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Crane tips in Alberta

We finally have the information on the crane that went over in late April at a CNRL (Canadian Natural Resources Ltd) facility in Alberta. We understand that it is the Horizon oil Sands Project in Fort McMurray.

The crane, a seven axle Liebherr LTM1400-7.1 owned by Mammoet, was apparently being driven into position to work on a flare stack- fully rigged with luffing jib, boom retracted and raised to full elevation.
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An overview of the site

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The crane tipped over on its side

The cranes outriggers were partially extended – at least on one side – as a precaution. The only thing for certain after that is that the ground was not sufficiently flat or firm and the crane went over sideways. Thankfully no one was injured.

Why it happened we may never know, as is typical in these situation different people on site have different versions of what happened. In this case discussion appears to revolve around the crane deviating around an obstacle onto less firm ground than was planned and a disagreement between the operator and a site supervisor etc… etc…
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The crane had a jib installed

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The underside of the crane

Vertikal Comment

What really happened here we may never know, CNRL appears to have a poor safety reputation among many of those on site, but then they may have an axe to grind? The fact is that there are lessons to be learnt from incidents such as this that might save lives in the future.

Mammoet has a good safety ethic and has in the past been more than willing to share such information with the industry as a whole, hopefully it will be able to do the same with this case, once the investigation is complete?

Moving big All Terrain cranes with the boom up is a risky business that is best avoided if possible. When essential it is one of those jobs that need to be ‘over planned’ – Looking at the ground in the photos we have been sent, suggests that ground preparation was… well… not over done…and the distance the crane had to travel looks to be substantial?

We will update this article when and if we receive further information


FAO Mr Mike Duhamel of Mammoet Inc of Canada.

Good Morning Mr Duhamel,

Please publish the Conclusions of your Official Report which enquired into the Root Cause(s) of this Crane Overturn incident in Alberta, Canada during April 2011 ?

The objective being that we can all learn from this potentially fatal incident and thus introduce additional Control Measures to ensure no repetition of these circumstances.

All requested in line with the consensus reached by Attendees at the Crane Safety Summit, held in Hamburg, Germany during March 2012.

Thank you and Kind Regards
Mike Ponsonby BA

Feb 23, 2013

FAO Mike Duhamel of Mammoet, Canada.

Good Morning Mr Duhamel,

Just for the record, all of the facts quoted in my two inputs below were calculations taken from the following sources.........

1. Liebherr Mfrs spec sheet for LTM1400-7.1 crane, dated November 2009 on the Rising Centre of Gravity as Crane was Rigged for lift, the Max Boom Angle with Luffer attached and the ULW of all Counterbalance Blocks fitted.

2. Boeing Aircraft Corp website, FAQ questions on- How to Calculate Imposed Loads on Tyres. Expressly the imposed load per square inch (Kg per square CM) on each of the Tyres fitted to this Full Rigged Mammoet Crane, that tipped over in Alberta, Canada in 2011.

3. HSE website in UK on 173 Fatal Injurys in 2011 and 171 killed at work in 2010. Of which on Friday 15th January 1988, one of those victims was David Stanford (d), killed by a Loaded Concrete Skip dropped by an NCK Crawler Crane.

Mammoet Board of Directors now know that Managing Safety is not a Cost, its actually a Cost Saving, ( As do BP for Oil Rig Fire). For Dangerous Occurrences like Overturning this Fully Rigged Mammoet Crane moved on a Dirt Road in Alberta, Canada, was entirely Foreseeable, Not Accidental and will have damaged this companies otherwise excellent reputation for Safety and Good Quality Workmanship.

Safety is Everyone's Responsibility, not just yours and mine. So may I suggest that we start Actively Managing Safety, not just producing Lift and Rigging PLan's etc.

With Best Wishes to all my friends in Canada.

Kind Regards
Mike Ponsonby BA

Sep 18, 2012

FAO Mr Mike Duhamel of Mammoet, Canada.

Good Evening Mr Duhamel,

Thank you for your valued input, the content of which is noted.

As I have first hand experience of a Crane Induced Fatality and it effects on the Victims Widow, Two Sons and Three Daughters for the next 10 yrs, then it behoves me to personally speak-up for all those dead Men and Women, who have been killed by Cranes in the Workplace.

Mammoet is a large and Professional company, well known to me and for whom I have the greatest respect. Therefore as you are a Representative of Mammoet, then please allow me to set the record straight on this dangerous crane incident depicted above.

a) If this Incident occured in the UK, then in English Law, Mammoet as the Employer would be held to be 'Vicariously Liable' ( Liability without Fault) for the acts of all Employees, if it were proven that they were acting in the Course of his or her Employment.

b) So to move this Fully Rigged Crane of circa 492,800 pounds GVW (224 metric Tonnes) in a Boom-Up condition, with Luffing Jib fitted and all Counterbalance Blocks in place is dangerous at any time. But to move it on a Dirt Road is foolhardy, especially with such a High Centre of Gravity in the Boom ( Due to 82 degree elevation of Boom) and expressly so with such high vertically imposed loadings on each tyre of circa 320 pounds per square inch.

c) So when this Mammoet Crane fell over in Alberta, Canada on 26th May 2011, it could never ever be described as an 'Accident' for this incident was not Accidental at all, in fact it was entirely Foreseeable for anyone in Management who cared to look, that this Crane Could and Would Overturn.

Therefore in English Law your company are indeed ' Babysitters' ( your words, not mine) as your Common Law Duty is indeed to Train, Instruct and Supervise all Employees involved in the Safe Systems of Work required for Crane Ops. Moreover if your Crane fell over killing me, it would offer you no Defence whatsoever to say in Court that " But we are only the Planners ". For as the Employer your company is highly likely to be held liable for this occurrence and in the event of my fatality would is likely to attract Criminal Charges for Mammoet under Sections 2(1) and 3(1) of The HSW Act 1974.

Finally and in closing, your public support for the 'Culture of Blame' is reprehensible, as you should follow the agreed PR of the Crane Summit in Hamburg ( March 2012). Whereupon all Parties agreed that all Crane Incidents would be openly and transparently reported in the future, so that we could all learn lessons from each and every dangerous incident.

To summarise, all Hazards should be identified in advance, Risk Assessed for Possibility, Probability and Outcome. Then Control Measures put in place to Pro-actively Manage all Safety Risks, to be As Low as Reasonably Practicable ( ALARP). For it is only by Actively Managing Safety that we can all collectively drive-up Crane Safety Stds in the Construction Industry.

Please be assured I would welcome ( Welcome) the opportunity to ventilate these matters in an English Court of Law.

Yours Sincerely
Michael J. Ponsonby BA
Appointed Person, IRTE and IMechE.

Sep 12, 2012

Mammoet Canada and Worldwide has an excellent standard of quality, training, and expectations. Their risk and hazard assessments are thorough and complete. Planning of lifts and crane movements are discussed and documented. Responsibility to execute these plans lies in the hands of the operator. This route was planned and solid, crane configured to manufactures specs. A bad decision, not bad planning, caused this accident. The company and supervision are planners not babysitters. Outside speculation and inaccurate information is not valid.

Jun 3, 2011

Good Afternoon Friends,

Mammoet BV is a large and very professional European company well known to me, for whom I have the greatest respect. However on this occasion, someone Senior screwed-up big-style. Which is yet another example of Negligence in Lifting Operations that over the years has killed thousands of men on the ground, including my Father in Law David Stanford on Friday 15th January 1988.

Crane Incident Forensic Science is always an inexact discipline, because we can never quite replicate the precise ground conditions and wind speeds prevailing at the time that the crane overturned. However what we can say without fear of contradiction is that the Liebherr LTM.1400-7 is an excellent state of the art hydraulic telescopic crane and very safe when operated correctly. The Mfrs spec sheet gives us many clues as to what was the cause of this overturn situation in Canada, if not wholly then at least partly.

The Liebherr LTM 1400-7 weighs 84 tonnes in travel mode and has an overall height of 3.715 metres (or 12 ft 2 inches) to the top of the superstructure, so the Centre of Gravity (CoG) is approx 1.85 metres (6 foot) above ground level. But when rigged for lifting is then fitted with 100 to 140 tonnes of steel Counterweight Ballast Blocks, all of which are loaded one on top of another and mounted at the rear of the Crane Superstructure to a height of 5.2 metres ( Or 17 feet overall height) : This now means that the top half of the crane weighs approx 19% more than the lower half, with the CoG then raised to at least 2.6 metres ( or 8 foot 6 inches) above ground level. To then fit a two section luffing Fly Jib, to the end of the four stage telescopic boom is to increase the Centre of Gravity again. Moreover if the main boom is then raised to the maximum elevation of 82 degrees, what we have is a top heavy steel structure well over 15 metres high, weighing 184 tonnes plus Luffing Jib, with a Centre of Gravity way above the top of the Steel Counterweights.

So to move this Fully Rigged crane in a Boom-up condition is dangerous at any time, but to move it on a dirt road is foolhardy, for it only takes the smallest defection in tyre sidewalls or the ground underneath each of those fourteen tyres, carrying at least six tonnes per tyre (or 13200 Lbs each) for the movement to be multiplied many times, by the time it gets to the top of the boom. The Driver clearly recognised that his crane was unstable when he extended one outrigger, but that alone only added to the instability of this crane, for now we have a Crane with a very high Centre of Gravity, but with the weight divided unequally left and right of the cranes centreline (CL), all of which then added to the overall instability of this crane.

This incident could never be described as an 'Accident' for the intention to rig the Crane off-site, then travel forward to the lift site shows intent on the part of two or more persons. This means that it was known to be dangerous in advance, as confirmed by the crane actually overturning. So the facts speak for themselves ( Res ipsa loquitor) and were this incident to occur in the UK, would likely result in a prosecution for Mammoet under The Lifting Operations & Lifting Equipment Regulations 1998 : Moreover if a fatality were involved, could possibly lead to Manslaughter charges for all involved arising from a breach of sections 2(1) and 3(1) of The Health & Safety at Work Act 1974.

Mammoet BV may like to consider the following cost-effective suggestions for the future, as managing safety is not a cost, its a cost saving compared with Crane Recovery, Crane Repairs and Civil Suits by the Client for cash damages

1. Instruct all Crane Drivers and Riggers to read the Mfrs handbook, before operating the Crane.
2. Produce a Suitable and Sufficient Risk Assessment taking account all of the Hazards involved in that particular site, before the lift.
3. Appoint an Independent Person ( The Appointed Person) to produce a Lift Plan beforehand, taking account of all Safety and Statutory obligations.

To do otherwise is to run the risk of killing someone on the ground, with possible jail sentences for all those involved in the Chain of Causation including Managers and Directors ?

With Kindest Regards
Mike Ponsonby BA.

May 30, 2011
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