With regards to the Seattle tower crane collapse, I feel obligated to warn, once again, about shortcuts and “well, it worked last time” procedures that are frequently used (worldwide) during tower crane assembly, disassembly, and climbing operations.
I have personally (as an operator) been subjected to shortcuts countless times. In fact, I reached my limit in 2008 I was asked to "climb-down" a Peiner 415 Tower Crane for disassembly that was over 460 ft high. The morning I started my ascent, I noticed that all of the mast bolts were loosened—many not even to finger-tight! Before making it to the cab, I decided to climb down, and left the jobsite—lets just say, this did not go over very well with the dismantle crew.
In 2012 a Peiner Tower Crane in Dallas, Texas, collapsed during disassembly due to not only loosened bolts, but also removing them as well, resulting in the deaths of two ironworkers. This compelled me to go public, speaking out in an article in ENR on July 23, 2012, warning that loosening and/or removal of bolts or pins “prematurely” is for some companies, a common practice.
It is obvious that all the pins to every other mast section (including the cab / slew-ring) were removed from the Seattle tower crane. This made the vertical mast vulnerable to a wind pressure that would have never toppled any tower crane if the pins remained in place. Maybe this time, my whistle-blowing will be recognized by the tower crane industry as valid, instead of dismissed.
Terry McGettigan is a tower crane specialist and operator. He has over 40 years of experience in the industry, running his first tower crane in 1978. Formerly certified as a crane inspector by both Washington State's L&I and California's Cal/OSHA, he is also a factory-trained tower crane technician with all the leading manufacturers. He has documented past crane accidents on his website www.towercranesupport.com which can be viewed here. He is currently based in Seattle, Wash.