As engineering budgets get stretched thinner and thinner, there seems to be a tendency to concentrate efforts at the studio at the expense of the transmitter facility. Neglecting the transmitter site, and tower in general can have catastrophic effects. Many large market stations are privileged to have multiple sites, but in the small- to medium-sized markets, the failure of vertical real estate results in not only a large reconstruction budget, but also the potential long term hemorrhaging of money.

Photo by Frederick Noronha. Used under a Creative Commons license.

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First and foremost in any tower maintenance program is to build a solid relationship with a tower crew; and you get what you pay for. The crew that performs the work for bargain basement prices may tend to have greater personnel turnover, and lower experience and quality levels. This tends to limit continuity between visits, and reduces the opportunity for your crew to observe trends in a particular structure over time. If unsure about the skill or reputation of a crew, seek out your colleagues in the market or region.

Set a plan

Once your crew is lined up, it is a very good idea to meet with the supervisor and discuss your maintenance program. Meeting face-to-face enhances the comfort zone and puts all parties on the same page. Face-to-face communications also sometimes jog memories too, so an opportunity to share historical information about a site is gained. The passing of this knowledge may wind up being crucial down the road to preventing a failure.

In general, consultation with a structural engineer is probably unnecessary for routine tower maintenance. Obviously if items outside of the design criteria are to be added to the structure, a review by an engineer is necessary. Similarly, if a routine inspection uncovers out of the ordinary items such as broken bolts, foundation failure, etc., a reputable structural engineer should be called in as soon as possible to review the findings and recommend a necessary course of action.

Two other persons should form your tower maintenance team: The first is a competent antenna engineer. This person does not necessarily need to be in close proximity to you, but he or she should be readily available for consultation and fieldwork if necessary. The final member of the team is of course the station engineer, who has the most frequent and regular contact with the structure. The engineer should be making cursory examinations, but these are never a substitute for a full-blown inspection.

The frequency of a more in-depth inspection can vary depending on the nature of the site. A naked tower that is a member of an AM directional array in the middle of a cornfield may not need to be fully inspected as often as an older, fully loaded tower in a densely populated area. Regardless of what schedule you utilize to maintain and inspect the tower, it is usually a good practice to have the tower climbed at least once per year. However, exposure to earthquakes and severe storms, etc., might affect the integrity of the structure and will necessitate a greater climbing frequency.

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