The failure of fan blades in a locomotive engine

Let me again state that I have concerns with the ATSB's approach and rigour with dealing with the REPCON process and it's assertions that the regulations would include a rigorous and robust approach to ensuring that the system isn't abused. Given the limited information available it is unclear to me how this REPCON could have been assessed under the requirements of the regulations.

Notwithstanding, I will endeavour to respond based on the information available to me from the complaint received. We did have a locomotive suffer a mechanical failure. This event is still under investigation and no conclusions can be drawn at this stage. The incident will be investigated and any recommendations to mitigate the risk will be risk assessed and considered. Unfortunately, the failure did lead to consequential failures of a number of fan blades.

Specifically:

No debris breached the vestibule walls and the crew while in the cabin of the locomotive in motion are well protected from the risk of this type of mechanical failure. No injuries resulted and at no stage were the crew exposed to this risk.

In all circumstances, entering an engine room while the locomotive engine is in operation is dangerous and exposure to these hazards should under all circumstances be minimised.

The common experience all operators share is the risk of mechanical failure as stated.
One high consequence risk present in every locomotive is catastrophic mechanical failure. This risk is always present, although we endeavour to eliminate this risk through our maintenance regime. Inevitability, this hazard can occur and exposure to this risk must be minimised by avoiding, or limiting access to the locomotive engine room. Our procedures will always recommend minimal access to the engine room and recommends avoiding access while the engine is in operation, particularly when powering.

There have indeed been incidents across all operators where a mechanical failure has triggered a catastrophic mechanical consequence and a chain reaction of consequential damage. These incidents are rare and to my knowledge, fortunately have not resulted in injury. However, this experience does not preclude the possibility.

Disappointingly, we had an incident where consequential sequential failures occurred.

This incident's cause has not been identified. We believe we are close to identifying appropriate prevention strategies.

Whenever such incidents occur, we do undertake investigations to gain learnings that will reduce and mitigate any risks. We are always vigilant to these risks and minimise exposure. To this end, we recommend minimal access to the engine room in all circumstances. Whenever the locomotive is powering, which is the greatest risk of mechanical failure, crews should always remain in the locomotive cabin, which is the most protected part of the locomotive and has emergency egress as well as many measures to protect staff in an incident of any kind.

It isn't possible or even prudent to ensure that these types of failures are contained within a locomotive, unlike jet aircraft engines which are designed to contain a catastrophic failure so that materials ejected either forward, or more likely to the rear.

This is because of the heightened risk associated with piercing a pressurised cabin.

Locomotives have different risks. The engine room must vent and have the ability for heat, and fumes to discharge, otherwise other risks are introduced; a "BLEVE" for example (boiling liquid expanding vapour explosion). The side walls have ventilation.

There are design features to slow down projectiles, to reduce the velocity and absorb energy, but reduce risks that can be introduced when the area is totally sealed. A similar design feature to crumple zones in collision mitigation. We are satisfied that no high velocity projectiles exited the locomotive body, which could have been a risk to the surroundings or "passengers".

Any mechanical failure does have "potential" risks to passenger trains, however what the caller failed to identify, was that the DIRN [designated interstate rail network] between Melbourne and Adelaide has only one or two passenger trains per week, which rarely cross our trains. Most of the track is dedicated to freight and little exposure to passenger station platforms and almost no exposure to platforms when passengers may be there. The nature of the operations almost eliminates exposure to the general public.

The complainant appears to not have understood the risk exposure present or the design features that minimise the risks to all.

We will continue to maintain procedures that minimise the risks associated with entering the engine room. We have a number of design features to reduce the consequences of a mechanical failure. We will continue to investigate the fan failure and endeavour to identify and eliminate the risk of a future failure of this type.