Ed,
I first learned of this tragedy from a friend this morning, and have been
catching up on the news reports. This report indicates there was a shackle
failure:
http://wirelessestimator.com/articles/2018/fund-set-up-for-mastec-constructi
on-manager-who-died-in-weekend-tower-collapse/
I like to put an EHS safety wire across any shackle, just as we put them
through the turnbuckles, as a bit of insurance should there be a component
failure.
Your temporary rope guys are a good idea. Mandatory of course for a pier-pin
base (we don't know what base this had). I generally use EHS steel for
temporary guys, using Klein Chicago grips to hold the lower ends.
One of my clients opted for the much larger self-supporting base on a recent
guyed Rohn 55 installation. Four feet or so of the first section was set in
the base. This larger than normal concrete base was of course more
expensive, but this provided for an extra level of comfort and safety before
the first set of guys were attached.
The Rohn book says 70 feet of Rohn 25 should be guyed at 32 and 65 feet, for
the lower two wind speed ratings, or 32 and 68 feet for the 130 mph rating.
It appears the Tennessee one varied from that, though if the shackle was
flawed the guy spacing likely wasn't an issue:
http://www.rohnnet.com/files/2015_Rohn_Full_Catalog.pdf#page=26
Unanswered questions remain about the size and quality of the shackles used
in the Tennessee tower. And were the guys tensioned correctly or
overtightened?
73/Jon
Jon P. Zaimes, AA1K
Tower climber for hire
http://www.aa1k.us/
Cell: 302-632-2353
Reviews of AA1K tower work on eham website:
http://www.eham.net/reviews/detail/12922
Hug your favorite tower every day, and always stay connected to it.
-----Original Message-----
From: TowerTalk <towertalk-bounces@contesting.com> On Behalf Of Edward
Sawyer
Sent: Friday, October 12, 2018 1:26 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Learning from Tragedies
I am sure that many of you have heard about a recent tower climbing death
installing 70ft of Rohn 25G. The details of the story made me think about
my tower building processes and I am wondering how they compare with others.
I personally have 70 ft of Rohn 45G and it is guyed at 35 and 70 ft. I am
not sure I would be comfortable with 70 ft of 25G guyed only at 35 and 70
ft. What are the thoughts of the group here?
When I build towers, even with a fixed based set in concrete, I rope guy
each section after 20 ft. So when I am putting the 30 ft section on, my
standing tower is rope guyed at 20 ft. As I would be putting the first set
of guys at 35 ft (if it were 45G), I would be looking at rope guys coming
down from 20 ft and 30 ft levels and then would have the 35 ft guys
available to me as I am clipped in at the 30 ft level after gin poling up
the section with the 35 ft guys.
Secure the permanent set of guys and then drop all the ropes. My next
section 40 - 50 ft would have rope guys I can access at 40 ft and those
would be secured at the 50 ft level before moving the gin pole up to 50 ft
and so on.
It does not appear that the above method was used in this tragedy from the
descriptions. Obviously, if there was a catastrophic guy anchor failure,
the above would not prevent that. There is no mention of the guy anchors
used. Hopefully if it's a 2 guys system, earth anchors were not the choice.
In the interest of honoring the event, I though a discussion of the tower
stacking techniques of the community might be in order.
Ed N1UR
A young Tennessee father of five is dead after the Amateur Radio tower on
which he was working collapsed due to a guy anchor letting go.
Thirty-year-old Ken Waddell was killed on September 29 while attempting to
erect a 70-foot Rohn 25G tower on the property of Dale Darling, W9WBA, in
Cookeville, Tennessee. A professional tower climber, Waddell handled the
tower job on a freelance basis, rather than for his employer.
According to media accounts, Waddell and Darling checked the new guy anchors
in advance of putting up the tower. Waddell was getting ready to attach a
second set of guys at 70 feet when a guy at the 40-foot level let go, taking
him to the ground on the section where he was attached. He was the only
person on the tower when it fell, and died at the scene
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