On Monday, 9 March 1998, at about 0655 hours Train 1603, a Masterton to Wellington suburban passenger service, collided with a transition head which had fallen from the locomotive cowcatcher. Damage to the underside of the train resulted in a 3000 litre diesel fuel spillage.
The cause of the collision was a transition head becoming displaced in transit due to inadequate stowage details.
Safety deficiencies identified were:
• The lack of adequate investigation of the work necessary to convert overseas rolling stock for New Zealand coupling requirements.
• The failure of the safety system to prevent unauthorised modification of rolling stock.
The suitability of the fixing detail for stowage of transition heads on cowcatchers was identified as a safety issue.
The Commission investigated this incident because of the potential for derailment associated with the loss of such a heavy and irregular object during transit.