This is not true. There was a crew change on this crane but it took place several weeks before the accident. The original crew Flagman and the project manager for Mitsubishi Heavy Industries had butted heads from day one. I'm not sure what it was all about but do know some of it was site conditions, compaction and how level it was. Mitsubishi wanted him fired and they finally won out and Lampson swapped crews with another Transi lift they had running somewhere else. There was concern expressed the morning of the accident about the wind by both the Crane Crew and the Iron Workers but Mitsubishi's project manager decided to go forward with the lift.
There was finger pointing in all directions after this happened but Lampsons Crew was cleared of any wrong doing. Lampson was fined by OSHA for a few infractions.
You are right about the crane crew change out being a couple of weeks before the accident, apparently the original operator/crane crew/ironworkers had a number of run-ins with the Mitsubishi PM (Grotlisch) over ground conditions, rigging, wind, about everything you can imagine to try and keep the project on schedule (famous last words.)
As for the cause, it was determined to be wind loading
the Transi Lift was cleared of any structural problems by Exponent Failure Analysis Associates, 149 Commonwealth Drive, P.O. Box 3015, Menlo Park, CA 94025, USA
There paper describes the comprehensive engineering analyses undertaken to disprove the Mitsubishi theories of failure as confirmed by jury verdict. Among the topics discussed are: wind tunnel testing, structural analyses of the boom, metallurgy of failed parts from a critical king-pin assembly, and soils engineering work related to ground loads and displacements during the lift. Crucial role of the SAE J1093, 2% design side load criterion and Lampson’s justification for an 85% crawler crane stability criterion are presented.
Excerpts from the Milwaukee Journal Sentinel during the trial.
"Site Superintendant Grotlisch (Mitsubishi) admitted under examination that he had "dropped the ball" the day of the accident and that he had no idea what effect the wind would have on the roof piece being lifted.
That was because nobody at the job site did so-called wind-load calculations, which are commonly (should read always done) done for crane lifts in windy conditions. They are designed to predict the effect of the wind on the load being raised.
Employees of Mitsubishi and Lampson each testified that they thought the other firm was doing the wind-loading calculations. Lampson employees maintained that they explained to Mitsubishi officials that Mitsubishi would be responsible for doing them."
Come on guys, a 100 × 180 × 16 ft open truss panel roof section weighing close to 500 tons at a lift height of 230 ft."and nobody bothered to ask about the effect of wind on the load, I find that a little hard to believe.
"Testimony showed that Grotlisch went to the Mitsubishi construction trailer shortly after the accident and that someone unplugged the firm's weather computer there, leaving no record of the wind speeds measured at the time of the accident."
ya think that someone had an idea they were dancing on thin ice?
According to Steve Prior, of WeatherData a private weather service in Wichita, Kan., sustained winds at the time of the accident were 23 mph gusting to 28 or 29 mph.
I have ran several cranes with an anemometer mounted in the boom, they are a man made instrument and prone to inconsistencies, I always look around for things (wind socks, flags, trees,ect) to reinforce the mechanical readings just to be sure.
I'll give you James Headly's remarks on that (owner of Crane Institute of America, one of the most respected crane safety companies in the US)"I can't believe they would want to do it. I can't understand it."
It goes on and on untill the
COURTS decide that Mitsubishi is 97 % responcible and Lampson is 3%, which brings me to the crux of this post.
In my opinion one simple word could have saved 3 lives. That word,
no should have to come from the operator had he had any reservations about the lift (like meabe the other crane ops on-site had been suspended earler in the day due to the wind (Milwaukee Journal Sentinel) )! Like it or not he made a conscious desicion to pull the lever and lift the load. Whether he was bullyed or threatened or what ever by a PM or Super, it is irrelevant, as the operator he has the last word in any lift!
The point I am trying to make to any crane operator regardless of experience is that you are the LAST word for any lift, when you sky the load you have checked and rechecked every aspect of the load, from the ground to the crown and all inbetween, use that power.
my apologies for the long post, I hope I have not PO'd anyone, but felt that since this was probably one of the most catastrophic crane accidents we have ever had some things needed to be cleared up. I apologize for my inaccuracies in the orignal post.
Joe