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News story: The UK decides to renew continuous at sea deterrent

Successor SSBN

MPs on all sides have voted by an overwhelming margin, to renew our nuclear deterrent – the ultimate guarantee of our national security.

Defence Secretary Michael Fallon said:

We have voted to protect our nation from the most serious threats we may face in the 2030s, 2040s and 2050s.

The British Parliament has sent a powerful message to our allies that Britain is stepping up its international commitments, not stepping back from them.

We will now get on with building the next generation of nuclear submarines to help keep the nation, and our allies, safe for decades to come.

from Ministry of Defence – Activity on GOV.UK

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57 Responses

  1. Was interested in Fallon’s comment regarding Successor being developed under a new office to deliver on time and on budget “…unlike previous warship programs…”.

    Not seen the official transcript yet so apologies if the from memory quote is slightly inaccurate.

  2. Picking up on some of the points raised by Crispin Blunt MP (Cons.) (A fine former Cavalry officer) during the parliamentary debate on strategic submarine renewal.
    Once we have our ‘Air Wing’ carrier and stealth aircraft operational could there be a case for considering the re-introduction of an air launched nuclear weapon capability to the UK military inventory?

    The US Mod 12 B61 nuclear bomb will be capable of being carried internally and delivered by F-35 (At a $40m additional cost) by 2017
    Is there or should there have been a case for this to be formally proposed as a cheaper ‘nuclear’ alternative to Successor/Trident or perhaps a proposal for a reduction in the number of Successor boats with the offset made up by the offensive capability of aircraft delivered free-fall nuclear bombs?

    On the other hand could there be a future case for an aerial delivered nuclear weapon capability in addition to UK Vanguard/Successor/Trident D5?

  3. The US and UK F-35’s are nuclear capable aircraft (Note: not the export versions by default) however short of a severe conflict it is highly unlikely the UK will restore tactical nuclear weapons on top of CASD.

    Despite claims in the House to the contrary last night, the UK maintains a policy of encouraging nuclear disarmament, makes steps towards it by continuing to reduce its own stockpiles significantly and maintains a deterrent only (CASD).

    The alternatives discussed (the 201213 white paper covers a huge range of options) either don’t supply a fully protected or available deterrent, or are viewed as an escalation of nuclear stockpiling in more aggressive systems.

  4. Experimenting with a different procuremrnt/management method for what is the ultimate single source item seems no bad thing. The last totally successful ship procurements were Vanguard and T23. Everything we’ve done since has been fucked up to a greater or lesser degree. We’ve got some good ships but not at the budgeted numbers, costs and capabilities. Most of all the core expertise inside MoD about how to run such programmes appears to have been lost.

    A sovereign programme office for warship building which can hire a small core of experts and empower them to cut through the project management waffle and box ticking mentality would be no bad thing.

  5. The weird thing about the oft suggested successor submarine delivery authority is that there are actually notable parallels with the Vanguard programme in terms of probability of success.

    That programme came at the end of a sustained period of SSN building just as successor will, it also leveraged most of the lessons from that. The Astute programme may have been a mess over the first 3 boats but the kinks now seem worked out and the cost is falling. If anything the greater risk is in upsetting the apple cart.

  6. “…Successor being developed under a new office to deliver on time and on budget….”

    Didn’t that used to be the ‘Director of Naval Construction’ ?

  7. @Ravenser
    The United Kingdom having lost its airborne nuclear component it would be very expensive to restore.

  8. Barborossa,

    Only for people with no knowledge of history. The DNC was no better at delivering on time and budget than DE&S and MoD are today.

  9. @Ravenser At the moment only the F-35A will be cleared for the B61-12, as part of Block 4 (so 2024-ish). I’d guess it wouldn’t fit the bays of the F-35B.

    Also you run into all sorts of treaty complications – you can’t just go round buying nukes from other countries. NATO can use US B61’s on their aircraft as part of a deal that predates NPT so was grandfathered into it, but if you wanted British nukes then you’d have to design a WE.177 successor.

  10. I’d have thought the most likely tactical nuke delivery method would be TLAM (or equivalent) from our subs.

  11. There was no reason (Hardware wise) for the vote to be now. However,(politically) it makes the new PM look resolute & highlights how hopeless Corbyn is. Plus it sends a message, post Brexit, on how Britain remains a tier 1 NATO nation & a strong ally.
    Re Successor, I hope the gap between Astute & new Trident is not too great, as we do not want to lose skills (again).
    Also, how many tubes will successor have? I thought we were cutting from 16 to 12 tubes, but the Mail thinks its 16 again.
    Hague said the UK would not have more than 225 nukes, max. Treaty limits of 4 warheads per missile. So 4×12=48 warheads per boat x 4 boats= 192. Leaves you with room for 33 tactical nukes if you wanted that capability back.
    I think we should keep an eye on the proposed USAF LRSO new cruise missile for the 2020s. If we bought 33 of those & fitted/adapted the UK Trident warhead, minus the fusion boost, that is rumoured to give you a “clean” 10kt tactical nuke. No money now, this would be a spend for the late 2020s or 2030s.
    You probably don’t want to wipe out a country just because some warlord uses chemical/biological/dirty weapons, nor show where your Trident sub is, by launching just a single missile.

  12. JH – One reason for having the vote now might be so we can get on the institutional and contractual arrangements that we hope are going to support a smooth and trouble free build.

    That’s at least as important as the work timetable for cutting metal.

  13. @Frenchie: the reason why nukes are so hard to develop is purely because we cannot test. Remove that restriction, set up a testing area, and we’d have new nukes in five years.

  14. @Wf,
    With the pooling of our capabilities in simulating nuclear tests, on the Valduc site in Burgundy with the megajoule laser, nothing keeps you from doing all the tests that you want.

  15. @Frenchie: with all respect to our gallant French allies lasers, that’s not testing. It’s simulation with knobs on :-(

  16. I am slightly surprised at the amount of (frankly unrealistic) salivating around the UK re-developing a tactical nuclear capability off the back of this news.

    The US has a long history of books and books of discussion on the need for an escalating range of nuclear options which has kept programs like the B61-12 and the LRSO alive to meet this counter-force slanted theory of nuclear conflict.

    The simple fact is that the UK never had this nature of thinking in our nuclear posture. The purpose of CASD is fundamentally a counter value proposition. If Russia (and it has always been Russia) hits us CASD exists to make Moscow and/or Saint Petersburg uninhabitable. That is the fundamental purpose of the system.

    Our government is also committed to long term multi-lateral disarmament through our commitments in the Treaty on the Non-Proliferation of Nuclear Weapons. The costs alone of a new warhead design would be prohibitive alongside the successor program. It would also be technically unsound given the constraints of the comprehensive test ban treaty. These treaties make acquisition of the B61-12 a fantasy at best. The mere presence of these weapons (which would be limited in number and easily tracked) would make them dangerous in a moment of crisis as any change in their status can be misinterpreted.

    Finally the USAF is also on a major go slow in certifying any F35 for a nuclear role as they don’t want any further F35 spend to endanger money for the new bomber/LRSO. It’s been quietly pushed back several times and i expect that will continue.

    UK tactical nuclear capacity is not coming back.

  17. @PE – no, it was a purely political thing. It was intended as Cameron’s little treat to himself, to reunite the Tories after a Remain vote whilst poking Labour’s festering wounds from the 1970s. The context isn’t quite what he intended but the effect is still the same.

  18. I agree with McCall, nuclear weapons are a strategic level deterrence, the mentality that they can be used for tactical level applications has died out a long, long time ago. With the current anti-nuclear stance worldwide, any country that uses a nuclear weapon in a tactical role is on a quick road to becoming an international pariah and in democratic countries, a sure bet to lose the next election.

    Nuclear weapons have long since been seen as weapons of last resort, one that you use to take your enemy down with you when you no longer have any chance of winning or surviving. Using them “casually” in a tactical role only opens the door to potential total war and escalation of conflict into the WMD level, provokes international condemnation and public outrage. Simply not worth the potential gains to use it even in a “limited” role.

    Because of this, I have severe doubts about the resurgence of any tactical level nuclear weapon capability or development.

  19. @JH
    The START I agreement ( which expired in 2009 with an understanding in place to continue to adhere to it untill further reductions are agreed) limits the signatories US and Russia to 1600 launchers and 6000 warheads each thus the 4 warheads per missile but each Trident D5 can carry from 8 to 12 MIRV but START I does not limit the number of warheads per missile in itself. Also the UK is not a signatory , what we do is voluntary to show our commitment to multilateral nuclear arms reduction ( and saves cash ).

  20. El Sid, the AQ article is pretty sensationalist. While “technically” true that ISIS is an AQ spinoff, *WHY* it spun off is because AQ expelled them for both ideological and operational differences (i.e they were too brutal even for AQ). This cutting off was what sparked the original attack into Fallujah in the first place.

    I kind of feel a certain slant to the article.

  21. The debate on tactical nukes should have moved on. Sure, in the 50s/60s there were thousands of all sorts of tactical nukes. Luckily, people saw the folly of that & the vast bulk have been retired.
    I doubt any serious person would be the first to use a tactical nuke in a conventional war.
    However, there is now this potential situation of warlords/failed states with extremist groups in charge, that may be tempted to use chemical/biological/dirty weapons. How do you deter that? This is the scenario for having a few (thirty odd) tactical nukes.
    I do not see that you need to develop a brand new warhead. The US/UK developed plenty in the past. Just select one of those & modernise/adapt it to your need.
    For the UK, our Trident, minus the fusion boost would probably do the job. Failing that, the UK developed a very compact 6kt warhead for the Bloodhound missile, that was tested, but never deployed.
    The Americans have umpteen variations on the B61, used in bombs & missiles.
    If you have nothing between conventional weapons & a boat load of Trident missiles, then many dictators/extremists, will calculate that we are too nice to wipe them out with 12 Trident missiles,that we are already dropping conventional weapons on them, so they will feel safe to hit Britain with chemical/biological/dirty weapons, knowing we will not hit back with a boatload of Tridents.

  22. Having done my time as an armoured division’s nuclear fireplanner, and being familiar with the yields available for 155mm, 203mm and Lance, and such things as the firing tables which of course include consistency data, I obviously take the view that battlefield nuclear weapons may have their place, depending on the situation (as ever)..

    I actually know what I’m talking about, which I suspect puts me fairly well ahead of most posters here!

  23. Good news. Now come all the usual suggestions that ALCM or free fall bombs are somehow as much of a deterrent as a virtually untraceable boomer.

  24. The UK disposed of its tactical nuclear weapons in 1997 because Tony Blair wanted to throw some red meat to the far left nutters in the Labour party and MoD acquiesced as it saved a bunch of money that could then be spent on other things. The cost wasn’t just in buying the weapons but also in storing them, training to use them and integrating them. They were also generally only useful in very specific circumstances- many of which had vanished by 1992; it is not just a matter of having tactical nuclear weapons but also the ability to get them to where you want them both in terms of providing platforms with sufficient range and penetration capability.

  25. What happened to the WE177 Vaults under the HAS complexes at Marham? Are they still used for Storm Shadow for example?

  26. As people are mentioning tactical nuclear bombs, what is this dropped in Yemen? Is this for real? If so, why no news coverage?

  27. Think this is one of the two ammo dumps recently destroyed in Yemen.

    Lots of different camera angles of the same piece of featureless hillside suggesting the event was known of beforehand.

  28. If a low yield sub-strategic nuclear weapon is delivered by free-fall bomb from an unseen aircraft or by Trident SLBM what’s the difference? The effect and end result are exactly the same.

  29. Hi Ravenser. I do not agree.

    The aircraft may go u/s. The airfield may be negated. The range of the aircraft is limited. The response time is limited for an aircraft to take off if a First Strike Scenario returns. Stealth aircraft are not invisible. The aircraft may be shot down. None of these apply to an SSBN which can hide at leisure and retaliate at leisure. That is the very essence of deterrence.
    The issue for most people is cost, but if this nation wants to be a P5 member with armed forces to match then spending money on the forces should not be an issue. The cuts to the forces in modern times are a disgrace already, despite the vaunted 2% waffle.

  30. @Ravenser the problem is not delivery mechanism in relation to target effects. The problem is the trident delivery system in relation to what the Russians think is going on when you launch one. Using a trident missile has the potential to trigger a retaliatory strike from your enemies who don’t have the luxury of time to distinguish between a threatening and “non threatening” nuclear launch as it relates to them.

    Given that the most nuclear states have not significantly relaxed their nuclear postures since the end of the cold war – ICBM’s in particular have remained on a hair trigger – the potential for triggering an adverse reaction is too strong.

    I think the use of chemical/biological weapons by rouge state actors would not require the use of a tactical nuclear option. Any event like this is likely to incite a response in co-ordination with the US which lends enough conventional firepower to overwhelm the majority of potential aggressors. Also hitting a target country would require the submarine to move a significant distance from its normal patrol waters to hold such states at risk without overflying other nuclear armed state. Thus it would lose it’s value as a deterrence against Russia during that period.

    Re-manufacture of an existing warhead design is not trivial. The US recently forgot how to make key components of the W76 warhead ( and the investment required to restart that process has been immense.

    I may be mistaken in this but i though the primary way to reduce the yield of a weapon and make it “cleaner” in term of fallout was to reduce the contribution of tertiary fission yield, not the fusion component. As the trident warhead is rumored to be a copy of the W76 design which employs a depleted uranium tamper, surely the technical solution would be to replace this with tungsten or lead.

  31. Thank you for your input Mark and Daniele,
    So, focusing more on the method of delivery as opposed to the target effects. What would be the most efficient delivery method? Stealthy positioning but highly detectable submarine launch or detectable positioning with stealthy aircraft delivery? Or could both have a place depending on the conflict scenario?
    Forgive me I don’t have a foot in any particular camp, I’m more devil’s advocate and feel it’s a subject worthy of further debate.

  32. A big problem with the idea of a limited nuclear war, between two nuclear powers, is that the moment either party indicates an unwillingness to escalate further, it essentially means unconditional surrender.

    If you limit your options while your opponent is still prepared to up the stakes, the deterrent effect of your remaining arsenal vanishes. You are then subject to coercion under threat of further nuclear attacks.

    You face the prospect of runaway escalation if you attempt limited action; but if you’re not prepared to go all the way, you’d probably be better off surrendering early than if you blink after taking a good nuclear kicking.

    That said, it’s almost inconceivable that the UK would give up the minimum response option for its nuclear weapon system. It’s widely speculated that the British warheads are variable yield, and that missiles with a single warhead would be in the Vanguard’s payload.

    When the UK did field hundreds of tactical nukes, they were there to be used against massive conventional forces. Many of those nukes would be obsolete now after the development of smaller guided and sensor fused conventional munitions.

    If you are concerned about attack from mass conventional forces, it would be cheaper, and probably politically easier, to tear up our pledges on mines and cluster bombs. Introducing the US sensor fused cluster bomb, reintroducing MLRS cluster bombs and anti-personnel mines and other weapons would provide differently devastating options that could be fielded in place of a great many of the tactical nuclear weapons of the past.

  33. Mandelli, just because something is a mushroom cloud does not mean it’s a nuke. The mushroom shape is simply due to thermal effects, even fuel explosions can cause a mushroom cloud. And “neutron” bomb is simply sensationalist nonsense. You think that guy is going to walk around after being so close to a weapon designed to give out an intense lethal pulse of radiation? More likely some party trying to slander their opponents.

    Obsvr, I do agree that in certain cases, judicious use of (very) highly explosive material is useful, but while technically pragmatic, there is also the effects of nuclear weapons usage on the political and diplomatic stage. It’s going to take a very strong (and suicidal) government to throw away their chances in the next election and cause the alienation of most of the world simply to deploy weapons that are so controversial when there are other means (like simply tearing up the convention on certain weapons and going back to cluster munitions like others have already mentioned) that do not have the capacity to push the war into a strategic level MAD exchange.

    So in short, it’s not really the technical limitations of tactical nuclear weapons that is limiting their usage, it’s more the local and international condemnation that is going to result from their use.

    North Korea might send their congratulations and admiration though. :)

  34. I for one don’t believe the B61-12 is really a tactical weapon. I believe it’s a strategic weapon masquerading as a tactical nuke. The high accuracy and penetrating capability of the weapon mean it’s suited for counter force and decapitation strikes.

    It is a weapon primarily designed to let the US quickly introduce a lot of uncertainty for the other side of things escalate and provide more options to US planners in my view. F-35 internal carriage is extremely valuable here as there will be a ton of F-35’s and you won’t know what they are carrying until it drops the thing on your head. Never mind the implications for something like the B-21 which presumably could carry more B61 than B83 due to the much smaller size of the weapons.

    I don’t see the tactical weapon at all honestly. This isn’t a weapon to be dropped on an Army bridgehead or mechanized concentration. It’s a counter force weapon and in that construct it’s perfectly logical.

    It also makes no sense for the UK because the British arsenal isn’t large enough and the delivery platforms aren’t numerous enough to engage in counter force strikes. But for the US let’s say that North Korea develops a few dozen hardened in ground silo ICBMs and some form of early warning for incoming ICBMs. They adopt a launch on warning posture because they are crazy. This gives you an option there. Hell even China might be vulnerable to a disarming strike if the US actually builds enough B-21 and has enough F-35’s on its carriers and forward deployed. They don’t have all that many weapons.

    Tactical nukes in my mind are largely not necessary. The problem they solved, killing a large mobile land force with having to amass huge air or land assets yourself, is somewhat solved by conventional weapons now.

  35. Don’t forget that Britain was planning to replace WE177 with SRAM-T. The end of the cold war led to its cancellation, as it was “the end of history” & no more conflicts would be fought. Yes, well…….
    The SRAM-T would have had the W91 warhead, reported as a selectable 10kt or 100kt yield, weighing 310 pounds. It used TATB insensitive explosive & a fire resistant pit. It was the last new US nuclear weapon to get a model number designation. The UK probably had access to this, as part of the proposed SRAM-T purchase.
    A small number of LRSO with the W91 warhead, would be a flexible response for either/both the US & the UK.

  36. Been musing about tactical nukes. It reminds me that I loathe the use of the term “strategic bombing”. It’s an oxymoron. The flip-side is that all bombing is therefore tactical.

    However, the sheer scale of a nuke means that using it as a mere part of a grand plan means your force must be massive.

    For this reason I tend to agree with JMH. It makes little sense for the UK.

    I can only think of a “backed into a corner” and “need to escape” use.

    But even then I concur with others in that cluster munitions are probably more appropriate in many instance – I have no idea why we signed up to the CCM – may as well ban bullets too!

  37. JMH, the B61-12 won’t have a tactical / sub-strategic designation.

    And originally, the B61 and WE.177 were both part of a single strategic bombing plan. Able to be carried by smaller, faster aircraft; designed for very low-level release to improve accuracy; those bombs were needed to take out air-defence and control assets.

    The need for those weapons reflects the deficiencies of aircraft like the B52, which were only any use for bombing cities, and which could only be expected to get through in a second wave after Soviet defences had been softened up by the initial and more precise strikes. Also reflects the relative inaccuracy of earlier generations of long-range ballistic missiles – still requiring the element of accuracy provided by small fast jets dropping bombs at very low level.

    Trident D5 is very accurate compared to previous generations of ICBM/SLBM.

  38. No comments so far about the cost of these submarines. Surprising really given that they are set to cost £31bn (plus £10bn contingency) which is more than the cost of the entire surface navy put together. I took a quick look at the paper on the French nuclear force – it says “The cost of procuring the new Triomphant class SSBN, through life, was estimated by The Bulletin of the Atomic Scientists at approximately €16bn, including construction, maintenance and personnel over 25 years.” Given that the last 4 Astutes will cost £1.5bn each (DE&S this year) how on earth can such a huge cost be justified? I know its pissing into the wind to say this now but a stretched Astute with a battery of vertical launch tubes would surely not cost much more than £2bn and be a far lower-risk venture than Successor. A stretched Astute would easily hold a Polaris size ballistic missile, perhaps, at a stretch, a Trident-1 even. Too late now to consider these alternatives but it is a scandal that we have just blindly accepted like-for-like regardless of the cost.

  39. Hi Steve
    I imagine a large share of the cost is the continued development and sustaining of skills and facilitates for the nuclear warhead supply chain. The high tempo for SSBN ops when compared to SSN’s is likely also a factor in relation to ongoing costs of operation.
    There will also be significant pressure for the successor SSBN to be a further step in capability beyond Astute as the hulls will need to remain viable for a longer period of time. There are also propulsion related limitations to Astute class boats that we would have to rectify with R&D prior to the design being given the go ahead.
    The presence of nuclear weapons alone also significantly increase the security costs of operating the SSBN fleet relative to attack subs.

  40. @Mark – Those all sound like good points re Steve’s references to Astute costs but what about his comparison with the estimate for French total-life cost of their SSBN program? That comparison sounds very stark and they (the French) also need to address all the SSBN vs SSN increased costs that you mentioned don’t they?

  41. A good question Julian. I think we have two factors at play.
    The first is that the full quote in the report is not actually the life cycle costs of the deterrent including the missiles and bits that go pop. I am also unsure which components are included in the £31bn cost number? For instance in relation to the €16bn figure there is some ambiguity as the total cost of the system is significantly higher

    “The cost of procuring the new Triomphant class SSBN, through life, was estimated by The Bulletin of the Atomic Scientists at approximately €16bn, including construction, maintenance and personnel over 25 years. If the cost of the missiles and warheads is incorporated, that estimate is thought to double to approximately €32bn” (Source: )

    Another compounding factor is inflation and the relative exchange rate. The figures I see quoted for the Triomphant-class boats is ~€17.1B in 2006 euros for construction costs only ( bwhich again conflicts with the BAS report! That equates to about €20.14B into today’s money which equates to roughly £18.77Bn of the queens shilling.

    This equates to ~£4.61B per Triomphant-class boat in today’s money for just the boat and roughly £8bn if we double up to include the missiles and the warheads. That would suggest that a figure of £32bn for four boats plus all the accessories would not be unreasonable compared to the french.

    I have only been able to have a quick look at this in my lunch break so I will maybe do a bit of further digging into this and get back to you with some more conclusive findings in the near future. If the boats costs seem excessive @ThinkDefence may consider a joint post about the use of watertight ISO containers to house the D5 II….. The possibilities.

  42. Don’t forget the PWR 3 reactor being developed for successor. If the PWR 3 turns out as good as billed, then maybe it is time to look at nuclear powered surface ships again? I know the experiments in the late 50s/60s did not go well, but the reactors needed frequent refuelling (expensive) then. Now they do not.
    A new batch of T45 powered by PWR 3?

  43. The US GAO issued a report back in 1998 comparing the life cycle costs of conventionally to nuclear powered aircraft carriers and concluded over the 50 year life cycle the nuclear option was 58% more expensive.
    Would be surprised if the the new generation reactors could close the gap. The latest CVN 78 Ford is officially meeting its cost cap imposed by Congress of $12.9 billion in then year dollars, $15.0 billion in 2014 $ with further major spend required after delivery to make operational.

  44. @TON
    Don’t forget that 1998 was a generational low in the oil price – $10. They did a propulsion study in about 2007 that was updated 1-2 years later – a lot depends on what kind of ship it is. Nuclear works best for big ships that do a lot of steaming and have lots of toys like big BMD radars. Amphibious ships don’t travel enough, frigates are too small, the sweet spot was for big cruisers where the breakeven was around $70 oil from memory.

    But there’s also the non-financial aspects of Z berths and nuclear-qualified crew, which is something we’re struggling with as it is. I quite fancy an AON – a tanker with a couple of Ford reactors in it, coupled to this new technology for making fuel by electrolysis. Wouldn’t be enough to support surge operations, but could make a carrier group self-sufficient in fuel for the escorts and basic AEW/CAP.

  45. Re: The cost difference between the Astutes and SSBNs, you also have to factor in the point that an SSBN is twice the size of an Astute and *four* times the tonnage. That is a very big difference even in simple material costs.

    It’s often hard to compare program costs since different programs have different criteria. For example, one program can estimate a lifecycle cost of 20 years, some use 25 or 30. Some assume monthly maintenance on certain items, some biannually, some annually etc. Some reports don’t even do that and give off the shelf purchase price.

    Hard to compare. Best thing to do is just ignore the rest and compare your own estimated costs with your budget, not other people’s. After all, the most important criteria isn’t if “they can make it cheaper” but “if we can afford it”.

  46. @TOC You might be a bit less keen when you see the cost. :-) If you say that nuclear is 25% more than conventional, the electrolysis process is only about 30% efficient so you’re looking at 3.75x the cost of fossil fuel – but then you have to set against the costs of escorting tankers to the battlegroup and the greater flexibility. Probably the sort of thing that might make sense for the Septics to have the odd one for the Pacific rather than becoming the norm for us.

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