Test Conditions:
B24J
Bomb Load: 8 x 1000 lbs
Fuel: 100%
Flaps: Down 1 notch
Gear: Raised at liftoff
The #2 bomber in the B24J formation out accelerates both the #1 and #3 bombers during the ground roll and gets airborne first. The #2 bomber then passes the #1 bomber. What happens next depends on what the #1 bomber does.
If #1 stays low, #2 and #3 will continue to fly runway heading and will attempt to form up either after a certain distance from the runway or when #1 climbs to a certain level above the terrain. In this scenario there is a danger of loosing both #2 and #3 to the left or right if #1 does not also maintain runway heading.
If #1 climbs at best angle (1 notch of flaps, weak stall horn) and climbs to that certain level above the terrain, both #2 and #3 will attempt to form up immediately. The #3 bomber will form up quickly – close to the end of the runway. The #2 bomber, being in front and above #1, will cut its throttles in an attempt to fall back into formation. But slowing down putts it close to the stall. #2 then goes into a dive in order to maintain flying speed with cut throttles. By the time #2 is behind #1 it is well below the formation and cannot accelerate and climb to get into position. Unless the formation levels (or descends slightly) and slows to near stall speed, the #2 bomber will be lost.
I consider the rapid acceleration of the #2 B24J bomber during the takeoff roll a bug.
MachNix