Chain Tie down

[brien23]

Proper way to use a chain tie down. I see a lot of aircraft tied down with the hook used to take up slack. I say slip a link through the chain and use the hook to keep it from coming out with slack or weight of the chain on the hook to keep it in place in the wind, Anybody see a link on the web on the proper way to secure a aircraft I see lots on rope but not on chains.

 

[Bob Noel]

For small aircraft, I believe you want something that will give/stretch rather than letting the aircraft absorb all the jerk. Using a chain seems to be a bad way to secure an aircraft...unless you don't care if the aircraft gets damaged. Maybe that's why the shortage of info on chains for tie-downs.

 

[tiger]

Proper way to use a chain tie down. I see a lot of aircraft tied down with the hook used to take up slack. I say slip a link through the chain and use the hook to keep it from coming out with slack...

This is the method the FAA recommends in AC 20-35C. The chain bears the load rather than the hook / fastener.

Their example shows chains used with a 'wire rope' system, so the wire rope would presumably provide some 'give'.

 

[Clark1961]

For small aircraft, I believe you want something that will give/stretch rather than letting the aircraft absorb all the jerk. Using a chain seems to be a bad way to secure an aircraft...unless you don't care if the aircraft gets damaged. Maybe that's why the shortage of info on chains for tie-downs.

No shortage of chains in these parts. Many of them use a long wire cable stretched out horizontally with chains attached to it. The wire cable is anchored at each end and perhaps in the middle and several aircraft can be tied to it. We always passed the chain through the tie-down ring and then pushed a link back into the chain a ran the hook through that link. It's a very strong and low maintenance tie-down system with a long life.

 

[RoscoeT]

Don't use chains

 

[frfly172]

On the chain tie downs I have used. The chain is attached to a wire along the ground. Used the hook on ring of aircraft.tie down had another hook at the wire to take up slack. Fla still uses chain at some airports.

 

[Jeff Oslick]

For small aircraft, I believe you want something that will give/stretch rather than letting the aircraft absorb all the jerk. Using a chain seems to be a bad way to secure an aircraft...unless you don't care if the aircraft gets damaged. Maybe that's why the shortage of info on chains for tie-downs.

Most of the chain setups have the chain secured to a cable, and the cable is the flex in the system. I haven't seen a case where the "jerking" action of a plane secured with cables has caused damage. I have seen cases where tiedown ropes have untied or snapped in high winds, resulting in inverted flight into the ground. When the wind starts blowing 40-50 mph, I much prefer the security and strength of the chains over ropes. Don't know where you fly, but chains are the norm out west, not ropes.

 

[flyingron]

Hooks are lousy devices to rely on. I was given a set of slack adjusting tie downs with S hooks to connect to the plane rings and during the first night at Oshkosh the wind rocked the 172 so hard (and the fact the ground was soggy and the plane sunk a bit) the hooks popped out. Fortunately I had also brought real rope with me and I'm out there in a thunderstorm retying the thing.

I've been in another storm with my "The Claws" that was so bad that the navion BENT the claw. It held but they were pretty ugly looking. The Claw guys replaced them for me (no charge).

 

[Bob Noel]

Most of the chain setups have the chain secured to a cable, and the cable is the flex in the system. I haven't seen a case where the "jerking" action of a plane secured with cables has caused damage. I have seen cases where tiedown ropes have untied or snapped in high winds, resulting in inverted flight into the ground. When the wind starts blowing 40-50 mph, I much prefer the security and strength of the chains over ropes. Don't know where you fly, but chains are the norm out west, not ropes.

Let me see if I understand correctly, your use of chains include a cable to provide some stretch/give rather than just a chain alone, right? In my simple brain, a chain/cable combination isn't at all the same as just a chain for securing an aircraft. And of course, a cable is normally stronger than a rope.

btw, why use any chain at all? why not just a cable?

another btw - the weak link (no pun) in the security of the tie-down is where it attaches to the aircraft (in this case, "security" is theft-prevention).

 

[Bill]

the wind rocked the 172 so hard (and the fact the ground was soggy and the plane sunk a bit) the hooks popped out.

A wrap or two of duct tape over the open end of the tiedown will prevent that from happening.

 

[tiger]

Let me see if I understand correctly, your use of chains include a cable to provide some stretch/give rather than just a chain alone, right? In my simple brain, a chain/cable combination isn't at all the same as just a chain for securing an aircraft. And of course, a cable is normally stronger than a rope.

btw, why use any chain at all? why not just a cable?

The cable runs horizontally along the asphalt / concrete with regularly spaced anchors (that only hold down the cable). The tie down straps / chains / ropes connect to this cable rather than an anchor in the asphalt / concrete. The cable is part of the airport 'furniture' in place of fixed tie-down anchors.

The primary benefit of the system, as I understand it, is that you aren't forced to have the ground end of the tie-down secured at a specific lateral point so airplanes of different sizes / tie-down spacings can be easily accommodated and with less wasted space.

There are picture of this system in the AC I mentioned earlier on p15: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/list/AC%2020-35C/$FILE/Pages11-20.pdf

 

[Jeff Oslick]

btw, why use any chain at all? why not just a cable?

Ever tried to adjust a cable?

I'm kind of surprised these questions come up - I was taught this stuff (how to use various tiedowns) as a student, like learning how to pump gas into a plane.

Exactly the best way to do will vary somewhat depending on your aircraft's tiedown points, chain length, link diameter, etc.

 

[flyingron]

A wrap or two of duct tape over the open end of the tiedown will prevent that from happening.

Having to duct tape and unduct tape my tiedowns doesn't sound particularly convenient. I'll just use rope (or chains that I can use the link to bear the weight and the hook just becomes a safety pin).

 

[Jim Logajan]

I'm kind of surprised these questions come up - I was taught this stuff (how to use various tiedowns) as a student, like learning how to pump gas into a plane.

There are only chains at the airport I learned at and fly out of, so of course use of ropes was not included in the instruction. I'm surprised you are surprised.

 

[Sac Arrow]

I've used chains for the last, I don't know, ten years of plane ownership? Never had an issue. (Never realized it was an issue, everyone uses chains out here.)

 

[LDJones]

Only time I've seen aircraft cut loose during a storm were ones chained down. The roped ones stood fast. Thankfully the missed mine by a couple of feet when the flipped. The chain actually broke the tiedown ring on the Cherokee.

 

[Henning]

I'm not a big chain fan, but when I use them, I bring the chain up taught an 'fold' it so the link I want to pass through my eye is at the top with two sections leading down and stick the top through the eye. The next bit depends on the chain type; either I'll bring the dangling side up and create another fold and stick that link over the link through the eye, kinda like a big fender washer, and then stick the hook through the last bit of the link to lock it all together. If the link design doesn't allow for this, I'll skip the 'washer link' and put the hook though the link directly.

Most of the time though I'll just pull the lines or ratchet straps out of the back of my plane and tie that in. Either that or just have it put in a hangar.

 

[RV10flyer]

We used 10,000 lb cargo straps in the Army. They worked nice and do not come loose.

 

[brien23]

For those of you who only have used ropes only, should you come out west and find only chains on the ramp ask how to use them. I don't want your plane flipping over onto mine because you do not know how to use chains.

 

[John221us]

I've used chains for the last, I don't know, ten years of plane ownership? Never had an issue. (Never realized it was an issue, everyone uses chains out here.)

Yes, out here in CA that is pretty much what you will find at every airport (chains). The only airports I can remember having ropes is Truckee and Santa Barbara. Unless you want to carry your own tie down ropes (and most people don't), you just use the chains. But, on the other hand, it is rarely windy enough to care too much and if it was, my plane would probably be tucked in its hangar and I wouldn't be flying. We don't get typhoons, hurricanes or tornadoes and I haven't seen an earthquake flip a plane over.

 

[Henning]

Yes, out here in CA that is pretty much what you will find at every airport (chains). The only airports I can remember having ropes is Truckee and Santa Barbara. Unless you want to carry your own tie down ropes (and most people don't), you just use the chains. But, on the other hand, it is rarely windy enough to care too much and if it was, my plane would probably be tucked in its hangar and I wouldn't be flying. We don't get typhoons, hurricanes or tornadoes and I haven't seen an earthquake flip a plane over.

I'm surprised Loma Prieta didn't lol. Damn, I got thrown on my ass in Santa Cruz and I was watching the ground wave like being at sea.

 

[John221us]

I'm surprised Loma Prieta didn't lol. Damn, I got thrown on my ass in Santa Cruz and I was watching the ground wave like being at sea.

Ok, that is quite an image. There have been just a few really big ones in the last 40 years or so. They will do considerable damage to structures such. A visible ground wave, though?

 

[Ghery]

I'm surprised Loma Prieta didn't lol. Damn, I got thrown on my ass in Santa Cruz and I was watching the ground wave like being at sea.

Ok, that is quite an image. There have been just a few really big ones in the last 40 years or so. They will do considerable damage to structures such. A visible ground wave, though?

I was on the other side of the mountains when that hit. Sitting in an office in Cupertino. I missed seeing the visible ground wave, but I heard the reports from reputable sources. My house was about 6 miles from the epicenter (Almaden Valley). No structural damage, but it sure emptied the shelves and cabinets. That was one heck of an earthquake.

 

[Henning]

Ok, that is quite an image. There have been just a few really big ones in the last 40 years or so. They will do considerable damage to structures such. A visible ground wave, though?

Yeah, it was freaky, there was even liquefaction of the ground that happened. I was in 3 major quakes if you count Big Bear as a major, and that was the only time I saw rolling swells on the ground.

 

[SoloEqs]

everyone uses chains out here.

I've heard that about the people across the bay from you, anyhow . . .

 

[Palmpilot]

Yes, out here in CA that is pretty much what you will find at every airport (chains). The only airports I can remember having ropes is Truckee and Santa Barbara.

Palo Alto is another one.

 

[Palmpilot]

I was on the other side of the mountains when that hit. Sitting in an office in Cupertino. I missed seeing the visible ground wave, but I heard the reports from reputable sources. My house was about 6 miles from the epicenter (Almaden Valley). No structural damage, but it sure emptied the shelves and cabinets. That was one heck of an earthquake.

In Milpitas where I worked, I had trouble getting the soldering iron back in its holder.

 

[Sac Arrow]

I've heard that about the people across the bay from you, anyhow . . .

Somebody make me a palm in forehead smile.

 

[denverpilot]

For those of you who only have used ropes only, should you come out west and find only chains on the ramp ask how to use them. I don't want your plane flipping over onto mine because you do not know how to use chains.

I saw a transient parked one day that just pulled the S-hooks up and hung them from the tie down eyelets on his Cessna. Hahaha.

Nothing but chains around here. It's the ropes I forget how to get a good knot in. But I have an iPhone app for that. Haha. Kinda kidding. Tie downs I remember but other non-aviation knots... Reaching for the phone.


Sent from my iPad using Tapatalk

 

[timwinters]

For what it's worth I just ran across this article stored in my "airplane sh*t" file on the computer. Thought about this thread and thought I'd share:

 

[Chrisj13]

Climbing carabiners with spring loaded closing gates work well. (Assuming your chain link is large enough for the carabiner to pass through.) the chain/plane can rock all it wants, the carabiner won't open or slip off like an S hook can.

 

[Henning]

Climbing carabiners with spring loaded closing gates work well. (Assuming your chain link is large enough for the carabiner to pass through.) the chain/plane can rock all it wants, the carabiner won't open or slip off like an S hook can.

You can also use a simple shackle.

 

[Dav8or]

The chain actually broke the tiedown ring on the Cherokee.

That's what happened here in Byron when we got some pretty strong winds a few months ago. The tie down ring broke and this plane flipped over. Reported something like 75-80 mph. Really rare in California.

 

[Fearless Tower]

For those of you who only have used ropes only, should you come out west and find only chains on the ramp ask how to use them.

Exactly. I'd say that at least 90-95% of the airports in the Southwest have only chains on the ramps.

 

[Palmpilot]

For what it's worth I just ran across this article stored in my "airplane sh*t" file on the computer. Thought about this thread and thought I'd share:

Some years ago, our flying club started using the knot shown below. I'm told it is called a mustang knot, and that it is used in Alaska.

 

[Henning]

Some years ago, our flying club started using the knot shown below. I'm told it is called a mustang knot, and that it is used in Alaska.

The only thing I don't like about it is that you can't tension it. I like using a rolling hitch and then securing that with a locking hitch. That way in a storm as line gets wet and stretches and the plane starts bouncing you can go and undo the locking hitch, pull the rolling hitch tight getting all the slack out, then re tie the locking hitch.

Also that 'mustang knot' is not a particularly secure knot on purpose, it's designed to come out with a bunch of yanking and jerking.

 

[denverpilot]

I've seen days where the airplanes on the cable with chains at KBJC are all lifting the cable as they pull up on it. Flying on the wire, literally.

Gusts in excess of 100 MPH during certain times of the year are common at KBJC, too.

Never seen a carabiner used there. Just the link pushed through the tie- down ring, another link pushed through that one, and the S-hook being held tight to the link by the downward pressure of the cable.

If there's one mistake folks make with cable to chain systems it's that they don't pre-tension it by lifting it with their foot. Slide the chain so it's the shortest distance to your tie ring and then stick your foot under the cable and lift it. The chain will move about a foot shorter. Put the link through, put the other link through that one, release some pressure to hold it still and secure with s-hook. Release cable pressure and wiggle so S-hook is pulled up right against the link so it can't move.

I could see where a carabiner would be nice (can't bounce out) as the thing keeping the link from pulling through but wouldn't want the carabiner taking the weight. The links are usually much stronger, shear-wise.

The tie hook will tear up the airplane strut before the link-through-link thing breaks.

 

[Henning]

I've seen days where the airplanes on the cable with chains at KBJC are all lifting the cable as they pull up on it. Flying on the wire, literally.

Gusts in excess of 100 MPH during certain times of the year are common at KBJC, too.

Never seen a carabiner used there. Just the link pushed through the tie- down ring, another link pushed through that one, and the S-hook being held tight to the link by the downward pressure of the cable.

If there's one mistake folks make with cable to chain systems it's that they don't pre-tension it by lifting it with their foot. Slide the chain so it's the shortest distance to your tie ring and then stick your foot under the cable and lift it. The chain will move about a foot shorter. Put the link through, put the other link through that one, release some pressure to hold it still and secure with s-hook. Release cable pressure and wiggle so S-hook is pulled up right against the link so it can't move.

I could see where a carabiner would be nice (can't bounce out) as the thing keeping the link from pulling through but wouldn't want the carabiner taking the weight. The links are usually much stronger, shear-wise.

The tie hook will tear up the airplane strut before the link-through-link thing breaks.

The airplane will break before the carabiner does.

 

[denverpilot]

The airplane will break before the carabiner does.

Climbing carabiners yes. I have carabiners around here stamped "not for climbing" that'd shred at the first good pull. But they'd be able to hold the chain link itself in place, just fine.

If done right, the link through link thing -- even if the s-hook pops out -- usually won't also come out, as long as you tensioned the cable. The airplane can't hop enough to bounce low enough to pop them apart since they're under tension.

Most folks don't tension the cable though, and that's where the trouble really amplifies with chains. Just like with ropes, if the airplane can move, you did it wrong.

The other way to do it, is to attach the chains straight up and down and then push the aircraft backward to tighten them up before doing the tail.

If the tail is tensioned properly you're going to end up pulling the airplane backward to get there anyway.

 

[Palmpilot]

The only thing I don't like about it is that you can't tension it.

I haven't had any difficulty in tensioning it. I just pull the first loop in the proper direction before pulling on the loose end.

I like using a rolling hitch and then securing that with a locking hitch. That way in a storm as line gets wet and stretches and the plane starts bouncing you can go and undo the locking hitch, pull the rolling hitch tight getting all the slack out, then re tie the locking hitch.

I'll see if I can Google that.

Also that 'mustang knot' is not a particularly secure knot on purpose, it's designed to come out with a bunch of yanking and jerking.

When I yank and jerk on it by pulling sideways on the line, I haven't been able to make it come loose.