Originally Posted by
BEagle
KC-767I is powered by the GE CF6-80C2, but I understand that even after the RW at Pratica di Mare was extended, the Italian Air Force cannot operate it with max fuel for most of the year.
Quadra-national think-tank comparison of KC-767 (not the old ex-ba aircraft the MoD was offered), A330MRTT and A310MRTT with an equal task requirement at ISA / SL / zero wind showed how poor the Boeing RW performance truly was. The RW was a level 10000ft balanced field and each aircraft was required to land with an hour's average burn to tanks dry (simulating an alternate aerodrome requirement) and the reps were required to calculate the max fuel available on take-off. The first thing the US rep said was "Can we make it 12000ft?" - which was refused. As the Boeing rep told us during FSTA times "Yes, that's where we think Airbus has us beat"...
Presumably the KC-46 has uprated engines and uprated brakes if it can really operate from an 8000ft balanced field within normal certification limits? Or was 8000ft the take-off ground roll?
KC-46 has uprated Pratt, not GE engines, and has a bit more wing than the KC-767 (KC-767 has a -200 wing and KC-46 has a -300 wing). And no, 8000 ft is not take off ground roll. And, oh yeah, no thrust reversers. I think the latter is foolish, but presumably the USAF planners know a quite a bit more than I do. Or maybe it has such a powerful braking system (it has the -300 brakes on a -200 fuselage) that it needs no thrust reversers, which could perhaps account for the improvement in balanced field length. I'm not familiar with those particular details. So maybe designing a "franken tanker" was really not such a bad idea after all. And on the subject of "Franken tanker", the 767C2 airframe is the 767-200LRF airframe, which mates a -200 fuselage with -300 wings, landing gear, engines, etc. So all those "franken" bits were put together and certified well before the KC-46 came into being.