Question about doublestack intermodal

I’ve seen close-up photos of doublestack intermodal cars, like this one
for example http://www.railfan.ca/cgi-bin/view.cgi?image=Scotch_Block_21.05.04_2409.jpg

and it looks like top container is not secured in any way, just placed on top.
Are there any hidden straps anywhere ? It would seem to me that on hard turns or sudden braking container can at least shift if not fall off completely.

I guess by the nature of my question one can guess that I am not a pro [:)]

Yes M.W. is right. The top box is pin down to the bottom box with a pin that is turn a 1/4 of a turn to the bottom. The bottom is pin to the car. Not much but think? Their is a bout 2 inch pr wheel on the rail a given time.

I guess that mounting method is fine…the only time would be a problem would be if the train left the rails, then gravity would take over…Dave Williams http://groups.yahoo.com/group/nsaltoonajohnstown

Funny that you should mention that. A few years ago, a drunk driver slammed into the middle of a hot intermodel in Oakwood, GA. It managed to cause a derail and sent quite a few containers cars and containers flying. The cars stayed pretty close to the tracks, although they completly stripped everything down to roadbed.

The scarry part was those containers that just went sailing! Some of them must have gone over 100 feet! I remember one that busted open and you could see the paper products. Another had refrigirators. What is incredible is that they all went to the right side where there was nothing, but grass. On the left side was a house that sat right on the right of way. I can’t imagine what it must have sounded like in that house, and I would hate to think what loaded containers hitting a house at sixty miles per hour would have done!

Did SP or UP sell those SP (SPDU) containers?

Large storm waves have been known to knock containers off from ships at sea. Probabily the most notorious example was a container of athletic shoes lost a sea in a storm many years ago. Since the location of the ship was known at the time of the storm, and since athletic shoes float, researchers were able to understand a lot about Pacific ocean currents by recording beach sitings of that particular shoe.

dd

How are smaller containers attached if they are on top of a longer container.( i.e There are no corners to attach the pins.)

The second link has a good explanation of container stacking in the “Movement by Rail” section.