Comprehensive Helicopter safety review

25 February 2014

CAA review of North Sea helicopter safety

This extensive, timely and largely evidence-based review provides wide-ranging and valuable data about offshore helicopter operations in UK and Norway, plus some further evidence from other relevant global operations. Some of its recommendations are highly relevant for other operating regimes and client sectors, notably offshore wind energy. My personal summary, though I’m not a helicopter specialist, follows.

Scope of the Review 

• Wide-ranging, covers all aspects of N Sea operations. Clearly demonstrates the deep expertise needed to operate and regulate such activities to ensure high levels of safety for all involved (i.e. including helideck crew and potential rescuers as well as pilots and passengers).
• Takes account of previous reviews, research, actions and initiatives led by CAA, helicopter operators and oil & gas sector. These clearly demonstrate the long history of design and operational improvements.
• The review process included external review of the draft report by an independent 5-person ‘challenge team’, who fully endorse the report and its recommendations. Though published by CAA, it’s also endorsed by their Norwegian colleagues.


• Many similarities between UK and Norwegian operations. The Norwegian average accident rate is 1/3 UK, but this difference is not statistically significant (i.e. not that many events). Also found no evidence of key differences between operating practices. Norwegian incident reporting rate is significantly higher, more analysis is needed to identify whether this is actually more events, or better reporting due to organisational culture differences – but it’s probably the second.

• A key difference is that the Norwegian aviation regulator takes more of a leadership role, whereas UK CAA has relied more on others to do this. As a result CAA propose to establish and lead a new joint offshore operations safety forum, from Q3 2014.
• Current UK offshore fatality risk per flight for a helicopter passenger is around 10 times the risk for a flight in passenger jet aircraft. This is judged as not acceptable and recommendations are targeted at significantly reducing that risk. Some will take time to implement (3-5 years estimate), so interim measures will also be implemented.


• The majority (32) are for the CAA itself. There are also 13 for the EU aviation regulator (EASA). 12 are for the helicopter industry, affecting design, operations and maintenance, three for the oil & gas clients and one for all parties (funding of relevant research and timely implementation of the results).
• A key recommendation is for helicopter manufacturers to implement a side-floating scheme on all aircraft (or retire those where this cannot be achieved). These schemes will increase the likelihood that, if an aircraft ditches, it will remain floating with an internal air pocket, thus allowing passengers and crew sufficient time to exit.
• By September 2014 helicopter operators must define the maximum sea state for which the ditching performance of each aircraft type is certified, and not operate any non-emergency flight if that sea state is exceeded at the offshore location. In the interim (from June 2014), sea state 6 shall be the maximum permitted, to ensure a good prospect of recovery of survivors. 
• Because the side-floating schemes will take time to design and implement, in the interim there must be additional precautions in place for aircraft without this feature. These include:
o All passengers without an Emergency Breathing System that can be deployed underwater (Category ‘A’ the CAP 1034 draft standard) must be seated adjacent to an escape window. Development and deploying such systems is likely to take 1-2 years, so resulting limits on the maximum number of passengers will be significant for at least that period.
• From April 2015, the body size of all passengers, with required safety and survival equipment, must be compatible with the size of push-out window emergency exits.
• The recommendations summarized above concentrate on improvements to aid survival in the event of a ditching (controlled descent to sea) or crash (uncontrolled water impact). The majority of the others not detailed above are, of course, targeted at reducing the likelihood of such events, and other incidents such as post-crash helideck fires. Also targeted are unjustified variances between client operational requirements and audit processes, both of which can divert resources from flight safety activities.

Personal conclusions (as a non-aviation specialist)

• A very thorough and wide-ranging review. Highlights some weaknesses from the typical UK ‘light touch’ regulatory approach compared with the more interventionist Norwegian arrangements. Also highlights the challenges of moving from national to EU-wide helicopter-related legislation, and the time it can take to agree, issue and implement associated standards, etc.
• Based on detailed understanding and review of the evidence base, plus full support from an independent ‘challenge team’. Other parties currently calling for, or leading, parallel reviews should consider whether continuing these is more likely to result in real safety improvements for the offshore workers and pilots who are at risk, or to divert key resources from working on the CAAs wide-ranging recommendations?
• It is unclear how much consultation and quantification there has been on CAAs ‘low/medium/high’ cost impacts of Key Measures to Improve Passenger Protection (Annex D, Table D2) - none are documented.  But this data is critical when deciding what is ‘reasonably practical’ and setting mandatory implementation dates. It’s also needed to help duty holders prioritise actions on helicopter safety against other improvements to reduce major hazard risks to offshore personnel. 
• One recommendation that seems to be based on very limited evidence (one quoted offshore helicopter fire, S China Sea in 1985) but is listed for early completion (Q3 2014) relates to retrospective upgrading of helideck firefighting systems on normally unmanned installations (NUIs), of which there are 116 in the UK sector. Though such incidents are ‘foreseeable’, the risks appear extremely low compared with those from ditchings – so how is such an early completion target justified? (To be fair, these upgrades were first recommended nearly 3 years ago).

Ian Waldram
March 2014