Slinging Specs

[3top]

Hi all,

folks I need some help!

Like always, my time spent on google is useless!

Can't find any references to inspection guidelines for external load - long line equipment.

Specifically I need limits for the use of steel cables, like in 2-pointers (2 cables with a hook on a single load-ring, etc.)

Somewhere, sometime I read for instance that a cable is to be considered obsolete when it takes a permanent set/deformation anywhere on its length - like a kink or sharp bend, anytime the cable is not straight anymore or the bend is smaller than a certain radius.

Of course there is more, like strand thickness, corrosion, etc.

I read it all somewhere, but can't find it anymore!!

There is lots of External Load manuals out there, that just mention general good condition on the gear.
But I am looking for specifc critera to validate or reject a sling cable, 2-pointer, 3-pointer, cable strap, etc...

I'd appreciate any lead to the source!

Thanx guys and gals!!

3top :cool:

[Troglodita]

3top,

The regulations vary dramatically depending on where you are operating.

In the UK for example CAP 426 gives very basic guidelines on Sling Loads but the Civil Aviation Authority (unless things have recently changed) lose interest at anything below the aircraft hook.

Normally the local regulations that govern crane operations will be much more informative than their Aviation equivalents if these in fact actually exist.

A large dose of common sense can often be the best tool when you have to make a decision. If it doesn't look safe - don't use it! Static test everything to at least 3 x times the maximum load that you are likely to carry. Don't use nylon slings. Check your flight manual to ensure pear & ring I.D.'s and bolt sizes are within hook limitations etc. etc.

If you are unsure don't go there!

Trog

[Pilot DAR]

Three references which may help:

FAA AC43.13 - 1B has a section on flight control cables for airplanes. If it's good in the plane, it should be fine under the helicopter, inspect it the same way.

Loos and Company are a very large manufacturer of steel cable of all kinds, including aviation. They offer all sorts of refernce material.

Crosby is a manufacturer of cables and slings. Though not specifically for aviation, they have an excellent safety guide, which I would think has a reference to inspections.

I hope that helps,

Pilot DAR

[spinwing]

Mmmmm ...


If you do a google search on .... "rigging" you will find lots of references ...

Fine tuning ..."steel cable rigging" and "crane load rigging" will give even more ....

:E

[burger]

I suggest doing a basic riggers course. It will help you understand what it is you ask and more. The basic course will take 2 days.

The rule for finding the safe working load for a wire rope in kg is - square the ropes diameter then x it by 8. Eg: 20mm x 20mm x 8 = 3200kg or 3.2 tonne.
Then you use formulars to deduct the weight it can lift depending on how the rope is wrapped around the load compaired to a direct lift from a lifting eye on the load.

If there is more than 4 strands of a core of rope broken it is U/S. Same for kinks in rope or a deformed eye or hammer lock joiner.

One thing that catches most people out is that they think having a swivel hook alleviates the need for an actual load bearing swivel. It doesn't as the swivel hook is only to help positioning of the hook for attachment to the load lifting point. Not to stop the load spining and unwinding the rope sling.:ok:

[170']

HI 3top

ASME B30.9 (slings) is the manual you need...

I can't find my copy, but it's accepted by OGP auditors as the bible for seismic ops. Particularly in your area, and further South. No-one really wants to touch the subject of kinks, and it's not addressed in the manual as far as I remember. Except under the general clause of ' some common sense required'...

I generally tell the 'support staff' to attach dubious slings to the hook on a backload and then I quietly punch them off into the boonies...It gets rid of the problem without having to draw a line in the sand...If you know what I mean?...And I know you do :ok:

Hope all goes well!....170'