"xerj" wrote in message
...
I remember coming across the answer somewhere, but I've lost it.

Anyone know?

TIA

The aerodynamic factors inherent in a tailless delta wing planform are
complex, but basically the trailing edge of the wing has designed upsweep to
compensate for any longitudinal negative pitch moment produced by the
difference between the cg and the aerodynamic center of lift normally
handled by the horizontal tail downforce.
Dudley Henriques