the Airdrie–Bathgate rail link when it opened. On 9 June, it was reported that a 1,000-tonne crane would be brought in by road from Carlisle to remove the derailed carriages on 10 June. The A85 at Falls of Cruachan was in effect on a bridge along the shore of Loch Awe and the engineers were looking at a number of methods to alleviate the problems with using such a large vehicle on the road. The carriage left overhanging the embankment was to be recovered by road, whilst the other was to be recovered by rail. A road crane had to be used as there was insufficient room available to use a rail-mounted crane. An option to use a helicopter to remove the carriages was ruled out due to the weight of the carriages at 35 tonnes each. If the crane was unable to recover the carriages, it was planned to winch them back onto the track and recover them by rail. The operation to recover the carriages was estimated to cost £100,000. On 11 June the crane removed the carriage that had fallen down the embankment. Rockfall risk The stretch of line where the accident occurred is prone to rockfalls from the slopes of Ben Cruachan. The majority of incidents occur in summer and autumn, usually originated by sheep scrabbling on the slopes setting small stones rolling which then disturb larger ones. At least two derailments due to rockfalls had occurred previously in the area prior to the 2010 incident. Along with other methods of rockfall risk reduction in the area, in the particular stretch of line from to Falls of Cruachan to , Network Rail also maintains the Pass of Brander stone signals. This is a purely mechanical warning system, independent of the radio signalling system used on the line. It sets one pair of a series of seventeen semaphore signals to 'danger' should rocks from the slopes of Ben Cruachan break a screen of ten thin wires horizontally strung apart. The signals are spaced about mile (400 m) apart over a length of line. Network Rail confirmed on 8 June however that the Pass of Brander signals would not have prevented the 2010 derailment, as the rocks fell from a position about below the wire screen, falling for about before landing on the track, a distance which was not considered to represent a sufficient landslide risk to be