What would have happened if the trim spring that broke, had broken in flight ?
Good question. On the canards with the GU and/or Roncz airfoils, the aircraft (theoretically) trims itself to about 125 KIAS. A couple of folks have tested this on purpose and they do seem to have found that the self-trim IAS is somewhere in the 110 - 140 KIAS range. So that's where OUR canard aircraft want to fly, if you remove the trim springs. This implies that IF the trim spring disappears, cruise isn't so much of a problem but the aft stick force to slow down for landing would certainly be substantial, and you wouldn't want to have to pull that hard for very long (but it IS doable).
Where does Raptor want to fly with no trim? An aero analysis could probably predict approximate "elevator zero hinge moment" IAS, but I'm going to guess a WHOLE lot faster than 110 - 140 KIAS, given what Peter said about how much trim force he was using at 80 KIAS or so, with the CG nowhere near the front limit.
So then the question is, how much force (sans trim) is necessary to maintain the 75 - 80 KIAS landing speed that he used in the first flight. No clue. If it's 10 - 15 lb of pull, it might be possible for the pilot to deal with it for the 30 seconds it would take to land. If it's 50 lb., well, that's a different story - you're essentially wrestling with the plane at that point, and the landing wouldn't be pretty.