Um, carry more in volume, or in weight? Weight I'm afraid is just not true. Passenger craft hit MTOW far more often than freighters, as explained previously on how freighters bulk out more often than they weigh out.
Payload weight =/= MTOW, Pax craft hit MTOW more often because they often fly far longer routes as cargo pallets don't mind some fuel stops and long-haul pax routes regularly require trading payload for extra range. AFAIK 767 pax A/C do not regularly fly around carrying 40+t of pax + cargo like their cargo brethren frequently do, let alone the 90+t that the 777F can carry.
The 777F sells so well because it was essentially the first good option for long haul freight. If parking spots are the limiting factor, then why hasn't Airbus fast-tracked the A330-800 as a freighter? It's cheap to acquire, far more efficient than the 777F, and fits into all the same spots. The 800 also isn't selling well as a passenger plane.
You answered your own question, in the same parking spot (wingspan), the 777F can carry significantly more payload in both weight & volume (103t vs ~70t, 650m^3 vs 470m^3) than a hypothetical A338F, meanwhile, the 763F has volumes close to a A338F (440m^3 vs 470m^3), a 764XF will easily exceed A338F volume with 6m extra fuselage, not to mention the MD-11F, all fitting in a smaller parking spot (or more planes in the same spot). Fuel efficiency just doesn't matter so much relative to other factors if the plane might not crack 150 FH/month.
Don't count on it remaining 2-3-2. I'm sure it will be 8-abreast, if Boeing chooses the lipstick on a pig route again.
Not that I think the 767 is a pig by any stretch; I've flown many, many hours on them, but they are yesterday's plane.
a -400 does seem to me to be a bit big to compete with the A321XLR; a -200 would seem perfect for that and a viable cheap, quick and dirty NMA, but I suspect it would be too heavy to be competitive. So a -400 would be more aimed, I think, at the A330 market. A -300 somewhere in the middle. A sweet spot?
Given that the 767-400 is already a tad oversized/overcapable for the NMA role to begin with (200t MTOW/5500+nm range), hanging GenXs off it and doing the structural strengthening work for freighter payloads will just make it a homeless man's 788. It's clear this study has cargo as a first priority, the key to this program's success would probably hinge on if this GenX 767 can improve payloads significantly over a plain old B763F.
Last edited by JustSomeDood
on Fri Oct 11, 2019 3:29 pm, edited 1 time in total.