Future Maritime Patrol – Part 2 (Dedicated Long Range Aircraft – P-8A Poseidon)

P-8A Poseidon

Future maritime patrol my well require a dedicated long range aircraft like the Boeing Poseidon P-8A Multi Mission Aircraft

(by the way, sorry for the auto start video below)

To the sweetshop, poste haste!

In the previous post I had a look at background, the wider context and a brief look at the missions.

Missions influence equipment requirements, for example, if the SAR and EEZ security mission is discounted the requirements change dramatically. If we want to do deep water at range ASW then a system with short range is going to be money wasted, no matter how cheap it.

I also commented on what I see as an important capability gap but one that must take its place in a priority list

Because the world has moved on significantly since the withdrawal of MR2 and with the long MRA4 shaped shadow still in place, the arguments for immediate reinstatement in SDSR 2015 are not so completely compelling that such a programme would find itself automatically at the top of the shopping list.

In short, a like for like Nimrod replacement is going to be a tough sell and not the automatic shoe in many people think.

On balance, I think SDSR 2015 will seek to close the maritime patrol capability gap but with what, who can predict?

As I have also mentioned in previous posts on this subject, what is so fascinating is trying to see how the obtaining of one piece of equipment can have a number secondary capability, force composition and cost effects.

In fact, I would go further with this and state that these secondary effects should be fundamental to equipment selection. The days of narrowly focussed requirements and single mission equipment are over

The British Armed Forces cannot afford one trick ponies and maximum utility must be squeezed from every single element.

We all know the options on the table but in this post I am going to explore these connecting ‘capability strings’.

Along with Fightiness, that is another Think Defence(ism)

We also all know (Think Defence readers being an intelligent bunch) that the sticker price of equipment a or b is not where the real cost lies, especially for large and expensive pieces of equipment like aircraft. Creating and maintaining a training pipeline, realistic training, spares and maintenance and a myriad of other hidden costs are what the MoD (rightly) scrutinises in great deal in the acquisition process.

Maximising commonality as a means of cost reduction is a drum I have been beating since I started Think Defence, we don’t do it enough and need to do it more. This consideration will also feature heavily.

That said, let’s have a quick look at the contenders first, in this part, a dedicated long range maritime patrol aircraft

A Dedicated Long Range Maritime Patrol Aircraft

Boeing P8

The advantages should really be obvious.

How about a Hollywood video for starters, featuring the worlds dumbest submarine captain

It is there, on the shelf, ready and waiting for a purchase order.

Over the lifetime of the aircraft the UK could participate in and take advantage of its continual development in a global fleet, driving costs down as that nice man Uncle Sam will pay for most of it.

The Seedcorn personnel are currently involved with the P8 programme and could easily transfer into training and development roles for a UK P8 fleet.

However, the UK armed forces do not operate any 737 derived aircraft, it would require a completely new training and support infrastructure although how much of that could be obtained through resource sharing with India, the USA and Australia or delivered through a contractor led arrangement would have to be explored.

No one else in Europe is likely to buy it (although you never know) so interoperability who whom and where and when becomes an obvious question, given the Pacific Pivot and mostly non UK sphere of operations for the current buyers.

The US and Australians have also bought into a particular concept of operations, the Indians, seemingly another and the UK would have to make a similar decision.

Much has been written about the move to higher altitude ASW with the P8, some say it is a sensible development given the changing nature of the threat and will deliver a range of benefits, others say that it is a direct result of the compromises caused by the airframe and its inability (or at least reduced performance) to operate in the same way as say a P3 or Nimrod might i.e. lots of turning, altitude changing and low level flight.

I suspect the answer lies somewhere in the middle.

Whatever the reasons, the Increment 2 of the USN P8-A will introduce the high altitude ASW capability that might include wing kits for the US Mk 54 torpedo and even a MAD UAV, the current occupant of that drawing board being something called the MAG Eagle Compressed Carriage (MECC), a variant of the Boeing Dominator UAV itself a variant of the Scan Eagle Compressed Carriage (SECC) design.

Neat eh, I actually quite like the whole concept of air launched unmanned systems like the SECC/MECC/Dominator but the problem is this.

Unless you have somewhere for them to land, they have to be expended (or thrown away)

The Scan Eagle does have a low footprint landing system, the Sky Hook, that can be fitted to even small vessels, but if the P8 is operating far from land or allied shipping, the UAV is going in to the water.

Unless of course, the unmanned aerial refuelling system in the video below is used

Only joking, we would have to negotiate with Air Tanker :)

So what about torpedoes and sonobuoys?

Lockheed and Raytheon have both come up a solution to the medium/high altitude delivery of a lightweight torpedo. The Lockheed Martin Longshot High Altitude ASW Weapons Concept (HAAWC) uses a wing kit and GPS system to deliver and drop the torpedo from high altitude, releasing the torpedo from a the wing kit at a couple of hundred feet or less.

Defense Industry Daily has a nice write up on the Lockheed Martin system, click here

The Raytheon system is called the Fish Hawk and it has been reported that the Indian MoD prefers this to the Lockheed Martin system.

Rayhtheon Fish Hawk
Rayhtheon Fish Hawk

These high altitude stand-off delivery systems have also been proposed for sonobuoy deployment but the initial releases will use conventional tube launched methods used instead, the P-8A uses a system from Excelis for example.

The MRA4 would have used the Active Search Sonobuoy System (ASSS), to meet the Air Staff Requirement 903 but with the withdrawal of MR2 and the cancellation of MRA4 it is not clear whether any were retained.

The package that Ultra is bidding for ASSS includes the company’s new Active Low Frequency Electro-Acoustic source (ALFEA); a version of the SSQ-110 impulsive source – of which USSI is one of two manufacturers – adapted for carriage by the Nimrod; the SSQ-955 High Instantaneous Dynamic Range (HIDAR) receiver buoy with an integral GPS receiver; and the SSQ-981 version of the Barra receiver buoy with a modified horizontal planar array.

The A-size ALFEA buoy, which operates in the 1-2kHz frequency range, exploits technology from Ultra’s family of sonar countermeasures devices. It incorporates a GPS receiver and can generate a large number of pings (reportedly several hundred) with programmable waveforms. Ultra says that recent tests in Lake Seneca, New York State, “have shown that it can comfortably meet the designed source levels”.

ALFEA incorporates a 99-channel Autonomous Function Selection (AFS) facility, together with a UHF command function to control its operation following deployment. The latter is compatible with those used for the UK SSQ-963 CAMBS (Command Active MultiBeam Sonobuoy) and US AN/SSQ-62 DICASS (Directional Command-Activated Sonobuoy System).

Ultra Sonar have now incoporated these into their Ultra Multi-Static Active System (MSA) that splits the transmitter and multiple receivers.

The Ultra Multi-Static Active System (MSA) comprises a field of transmit and receive sonobuoys and the necessary processing to detect and track targets without overloading the operator. The system uses combinations of the following buoy types, all of which are available from Ultra with embedded GPS for precision operation:

  • SSQ 926 ALFEA Electro-Acoustic Source
  • SSQ 955 HIDAR High Dynamic Range DIFAR
  • SSQ 981E Barra (Horizontal Planar Array)

Trials of this have confirmed their effectiveness against small and low acoustic signature submarines in cluttered environments, tests being completed in the English Channel.

The point of all this?

The P8-A won’t be getting the MSA but one called the Multi static Active Coherent (MAC) system, and then, if all goes to plan, this year in something called Increment 2. Increment 2 also includes Automatic Identification System integration and rather unbelievably for a new aircraft, a new computing architecture, maybe that is the norm with incremental development. The IOC for Increment 2 is now planned for 2016.

The high altitude ASW weapon won’t be available until Increment 3, the full scope, budget and requirements yet be defined or agreed but reportedly aiming at a 2020 timeframe.

Which brings us neatly onto torpedoes.

The US Navy, Australia, and possibly India, use the Raytheon Mk 54 Lightweight Torpedo, the UK does not.

Instead we have the BAE Stingray Mod 1

If we want to join the high altitude weapons release party then we would need to consider the options.

Both the Mk54 and Stingray have very similar physical attributes but if we want to use the Longshot or the Fish Hawk wing kits then that would be extra integration. Other options would include obtaining a small quantity of Mk 54’s exclusively for use with the P8 or withdrawing the Stingray completely from Merlin and surface vessels in favour of a single common fleet of Mk 54’s, none of which would be ideal from a cost, logistics or industrial perspective.

If we chose not to implement Increment 3 then any UK concept of operations would include likely release of weapons at low altitude, with all the fatigue and potential operational compromise that might entail.

The US Navy decided to eliminate the MAD boom from the aircraft in order to save weight, hence the stand-off solutions, the Indians on the other hand, said nothanks to all that, can we have the MAD boom please. The logical conclusion is the Indian MoD accepted some performance penalty.

The Bollywood version

There is another downside to the P8, airborne refuelling

Although the P8 is hardly a ‘short’ range aircraft it is derived from a 737, a medium range civilian airliner. Neither the Indian, Australian or US Navy variant is fitted with a refuelling probe. All three have a boom receptacle which might not sound like a big deal but in the context of the UK’s airborne refuelling fleet is a bit of a show stopper.

The choice is simple, enter into a development programme with Boeing to develop and fit a refuelling probe, modify the Voyager refuelling aircraft so they are fitted with a refuelling boom, assume/hope that someone else with the right tankers will be available or simply accept that a UK P8 will not be refuelling in the air for most of the time and 4 hours at 1,200nm is the limit of performance (I think we know which one it will be)

Endurance and range are factored into the numbers needed for a given requirement and the lack of a UK only operation refuelling capability could well push the final numbers needed up.

Am always very wary of quoting figures because there are so many variables but it looks like a unit price of between $180m and $200m is about the going rate, don’t expect much change from £150m each.

The P8 uses the same basic CFM56 engine as the RAF E3 and Airseeker aircraft so there would be some measure of commonality, the specific engine variants might be dissimilar though.

If the sensors on the P8 could be developed further (and this is certainly on the development plan) it could replace the Bombardier Challenger based Sentinel R1 although endurance and altitude limitations might force compromises in capability. The main search radar is the Raytheon APY-10 radar which although advanced is not a replacement for the ASTOR system on the Sentinel.

An additional sensor might be fitted to a UK P8, or the R1 systems transferred.

Both options add weight, cost and complexity

I think much of the logistics support for Sentinel is delivered through the Raytheon the training commonality derived savings would be worthwhile. The implications on the ground element of Sentinel/ASTOR would also need to be considered.

The US seem to be indulging in a spot of inter service argy bargy with the US Navy looking at something called the Raytheon Advanced Aerial Sensor (AAS) that would sit in a 12m long ventral pod and the US Air Force promoting the idea of a small to medium sized business jet such as the Global Express, amusingly enough.

From a Raytheon press release in 2009

The U.S. Navy has awarded a multi-year contract authorizing Raytheon Company (NYSE: RTN) to begin development of the Advanced Airborne Sensor, the follow-on to the Littoral Surveillance Radar System (LSRS).

The AAS program will equip the P-8A Poseidon, the Navy’s next patrol maritime aircraft. LSRS is currently operational on Navy P-3C Orions; the AAS will provide airborne radar surveillance with next-generation line-of-site capability.

Awareness and action are critical not only to today’s mission, but the ever changing threats of tomorrow. “We will be ready with intelligent technology when the Poseidon takes its place as the Navy’s ISR capability in the fleet,” said Capt. Scott Anderson, LSRS and AAS program manager.

As the sensor prime contractor, Raytheon will oversee the mission systems integration, consisting of the development, production and installation of the AAS on the Poseidon. Raytheon will work closely with its associate prime contractor, Boeing, for engineering, aircraft modifications, integration and flight test.

“This is a major leap in technology in support of our customer’s missions,” said Tim Carey, vice president for Intelligence, Surveillance and Reconnaissance Systems. “As the demand for Intelligence, Surveillance and Reconnaissance systems increases, we are proud to provide our customers with ISR capabilities that are recognized around the world.”

By maximizing the incorporation of Commercial Off-The-Shelf (COTS) technologies, the AAS will be highly supportable, maintainable, scalable and upgradeable, reducing unit production and life cycle costs.

Raytheon also provides continuing mission support of Navy operations, logistics and sustaining engineering of LSRS through a previously awarded multi-year performance-based contract.

AAS was always designed for fitting on the P-8A, the bomb bay is at the rear of the aircraft specifically so the long radar pod can be fitted to the centreline pylons without impeding it. A follow on version of the  APS-149 Littoral Surveillance Radar System, the AAS remains difficult to find information about, but it is said to have a very good performance. Comparing it to the ASTOR system on the RAF’s Sentinel R1’s on here would be silly, the people who really know the difference will be keeping a very tight lip but I think we would be on safe ground to say that it is somewhere in the same ball park.

ANDERSEN AIR FORCE BASE, Guam – An P-3 Orion participating in the Valiant Shield 2010 exercise taxi on the Andersen flightline, here Sep. 16.  The aircraft is a key component of the major joint flying exercise that kicked off this week. (U.S. Air Force photo by Airman 1st Class Jeffrey Schultze)
P-3 Orion with LSRS

The US Navy seems pretty bullish and have issued contracts for integration work on AAS, it is happening.

The latest on the USAF position on an E-8 JSTARS replacement can be found here

In a nutshell, the report says the USAF number four priority (after F35, KC-46 tanker and long range bomber) is a replacement for E-8C. A cynic might say sitting underneath the F35, KC-46 and long range bomber programmes means in reality it is way down the list when it comes to money and I would tend to agree. It seems ridiculous that the US Navy has already stumped up the cash and will have a working solution in service. I know US inter service politics can get ridiculous but surely the DoD will knock heads together and impose some sanity, especially in the coming times of austerity.

Meanwhile, the UK could sit back and watch who and what comes out of the mix.

If we assume that the Advanced Airborne Sensor is as least capable as ASTOR and the R1 Sentinel there exists an opportunity to delete an entire fleet of aircraft to maximise commonality and improve utilisation of a P8 multi mission aircraft. As I described in the first part of this series, the at range deep ocean ASW mission sits in the less likely but high impact quadrant whilst the general overland ISTAR mission, of which the AAS would deliver in spades against, is in the lower impact but much greater likelihood of use.

This raises an interesting question about single role v multi role and the ability to sweat ones assets by using the same aircraft (perhaps slightly expanded) fleet for both ASW and ISTAR missions, thus lowering to total operating costs.

It is not a zero cost option, we would have to buy AAS, completely change the training and operating modes, investigate changes required to ground equipment and determine whether our existing analysis and dissemination architecture could cope. A detailed performance comparison would also be needed.

If this complex analysis says yes, it is viable and worthwhile to use the P8 for both it means we have a small fleet of nearly new Global Express airframes to now find a home for.

A few options spring to mind (besides flogging them);


Re convert them to business jet configuration and use them for the communications and VIP transport role currently being carried out by No 32 (The Royal) Squadron with six HS125‘s and two BAE146‘s

Politically, buying new executive jets is always going to be a tough sell, providing the capability by converting second hand airframes all of a sudden looks rather more palatable, especially if you roll an aeromedical transfer capability into the mix.

Personally, I don’t think there is anything wrong with the nations head of state, prime minister and senior military personnel on ‘company business’ travelling by private jet. One that can also provide aeromedical evacuation or transfers for personnel on compassionate grounds signals a strong commitment to personnel welfare and wellbeing; ‘if you are injured, ill or need to get back home sharpish, the nation will get you there as fast as it can.

I am not talking about gold taps and hot and cold running floozies here, just a modern and understated interior that the Sun could not run an exclusive one.

Global Express Interior
Global Express Interior

Afghanistan has shown the benefit of having a Role 3 capability in theatre but this will not always be the case. The current C17 and future Voyager aircraft provide aeromedical evacuation cover with 4626 (County of Wiltshire) Aeromedical Squadron and the Tactical Medical Wing.

A Sentinel conversion would provide another option.

aeromedical evacuation
aeromedical evacuation

In this option, we could replace the current BAE 146 and HS125 fleets with a single fleet. I don’t know whether the current short field performance or Royal cabin suite of the BAE 146 or the seating arrangement in the HS125’s could be replicated across a converted Sentinel fleet. I can’t make a judgement about how expensive it would be to reconvert given the fairly extensive Sentinel airframe modifications but it should be included in the list.


Remove the heavy radar systems and insert a Goodrich DB-110 sensor system in its place. I understand there was provision made for the sensor in the original design but it was removed on cost and weight saving grounds.

The DB-110 is the same as used on the Tornado RAPTOR pod, a highly useful capability but with the impending out of service milestone rapidly approaching for Tornado this could be a reasonable way of retaining some capability.


In stripping down to the bare essentials the weight induced performance reductions could be reversed turning the Sentinel aircraft back into the high altitude, huge range racing snakes they once were. Leave the satellite communications systems in place and there you have a very high responsiveness, high speed, ultra long range imaging platform that can instantly send its product back to the UK, unlike a RAPTOR equipped Tornado.

Shades of Canberra PR.9 anyone?


Remove the heavy radar systems and insert two or three EO turrets.

Add in a communications relay and you have a long endurance communications relay/translation system with the added bonus of persistent ISR.

A cross between the Global Express based, Raytheon Battlefield Airborne Communications Node and Northrop Grumman Firebird

The BACN equipped Global Express has proven to be a vital yet relatively low profile capability in Afghanistan.

I also like the option of combining option 2 and 3.

Ordinarily, the aircraft would be configured as Option 1, that being a high speed ultra long range DB-110 platform that could rapidly respond to emerging situations and provide high quality imagery via a satellite link reachback.

If the situation demanded, there was more of a sustained presence required and ultra long range less of a requirement because basing facilities closer to or in theatre were available then you could just roll the BACN electronics and operator consoles onboard and fly the persistent airborne communications and imagery node mission.

What’s not to like about that?


Let’s be clear, the Boeing P-8A/I Poseidon is the real deal, or more accurately, will be the real deal.

We should be in no doubt that despite the recent wobbles and adverse press the US DoD will make it work and their confidence can be seen in an equally recent authorisation for full rate production.

For once, the MoD won’t be on the hook for last minute development costs as we can purchase a mature(ish) system with some growth potential in a couple of years.

That growth potential will still, self-evidently, need additional funding and decision on wider equipment fleets (torpedo/sonobuoy/UAV) especially if we adopt the high altitude concept of operations.

Airborne refuelling would remain a costly problem, or not, if we accept its not a problem after all.

It is not a simple off the shelf system and will impact a number of other programmes.

It is not likely to meet all UK requirements (AAR for example)

It is not yet the finished article with a number of kinks to iron out and incremental development milestones to complete.

It is not cheap either, in fact, we might reasonably argue that it is the current gold standard with an equally gold standard price tag.

It is however, as close as we are ever going to get to a genuine Nimrod replacement and we are not on the UK for any basic system development.

Can the UK afford it, I think the answer is probably yes, but, how many and what other spending priorities it would displace would be down to something akin to this!

If we purchase a small fleet, perhaps 6 to 8 airframes, there is potential to offset some of that cost by utilising the fleet for the existing Sentinel R1 role in the longer term. Bringing a UK P8 into service in the early 2020’s, following an SDSR 2015 period order and providing Boeing can deliver, allows the aircraft systems and AAS to mature to the point of readiness for service.

We could extend R1 Sentinel for 5-8 years as the transition from R1 to P8 AAS completes we would then have a fleet of Global Express airframes to utilise. Apart from simply disposing, there are some interesting capability options that could add significantly to UK capabilities.

I especially like the combination of Option 2 and 3, providing an ultra long range recce platform that can send imagery back to the UK whilst in flight that could if requirements and situations change, convert to a persistent in theatre communications and imagery node.

So, select the P8 in 2015, plan out a 6-8 year transition period during which 6-8 airframes come into service

AAS replaces ASTOR during the same timeframe and plan for a Sentinel conversion to either the communications fleet role or the ISTAR/Comms Node role as defined by Option 2 and 3.

Shadow and Reaper remain to compliment the modest numbers of P8’s

The main point here is not to get into fantasy fleet sizes, have seen people proposing 12 and 18 P8’s, and to think longer term about airframe and component commonality with the potentially huge through life cost savings on offer.

Longer term, selecting the 737 based P-8A would also provide a ready upgrade path to an E3 and even Airseeker replacement, accepting no SIGINT 737 variant exists and the Australian Wedgetail AWACS uses standard 737’s, not the rebuilt and heavily modified P-8A.

Just got to decide what to cut to pay for it!

Seriously for a minute, a fleet of 6-8 P8’s over the next 10 years with a plan for Sentinel withdrawal and conversion into ‘something else’ is not unachievable if we accept, for example, smaller numbers of F35’s or some other reduction in future capabilities, Type 26 perhaps.

If we consider that a single F35B is going to cost somewhere in the £80-120m ball park, a multi purpose fleet of 6-8 P8’s that we could work into a very high utilisation multi purpose capability, able to replace the Sentinel and free up airframes for either capability improvements (Option 2 and 3) or a future airframe consolidation (Option 1) does not look like that a big price to pay or mountasin to climb

What would you trade?

Next post will be a look at a handful of outsiders, a modernised P3, the Breguet Atlantique and Kawasaki P1 then I will get into the converted business jet, twin turboprop, two tier fleets, unmanned options and even the Sea Hercules/Sea Atlas options before wrapping up

Further Reading

Boeing P-8A Datasheet

Boeing P-8I Datasheet

Littoral Surveillance Radar System – Seapower Magazine Article

Raytheon Battlefield Airborne Communications Node (BACN) Datasheet

The Rest of the Series

Future Maritime Patrol – Part 1 (Challenges and Missions)

Future Maritime Patrol – Part 2 (Dedicated Long Range Aircraft – P-8A Poseidon)

Future Maritime Patrol – Part 3 (Dedicated Long Range Aircraft – P3, P1, ATL, 319)

Future Maritime Patrol – Part 4 (C295 and Comparable Options)

Future Maritime Patrol – Part 5 (Business Jet and Unmanned Options)

Future Maritime Patrol – Part 6 (Sea Atlas and Sea Hercules)

Future Maritime Patrol – Part 7 (Summary)


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