Well to understand the whole issue it would help to understand the "bird" in question as well. The ref says it'll fit 2 HMMWVs but I believe the JACKAL is both wider and taller so it might not fit into the ramp opening. It does provide load weights but these are for the newer U.S. CH-47E/F versions. And the answer to the UK CH-47 lift issue is in the "related links" section concerning an engine upgrade, crash and MK 3 version going to Afghanistan. This goes back to the ? I had on the UK PUMAS that got new engines last year at the same time. With helos it's about PTLS, Power, Tilt, Lift and Speed
basically.
http://www.airforce-technology.com/projects/chinook/
Next covers more on the older versions.
http://www.military-today.com/helico...47_chinook.htm
Ref B does indicate a max. payload of 10.3 tons, and does give the RAF payloads in kg for the MK 1 versions, again see the first ref as noted. I suspect (And hope!) someone did the math correctly in dealing with standard weight&metric conversions for load capacity assuming yes, this looks more like an issue ICO the UK a couple of mods to reflect both the CH-47HC MK2 and current CH-47HC MK3 versions into the game. If weights are messed up...well that'll be a big mess, but I've always been an optimist.
Regards,
Pat