A 220 tonne five axle All Terrain crane overturned in Irving, Texas, on Sunday when the ground gave way beneath an outrigger jack.
The crane a Grove GMK 5275 (GMK 5220) from the Davis Crane Services fleet was set up in a residential street, apparently to lift an electrical transformer. it appears that the crew had set some substantial mats up on the load side of the crane and fully extended the outriggers, But did not take similar measures to the rear, where the outriggers were short rigged and set up on the pavement/sidewalk with relatively small mats.
The operator had partially extended the boom and elevated it, this had the effect of placing the full weight of the counterweight on the rear outriggers, one of which punched through the pavement surface as the counterweight was slewed over the top, causing the crane to overturn rearwards. Fortunately it came to rest on its counterweight, so damage was minor, apart from to the pavement, and no one was injured.
A larger crane was called in to recover the stricken crane.