being anal about everything and then  screwed myself with a rope that was weather beaten..

Glenn, you axed about the plans for the 20M Yagis. I plan to use the same log booms at 60' long and maybe lengthen them to 75'. Will make WIDE spaced  4 or 5el Yagis and stack a pair at 60' and 120'.

The 10M beams will probably be more like 50' booms and stacked  lower on another tower for optimum vertical pattern according to the modeling. 

I find I need to focus on specific bands and make a big effort or I get bored real fast. With the log I rarely got on 10-20M, but when I had a 2el X 2el X 2el 10M stack I used it every time I heard an opening. Fun to me is in high performance stuff, I guess.

BTW, I took some pictures of the damage - will post them when  I get in after dark.

T