Why are the brits wasting money on sea viper?

yes jonsey, i take it very literally. i want to show that the correct comparison is not apar vs sampson but apar+smart-l vs. sampson+s1850m.

and afaik x-band has a superior low altitude detection range because of the propagation effects but maybe i’m wrong. of course other typical x-band characteristics like a very wide frequency bandwidth and a small beamwidth also helps a lot.

i think it’s not true that sampson can act as a long range vsr and as a mfr at the same time. sampson is able to do both, thats no question but if for example it is used in a long range volume search mode the performance of all the mfr tasks is greatly reduced.

I think you may be taking this too literally Radar. I think the point is that, as an s-band rotator, Samson is more able to act in a volume search mode than a fixed x-band array. In much the same way as the x-band is more suited to the task of CWI for a semi-active missile than the s-band set!.

btw. from my understanding x-band is preferable in terms of horizon search. sampson can gain some extra height but s-band is not the best choice for doing a horizon scan.

That would depend on what you term ‘better’. The x-band is likely giving a higher datarate and fewer false alarms owing to its superior resolution. Against that the s-band is seeing further over the horizon and providing earlier warning!. Personally i’ll take the range edge every time. Other people’s opinions differ though!.

i think it’s not true that sampson can act as a long range vsr and as a mfr at the same time. sampson is able to do both, thats no question but if for example it is used in a long range volume search mode the performance of all the mfr tasks is greatly reduced.
thats a common position.

e.g. http://navy-matters.beedall.com/sampson.htm

BAE Systems have also claimed that Sampson eliminates the need for several separate systems. They suggest that on the Type 45 destroyer, the Alenia Marconi Systems/Signaal S 1850M long-range 3D radar that is designed to work in partnership with Sampson “really is superfluous and is not needed to perform the mission of the ship”. BAE Systems believes that the reason the large volume search radar has been incorporated in to PAAMS is “more of a historic nature, associated with [the] work sharing issues” that were a huge problem during the trilateral Project Horizon

This claim is rather an over simplification. Some tasks are difficult to combine, for example (long range) volume search takes a lot of radar resources, leaving little room for other tasks such as targeting. Combining volume search with other tasks also results either in slow search rates or in low overall quality per task. Driving parameters in radar performance is time-on-target or observation time per beam. This is perhaps a the key reason why the Royal Navy selected the S1850M Long Range Radar to complement Sampson on the Type 45 destroyers. It is also a reason why NATO in its NATO Anti-Air Warfare System study (NAAWS) defined the preferred AAW system as consisting of a complementary Volume Search Radar and MFR. This – as NATO points out – gives the added advantage that the two systems can use two different radar frequencies; one being a good choice for long range search, the other a good choice for an MFR (which is especially nice as physics makes both tasks difficult to combine).

i don’t think that the s1850m can really act as a backup for sampson because there is no chance to control a aster with it. so if apar/sampson fails both ship-types are toothless. if the smart-l/s1850m fails, the type 45 are in a better position than the apar-equipped ships.

btw. from my understanding x-band is preferable in terms of horizon search. sampson can gain some extra height but s-band is not the best choice for doing a horizon scan.

Indeed, a Type 45 with 96 cells would be an incredible combination. Although keep in mind there is room for 72 cells IIRC and these could be fitted at a later date or they might not be.

Also, not all 96 cells of the Arleigh Burke are going to be loaded with SM-2s. Those cells are filled by Asrocs, Tomahawks and four of them are taken up by sixteen ESSMs too. Every single cell on the Type 45, however, is filled by an Aster. So the levels of actual area defence anti-air missiles from a Burke to a T45 might not differ by that much.

For Type 45 destroyer, the existence of SMART-L is mainly for back-up ~ SAMPSON itself could do the jobs of APAR at the distance and with the targets’ processing capability of SMART-L in the same time.

It is really a pity that Type-45 doesn’t carry as many VLS as a DDG-51…….:D

Ah, that does make some good sense. So the reduction in terminal phase capability in the radar is compensated for by ability in the missile, making X band + ARH missiles effectively pointless.

That would also explain why, unlike its German and Dutch sisters, BAE state the Type 45 doesn’t actually need the S1850M as a dedicated VSR since SAMPSON operates at a bandwith capable of fulfilling both roles to the ability required; while the De Zevens and F124s genuinely have a combined system which can’t operate independently in the event of a failure:

APAR has too small a wavelength to act as a proper search radar and SMART-L operates at too high a wavelength to achieve high kill probabilities in the terminal phase against highly maneuverable targets, while SAMPSON can do both.

The Uncertainty principle is a b**ch. :p

All contrary evidence to the title of the thread it seems.

Out of interest though, why did the RN decide to go with SAMPSON in the S band? APAR operates at X band, the smaller wavelength meaning that tracking capability is increased although range is decreased, but this is offset by SMART-L operating at a high wavelength.

So why did the RN decide to go with both the S1850M and then also give SAMPSON a longer range at expense of tracking efficiency?

X-band offers the higher resolution necessary for terminal phase target illumination – an obvious necessity for a ship mounting a semi-active missile. S-band offers better range performance and, in concert with the lightened dual-face array’s ability to be mounted atop a significant height mast, allows for superior radar horizon performance. The drop in resolution with the shift to the lower frequency being inconsequential for UKPAAMS as the missile has its own active seeker for the endgame.

Essentially the UK had the MESAR radar research program in the works since the 80’s and it was offering fantastic capabilities in track forming and handling. We wanted to leverage that into an operational capability and saw no more capability on offer from the PESA radars from France or Italy or from APAR – a set clearly optimised for SM-2 employment. We had had the Falkands experience with Argentine a/c defeating GWS30 and had seen the impact of fire-channel dependency with GWS25 and, consequently, liked the idea of an active seeker missile. S-band with a cutting-edge, local, radar solution linked to an active missile that the French and Italians were paying to develop seemed a winning solution all round.

Out of interest though, why did the RN decide to go with SAMPSON in the S band? APAR operates at X band, the smaller wavelength meaning that tracking capability is increased although range is decreased, but this is offset by SMART-L operating at a high wavelength.

So why did the RN decide to go with both the S1850M and then also give SAMPSON a longer range at expense of tracking efficiency?

Type 45 has SAMPSON AND SMART-L (jn the form of S1850M, which is a variant of SMART-L).

The RN didn’t choose SAMPSON in place of both APAR + SMART-L, but in place of APAR, alone.

http://www.thalesgroup.com/smart-l/?pid=1568

SMART-L’s derivative, S1850M, is currently being installed on the Royal Navy’s Type 45 vessels and the French and Italian Horizon class destroyers

APAR can track 200 air targets within the range of 150 km.

SMART-L can search several hundred of air targets within the range of 400 km+.

The UK navy wants of all of the capability mentioned above (= searching and tracking several hundred of air targets within the range of 400 km+) in one radar, that is why it chooses SAMPSON.

Aegis wasn’t originally available for NATO. APAR didn’t meet UK requirements (but was a lot cheaper), hence the need for SAMPSON and SMART-L.

which requirement is not met by apar+smart-l?

In what way were UK requirements significantly different from those of France and Italy?

The RN set a very high bar for what it wanted in its next AAW system. Its one of the multitude of reasons that the Horizon project was abandoned by the UK, France and Italy where happier with a slightly less good capability.

Whether this was the right decision is a matter of debate. As the only one of those three nations to have come under air attack “recently” the RN took a different view and wanted more.

The RN at the time of the order and at present is centered around distant expeditions and intervention forces, providing a very high level of AAW even without the presence of a carrier is seen as crucial.

France & Italy have not bought APAR. It’s been bought by the Netherlands, Germany, & Denmark.

Aegis wasn’t originally available for NATO. APAR didn’t meet UK requirements (but was a lot cheaper), hence the need for SAMPSON and SMART-L.

In what way were UK requirements significantly different from those of France and Italy?

Aegis wasn’t originally available for NATO. APAR didn’t meet UK requirements (but was a lot cheaper), hence the need for SAMPSON and SMART-L.

other participants from the nfr-90 decided to develop apar. so there were other paths out than only aegis for naaws.

Indeed. The question was why not aegis though not APAR. Presumably like the approach the Spanish took.

Simple answer is that we needed more capability than AEGIS/SPY-1/SM2 offered when the competition was run.

other participants from the nfr-90 decided to develop apar. so there were other paths out than only aegis for naaws.

As per Swerve’s point, the decision was made over a decade ago, the money was spent when the country was doing very well financially, there was no need to consolidate at the time because there was a great deal less financial constraints.

All in all, not a very well thought out question, going with Aegis now because of the financial situation we are in would involve wasting money spent on sunk costs and spending more money on top of that.

The question is meaningless, in the terms in which it is posed. We’re not ‘wasting money on Sea Viper’, even if buying it was a mistake. The money has been spent, & We have the system, paid for, in service & ready for use.

Simple answer is that we needed more capability than AEGIS/SPY-1/SM2 offered when the competition was run.

The SPY-1x/SPG combination is vastly inferior, in ship-to-ship terms, than UKPAAMS. The BAE Sampson array is seeing further over the horizon and the active missile has no fire-channel constraints.

To the USN this is no issue as they have the simple expedient of just deploying more and more AEGIS ships until the threat is met – also they can rely, pretty much, on the presence of a friendly E-2D and CEC. The RN cannot rely on such luxuries being present so the need is for the shipboard system to be making up some of the shortfall.

Had the offer, at the time, been equal participation in SPY-3 and an offer of SM-6 then, perhaps, the decision may have been different, but, that is the level of capabilty we required and that is what we have with Sea Viper.