Yes Virgiania safety chains do work!

Last week while towing the race car my trailer popped off the ball; there was this loud bang bang bag scaaaaaaaaaaaaping sound. We were traveling about 40 mph, the chains held but they were set long enough to let the nose of the trailer drag the ground. It's an open trailer and in the heat of the moment I got on the brakes just a touch to hard (my poor wife got scared and shouted, which had me shouting back "I know"). The left front fender hit the spare (tow vehicle is a van with spare hung on rear door), it didn't dent the fender to horribly but it also tweaked the hood. It looks OK from 5 ft but I'll need to respray the hood and fender.

I'm not sure why it occurred but I was up till midnight on Thursday (I went to gas everything up before having to set off early Friday) going through the mechanism making sure it wasn't  ever going to come off again. It's possible the slider pin was sticking so the ball wasn't fully forward. I now have a safety pin which won't even allow the mechanism to release even if you pull up the latch.

In almost 30 years of towing I've never had this happen; I always use safety chains but never gave them a second thought until now. I normally gas up in the morning, right before I get on the freeway............yikes!!!

About ten years ago I had a holy E36 M3 moment like yours. Going about 40 mph a car pulled out from a side street causing's me to hit the brakes, no issues untill I steeped on the throttle. And then..

SNAP!!!! WTFFWT???!

Scraaaaaaaaaaap....

The pin holding the ball to the receiver broke!! I just let the truck slow down and drug the mess off the road and just happens to have an extra pin.

But yea what a moment. Chain every time all the time.

Paul

Had a senior moment a couple years ago and just plain forgot to lock down the trailer coupler on morning and realized my mistake as I came across some railroad tracks......probably 20 mph but with a 9,000 lb trailer behind a 1/2 ton Suburban it was still a VERY exciting moment.  Had to use the truck jack to lift it back up and back the truck ball back under it.

Last year going across the same tracks I saw a dude with the same problem so I stopped and helped him reconnect his trailer.

Chains are good kids.

I've forgotten to lock down the lever on a pop-up camper once. As I rolled off the driveway lip the banging from the ball slapping around was so loud I thought the rear axle had fallen out and I stopped immediately. Luckily it didn't drop the hitch. Since then I run chains rated for enough weight to dead hang the entire trailer on everything I own.

I was towing a small utility  trailer one time and passed over US Highway 301 near Florence, SC at a pretty good clip .  The intersection was quite bumpy.  Once I got to the other side I started hearing  blam, blam, blam.    Looked in the rear view mirror and could see the trailer repeatedly ramming my tailgate.  It appears I had neglected to flip the coupler lever down when I hooked it up.   It had gone over 10 miles at this point and it only came off because the rough intersection.  The safety chains kept it from creating more mayhem than it did.     

PA requires the safety chains to be crossed, ostensibly to try to cradle the tongue and keep it off the road. 

Just as a reminder, not only should the safety chains be crossed to cradle the tongue but the pull cable on the brake breakaway system should be short enough that it applies before the safety chains reach their limit.