The MAA have discussed the certification of the Boeing P-8A Poseidon Maritime Patrol aircraft, prior to it entering front line service.

The aircraft first flew in 2009 and entered US Navy operational service in 2014. It should be noted that whilst the Poseidon’s heritage is from the Boeing 737; the aircraft are designed, certified and built as military aircraft and are not civil airliners modified for a new role.

MOD Defence Equipment and Support (DE&S) are responsible for acquisition of the Poseidon aircraft, associated systems and support through a Foreign Military Sales contract with the US Department of Defense. Like all new United Kingdom (UK) military air systems the Poseidon must be certified by the Military Aviation Authority (MAA) before entering front line service. This certification activity is a process to demonstrate independently that the aircraft design complies with defined reference standards and can achieve an acceptable level of safety.

The certification process is an extremely extensive one that involves considerable interaction between the Type Airworthiness Authority (TAA), who is the senior engineer in the DE&S Delivery Team, and the Certification Division of the MAA. The process culminates in the issue of a Military Type Certificate (MTC) by the MAA and is detailed in RA 5810. This requirement for independent certification of new air systems by the MAA was a recommendation of the 2009 Haddon-Cave Report that led to the founding of the MAA.

A major element of the MAA 5 year strategy is engagement with other nation’s military aviation regulators.This includes a formal process of recognition and, where appropriate, harmonising our approach internationally. Poseidon was introduced into US Navy service under the auspices of their procurement organisation Naval Air Systems Command, known as NAVAIR. The aircraft certification process was carried out by the US Navy’s airworthiness regulator, the 4.0P division of NAVAIR. As part of the MAA’s mutual recognition programme, NAVAIR 4.0P were recognised in October 2014 as a regulator whose approach to airworthiness, certification and regulation are acceptable to the MAA. Once the decision to procure Poseidon was confirmed, it was decided that it would be logical to exploit the mutual recognition process and use NAVAIR 4.0P’s work on Poseidon as a key building block of the MAA’s certification of the aircraft.

Whilst NAVAIR 4.0P has been recognised by the MAA, as with any other military regulator, it is important to note that there are significant differences in their regulatory approach. These mean that exploiting their certification activity was not simply a matter of “rubber-stamping” the NAVAIR equivalent of a MTC. Rather the MAA has developed a structured approach to re-use existing certification evidence to cater for differences in UK regulations, together with any differences in the configuration and operation of the aircraft in RAF service compared with the US Navy. This approach is explained in greater detail in 2 MAA Regulatory Notices, MAA/RN/2016/11and MAA/RN/2015/08, and the MAA decided that certification of Poseidon was a suitable opportunity to test its’ application.

The first step in the process is what is termed a Part A Review. This is essentially a feasibility study to carry out an assessment of the acceptability and applicability of the original certification activities, in this case by NAVAIR4.0P. The review also takes into account how the aircraft will be used in service by the RAF and the impact of any configuration differences between the UK and US Navy variants of Poseidon. During the Part A review it was confirmed that the Poseidon had been certified by NAVAIR to the processes that had been reviewed by the MAA during the recognition activity in 2014. However, it should be noted that many military airworthiness regulators have, like the MAA, been created in their current form only in the last decade and have evolved practice from there. Therefore, exploiting the mutual recognition route would probably not be feasible if the UK purchases an aircraft that has already been in service for a lengthy period, as it would have likely been certified to a different process to the one that has been recognised.

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  1. MRA4 was probably the worst and most expensive aerospace project that the UK has ever conceived.

    No matter how much money we spent the MRA4 to fix it’s catalogue of faults would never been a safe aircraft to fly.

      • I think they will have little choice but to procure P8 if they wish to retain that capability. The cost of developing a Airbus 320 MPA is prohibitive.

        My only fear is we will some how end up paying for it as part of brexit deal.

        • Hi Mike
          “MRA4 was probably the worst and most expensive aerospace project that the UK has ever conceived”.
          Well, there’s certainly a lot of competition for that accolade! (Worth a thread in its own!)
          But certainly, the people engaged on the project thought otherwise …… see evidence on-line from one of the MoD’s own specialists on the aircraft, Dr Sue Robertson, to the Defence Committee in 2011.
          Anecdotally, also – on a forum, I did have correspondence with a retired RAF pilot, with contacts in the MRA4 world, who stated that the aircraft was performing well at the time of cancellation.
          Certainly, the project wasn’t managed well, and the decision to retain the old fuselage had disastrous consequences in terms of build complexity and cost.
          But in typical Brit fashion, just when we got the thing working – we cancelled it!
          I believe cancellation had little to do with the merits of the aircraft, and more with the political agenda of an incoming coalition government, keen to rubbish the record of the previous incumbents. SDSR 2010, including cancellation of MRA4, and the subsequent closure of RAF Kinloss, certainly delivered “headline” short-term financial savings – but arguably at great strategic cost.

  2. Evening gents
    Nimrod legacy platform very sound, did what was asked of it. When the requirements were written for the replacement nothing was writing there stating that reusing the old one was the best option, however HMG compromised military capability for the defence industrial complex requirement. To sustain a defence industry they need to be building things.
    This happened with Tornado as well. An aircraft specifically designed to fly at low level and then, for defence industrial reasons turned into a high level point interceptor.
    What we sometimes lack is imagination and confidence, the ability to think outside the box (turning a 737 commercial narrow body into anti anti submarine platform) and the courage of industry to design things before HMG puts money forward.
    They should have thought A320 MPA before they thought, hang on – it’s easier and more profitable to modify something we have already got.

    • GEC Marconi bid a new P3 airframe from Lockheed Martin with a GEC mission system. This would have been in service years ago, but it wasn’t a jet and BAe had plenty of political clout.

      • Indeed, we only have to look at Nimrod AEW Mk3 to realise the power certain companies had over HMG. Fortunately that has all changed now………..

      • BAESYSTEMS had only just been formed and needed to prove itself as a tier one integrator. It went in with the RAF’s Nimrod airframes and discovered they were all different. They took a big hit on this, nearly went broke and the rest is history.

        In terms of systems integration the project was a great success, accomplishing in 4 or 5 years what Eurofighter took 20 to do. Had the MoD stumped up more money for a new platform (the Airbus for instance) we’d have had a highly capable and exportable aircraft.

        As ever British short-termism. We pinch pennies where we should be spending pounds to the long term detriment of our industry and armed forces.

        Really BAE and the MoD should have stopped the project the moment the news about the airframes came to light. The systems integration could have continued while a superior platform was determined. Hindsight is a wonderful thing.

  3. The MAA are a colossal waste of time and money. I’m pretty sure the Americans knew what they were doing when they brought it into Service, and Boeing I’ve heard on the grapevine are pretty handy at building planes.
    Just more layers of nonsense, pointless bureaucracy slowing us down and costing us money.

  4. I really like the P8 but can’t believe it will take 10yrs for us to acquire just 9 aircraft…… and if the F-35 rumours are true, will we really get all 9?

    This government’s attitude toward defence is pathetic really when you think about it.

      • F-35 – reduce what? A mythical figure of 138.
        Remember Typhoon – 232 was the original requirement.
        T-26 – we will get 8, politics will see to that, the commitment has been made and votes are st stake. However, like the T45 at least one will always be along side.
        9 is not enough
        1 a/c SAR
        1 on CAP (which means 5 aircraft, just look at Sentinel)
        1 in maintenance
        2 left for training
        Doesn’t sound like enough to me

        • Hi Lee

          Hope you’re right on the T26’s. Type 45 was also reduced from 12 to 8 then 6 so will be excellent if the RN gets 8.

          I’d go further with Typhoon, I remember reading the original requirement was for 250!! Unthinkable now.

          The MRA4 was for 21, then 18, then “around 12” then 9 so that is why I suggested 9 was minimum as that number has been chosen for the P8.
          Happy to be corrected though.

          • Daniele/Lee – I think we are all agreed 9 P8s are not going to cut it. Too long to bring into service and on top of that, the MOD is looking at adding to it the role of Sentinel ie, overland.

            More demanded again from too few aircraft – some things never change in British defence procurement!

          • Hi Daniele
            The Typhoon number was always to get it over the political “line”, it was never going to be fulfilled.
            9 is the compromise number, the minimum number that could cover:
            GIUK gap
            They will only be able to deploy if one of the above are reduced or not required.
            If you look at the Norway purchase (5a/c) that gives you an idea of how many aircraft are required just to do GIUK patrols.
            15 a/c with at least 20 CR crews would be a good compromise and that would allow Sentinel to be retired. P-8 radar could be upgraded to do overland (Searchwater on the Sea King ASaC Mk.7 shows it can be done), it will not fully replace the capability that Sentinel offers but will better balance aircraft availability against requirements

  5. There are a number of issues with the P8. The primary one is that we, as in the RAF, cannot use our Voyagers, A400Ms or C130s to carry out air to air refuelling. This requires the boom style of refuelling and we only have the drogue style. This will significantly curtail its mission duration and range. I agree 9 will not be enough, will it be enough to maintain protection for the Nukes as well as all the other tasks that are unfolding?
    This is a very expensive aircraft, which doesn’t take long to build. However the system integration and testing now that’s a different matter. Perhaps, what is needed is as per the Navy’s Type 26/31 mix. A high end sub-hunter as well as a cheaper alternative, that can patrol the coastal waters and support other tasks with additional role kit.

  6. Hopefully, we will see another 3 added to the order in due course, especially if we intend the airframe to replace sentinel too with a bolt on system.

    The latest thinking however seems to be centered around replacing the Sentinel and AWACS with a biz jet sized platform that can do both jobs.

    As for the MR4A, well, it quite simply should never have progressed past the early stages, as the severe engineering problems mounted and the required numbers dropped.

    If all 9 had made it into service, we would be looking at a further huge upgrade and modification cost by 2025.

    Just look at the huge cost of Merlin upgrade, for an example of the utter folly of a small bespoke fleet.

    The aircraft would have been a very expensive nightmare to own and maintain in service in these cash strapped times.


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