Another flying issue

Mark Dawson

Freshman
Jul 3, 2011
61
0
6
I wasn't sure if this should be in the basement. But here is a pic that another company posted on their facebook page. Shows their home-brew flying system. And no they arent certified welds....

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Re: Another flying issue

YIKES! I tried to find something "right" about this, and haven't.

The climbing carabiners all have laod ratings and appear to be the locking type. Unfortunately, if they are locking, most of them are upside down...

But no, that contraption has no business lifting anything over people. If the owner of the equipment doesn't care about the gear and the drop zone is appropriately access restricted, it probably won't cause any injuries. But that'll be because nobody is within range.
 
Re: Another flying issue

The climbing carabiners all have laod ratings and appear to be the locking type. Unfortunately, if they are locking, most of them are upside down...

But no, that contraption has no business lifting anything over people. If the owner of the equipment doesn't care about the gear and the drop zone is appropriately access restricted, it probably won't cause any injuries. But that'll be because nobody is within range.

Not sure what 'biners cost these days, but 3' SATC (deck chain) would probably be cheaper.

I suppose asking to see the stamped engineering drawings would be too much...
 
Re: Another flying issue

Isn't that a Harbor Freight electric winch?
To me the only thing missing is the baling wire and the structural duck tape.
 
Re: Another flying issue

So for those of us that dont know what we are looking at...what is wrong.
The list of what's right is shorter: they don't appear to have modified the manufacturer's rigging of the boxes. Other than that - a non-exhaustive list would include:

- Non-rated truss
- "Custom" motor platform/mount
- Using a winch as a lifting device - no failsafe braking, what looks like 1/8" cable instead of graded chain, no traceable maintenance schedule, etc.
- not using lifting shackles, spansets, eyes, etc.

I'm curious what's below this picture - did they use dog chain to guy the "tower" to someone's car parked nearby?
 
Re: Another flying issue

The list of what's right is shorter: they don't appear to have modified the manufacturer's rigging of the boxes. Other than that - a non-exhaustive list would include:

- Non-rated truss
- "Custom" motor platform/mount
- Using a winch as a lifting device - no failsafe braking, what looks like 1/8" cable instead of graded chain, no traceable maintenance schedule, etc.
- not using lifting shackles, spansets, eyes, etc.

I'm curious what's below this picture - did they use dog chain to guy the "tower" to someone's car parked nearby?

I too would like to see a few more pictures from different angles.

To me the winch doesn't matter in this instance, as it isn't holding the load at all (the load is dead-hung on those 'biners.) It appears that they've put quite a bit of good thought into the overall design. I don't see what might be mod'ed in the box's rigging, but I'm not familiar enough with that manufacturer's techniques to know.

There must be much more to this, as I also don't see what is keeping the truss from falling over.
 
Re: Another flying issue

The list of what's right is shorter: they don't appear to have modified the manufacturer's rigging of the boxes. Other than that - a non-exhaustive list would include:

- Non-rated truss
- "Custom" motor platform/mount
- Using a winch as a lifting device - no failsafe braking, what looks like 1/8" cable instead of graded chain, no traceable maintenance schedule, etc.
- not using lifting shackles, spansets, eyes, etc.

I'm curious what's below this picture - did they use dog chain to guy the "tower" to someone's car parked nearby?

Yep... truss rather than tower. I'd have to see if the truss is rated and certified for vertical use.
The winch mount doesn't *appear* to have any stays on the back side. The whole point of rigging is to transfer the load straight down, centered over the tower footprint. This thing appears to have no way of accomplishing that.

The winch DOES bother me, even if it doesn't hold the load. It's very likely not rated for overhead lifting and I'm pretty certain it's not rated for lifting over humans. Most rigging failures occur during movement, so the fact that they used 'biners to hold the load is a small comfort, as failure is more likely to occur when lifting.

Also curious about what isn't seen here. The cheeseborough clamp and horizontal pipe visible just behind the 3rd PA box makes me wonder if the tower is connected to the canopy frame to the left. I don't see anything that keeps the tower from falling forward.

Also missing are any obvious guy lines on the tower, outdoors and subject to wind.

Any time I see home-brew stuff like this it makes me wonder about safety. There are multiple reasons our industry has adopted certain ways of doing things, primarily revolving around not injuring or killing people. Profession engineering design, destructive testing of prototypes, traceable materials & fabrication certifications, and standardized rigging practices all came about because it's better and cheaper to do it right than get sued when the "PA farmer" (thanks, Dave Stevens, for that phrase) contraptions fail.
 
Re: Another flying issue

An update. This was done in our area. The pics are courtesy of the company's facebook. I know who made this, and despite welding better than me, a structural welder that does not make. The carabinas may be rated, but there are better options. The motor is a cheapie, and carries the load fully whenever raising or lowering. The flying frame is the real one for the speakers, but atop the tower is simply a design knocked up by the shop boy. The speakers weigh 251 pounds plus the flying frame. At 9.8m/s/s that's going to make a sizeable dent. Here are some more pics of it...12039_562996767048359_837278319_n.jpg222212_562996597048376_585534991_n.jpg430930_563049007043135_1350129974_n.jpg578023_563049117043124_43365351_n.jpg
 
Re: Another flying issue

Thank you for the additional photos. Quite honestly, I see very little wrong with that system. They have the truss loaded in its strongest direction, they aren't relying on the motors to hold the load, they've definitely overbuilt that "knocked-up design". I'd like to see something better than a truck strap as the 'counter-weight' on the back, since it is holding at least a 400# load. I'd also like to see how they are keeping it upright, but I'm guessing the subs are ballast. A nice touch is the subs being strapped down so that they don't suddenly stop being ballast.

I've posted some scary rigging pics here before. This doesn't come close, and I would have little problem being under and/or around these. I'd bitch about the truck straps and tell them they need to replace those 'biners with proper wire rope slings, but that's about it.

(Quite frankly, the most dangerous part of these assemblies is the requirement that someone get to the top of that tower to do the dead-off.)
 
Re: Another flying issue

It is obviously hard to tell with certainty, but given the load and making some assumptions about the base frame, that looks like a fairly stable setup not at all challenged by the load it is carrying. Assuming that the lift motor is somewhat lacking in terms of failsafe braking, the only thing I would be sceptical about is the carabins, to me they look like aluminium stuff of fairly low rating, but I might be wrong on that account. The trusses look like steel trusses, the load looks to be balanced. I wouldn't bee too worried.
 
Re: Another flying issue

It is obviously hard to tell with certainty, but given the load and making some assumptions about the base frame, that looks like a fairly stable setup not at all challenged by the load it is carrying. Assuming that the lift motor is somewhat lacking in terms of failsafe braking, the only thing I would be sceptical about is the carabins, to me they look like aluminium stuff of fairly low rating, but I might be wrong on that account. The trusses look like steel trusses, the load looks to be balanced. I wouldn't bee too worried.

The use of an unrated, uncertified ratchet strap as the "stay" on the upstage side of the tower is dangerous. In competent jurisdictions this would not pass any "temporary entertainment structure" inspection. This might 'fly' (no pun intended) in Norway, but it would never make it in Germany or the UK. Sadly, in the USA shit like this goes on way too frequently.
 
Re: Another flying issue

The use of an unrated, uncertified ratchet strap as the "stay" on the upstage side of the tower is dangerous. In competent jurisdictions this would not pass any "temporary entertainment structure" inspection. This might 'fly' (no pun intended) in Norway, but it would never make it in Germany or the UK. Sadly, in the USA shit like this goes on way too frequently.

Many ratchet straps are rated but not certified. The one used here may fall in that category. Doesn't make it right, though.