WHILE LANDING ON A RUNWAY WITH A DISPLACE THRESHOLD, BRAKING ACTION WAS LOST AND THE PILOT WAS UNABLE TO STOP THE AIRPLANE ON THE REMAINING RUNWAY. SUBSEQUENTLY, THE AIRPLANE RAN OFF THE END OF THE RUNWAY AND COLLIDED WITH THREE SMALL TREES, WHICH DAMAGED THE RIGHT WING. AN INSPECTION REVEALED A LEAK IN A BRAKE LINE FITTING HAD ALLOWED THE HYDRAULIC SYSTEM TO BE DEPLETED OF FLUID.