This warning was from a major caravan repairer (who knows his stuff) on another forum
and is worth repeating here, it could save someone's life, see below;

"Another incident of a totally severed 'A" frame this week. At least six thru the workshop in the last couple of months.

This poor bug... had set of on the trip of a lifetime - second day in, as he was reversing into a caravan parking spot, the 'A' frame greenstick sheared on both sides. The van hit the deck and the holiday ended very abruptly. Thank God it happened in a van park and not on the Bruce Highway at speed.

All of you have vans built over the last 8 or so years should have a very good look at the 'A' frame of your van - check it for cracks or distortion, rust streaks that might indicate a crack forming. Check if the 'A' frame has an under truss fitted, if so is it intact at the connection points. Check for tears in the welds or rust marks within or adjacent to the weld. Line the van up against a straight edge and check if the 'A' frame has bent upwards - even slightly. Use a string line if you know how to.

Don't think that because your van has been built by a well know or allegedly reputable maker that you are immune. The converse is more likely the case and it is very likely your van that will have the problem rather than a custom designed unit.

The problems of this type that we are seeing most of are showing up predominantly within the single axle van range, made by well established builders who are building their product to the absolute minimum standard. Mostly very pretty units with absolutely no structural substance.

Why are they allowed to do this ?? Because the standards are bull.... - they are not enforced or enforceable, nor are they strong enough to ensure that a product can cope with the use pattern of the average caravanner. No one gives a sh.. about the end result as long as the van sells and the cheque is cashed. The poor silly buyer looks only at the name or the cosmetics or the plated weight or some other esoteric item of no real consequence - never at the structure, never at the engineering - never at the pure design of the chassis. No one asks the thickness of the 'A' frame main members. If I told you that some of these pr.... are actually using 2mm, or less, Chinese steel in their 'A' frames would that make you feel comfortable towing your insubstantial show pony down the road?

Have a good look people - if you don't know what you are looking at ask someone who does. Question your builder as to what size main chassis and 'A' frame members he is using. I don't give a damn how small the van is if it doesn't have at least a 3mm, preferably 4mm 'A' frame then walk away. Ditto if the van does not have a well designed and viable under truss - one that is actually designed to absorb the immense stresses placed upon the 'A' frame in everyday use.

Forget the alleged Engineers who certify these things - I doubt that any of them have any concept of dynamic engineering - motion dynamics or stress in motion. These are the forces that are at work on YOUR van so let's hope that you lucked it and found a builder who actually knows what he is doing - and has a conscience."
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