John Tennant, spotted a cow on the line in the cutting on the approach to Falkirk High and made an emergency brake application; he had only between six and twelve seconds to react to the obstruction and apply the emergency brakes because of the curvature of the track. The dynamics of the train, with the locomotive pushing from behind, meant that when the brakes were applied from the DBSO at the front; there was a delay in transmission of the signal to the locomotive brakes to prevent a sudden backlash to the carriages in front; this caused the train to decelerate only slightly. The train hit the cow, an adult Ayrshire weighing , at 17:55 (BST). The impact of the collision destroyed the animal, but a significant part of the carcass, later thought to be a leg bone, became trapped under the leading bogie of the DBSO, lifting it off the track and derailing it. The DBSO ran derailed for approximately and then veered to the left, before running up the edge of the cutting into trees at the top. It then turned on its side, as it was pushed round by the force of the train behind. The second vehicle, after climbing over the rear end of the DBSO, somersaulted end over end, eventually hitting the fifth vehicle as it ran past it. The third vehicle was hit by the DBSO, as it fell back down the wall of the cutting, after rebounding from the trees. The DBSO and third vehicle were so badly damaged that they had to be cut up on site. Casualties were mainly in the two leading vehicles; most fatalities were due to passengers being ejected through windows, being hit by other passengers or by objects as the vehicles were thrown about. The possibility of trains being fitted with seatbelts was raised and rejected, as it was again 20years later after the derailment at Ufton Nervet in 2004. The main focus was that the light axle-loading of the DBSO had led to its being more easily derailed than a heavier vehicle would have been; modifications were put in place to lessen the chances of a recurrence of the derailment. This problem was to be revisited in the Great Heck accident in 2001, where a leading coach of a train being powered from the rear was again derailed by an object (this time a motor vehicle)