212man said:
Sox6, good question and one I've pondered over! I suspect it has more to do with factors unrelated to the certification standard
Yes, internal politics and procurement issues do play a part. The EC155B is only used by Shell in one location - Nigeria. These are owned by Shell and their partners (the majority stake is actually owned by the national oil company NNPC, not an oil company that invests heavily in safety). If the EC155B were in category D it would be far more difficult to get the funding to replace them. However, if the EC155B1 is not in category D, then there would just be one medium option, the AW139, and thus no competition, which would be unacceptable commercially. If this makes you think Joseph Heller deserves a writing credit for 7/7=1 then you are beginning to realise the tightrope being walked.
To answer a couple of PM's I've got, it is for this very reason the mooted down-categorisation of the S-92 due to its MRGB is unlikely to formally happen as that would leave just the EC225 in category D. Instead certain new euphemisms have been invented to convey displeasure in the OEM and their aircraft.
On the horizon is how the EC175 is categorised (is it another D or the first E?). If the former, expect to see the 'EC155' only appearing in category D in future (leaving the AW139 and EC175). However if an all new "post-7/7=1" aircraft like EC175 doesn't reach the level desired for category E, then a major part of 7/7=1 will have failed. Catch 22 again!
I wonder if the category will ever be made public anyway. After the accident in January, Shell Oil, one of the reluctant twin half-sisters in the Shell family, have been exposed to some flack because of this paper's claims about the big risk reduction of going from category C to D versus the modest cost increment of just 15%.
Scotsheli - I am totally serious, it is a major part of the Shell aviation safety strategy to be seen as the industry leader in safety and the continual advice that Shell Aircraft gives is what makes our selected contractors safe.