My main hoist brake gave out halfway through a lift yesterday

I was setting a 12-ton HVAC unit on a roof in Cincinnati, about 30 feet up, when the load just started to drift. No warning, no weird sound, it just wouldn't hold. My heart jumped into my throat. I immediately hit the emergency stop and radioed my ground crew to clear the area. We had to slowly lower it using the auxiliary hoist, which felt like it took forever. The whole time I'm thinking about what if that had been over people or a street. Turns out the brake lining was just completely worn through. I check my logs, but this one slipped by. Has anyone else had a brake fail like that with zero noise first? What's your check routine for them?

4 comments

4 Comments

the_hayden1mo ago

That feeling when the load starts to drift is the absolute worst. I had a similar scare with a shop crane years back, though thankfully it was just a toolbox and not 12 tons over Cincinnati. My check routine got a lot more paranoid after that, basically a visual and a light tug test before anything leaves the ground. It's spooky how they can just go quiet like that.

daniel_carter1mo ago

Yeah, ray215 has a point. Full load test is the only real check.

evan_grant704d ago

Ever see a brake pass a tug test but still slip under real weight? I watched a rigger test a hoist that way and it held until the load actually swung. That quiet failure is exactly why you need the full test.

ray2151mo ago

Glad you're okay, that's a nightmare scenario. Quick question though, you mentioned doing a light tug test? For a main hoist brake, shouldn't you be doing a full rated load test on the brake during inspections, not just a tug? A visual and a tug might not catch a lining that's hanging on by a thread. Our routine is to test it under the actual load it needs to hold, every single time, because a quiet failure is exactly what you're trying to find.