mickjoebill:
It appears that nobody has picked up your point so perhaps I might: it is the policy of some oil companies to move to liferaft installations that provide automatic deployment. In the case where there is a requirement for two liferafts (any FAR 29 certificated aircraft), external attachment will provide a liferaft on each side of the aircraft; in all but a controlled ditching, this raises the possibility that one or other of the liferafts will not be available. Certification (and in some States operational rules) require that on a two liferaft installation the smallest of the two must hold all possible occupants in the overloaded state. There are therefore substantial benefits but there is a down side - i.e. not all incidents/accidents arise from a controlled ditching. Some of the more flexible systems have internal liferafts with external deployment - these are not automatic (but are usually controlled from the cockpit). The benefit, the liferaft can be removed from its fittings and deployed from the best exit. I am not aware of any light helicopter which has automatic deployment.
There is some irony about this discussion on sea state; if one was to examine the SEA STATE CODE that is provided in AC 28.801-1, it can be seen that a sea state of
5 is indicated when the wave heights are 8ft to13ft. Bearing in mind that
none but the latest helicopters like the S92 and the EC225 and probably the AB139 are certificated to more than sea state
4 such a sea state for an adverse weather policy (for singles) might be a little liberal. Singles with emergency floats are rarely certificated for ditching (ditching is considered to be a controlled entry into the water) and when the floats are tested it is usually to sea state 1 (about four inches or 10 centimetres) - they are not tested for the entry procedure although it can (probably) be assumed that the floats would stay attached and survive the autorotation. However, remember what was stated in earlier posts - survival of the entry procedure is only half the battle; once out of the helicopter, water temperature, wind effect (leading to breaking waves and sea spray), clothing and the survival equipment all then come into play - the criteria for examination of those - that the survival time exceeds the rescue time (hence the point that SASless is making on SAR).
I’m sure we all welcome the statement of helirider on the policy of Total and Agip; the comments by Hippolite on the future policy of Shell are also noted although his remarks on the GOM
In future, there will 2 GOMs, one with new generation IFR twins and one with older single engine aircraft. The problem will still be a lack of FAA oversight and regulation, poor comms (somewhat alleviated by systems like outerlink) no adequate IFR system, unmanned helidecks in an unregulated helideck environment etc.
are still difficult to understand in the light of the accident record over the last two years.
Lumped into the second category will be those who have new twin equipment but who choose to operate it Part 91 because they themselves are an oil company and can do it that way.
It is also not quite clear to me why an oil company which operates for itself under Part 91 would not do so using industry best practice.