Tony, you might also do a search for the SIA 747 got a/b 30 kts too slow as the loading figures were put into the FMC incorrectly.(Rumours ---tail-scrape-recently).
From personal exp, flying C-130, I picked up a full load of mil. frt. in Idaho to go to GooseBay, and we did all the figures , co`s leg, new co, not MJ( don`t recall he was young!), and of course as ever, we have a bunch of Trappers, trapping Trappers trapping us, as is usual in the RAF.
We get a/b ok and climb out towards F230, but at about F150 I begin to get a feeling it`s not working out,so we level out and let Albert get up to cruise.I do a little flying and can feel it is rather sluggish. So, we all go back through the paperwork, perf etc etc, with all the trappers looking-on, and we decide we are about 12000 lbs overweight.The navigator is busy with his box of bones, and we decide to continue , gaining height where we can; fuel is ok, as normally the graphs are pessimistic.Reaching that place G-B, we offload all the freight for a re-weigh, which is not popular, but in the end it is justified by every other pallet, about 4000 lbs different from the manifest. This was because there were two lines loading freight, one US, and one UK.
Any way I won`t embarass our Allies, and fortunately we were first in the trail. Fortunately, also, that Albert can take quite an overload, and still fly safely,as when we had tankers they were operated up to 20000 over normal maximum.
