A pilot should be checking his deferred defect log and if any MGB HUMS related defects are noted he should be demanding to see the trend graphs for his own piece of mind (and question them). No matter how good an engineers pre flight or pilots walk around, We are not able to detect the state of play inside the most crucial part of the machine through normal visual inspection. Only HUMS can do so and if there is a rising trend above a threshold that raises concern then a pilot should be quite within his rights to refuse that aircraft.
This is an interesting issue. At present HUMS data is used only to support the Continued Airworthiness of the helicopter and not employed operationally in the sense that the MEL is at the moment.
The implications of this is that the Flight Crew do not at present have the ability to manage the totalily of risk when applied to the actual flight requirement, as you would do say for an deferred defect that might affect the type of flight you need to carry out.
Whether this is viable/sensible for the future is a far wider debate.
What may be more appropriate (and I have no expertise at all in this area) is whether sufficient HUMs data was being picked up immediatley prior to the failure that, if it had been made avialable to the crew, they could have taken immediate intervention to prevent the full catastrophic conclusion that we have just witnessed.
Should/can certain types/levels of HUMS data be provided to the crew in the form of a warning/alert system that, allied to a specified in-flight abnormal/emergency procedure, would prevent such an incident reaching its ultimate conclusion.
Are there any experts in the HUMS field out there who think such a system is viable and in particular, is the databank of alerts sufficiently developed to provide appropriate thresholds for warning and intervention?
DB