Evidence submitted to the Defence Select Committee argues that seven additional P-8 Poseidon aircraft should be acquired, bringing the total fleet to 16 aircraft.

Written evidence submitted by Air Vice-Marshal Andrew L Roberts (Retd) states that:

“SDSR 15 proposed that nine P-8 Poseidon MPA be acquired. At the time, the P-8 was the only MPA on the market capable of meeting the UK’s needs in a reasonable timescale.  Given the urgency of filling this acknowledged gap in the Defence Programme, the Government was undoubtedly justified in selecting that aircraft without going out to competition.

However, capable though the P-8 may be, the number of aircraft planned is undoubtedly inadequate to fulfil even the highest priority tasks likely to be assigned to the force in tension and hostilities.”

The ten primary tasks for which MPA are likely to be required in peacetime, tension and hostilities are, according to the submission:

    1. Protection of the UK’s national strategic deterrent.
    1. Protection of naval forces – in particular, the new aircraft carriers.
    1. Protection against threats to commercial and other shipping, including counter-piracy.
    1. Surveillance of, and action against, threats to trans-continental under-sea communications cables.
    1. Protection of the UK EEZ (including oil rigs and shore facilities) against potential threats, assistance in counter-terrorism operations and, possibly, fishery protection post BREXIT.
    1. Protection of overseas territories, including the Falklands.
    1. Operations in such areas as the Caribbean in support of counter drug-running operations.
    1. Support to Special Forces.
    1. Gathering electronic, acoustic and photographic intelligence.
    1. Fulfilling the UK’s international obligations for Search and Rescue in aid of shipping and aircraft in distress out to longitude 30 degrees west, in accordance with the International Convention on Maritime Search and Rescue, 1979.

Table 1 below shows the operational coverage which was possible with the original Nimrod MR2 force of 21 aircraft and compares this with that possible with nine P-8 Poseidon MPA. The table also shows what established fleets of 12 or 15 P-8s could achieve.

 21 NimrodMR2

No of sustained

ASW patrols

9 P-8

No of sustained

ASW patrols

12 P-8

No of sustained ASW patrols

15 P-8

No of sustained

ASW patrols

40084 [2]6 [3]7 [4]
60074 [2]5 [2]6 [3]
80063 [1]4 [2]5 [3]
90053 [1]4 [2]5 [3]
1,00043 [1]4 [2]4 [2]
1,10042 [1]3 [1]4 [2]
1,2003*2 [1]3 [1]4 [2]
1,3002*2 [1]3 [1]3 [2]
1,4002*1 [1]2 [0]3 [2]


The submission also argues that in terms of sensors and weapons, the overall capability of the P-8, as an MPA, is not dissimilar to that of the Nimrod MRA4, both representing a very considerable increase in ASW capability over the Nimrod MR2.

However, the maximum flight time of the P-8 is only about 10 hours, allowing it to remain on station for slightly less than five hours at 1,000 nm from base. Although the P-8 is fitted with an air-to-air refuelling system, this is incompatible with the probe-and-drogue system used in the UK’s A330 Voyager tankers.

The conclusions made are;

  • The planned force of only nine P-8 Poseidon aircraft would be insufficient to guarantee concurrent continuous cover for both the UK deterrent and other vital tasks, including CVA protection, in tension and hostilities.
  • To remedy this situation, seven additional P-8s should be acquired, bringing the total fleet to 16 aircraft, noting that any additional aircraft would need to be ordered before Q2, 2019.
  • Flying booms should be fitted to the RAF’s A330 Voyager tankers.
  • Consideration should be given to establishing aircrew above the planned 2:1 crew-to-aircraft ratio, if necessary by making use of Reserve/Auxiliary aircrew.
  • Were the P-8 force’s responsibilities to be extended to include responsibility for overland surveillance, additional P-8s should be acquired as necessary.
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George has a degree in Cyber Security from Glasgow Caledonian University and has a keen interest in naval and cyber security matters and has appeared on national radio and television to discuss current events. George is on Twitter at @geoallison
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Nath (@guest_424614)
5 years ago

Reality bites.

Lee1 (@guest_424615)
5 years ago

Can the refuelling system on the p8 be retrofitted with a probe?

Maybe however it would be better to have the voyagers fitted with booms as this would give greater flexibility in both aircraft we can buy and also potentially allow the new Tempest designers to use the system best suited to its design.

Daniele Mandelli
Daniele Mandelli (@guest_424619)
5 years ago

Two thoughts.

1) What do we choose to cut to pay for extra.

2) Is the capability better than nothing, and we accept the limitation, depending oh what we might lose to increase it.

Julian (@guest_424630)
5 years ago

On (2), am I victim to failing memory or bad media reporting or do I remember some instances where we’ve had to ask other nations (Norway?) for maritime patrol aircraft when we’ve needed to do a specific search operation as opposed to general patrolling? At least having our own capability would avoid the potential embarrassment of that, or the more significant issue of other nations not being able to release suitable assets at short notice when needed.

Daniele Mandelli
Daniele Mandelli (@guest_424650)
5 years ago
Reply to  Julian

No you remember correctly Julian, unless my brains gone too! I recall France Norway and USN involved in a hunt for a suspected Russian SSN.

John Clark
John Clark (@guest_424621)
5 years ago

I would suggest an initial modest increase to 12 airframes, with the maritime (8) version of Protector to back them up.

If no UAV is procured for the support roll, then a further 4
P8’s will be needed down the road.

If the RAF have to make do with 9, then its small fleet will be very hard worked indeed!

Bloke down the pub
Bloke down the pub (@guest_424624)
5 years ago

Maybe the government are waiting to see if the Airlander will fill the gap.

David Steeper
David Steeper (@guest_424625)
5 years ago

Demote all Wing Commanders to Sqd leaders and all sqd leaders to flight commanders. Money found !

Steve M
Steve M (@guest_424628)
5 years ago
Reply to  David Steeper

I guess all we can do is wait for the fighting to be over and the MDR published. Then we know where UK Defence stands.

Steve Salt
Steve Salt (@guest_424629)
5 years ago
Reply to  David Steeper

What service has the rank of flight commander ?

Evan P
Evan P (@guest_424644)
5 years ago
Reply to  Steve Salt

If you’re talking about the RAF then it’s Sqn Ldr down to Flt Lt.

David E Flandry
David E Flandry (@guest_425131)
5 years ago
Reply to  Steve Salt

The RAF has Wing Commander, equivalent to RN Commander or Army Lt. Colonel. Flight Lieutenant is equivalent to RN Lieutenant or Army Captain.

John Clark
John Clark (@guest_424632)
5 years ago

It’s interesting, I assume that the figure of 9 was derived from the 9 MR4’S that BAE Systems was due to deliver prior to cancellation.

If that’s the case, then it was based on a threat situation dating from 07- 09, so well out of date now.

Liam (@guest_424633)
5 years ago

Acquisition of Triton would help perhaps?

John Clark
John Clark (@guest_424637)
5 years ago
Reply to  Liam

The Maritime version of Protector would be a better fit for us Liam, plus it was have the obvious benefits of commonality with our Protector fleet.

Mike Saul
Mike Saul (@guest_424643)
5 years ago

The P8 is a great flexible asset, given our defence responsibilities and commitments it would not be unreasonable to order 18 aircraft, but then again where the money going to from?

jeff bochenzki
jeff bochenzki (@guest_424652)
5 years ago

why not get a CASA Eads c-295 mpa ??

Mr Bell
Mr Bell (@guest_424657)
5 years ago

They should go for an additional 6 aircraft. Retrofit the entire fleet with a flying probe to allow AAR. Cost will be what £1.4-2 billion. Well worth it for the sustained capability offered and resilience.
Although would you opt for 6 more Poseidon or 2 more type 26s? I would go type 26. Or another view 1 more astute class? Limited money dictates difficult decision if any uptick in defence budget is forthcoming. In reality we need to get to 3% GDP to defence ratio to get the numbers of platforms and force size/ manpower needed.

Daniele Mandelli
Daniele Mandelli (@guest_424750)
5 years ago
Reply to  Mr Bell

Extra 2 T26, 1 Astute, or 6 P8. I choose the P8.

ngatimozart (@guest_424941)
5 years ago

Well if they want to acquire some more, then they had better be real quick, because word has that last orders have been called. Having said that, they might be better to acquire the MQ-4C Triton to go with the P-8A. The Triton can be accessed and controlled from a P-8A and it has approximately 33 hours duration.

David (@guest_425480)
5 years ago

Never going to happen. It’s taking 10yrs to get 9 aircraft as it is. When they enter service, they will be worked into the ground!

5 years ago

[…] year, evidence submitted to the Defence Select Committee argued that seven additional P-8 Poseidon aircraft should be acquired, bringing the […]

Paul42 (@guest_484690)
4 years ago

The key thing to remember here is that the funding to purchase more aircraft is available, indeed we could actually spend a lot more on Defence if we chose to. But therin lies the problem…….UK governments that are completely blind to reality and not to spend/waste Billions elsewhere.