Quote:
Originally Posted by up9018
Dairy farms aren't generally built on paved roads, and the bridges on those roads aren't the best. So in my experience, those were put on there more for ground pressure rather than legal scaling issues.
Chris
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Quote:
Originally Posted by frizzen
Jet-A is 6.66 lbs/gal. That fuel truck spends its working life on a ramp that was rated for 747s at max takeoff weight, the 767 its under won't ever come close to that. As long as the axles are rated for it, it's good. That style is usually single or tandem axle. I think single might make it more maneuvurable for ramp traffic.
Normal fuel semi trucks take fuel from refinery or local storage to airport fuel farm, then this kind goes from the fuel rack to plane. Sorry if this was too much of a thread hijack.
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Correct by both guys. Most trucks that have a bunch of axles are for road-loading regulations (aka bridge laws) for the roads they travel, it's independent of the GAWRs the truck is built with. For a single drive axle, GAWRs of 19k-23k are pretty common, yet almost all states limit the weight of a single axle at the GAWR, or 20k, whichever is lower (steer axles are generally quite lower on GAWR). If you've ever seen the cement-mixers with that funny drop-down axle-arm hanging off the back, that's to satisfy a bridge law for that region.
Then of course, if a truck's vocation requires it to have extra axles to avoid getting stuck, the manufacturer or bodybuilder puts them on, to make sure they can continue selling trucks into that job.