The intuitive idea of the wing load being doubled on loss of upper wing of a biplane (both upper and lower having same area) is mathmatically correct and practicaly wrong.

There is an effect of mlti-wings where the airflow between the wings has them intterfering with each other's lift production... you lose a portion of you lift based on the airspeed, distance between the wings, chord, and span. The smaller the scale of the aircraft... the worse the effect.

If I remember... isn't the Eagle's lower wing about 70% the area of the upper? That is one heck of a lot of wing to take off of an airplane and then try to fly it. (with no other changes except CG shift) I agree with the one who said... HEAVY warbird performance. (If it has the power to get off the ground)