As to the Tests of the Signalling

30. Mr J Jenkins was the Divisional Signal Engineer for the Central Division of the Southern Region. He described the signalling and the examinations and tests that he and his staff had carried out after the accident. These tests included the wiring, the signal controls, the actual head of Signal CW3, and the track circuit AF and adjacent track circuits. He confirmed that no defects or abnormalities were found, that none of his staff on site that night had actually commenced work, nor were any of them in the relay room concerned with Signal CW3. He pointed out that the signalman could only have returned the lever for 
Signal CW3 to normal after the passage of 4G48 if the control relay for the signal was de-energised, which meant that the signal must have returned to danger. He described the conditions that would have had to be met for the description of the train to be stepped forward on the train describer; one was that the track circuit in advance of Signal CW3 had to be occupied, the other was that the lever for the signal had to be reversed. The fact that the description 6G32 had not stepped forward even though the track circuit was occupied, confirmed the signalman’s statement that he had replaced the lever for Signal CW3 after 
the passage of 4G48. He was satisfied by the tests that the signalling was in order and had allowed it to be brought back into use without making any alterations. He could find no record of any complaints about the sighting of Signal CW3, there were no reports of any faults, and, according to his records, the signalling had been correctly maintained. the red and yellow. aspect lamps having been changed on 9th November I981.Mr. C. Hale, the Chief Signal and Telecommunications Engineer for the Southern Region, said that he was satisfied that the correct tests had been carried out and the results showed that there were 
no faults in the signalling which was operating correctly at the time of the accident. He considered that the work carried out in preparation for stage works could not have led to a false operation of the signalling.  

As to the Examination of 6G32

31. Mr. F.R. Picknell, Mr. D.J. Seal, and Mr. P.R. King from the Chief Mechanical and Electrical Engineer’s Department of the Southern Region described the results of the very thorough examinations and tests that were carried out on the locomotive and wagons after the accident. The locomotive had been badly damaged in the collision and the controls had suffered further in the effort to release Driver Walton. The tests of the wagon and vacuum brake equipment showed that it was in working order and this fact, combined with the evidence of the examination and brake test at Three Bridges, the stop at Redhill, and the absence of any ‘flats’ on the tyres or indications of an emergency brake application, showed that the wagon brakes would have operated. 
The brake selector switch in the locomotive was set at 'Vacuum Normal' which is the correct position for the type of train being hauled. 
32 The brake equipment on the locomotive bogies was connected to an air supply and a brake application simulated. The leading axle was too badly damaged to be tested, but the brake equipment on the other three operated correctly. The brake controller and all the essential valves were recovered and fitted to a test rig where they operated correctly. The independent emergency duplex brake valve, which vents the air brake pipe and opens the vacuum-brake pipe to atmosphere directly, was intact except for the loss of the handle. The four D.S.D. floor buttons were recovered and all operated satisfactorily although one required a heavier than normal pressure to hold it down.
33. Although the power controls in the leading cab, like the brake controls, were badly damaged, making it impossible to determine their position at the time of the collision, examination of the electrical control equipment in the engine room showed that the resistance camshaft was positioned on its final notch. This was the position with all the resistance removed from the armature circuit and the traction motors under power. The field weakening camshaft was in a position indicating that field weakening was not being employed. It was considered most unlikely that the collision could have caused a series of false feeds to the resistance camshaft motor such that it was operated to the final notch. Mr Seal felt that it was probable that at the moment of collision the resistance camshaft was in position 20, as it was found, (ie full field full series). Because of the damage and the fact that battery power was still available after the traction current had been discharged, there was still the remote possibility that short circuits might have caused the resistance camshaft motor to operate, although the motor and the surrounding area of the frame on which were mounted the contactors was undamaged by the collision.
34. There was no sign of a flashover on the motors which might have been caused by a sudden reversal of the controller to provide braking and there was nothing evident in the engine room which might have caused a defect which could either have distracted Driver Walton or caused him to lose control of the locomotive. Tests showed that it took approximately five seconds to shut off power, make an emergency brake application, evacuate the driving seat and pass through the door at the rear of the 
cab, and a further five seconds to reach the diesel engine compartment through the electrical equipment compartment. 
35. I was unable to interview Driver S Walton until 27th October 1982, some nine months after the accident, when he had recovered sufficiently from his injuries and felt fit enough to answer questions. I explained the sequence of events to him that had been established at the public hearing and outlined the evidence that 1had heard before questioning him. However, because of the severity of his injuries and the passage of time, he had no reliable recollection of the events leading up to the collision and only very hazy memories of what he had been doing the day before the accident. I formed the opinion that it would be wrong to use any evidence that he gave although he made great efforts to assist. I felt that there was too great a risk either of my leading him, or of his describing what he normally did rather than the events on this occasion.

As to Calculations and Tests
36. Some days after the accident I carried out two signal sighting and timing runs after dark using a Class 73 locomotive and a saloon. Although Signal CW3 could not be seen from a great distance, a clear view was obtained from a distance in excess of 200m. A driver conversant with the route would have had no difficulty in establishing the position of the signal and, after seeing the restrictive aspects on preceding signals, reacting speedily to the aspect displayed. I was told that the records showed that CW3 had been passed at Danger on one occasion in 1977 by about 20m. Assuming a speed of 30mile/h, the maximum time for 
which a driver could have a full view of the tail lamp and the rear of the parcels train on the right-hand curve in Platform 1 at East Croydon is 10 seconds. In that time a driver should at least have been able to make an emergency brake application and get clear of the cab as the tests showed.
37. Based on the physical features of the line, there corded times for the movements of 6G32 (allowing for signal box clock error), the characteristics of the locomotive and train, and the position of the field and resistance camshafts, speed/distance and time/distance performance curves were derived for the journey from Redhill to the collision. The curves are consistent with the series full field controller position determined from the camshafts after the collision and with the signal box timings. They imply an average balancing speed, for the 6.25 miles from Star Bridge to East Croydon, of 42.6mile/h. 

DISCUSSION
38. From the evidence of the signalman, the indications in the signal box, the tests, and those who saw the aspects of Signal CW3 I am satisfied that the signal was displaying a red aspect correctly as 6G32 approached with the preceding signals showing caution aspects. Similarly there was no evidence of any defect in the locomotive which could have led to Driver Walton losing control completely so that no warning or brake application was possible. 
39 There are two other factors that must be considered. One is that Driver Walton appears to have been completely unaware of the signal aspects or the possibility of a collision; he was in his seat, the brakes and horn had not been used, and it seems probable that the locomotive was under power. The second is that the speed of the train does not appear to have been correctly regulated. The guard's evidence and the severity of the collision indicate that the temporary speed restriction at East Croydon was not complied with, two witnesses independently remarked that 6G32 was travelling faster than they expected, and the 
performance curves show that the train was probably driven at or above the maximum permitted speed almost up to the moment of collision and that there seems to ha\,e been no reaction to the single yellow aspect of Signal CW I.

CONCLUSION
40. Because there is no evidence of a defect in the signalling or the locomotive I can only conclude that the accident occurred because Driver Walton failed to control the train in accordance with the signal aspects. I cannot he certain whether this was because he was taken ill, fell asleep, or became distracted. However, Supervisors Morgan and Card, Relief Driver Rowles, and Guard Wenham noticed nothing untoward in Walton's behaviour before the accident; he was conscious after the collision, his behaviour up to the departure from Redhill gave no hint of illness, and the DSD should have operated if he became so ill that he 
lost control. Accordingly it seems probable that he was distracted in some way or fell asleep.

REMARKS AND RECOMMENDATIONS
41. Because of the industrial dispute Walton had been on strike on 13th and 14th of January. He had worked from 2152 on 11th January to 0612 on 12th January and had been off duty on 9th and 10th. He certainly slept on the night of 14th January but was busy at home and did not sleep before leaving for duty on 15th January. This must have disturbed his sleep pattern and may have led to him becoming drowsy. Driver Walton's behaviour in dismissing his assistant is quite inexplicable especially during an industrial dispute. He clearly considered at the outset that he was quite competent to drive the train without an assistant and, if he had felt any later doubts, he could have invited Guard Wenham to travel with him from Three Bridges. Accordingly, although it is possible that the presence of Relief Driver Rowles could have prevented the accident, I do not think that the action of Driver Walton in dismissing him was a direct cause of the accident. A driver's assistant was only rostered under the manning agreement between the Board and Unions because the total diagram was in excess of 8 hours, there were two light locomotive movements, and because no formal ‘personal needs’ break could be included.
42. Although there might have been a risk of Driver Walton automatically cancelling the warning I feel that if AWS had been fitted to the signals he would almost certainly have been alert to the restrictive aspects displayed. This feature has been discussed in a number of Reports by Inspecting Officers and AWS is being provided as part of the resignalling of the Brighton line which should be completed in April 1985. The completion of the scheduled installation of AWS elsewhere in the Southern Region is due in 1987and I recommend that every effort must be made to achieve this date.
43. The possibility that Waltou fell asleep but did not release the DSD raises important considerations. Although with modern multiple-aspect signalling the AWS acts as a form of vigilance device, a risk still exists that the warning may be instinctively cancelled without alerting the driver or will not be heeded and the subsequent brake application may come too late. There will also remain some lines which do not carry sufficient traffic to warrant fitting with AWS. I feel that the Board should examine the effectiveness of the DSD where it is a pedal type and this is in hand.
44. This is not the first accident with which I have been concerned where the guard in the rear cab of a locomotive has been put at risk in a collision by the movement of the contents of the leading wagon. I have considered whether a barrier wagon should be provided but to be fully effective it would be necessary at the locomotive end of all freight trains and its provision and marshalling would create delay and introduce other hazards. I feel that on balance it would be better to concentrate on the prevention of collisions to benefit all train crew.
45. The damage to the leading end of the locomotive was typical of a collision in which the locomotive had dived under the vehicle ahead, in this case a General Utility Van. The structure of the cab had been folded back in such a way that it swept the equipment in the cab back to the bulkhead behind. Some damage was caused within the electrical equipment compartment.
In his report on the collision that occurred on 7th November 1980 at Crewe, Major Oliver notes the assurance that he has received concerning the design of new locomotive cabs to give substantially greater protection to train crews. I support his recommendations that the crew should be instructed to vacate the cab whenever possible and that the Board should carry out a detailed examination into the damage that has occurred to locomotives in head-on and rear-end collisions with a view to quantifying the risk of marking 'safe' areas to which crews should move in such emergencies.