I was over reading The Historian's interesting and timely thread regarding a special TV broadcast regarding the discovery of some previously unknown German D-Day bunkers...Map Solves Mystery of D-Day Massacre

....anyhoo, in that thread, he posted a link to a page with this photo, which is a screen cap from Saving Private Ryan




Now, whenever possible, I try not to get my history from the movies, but I thought this photo was interesting because it shows some modifications to Sherman tanks that I have not seen before - specifically, the the big-honkin' risers on the back end.

Here's a detail



Now, I have heard of (but never seen) a Sherman duplex-drive, which were fitted with auxiliary propellers and a waterproof, canvas 'gunwale' to displace enough water to float the tank and, theoretically at least, make it to shore.

I've also, on this forum, read of the Sherman Fireflies, which, to my understanding, were British modified (i.e. upgunned) Shermans.

Now, bearing in mind that these are pictures of movie 'props', they are undoubtedly trying to represent something that has a basis in fact The risers appear to be either schnorkels or exhaust risers -

so, a quick, easy question to the 'big-iron' mavens on the board...


....whatupwitdat?????

-whatever

-Lou

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5 out of 4 people have difficulty with fractions.

What you see is a "deep wading" kit on a Sherman. I don't think this was actually used on D-day. What it does is allow the tank to wade in from a fairly deep off-shore surf. The big trunks you see cover the engine intakes. The exhaust is fitted with one-way valves to prevent back flooding from that side of the engine. The tank itself is sealed and a bilge pump is installed to keep flooding from happening.

never noticed there was allied tanks in SPR besides the last bit.

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Time is only enemy you'll never get rid of.

They were used on D-Day, as were the DD Shermans. The deep wading kits met with various degrees of success.

After moving inland, the deep wading kits and DD skirts were removed. One thing to look for with DD Shermans is the idler wheel.

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Okay.... let's pretend, just for a minute, that I'm really stupid.




....which one is the 'idler wheel'?

-whatever

-Lou

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5 out of 4 people have difficulty with fractions.

Right there......

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Heres a pic of Some DDs in the water...


There was also a DD Variant of the Valentine...

I would have loved to see the faces of the German defenders on D-Day when the saw the DDs rising up from the sea.

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"This Guy Fawkes bloke, do we let him off or what?"

nice pics Joe!

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This is a pair of Dutch resistance crystal radios, built into a small metal can, and a matchbox. The image is from a postcard bought at a Dutch Resistance Museum in Amsterdam. The matchbox is marked in Swedish, but Swedish matches were sold in Holland for many years..
Scott

Okay .... so, borrowing Joe's siggy-pic (becuz it was handy!)



is this a DD because it has an idler-wheel?

Thanks for educating me, Jim!

And, Joe, I agree.... great pics!

-whatever

-Lou

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5 out of 4 people have difficulty with fractions.

bigfun & Scarface...


never underestimate the power of Google!

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"This Guy Fawkes bloke, do we let him off or what?"

Lou mate, the 'idler' is the wheel at the opposite end of the track to the toothed drive wheel. It usually spins freely on it's axle as a handy place to hang the track on. Most all tanks have them.

The DD Sherman's ran their propellers off the idler wheel, hence they're of a slightly different form to usual.

The one's with the large scoops aren't 'DD' vehicles, they are 'just' prepared for deep wading.

DD refers to this 'Duplex Drive', running on land by track and in water by propellers. They're the ones with the big pop-up canvas sides that form a boat of sorts, designed by the rather brilliant Hungarian born engineer Nicholas Straussler. Unlike the mere wading kit (scoops) that allows the machine to run in a few feet of water without swamping it's engine or exhausts, the DD Sherman, Valentine, and Tetrarch trial model could swim properly in deep water.

Cheers,
Adam.

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It's only the Internet.

Thanks Adam.

Lou,

Here is the layout:

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Glad to know my sig was of use.

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"This Guy Fawkes bloke, do we let him off or what?"

It was handy at the moment. Sorry.

Here are some more shots of the deep wading trunks. They were also used in the PTO for obvious reasons. The first shot is of a Sherman lying in a flooded shell hole on a Normandy beach. The other two are I believe on Tinian.

Enjoy.

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Thanks, guys. So, not to beat a dead horse, (but, hey, he's dead anyway!), then on the DD the engine drove the toothed drive wheel, which transferred power to the track, which turned the idler which was connected to the propeller shaft.

Which takes me back to some war movie or other that I remember seeing in the distant past, where there were some tracked vehicles approaching the beach (although they weren't DD's and it was in the Pacific), and their tracks were kicking uip a big froth and I remember wondering how spinning their tracks generated enough forward motion to propel the vehicle to the beach.

Now I know. Thanks, gents.

And, Joe, your siggy-pic was invaluable.

Feel free to use my TRR anytime!

-whatever

-Lou

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5 out of 4 people have difficulty with fractions.

I've got to get better at multi-tasking!!

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This is a pair of Dutch resistance crystal radios, built into a small metal can, and a matchbox. The image is from a postcard bought at a Dutch Resistance Museum in Amsterdam. The matchbox is marked in Swedish, but Swedish matches were sold in Holland for many years..
Scott

Lou,

Check out this site:

Google Image Result for http://members.shaw.ca/junobeach/images/juno-7%20sherman%20dd%20tank%20drawing.jpg

Go to the bottom

Lou,

What you probably saw were LVT's like these. They are tracked landing craft and some versions had light tank turrets mounted. Look at the design of the tracks. They were indeed designed to propel the vehicle through the water.

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So.... the DD's propellers were geared to the engine, instead of the convoluted drive train that I enumerated above.

OK.

Thanks