CAA wants improved system to minimise accident risk in offshore oil and gas operations
The UK Civil Aviation Authority is set to commission research into a second-generation "neural-network" helicopter vibration monitoring system (VMS) aimed at predicting drive failures.
The CAA has also launched the final stage of consultation on its proposal to make VMS compulsory in all UK-registered helicopters engaged in offshore oil and gas support operations, and all other helicopters in the transport category above 5,700kg (12,600lb) maximum gross weight.
The new-generation VMS preferred contractor has been chosen from three tenderers, says John McColl, CAA manager certification airworthiness (propulsion), but the contract has not yet been signed. Its purpose is to drive down costs and improve the diagnostic and trend-analysis capability of health and usage monitoring systems (HUMS).
It is particularly the data trend-analysis capability that the CAA wants to see, because in its first generation the HUMS/VMS has mainly been used as a warning device. The CAA, in its argument for mandating VMS, says the HUMS/VMS has provided usable warnings in 69% of rotor and rotor drive systems failures, and in 60% of potentially catastrophic failures.
Justification for mandating VMS has to be convincing, because buying and fitting the equipment costs nearly £100,000 ($180,000), says the CAA, although it predicts the prices of newer VMS will soon be less than half that.
The CAA has been working with the Norwegian aviation authority on the proposal, which was originally intended to apply more widely than oil-support and heavy transport helicopters. The only requirement under European Joint Aviation Requirements, however, is that operators "minimise the risk" of dangerous failure.
The CAA says that VMS is the best means of achieving that aim, and its compromise following the consultation up to this point has been to restrict the proposed rule to a part of the UK-registered helicopter fleet that is already almost entirely VMS-equipped, McColl says. The new-generation VMS is intended to have such improved performance that the argument for making it standard would be strongly persuasive.
DAVID LEARMOUNT / LONDON
Source: Flight International
