Tuesday, August 16, 2016

The Best Tower Climb

I first became aware of amateur radio before I was a teenager, before I had any understanding of the technology and science of wireless communication. To me an antenna was rabbit ears on the family television. Gradually I became aware of loop antennas inside AM (MF) radios and telescoping rods on FM broadcast receivers car radios. Height only entered my awareness when my parents opted for a rooftop antenna so that we could watch US television from stations in northern North Dakota and Minnesota.

Fatal attraction? (Wikimedia Commons)
I was aware there were big towers some distance outside the city. I did not immediately connect them to coverage area and performance of television and radio broadcasts.

As my knowledge of amateur radio increased I began to notice backyard towers, usually small ones, supporting curious contraptions that I soon learned were called yagis. Apparently these were superior to bits of wire in the same manner of the television antenna (yagi or LPDA). But to me the towers were simply convenient supports; my awareness of height as a performance factor came later, after I got my ticket and absorbed the knowledge of more experienced hams.

It didn't take a genius to realize that towers are dangerous. An older high school friend suggested I try to climb his small tower to see what it was like. I did it ladder-style, with bare hands and no safety equipment. I still remember the fright I felt when I reached 20', about roof level, and looked down at him. That's as far as I got; I quickly retreated to the safety of the patio. He laughed and explained how it was the same for him until he got over the natural fear of climbing. Soon enough I had my own tower, on which I learned to climb safely and without undue fear.

Why do we have towers?

There are good reasons and bad ones for having towers, especially big towers. After all, we would never need to climb towers if we didn't benefit from them.
  • Performance: Height improves performance by lowering elevation angles for our horizontal yagis. At least up to a point. Tall towers also permit stacking and room for multiple, side-mounted antennas. How much performance you insist on will depend on your budget and objectives. More towers may be more suitable than a single tall tower.
  • Support: Antennas need to be supported at some height. Trees and buildings may be unavailable or difficult to use. Towers can be engineered to support the antenna load and place them above obstructions, decouple from the environment and turn freely.
Apart from sensible or at least justifiable objectives there are others. Like big boats, big houses and big cars a big tower is often an ego booster. It can also be a giant phallic symbol that is attractive to a certain mindset. Although there is nothing necessarily wrong with putting up a big tower for these reasons (it's your money and your risk) we ought to honestly reflect on our true motivations. All I would ask these hams is whether they want to risk their lives climbing a status symbol?

Benefit vs. risk

We each have our perspectives on measuring benefits and risks of towers. Some are based on science (mutual coupling and far-field pattern production) and others on local circumstances (regulations, insurance, personal health, budget). The decision to put up a tower and what type of tower and antennas will not be the same for everyone. Apart from the science what we do have in common is human physiology and gravity: if you fall you will die or be severely injured.
From: Simplified Safety blog article

Safety equipment is no panacea. All types of fall arrest systems encumber our movements, are easy to use incorrectly, can be costly and require careful maintenance. When they do come into play you will still be injured. The most common fall arrest systems are the tower-attached cable with cable grab and hand-placed fall-arrest lanyards. Both require a full body harness that is properly adjusted and used.

When you fall the equipment will stop your fall, but not without slamming you against the tower after a short drop. The rapid deceleration will further injure you, even with the proper equipment. The more you weigh the worse the potential injury. You may be unable to reattach to the tower or descend without assistance and you may suffer injury from blood flow interruption from being suspended by the harness until rescue arrives.
CDC report

The higher the tower the greater the chance of falling. Climbing, descending and working at heights are acts of heavy physical labour. The higher the tower the more likely you are to become exhausted or feel the effects of the weather (cold, sun, etc.), and the less likely you can be reached in an emergency. If you are overweight, in poor physical condition and not sensible about reading and interpretting the messages your body is communicating to your brain the risk is multiplied.

These are serious risks. Are you prepared? Are you willing to learn and do it right? When you're young it is often possible to use agility and main strength to recover from stupidity. Most hams nowadays are not young. In any case relying on luck and youth is a poor strategy.

How do you calculate benefit and risk? That's for you to decide, for your own life. Be honest with yourself. It may be that a tower is a poor choice if you (or your family) judge the risk of climbing to be too great. There is nothing wrong with coming to that decision.

Perhaps just as important, consider whether you are covered in case the tower falls or a child comes to grief on your property. Taking preventive steps for your "attractive nuisance" can be as valuable as buying insurance.

Alternatives to climbing

The benefit vs. risk assessment can be improved by alternatives to you, the tower owner as tower climber. Many older hams do just that. There are several approaches available:
  • Tilt-over or crank-up tower
  • Outsource to a friend or a professional climber
  • Man buckets: crane lift or bucket truck
All of these options are costly, though less costly than human life, and even then involve danger. Since many older hams have more money than fitness the expense is justifiable. You may not even have to limit your height ambitions since there are man buckets for cranes that will take you up 40 meters or more.

One thing to beware of with bringing in a climber, whether amateur or professional, is liability and insurance. Most hams don't worry about this too much since disasters are rare. Yet a disaster in one sense can become one in another sense. Your buddy may accept the risk of injury but if he should die working on your tower it is his family that may initiate action. Even when dealing with a professional be certain that he has suitable accreditation and is bonded and insured.

You don't have to do this if you are unwilling to accept the risk. However, avoiding the issue is not the same as consciously and conscientiously accepting risk.

The best tower climb

I have a curious confession to make. So far in 2016 I have not climbed my larger tower even once. I have been up the smaller, house bracketed tower a few times but that was only to access the roof for non-ham related tasks. I have climbed towers this year but only those of other hams.

The reason is simple: nothing of note has gone wrong on the tower and the antennas it supports and I have not added or removed any antennas this year. This brings us back to the subject of this article, the question of what is the best tower climb.
The best tower climb is the one you don't have to do.
Every time your feet leave the ground you are in mortal danger. The only way to truly avoid that danger is to avoid climbing. Of course since we want towers to gain the benefits they give us we cannot avoid all climbing, or any of the alternatives to climbing discussed above. What we can do is reduce our climbs to the minimum number possible. That is, to remove the necessity of climbing.

When is a climb necessary?

To understand how to avoid climbing we need to review the reasons for climbing. From this you'll immediately see how we ought to attack the problem.
  • Tower raising and removal: This may seem trivially obvious but it is not so simple. When I raised my towers on my own I did so knowing that I'd have to climb up and down more than if I had a crew. With a good crew you can raise a tower in pretty much one climb, going up section by section and descending when you're done.
  • Antennas: When done right you put the antenna up and it stays there, perhaps for many years, until you choose to replace or remove it. Do it wrong and the antenna, and you, will make several trips up and down. The lesson is to build them right, use good material and fasteners, and tune them before they go up to the top.
  • Connectors: Use the best connectors on all cables (coax, rotator, control lines, etc.), install them well and follow best practices for weatherproofing. By avoiding water infiltration, fatigue breaks, corrosion and intermittent or failed connections you will not have to climb the tower diagnose and repair or replace what could have been done properly the first time.
  • Quality: Buy and install the best equipment you can afford for your tower installation, and refurbish, repair or inspect everything before it is raised. This goes for rotators, supports, coax, baluns, and everything else. That special deal you got at the flea market will seem less special on the fifth trip up the tower to make repairs.
Practice safety

When you do have to climb plan it out so that there is little chance of requiring more than one trip up the tower, such as having all the tools and parts you need. Binoculars or a drone flight are your friends. They allow you to do a visual inspection of suspected problems before you get started, potentially saving one or more climbs. From the shack use an analyzer and ohmeter to identify connections that may have failed or impedances that are no longer what you recorded when antennas were first installed.

The greatest danger of tower climbing is ascent and descent, not the act of working at height. Even so there is danger from remaining on the tower for a long time. Every aspect of tower work involves risk. There are ways to reduce the risk for both climbers and crew. Make safety a routine in every tower job you do.
  • Inspect all equipment: Before every climb inspect your safety equipment, ropes, fasteners, hard hats and also the tower itself. Don't become lazy about it. Hams are often surprised by the routine I follow and some find it foolish. Ignore them; do it right.
  • Know your limits: Are you fit? Are you feeling 100%? Is the weather uncomfortable? I can honestly say that I am fitter than well over 95% of all hams and I have my limits. Tower work is fatiguing and it becomes worse as the tower height increases: longer ascents and descents and longer hauls on ropes. Don't ever become overconfident. When that happens you will make mistakes.
  • Descend before you have to or call a break to rest. When the chill begins to restrict circulation, the harness causes muscle soreness or you experience tremors from standing in one spot for too long it is probably time to return to the ground. If you wait until you can no longer continue to work it is too late. You may not be able to safely descend. The taller the tower the greater the danger. Consider taking up a small snack (energy bar) and water bottle for long jobs and warm days rather than descend to eat.
  • Avoid fools and mavericks: Every member of your crew, including yourself, ought to be mature adults who appreciate the danger of tower work, do not take unnecessary risks and will not do something unexpected or inappropriate. They risk not only themselves but everyone on the team. Weed them out early. If you can't easily prevent their inclusion find suitable tasks for them that are helpful while keeping them out of the way of others.
"Experience is a dear teacher, and a fool will learn by no other"

Most of what I know about tower work I learned from more experienced hams, the safety literature and a number of professionals I've had the opportunity to work with over the years. Listen, watch and learn. There are too many hams that ignore all good advice and seem surprised when things go wrong or their tower crashes to the ground. While my own safety practices are not always perfect I always strive to apply good sense as I go about a job.

Unfortunately when I do tower work for others there are those who will not listen to advice on equipment choice or proper installation technique. For them faith in myths overrides science and evidence. This is disturbingly common among hams. Sometimes I can ignore them simply because they don't climb and can't see when I've done a job right rather per their instruction. In this way I avoid future climbs.

Yet common civility can only go so far. There comes a point when I just won't do a job, whether because of the equipment used, their insistence on unsafe practices or the quality of people they bring in to help. It can be a difficult choice.

Stay safe, do it right, and if you can't make others cooperate be prepared to walk. You may lose a friend but avoid mortal danger. That's another way to have the best tower climb: none at all.

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