Comet tanks - fault

The 23rd Hussars were the first outfit to receive the new Comet tank, which started arriving in late 1944.

According to my Dad, who was a fitter in 'C' Squadron, the drive sprocket bearings had to be replaced on ALL of them before they could be used.

This was a particularly arduous task and would take a team of fitters an evening to service a single tank.

Given that the Comet was based on the tried-and-tested Cromwell chassis, and presumably had also undergone extensive testing itself, I find this rather strange.

Has anyone else heard of this incident and offer any explanation for the cause? (Dad has not ruled out sabotage!)

 

Well, one thing I do know is that the Comet's top speed was "governed" down from the Cromwell's ~40mph to 32mph to "preserve suspension and engine components"...

 

the later cromwell's were also governed down to 32mph and as far as i know the comet uses the same z5 merritt brown box and 15.5 inch track as the later cromwell's so maybe the problem was due to incorrect oil or low levels in the final drive but it's just a guess

 

Rick, the Comet had an 18" wide track - Comet Cruiser Tank (A.34)

As you can see, not only were the Cromwells, all marks, narower - the tracks themselves were a lot lighter - Cromwell Cruiser Tank (A.27(M))

 

my apologies for being wrong, the trouble is i don't own a comet but i do own a mk6 cromwell and i was fairly sure the tracks were the same but i had assumed that because the 15.5" cromwells are referred to as the wide track versions that the comet would be the same but now that i think back on it the comet track does actually look different. i'll have to buy one so that i can better compare them in future

thanks for the corrrection

rick

 

Hmm, track weight...

The Comet's is just over a ton and a half in weight, at 3600 lbs.

Most Cromwell marks are just (sic!) a shade over a ton, at 2285 lbs...apart from the III and I presume Rick's Mk6 at 1 ton, 400 lbs.

Thus the Comet's track weighs 1,000 lbs more than the heaviest Cromwell type...

I wonder was the Cromwell bearing used in the same application, with no thought for the extra loading??? It might have survived the Comet's testing phase...THEN calved, hence the sudden panic swap-out.

Strangely enough - it's not the first time I've heard of this - time for a modern parable...

In the mid 1980's, when Harley Davidson were introducing their "Eevoultion"-engined Sportster models, they went to a new-style (for Harley) Single-spring clutch designed for them by Speedwell in England. As well as the 883cc Sportsters such as I bought, they intended to market a big-bore 1200cc Sportster....and proceeded to bore out a dozen 883s and test them over 50,000 hard testing miles in UK road conditions, expecting it to be a shoo-in...and they proceeded to spec up a production line for the 1200 item while the test was going on....

And at or around 49,500 miles, all twelve 1200s blew their clutches!

It was too late to halt the production of the new big-bore item, so while they sent Speedwell abck to the drawing bord to design a new item (which would take some months to design AND test again - Harley got a big-bore Sportster onto the showroom floors by the simple expedient of plying the keyboard on their fancy new CAD machines - and for one year only built and marketed an 1100cc Sportster! Just enough horsepower less to allow the original-spec clutch do its job properly.

 

i'll ask around with regard to the final drives on the comet and cromwell and see if they are the same, i'll let you know when i find out.

rick

 

Thanks for your input, guys.

This weekend I showed Dad the extract from the 21 Army Group Admin history (thanks von Poop) - he said that is just flat wrong.

The fault was definitely with the rear drive sprocket - they were sent replacement bearings, not wheels - there was no problem with the tensioner wheels.

Make of that what you will!

 

There are conflicting accounts here: does anyone have access to original documentation that describes the fault i.e. was it the rear drive sprocket bearing or the front tensioner/idler wheel ?

 

I talked to Dad about this over the weekend. He recounted his story:

The fitters were based at Armentieres while the main body of the 23rd Hussars were living it up in Ypres. This covers a period just before Christmas then mid-January to mid-March (in between there was the small matter of the Ardennes battles which required the Hussars' attention).

The fitters were billeted in a school (infants, he thinks) and used a workshop that had previously been in use by the Germans (there were numerous posters extolling the virtues of hard work). The Germans had built a mock village on the roof as camouflage, constructed from canvas on wooden frames. Dad described it as a masterpiece - it even had people's faces peering through the windows of the fake houses. The photograph below, if not the actual building, is very much like it. He remembers the 'saw-tooth' roof.

A team of 4/5 fitters would work on a tank and it took them all night to replace the roller bearings on the rear sprocket wheels (Dad described the procedure, but I will omit the details here). He cannot remember what was done with the defective bearings.

One night a sprocket wheel fell onto the foot/lower leg of a fitter, Jack Lee (of whom I have a photo - inscribed 'Jack Lee, Armatieres [sic]'). His injuries were so serious that he eventually had his lower leg amputated.


Now:

• There is no mention of this episode in the Hussars' War Diary,
• There is no mention of it in the Hussars' Regimental history,
• The Administrative History of 21 Army Group states:

"All formations were fully equipped several days before the commencement of the operation [PLUNDER], except for the Comet tanks of 29 Armoured Brigade which were reported operationally unfit owing to defects in the tensioner wheels. Arrangements were made with the War Office to provide new type wheels which were flown to the theatre in first priority air freight direct from the factory. Each day's consignments were collected under brigade REME arrangements and fitted to the tanks within seven days in time for the operation."

• There is no mention of Jack Lee's injury in the Hussars' casualty lists.

Given the above details I suggest there are three possible explanations:

• Dad made the entire story up,
• The whole episode was deemed to be of insufficient importance to merit a mention,
• There was a cover up.

If the spare bearings were ordered direct from the factory, I'd be interested to know if there might be some records over here which could corroborate Dad's story (he mentioned a firm called Timkins/Timpkins?). Personally I don't doubt his word for one minute, but I must act in the interests of objectivity.

 

I'm inclined to agree with your Dad. All of the photographic evidence of Comets in action in WWII (someone is now bound to come up with something different!) supports his account of events i.e. all photographs of which I am aware show the early idler, implying the fault was with the rear sprocket bearing.

Timkins was/is a company manufacturing bearings, again supporting your Dad's view.

The answer may lie very close to where you (Grimmy) live. Comets were built at Leyland Motors and I understand the Commercial Vehicle Museum in Leyland hold a large number of Comet-related photos and possibly documents (never had the chance to visit so don't know how accurate this information is).

 

The answer may lie very close to where you (Grimmy) live. Comets were built at Leyland Motors and I understand the Commercial Vehicle Museum in Leyland hold a large number of Comet-related photos and possibly documents (never had the chance to visit so don't know how accurate this information is).

Thanks for that. I've checked online but it seems Leyland Motors archives only hold documents dated 1946 onwards. However I think it may be possible to contact men who were working there at the time, some of whom, as you say, may not live very far away.

 

There is a 'Leyland Forum' and I left a message there a couple of years or so ago. Prompted some response from people who had worked on Comets. My posting was for general information if I remember correctly and not to do with the Comet fault.

 

I joined Leyland Forum yesterday!

I knew an awful lot of Leyland Motors workers when I was a lad. I'm hoping to track down those who are still around.

 

Grimmy

You are bound to find the Leyland Forum helpful. I understand the Museum has a collection of Comet tank photos that need collating! By way of trivia I also understand that the post-War Leyland Comet truck was named after the tank of the same name!

 

There are also roads named 'Comet Way' and 'Centurion Way' near the plant.

 

I'd be interested to know if there might be some records over here which could corroborate Dad's story (he mentioned a firm called Timkins/Timpkins?).


Timken???

Timken Company - Wikipedia, the free encyclopedia