>>>Any aircraft that weighs more at takeoff than it's permissible landing weight by FAA FAR
must have a fuel dump system.
Can I ask where you came up with this, or cite the FAR
? Our 737-700s can (and often do) takeoff at the max 153,000 lbs, with a max landing weight of 128,000 lbs, and I can assure you that they don't have a fuel dump system involved.
-used- to say that if an aircraft's max takeoff weight exceeded it's max landing weight by more than 105%, then you had to have a fuel dump system. That explains why the 727 had one, and the then-new 737-100 and DC-9-10 didn't. That 105% figure was later dropped (as 737/DC-9 families were stretched starting in the mid-late 1960s, IIRC.
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