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UK military spending review   General Military Discussion

Started 13/3/21 by autogun; 13983 views.
graylion

From: graylion

9-Jun

DavidPawley said:

No, it was just shitty workmanship and no QA, not stitch welding. The hulls were not within spec and that's why they weren't accepted. Running gear couldn't be installed because hull out of true is one complaint I recall.

where were they built?

DavidPawley

From: DavidPawley

9-Jun

Spain. Shipped to UK to be mated to other components.

RovingPedant

From: RovingPedant

10-Jun

The hulls are built in Spain and the assembly is in the UK (Wales to be specific) but I don't know exactly where the split is. I suspect that running gear and power train is fitted in Spain before shipping ( it would be a pain to move around otherwise) while turrets and electronics are fitted in the UK. Consequently much of what is reported, if true, is an internal problem for GD, provided that they don't try to ship it to the MoD in that condition. That said one of the official reports noted that much of the noise and vibration generated by the platform originates with problems with the drivetrain and running gear*

I've seen complaints about engineering problems before and often they are either not true or an extrapolation from what is true based on a lack of engineering knowledge, so I prefer to wait for a bit more detail before flying off the handle. The QA problems with Ajax fabrication have ranged from welds being the wrong length (quite possible but not ideal if you're stitch welding) to the hull sides being different lengths (pretty difficult if they're being cut on anything like modern machinery) to welded bosses being true to each other but variable to other features (very common on previous generation AFVs - you'd like to think we've tightened up general tolerances a bit) but people like to take that kind of information and create an impression of tacked together wriggly tin  with chewing gum stopping the more egregious leaks long enough to get it out of the factory.  I don't think Ajax is perfect but it strikes me that it's something that can be fixed.

*It must be borne in mind that noise and vibration on all tracked vehicles mostly originates with the drivetrain and running gear, even when it's working perfectly - it's fundamentally an awful lot of metal being thrown around at high speeds and lots of metal-to-metal impacts.

schnuersi

From: schnuersi

11-Jun

Such problems really are not uncommon.
As soon as multiple companies are involved things get messy quickly. If its multiple companies from multiple countries it gets worse and if its multiple companies from multiole countries from multiple cooperations its an invitation to disaster.

Several of the current multi national projects suffer from this. Even the ones concidered successfull.
I for example know that the final assembly of the Boxer is a nightmare because this is where the parts produced all over Europe come together. Especially the mission module and the hull. The latters often don't fit. Some workers told me they usually don't fit. The tollerances are defined and given as per international norm but there are local interpretations and preferences. This is enough to cause quite a lot of trouble.

RovingPedant said:

That said one of the official reports noted that much of the noise and vibration generated by the platform originates with problems with the drivetrain and running gear*

That really is rather problematic. Vibration problems usually are because of the interaction of several parts. There often is no single source or cause. This can be very tough to pinpoint and fix. It seems strange though that Ajax has such troubles since its based of an exsiting and mature vehicle. This hints at either poor integration of systems and modifications or changes to the basic layout without proper analysis and testing. If the latter is the case these proplems might not be fixable at all without a major rework.

autogun

From: autogun

11-Jun

schnuersi said:

As soon as multiple companies are involved things get messy quickly. If its multiple companies from multiple countries it gets worse and if its multiple companies from multiole countries from multiple cooperations its an invitation to disaster.

One of the other problems with Ajax has been the ammo feed to the 40mm gun (I don't know if it's been sorted yet).

The story I have heard is as follows: CTAI designed their ammo feed together with the gun. The French adopted the CTAI package unchanged and it works just fine, but LM, who won the British contract for the Ajax turret, decided to design their own feed. Not good...

RovingPedant

From: RovingPedant

11-Jun

schnuersi said...

That really is rather problematic. Vibration problems usually are because of the interaction of several parts. There often is no single source or cause. This can be very tough to pinpoint and fix. It seems strange though that Ajax has such troubles since its based of an exsiting and mature vehicle. This hints at either poor integration of systems and modifications or changes to the basic layout without proper analysis and testing. If the latter is the case these proplems might not be fixable at all without a major rework.

It could equally be quality control problems which are possible to fix. Checking the published noise and vibration review, https://www.gov.uk/government/publications/ajax-noise-and-vibration-review, it states:

62. Noise and vibration in the Ajax family of vehicles have both electrical and mechanical origins from the following broad sources:

  1. Track, suspension and running gear, in particular the tension and sprocket design/track interface.

  2. Engine and its mounting into the vehicle.

  3. Quality issues associated with, but not limited to, inconsistent routing of cabling, lack of bonding and weld quality; all of which can lead to potential electromagnetic compatibility issues with communication equipment. As witnessed during trials, insecure components and bolting within the vehicle can also lead to noise and vibration, and again this was noted by ATDU crews.

  4. Headset performance and integration (noise only).

It looks like the reviewers have an idea of where the problems are and those noted are mostly things that can be addressed and finessed without starting afresh, the engine being questionable.

RovingPedant

From: RovingPedant

11-Jun

autogun said...

The story I have heard is as follows: CTAI designed their ammo feed together with the gun. The French adopted the CTAI package unchanged and it works just fine, but LM, who won the British contract for the Ajax turret, decided to design their own feed. Not good...

If you see the interior of the EBRC turret it looks like while they may have been to CTAI for the ammunition feed it's a feed system that hasn't been shown for any other installation i.e. it's a new or modified arrangement, not an existing one.

https://i0.wp.com/militaryleak.com/wp-content/uploads/2021/06/nexter-unveils-jaguar-ebrc-reconnaissance-vehicle-with-new-wire-cage-armor-1.jpg?ssl=1

Still, the weapon manufacturer ought to be able to integrate an ammo handling system to their weapon better than a third party.

 

autogun

From: autogun

11-Jun

Yes, you may be right that the French feed was not the original one, but it was, I believe, designed by the gun designers.

In reply toRe: msg 77
autogun

From: autogun

28-Oct

It has risen... https://www.overtdefense.com/2022/10/26/delays-to-uks-puma-replacement-tender-but-ajax-trials-restart/

The UK’s troubled AJAX armored fighting vehicle program has restarted after safety concerns for personnel halted the trials phase back in March. The safety issues included noise and vibration issues which left soldiers with permanent injuries. In May the In June, the Public Accounts Committee found that delays had been caused by a “litany of failures” and advised that the Ministry of Defence needed to resolve the issues or scrap the project.

In a statement to Parliament Minister of State For Defence Procurement, Alec Shelbrooke explained that the government’s concern is “the safety of our personnel, which has been at the forefront of the work that has been ongoing over the summer,” he continued “I am pleased to be able to inform the House that, following agreement from the AJAX Safety Panel, this work has led to resuming the User Validation Trials paused earlier this year and since Monday 10th October there have been eight days of trials.”

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