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Source for larger tie-down rings?

Paul Eastham

Well Known Member
Landed at a fairly remote airport with winds 25G35 and forecast to increase. Get to the tiedowns and can't get the chains to fit through my (stock Van's) tie-down rings -- the opening is too small. Also can't hook the ends of the chains on -- the ring is too thick.

In retrospect, this is nowhere near the first time this has happened to me, just the first time where it really seemed to matter as I was actively worried about the airplane blowing away. I did have some chocks with me which saved the day, though not in a way that made be feel really comfortable.

I see some other rings on Amazon but the opening all seems to be about the same size (1"), and the cleaveland "ring" has an even smaller opening, though I can't tell that ring's "thickness" - i.e. can it accommodate a hook with a small opening.

Surely I am not the only one with this problem? The other solution i am considering is to carry my own tie-down ropes/straps that do fit.
 
Someof our smaller airfields don't provide tie-downs at all, so we need to pack stakes and a hammer, but in your case I think that your own ropes or some carabiner shackles would solve the problem.
 
High-strength carabiner as a transition between the two, for that very occasional situation?
 
High-strength carabiner as a transition between the two, for that very occasional situation?

This - we carry climbing carabiners that we know will fit through our tie-downs, and that gives us a larger interface to whatever we find on the ground….

Check REI or your other favorite climbing supplier.
 
Three for the carabiner ----- I have three of them onboard, with pre cut sections of rope that have come in handy more than once.
 
An Alternative Approach - MYO

I made my own tie down rings for the reason given above - needed a bigger ring to accept any/all tie down chains encountered on parking ramps around the country. Just simpler for me to have a "one size fits all" solution.

Two sizes - 1 1/4" & 1 1/2" i.d.

The one in the center was pull tested to 1600 lbs. The deformation was significant, but there was no failure.

HFS
 

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There are many options for tie downs - various combinations of webbing/rope/buckles/hooks etc. I use Ancra motorcycle tie-down straps, which work fine and are economical. As a starting point how robust do tie-downs have to be? What kind of working load and strength does the entire system have to be?

I note that the Cleaveland SS tie-downs have a limit of 2000 lbs, but they note in their testing that the tie-down blocks in the wing would shear at 1500 lbs.
 
Thanks all, the carabiners sounds like an easy solution. "Why didn't I think of that?"

I do have a set of fly-ties, ropes and hammer but do not like to carry it unless I'm going somewhere unimproved. They are heavy and dirty.
 
Presumably the chains are affixed to something on the ground. I just carry three ropes and use them through the tie-down rings and whatever the chains are attached to. Lightweight, easy-peasy (except for having to remember how to tie a double locking half-hitch each time LOL!).

Sometimes I settle for the chains if there's no wind predicted, but I don't really like them...dirty, can't usually make them the proper "snug" amount, etc.

The ones I *really* don't like are the chains that are attached to the cable, but free to slide along it. Worst design for tying down planes one could think of, IMO.
 
Thanks all, the carabiners sounds like an easy solution. "Why didn't I think of that?"

I do have a set of fly-ties, ropes and hammer but do not like to carry it unless I'm going somewhere unimproved. They are heavy and dirty.

I would caution against a climbing carabiner. Most are aluminum and while light and strong will quickly wear against a steel ring if there is any relative movement. (I almost lost a boat once when I used a "temporary" 'biner on a mooring line. Within a week, the carabiner had almost worn thru.)

Consider climbing slings. Loop one thru your tie down ring and you can connect any size chain to it. Something like this works:

https://www.rei.com/product/755451/metolius-18mm-nylon-sling

Probably lighter and cheaper, too.
 
Tie-down ropes: don't leave home without 'em.....

Hmmmm...

I've been flying long enough and been in enough situations that I don't go ANYwhere without tie-down ropes and stakes. The light-weight titanium "dog tie" stakes that were available years ago sit in SuzieQ's baggage compartment. Even the heavy-weight ones (eg, Claw, etc) are 7-8 pounds and are worth every ounce when needed. There are a set in the baggage compartment of the J-3 as well. There has been more than one time I had to land in a field, tie down and wait for a storm front to roar through. Easier in a Cub? Yes; but the point is when you need them and they are not there, it could cost you your airplane....IMHO...........:)

There was the time coming home from OSH in SuzieQ along with an RV-6 and a Navion that we hit a wall of weather and got on the ground at an airport JUST in time. I had ropes in the back and, taxiing up to the tie-down area, noticed there was nothing except ground loops. I jumped out and yanked the upwind wing down first, then the tail, then downwind wing and all heck broke loose: heavy Rain with gusting winds. I got soaked heading to the FBO. A WAY too near lightening strike took out the electricity at the FBO. (They sent us a bill for the fuel.) In an hour it had blown through and the "other side" was clear to Colorado. If I had not had those ropes.....:eek::eek::eek:
 
I would caution against a climbing carabiner. Most are aluminum and while light and strong will quickly wear against a steel ring if there is any relative movement. (I almost lost a boat once when I used a "temporary" 'biner on a mooring line. Within a week, the carabiner had almost worn thru.)

Consider climbing slings. Loop one thru your tie down ring and you can connect any size chain to it. Something like this works:

https://www.rei.com/product/755451/metolius-18mm-nylon-sling

Probably lighter and cheaper, too.

While I don’t doubt your boat experience, I’d point out that if your airplane is moving around at the tie-down as much as a boat moves at a pier, you’ve got some real problems! Airplane tie-downs should be considerably tighter.

I’ve been climbing and doing vertical work in caves since the days of steel pitons, and never had a problem with aluminum ‘biners clipped in. I’ve also been using aluminum carabiners for tie-downs for decades, and never saw an issue.

There are, of course, many ways to skin this cat, but for overnights and a week-long fly-in event like Oshkosh, I doubt you’ll have a problem with aluminum ‘biners. At least I haven’t.

Paul
 
Tie-Down Strength?

There are many options for tie downs - various combinations of webbing/rope/buckles/hooks etc. I use Ancra motorcycle tie-down straps, which work fine and are economical. As a starting point how robust do tie-downs have to be? What kind of working load and strength does the entire system have to be?

I note that the Cleaveland SS tie-downs have a limit of 2000 lbs, but they note in their testing that the tie-down blocks in the wing would shear at 1500 lbs.

Interesting. I would also like to know what the recommendation is for strength. I've considered carrying a set of ratcheting tie-down straps--on more than one occasion I've arrived at an airport to find one or more chains missing, with just the in-ground rings present. Yes, I know that I could carry rope, but the ratcheting straps seem pretty convenient. The above post suggests that the ring-to-wing attachment would fail at 1500 lb. On the other hand, I note that Aviation Consumer recommends a breaking strength of 5,000 lb or more for tie-down ropes. I see straps available from several sources with breaking strengths in the 2,000-2,200 lb range. I also see some with ~5,200 lb breaking strength. However, the stronger straps are 8' long, while I find those in the ~2K range with 15' lengths. In many cases 8' would probably be sufficient, but sometimes not. Thoughts, e.g. is a 2K breaking strength sufficient?
 
If straps have a hook end rather than a closed loop end, they are unacceptable as airplane tiedowns. The hook can open up, and falling off. I've seen that.

Also if they are nylon or polypropylene, they are too stretchy and can let the plane start bouncing in severe conditions. That can lead to dynamic overloads and the rope or strap moving off the ring or down a strut or something.

Dave
 
Thoughts, e.g. is a 2K breaking strength sufficient?
Cleaveland seems to think so. I assume they’re thinking that if the wing blocks sheer at 1500 pounds, not much point in having their tiedown points break higher than that. I suppose we can look at straps in the same light.

I use motorcycle tie-downs with buckles, not ratchets, just because the ratchets are kind of bulky to carry around. Otherwise, I would guess they’re probably fine.

The straps that I use have a maximum breaking strength of 4000 pounds, but the buckles and hooks are rated more like 1500 pounds. In calculating the “safe working load“ they apply a safety factor of somewhere between 3:1 to 5:1, so the working load of the straps I use is listed as 400 pounds.
 
A couple ropes in the back are easy insurance you always have something to tie down your plane. I don't leave home without them.

There are a number of places I've been that have tie down locations, but no ropes/chains. Or the ropes that are there don't look like they would hold their own weight.
 
If straps have a hook end rather than a closed loop end, they are unacceptable as airplane tiedowns. The hook can open up, and falling off. I've seen that.
Dave

I worry about that too, but I suppose you could combine with the carabiners mentioned elsewhere in this thread to make sure they don't come off. Then nearly everyone in this thread will have something to be nervous about :)
 
If you keep them really tight, they won't more much, and the chafe problem is lessened. If you don't keep them really tight, then you will get the plane rocking or bouncing and perhaps damaged with the overloading.

Dave
 
If straps have a hook end rather than a closed loop end, they are unacceptable as airplane tiedowns. The hook can open up, and falling off. I've seen that.

Also if they are nylon or polypropylene, they are too stretchy and can let the plane start bouncing in severe conditions. That can lead to dynamic overloads and the rope or strap moving off the ring or down a strut or something.

Dave

Stretchiness is one reason I use straps instead of rope.

It would be easy enough to cut the hooks off and put a non-climbing carabiner in the webbing loop but some of the in-ground tie-downs at some airports can be recessed enough and thick enough that slipping a carabiner on is more cumbersome than I’d like. So far, I’ve just stuck with the hooks and make sure the straps are pulled up tight.
 
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Carabiners, slings, and “line”

I use the (climbing) slings for those cases where the tiedown eyes are too big / buried too deep, carabiners on either end, and small diameter, high performance / low stretch line ( used for sailboats, etc), with multiple loops for length adjustment and strength needs. That type line will not absorb much water at all compared to nylon straps or “rope”, and nylon can lose up to 20% of strength when wet.

If you use regular, hardware store, nylon rope, think about the stretch prior to failure. At 25% elongation, a 4 ft. run will stretch 1 foot prior to failure. That would be a lot of bouncing, and thumping going on, with everything “holding” and tight.
 
Carabiners, slings, and “line”

I use the (climbing) slings for those cases where the tiedown eyes are too big / buried too deep, carabiners on either end, and small diameter, high performance / low stretch line ( used for sailboats, etc), with multiple loops for length adjustment and strength needs. That type line will not absorb much water at all compared to nylon straps or “rope”, and nylon can lose up to 20% of strength when wet.

If you use regular, hardware store, nylon rope, think about the stretch prior to failure. At 25% elongation, a 4 ft. run will stretch 1 foot prior to failure. That would be a lot of bouncing, and thumping going on, with everything “holding” and tight.
 
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