DogDodger

8 hours ago, Collimatrix said:

The ability to make wider radii turns at higher speed would be nice, but a Sherman driver could approximate a wider-radius turn by using the turning brakes intermittently (and in fact they were instructed to do so to save wear).  So there would definitely be some speed range where the Sherman could simply initiate a turn, but a Panther would have to slow down to downshift into third or lower.

Exactly, and that's what the writer of that report was trying to get across. He goes on to detail what a PITA it is to have to estimate the radius of the turn "sufficiently far in advance to permit the vehicle's speed to drop low enough so that the desired low gear can be engaged, and has the further disadvantage that the vehicle's forward speed may be slower than is necessary or is desirable." So if you drop a guy into the Panther and send him off in a race, the writer implies there's a good chance he'll take the turns too slowly since he isn't familiar with the steering system.

2 hours ago, Xlucine said:

Didn't the french find the panther broke after 150km, not 1500?

 

Panther was better than sherman at swimming uphill through mud, but churchill was dominate in poor conditions. Tigger was just hopeless, for some reason, and T14 (!) was about the same as the sherman

https://imgur.com/a/fV825TZ

Great report. We always have to be careful in the first place with these types of singleton tests, though, I suppose. In Mr. Churchill's Tank Fletcher details how the British 1st Armoured Division staged a trial between the Churchill and Sherman in December 1943 during which the tanks would "climb a scrub covered slope of average gradient, traverse the side of a hill which was cut up by small wadis and then tackle a very steep hill." The tankers reported that while Churchill could tackle difficult terrain slightly faster, the test was a draw: "There was no obstacle which the Churchill surmounted that proved impossible to the Sherman on the day of the trial." The trial was repeated after a rainstorm, and again the results between the tanks were similar: "Neither the Churchill nor the Sherman managed to get more than one third of the way along the course and both broke tracks when mud got into the drive sprockets and under the tracks." The Sherman reportedly got stuck and towed out of its mire by the Churchill, but the Churchill's final drive broke when driving on the wet plowed ground. Flecther states that driver skill would be more of a factor in mobility than the two tanks themselves.

1 hour ago, heretic88 said:

 

Still, the Panther in the swedish tests was damn impressive. It didnt appear to be underpowered at all. Sure, the Sherman in the test was an earlier variant, with narrower tracks, but I dont think even an M4A3E8 could beat the Panther in any of those tests. Equal at best. And Im pretty sure that the apparent inferiority of the Panther in curved courses was caused by the inexperience of the drivers. Putting an M60 driver in the seat of the T-72 would produce similar results.

I'd largely agree.

Thanks for the reference; I have that book. Good info, but I felt at times the writing was almost being deliberately padded to meet a word count or something.

Anyway, the Greens say that with the 2500 rpm governor the HL230P30 only made 580 hp, which would give us 12.8 hp/ton for the Ausf.G, which is less than the M4A3E8 (which was the Sherman the Panther was compared to during the speed test where the tracks sank 1" into the ground and individual Shermans were faster/slower) but still more than the diesel version. The report the Greens quote about the curvy course had the Panther compared to an M4A1, and the report seems to be blaming the Panther's steering system, not any ground interaction factors per se: "Except for the ability of the tank to make a pivot turn about its own axis, its steering system does not contribute to satisfactory maneuverability and this tank, even though it has a higher top speed than a medium tank M4A1, could not keep up with the medium tank on a course where curves were frequent. It is readily realized that practice in operating these vehicles would contribute greatly to driver skill and, therefore, increased mobility..." The US Army drivers were apparently unused to a steering system where one had to anticipate matching the transmission gear to the radius of the turn, which would add considerable difficulty I would think. The Greens also quote LTC Wilson M. Hawkins from a later report: "It has been claimed that our tank is the more maneuverable. In recent rests we put a captured Mark V against all models of our own. The German tank was the faster, both across country and on the highway and it could make sharper turns. It was also the better hill climber." The Greens conclude: "In the case of the Panther tank, its tactical mobility surpassed the Sherman tank and that of the T-34 tank series." So even with the governed engine the Panther's power:weight doesn't seem too bad, and the comparison with the M4A1 on the curvy course may have been an aberration due to a combination of lack of driver skill and the higher requirements the Panther's designers imposed on its operators?

1 hour ago, Collimatrix said:

Only in vertical obstacle climbing.  In US Army testing, Panthers were almost exactly equal to M4A2E8 Shermans on muddy terrain in terms of straight-line speed (the report notes individual tanks doing slightly better or worse), and noticeably inferior in cumulative speed on curved courses.

And the reasons why aren't mysterious at all.  Panthers are heavier than Shermans, but they have lower mean maximum ground pressure than Shermans (even with the wider tracks), but grossly inferior power to weight ratios.  In the particular test conditions where the US Army tested their tanks, these two factors cancelled out.  If you knew the precise gearing ratios, rolling resistance and cohesion of the soils you could predict this mathematically.

 

Is this report available online? Sounds very interesting; thanks!

Did the report say the M4A2E8 had a better power to weight ratio than the Panther, though? If we take the 45,400 kg Panther Ausf.G, which is the heaviest, with its 700 hp/1340 lb-ft HL230P30, we get 15.4 hp/29.5 lb-ft per metric ton. I don't have the weight for the M4A2(76)W HVSS handy, but the M4A2(76)W weighed 73,400 lb. If we use the lighter single-pin T66 tracks, HVSS would add 2950 lb, giving us a tank that weighed 76,350 lb, or 34,630 kg. The GM 6046 produced 410 gross hp and 885 gross lb-ft. So the M4A2E8 would make ~11.8 hp and ~25.6 lb-ft per metric ton. Even if we use the lighter and more powerful 74,200 lb (33,700 kg) M4A3(76)W HVSS with its 500 hp/1040 lb-ft GAA, we still only get 14.8 hp per ton, but the torque is a bit higher at 30.9 lb-ft.

Wow, training is getting more realistic all the time.

The engine doors and exhaust pipes have definitely been changed, fwiw.

Could be. Pacific Car & Foundry also mounted travel locks on their M4A1s starting in August 1943. PacCar tanks had a rounded rear lower hull plate, but the video's low resolution and the modifications to the tank are making it unclear to my eyes.

Jeeps, very sorry but I somehow missed this post. I hadn't mentioned it or posted pictures because I was making a joke about the car I had just gotten, although to be honest its name was probably upwards of 20% of the reason I was interested in it... Anyway, since we're on the subject and since you'd probably be among the handful of people who would have any chance of appreciating the license plate I ordered for this German M4, here's a picture. Apologies for the off-topic post, but didn't want you to think I had been ignoring you and rest assured if I did somehow manage to buy an actual tank I'd be posting everywhere about it! Now back to actual tanks.

Why don't you knock it off with them negative waves? That's a mother beautiful tank!

6 hours ago, Bronezhilet said:

Since no one got this (or even tried),

 

That one took some digging, but I believe it ended up being the proposed howitzer version of the Canadian APC named after this guy:

.

Stansell and Laughling say, "At CDA [Chrysler Defense Arsenal], the glacis [applique] armor was first installed in early August 1943. The exact date of the introduction of the side plates is not known, but CDA's M4 composites starting [sic] getting theirs in late August 1943. It's safe to assume that they were installing them on the M4A4 line at the same time. It's also interesting to speculate that some M4A4s left the factory with front applique only." And later, "Once a vehicle was issued to troops--either stateside or overseas--it was rarely modified. Most, if not all, applique appears to have been installed by the factories or by the tank depots before issue or during a remanufacturing program." Chrysler rebuilt 1610 M4A4s destined for the British by October 1944, so it seems from their research that it might be rare for the applique armor kits to have been installed in Britain. On the other hand, if Chrysler started adding the applique armor in August 1943, over a year of M4A4 production had already elapsed, and 6173 M4A4s had been produced by the end of the second quarter of 1943, which would leave potentially 4563 tanks that were built before the applique armor was added to the factory line and which also didn't get run through the remanufacturing program. So bottom line: who knows?

On 6/26/2018 at 12:24 AM, Sgt.Squarehead said:

 

It's levitating above the track return skids.....Badly at the rear! 

Maybe it's turning right.

That's the machine that was formerly at Aberdeen.

3 hours ago, Walter_Sobchak said:

 

Hmm, its obviously M60ish.  

Correct.

3 hours ago, Scolopax said:

It's in a museum though instead of space.

Also correct.

18 minutes ago, Walter_Sobchak said:

 

Yep, it looks like the back of the M60A2 turret.  Is this one of the prototypes that now sits in a museum?

You got it. It's in the American Armoured [sic] Foundation Tank Museum in Danville, VA. I tried to hide the vehicle beside it since it's kind of iconic.

Would a picture like this work with the rules? I can edit if it's against the spirit of the thread.

One of the LOSAT prototypes. :)

Pedantically, Stansell and Laughlin assert that Pressed Steel manufactured "21 examples of the 76mm HVSS [M4A2] in the second quarter of 1945." But Fisher made upwards of 68% of M4A2s of all types, so Soviet tankers would have at least a very good chance of seeing vehicles from this factory.

Yikes. It took me a while to work through the confusion while going through the article:

• But that picture is a Sherman, not an M7 tank.
• But the M7 tank was an International Harvester product, not ALCO.
• But the M7 tank was armed with the 75 mm gun M3, not a 105 mm gun.
• But that picture is of a howitzer motor carri...oh.

Nice work! Cameos were made, lol. I'll be there again this year.

12 hours ago, Jagdika said:

 

Fake M26 Pershings, M4 Shermans and Type 97 medium tank. These fake Type 97s' chassis come from SU-76 SPG.

 

 

These look similar to the vehicles used in the movie Assembly, which is available subtitled on Youtube. I enjoyed the film overall, and thought they did a pretty credible job with the tanks, to be honest.

On 2/27/2018 at 11:22 AM, EnsignExpendable said:

All the documents I found in the Canadian archives refer to them as "the old group" rather than "gang". The TOGs don't come up a lot, but there is one instance where the TOG2 is considered alongside the A30 as a heavy gun carrier, although it is quickly discarded. 

Hills does make it sound like certain important Canadians were interested, and "Group" does indeed replace "Gang" in some Canadian reports. Brigadier F.F. Worthington "had in fact not only attended the firing trial in Lincoln of the TOG-2 turret, but was the first man to fire the 20cwt. AA gun in the turret." A Canadian Colonel F.F. Fulton wrote a report on 30 April 1943 recommending the hydraulic drive system of TOG-1 see further development as it allowed the vehicle to be steered with "phenomenal ease." There are other mentions of Canadian thoughts in the book, but it is maddeningly unindexed, and Canadian reports are something I didn't make my own pagination notes on.

Oh wow it's too bad I just bought an M4 today.

I saw The Tanks of TOG by Andrew Hills thanks to a blurb on Walter's blog, and finished it a couple days ago. It was a much more sympathetic review of the program, and of Sir Albert Stern in particular, than I had been expecting, and therefore provided an interesting perspective. Both Fletcher in The Great Tank Scandal and Beale in Death by Design report that Stern got "The Old Gang" of WW1 tank designers together on his own volition, and they then thrust themselves upon the War Office with meddling and wasteful efforts. Smithers in Rude Mechanicals and Chamberlain and Ellis in British and American Tanks of World War Two posit that Stern et al were first approached by the War Office, whose specifications then they worked toward. Hills agrees with the latter two, saying the original rhomboid turretless TOG was not what the designers wanted, but what the War Office had demanded after work on a turreted tank had already begun. The travails of The Old Gang are reported in great detail, as well as the creation and modifications to the TOG tanks themselves. Assertions that Ricardo had a powerful diesel engine ready for manufacture, and that the TOG designs could have been the most heavily armored and armed British tanks to take the field (with, for example, the 17 pounder or more powerful guns and armor eclipsing the heavy Churchills) years ahead of the Centurion or Challenger--or even before the Churchill was reliable enough to not require an apology letter from Vauxhalls going out with every example--were certainly intriguing. Hills alleges that personality conflicts played a great role in the stymieing of TOG, and while this charge may be a bit overhyped, the work and designs that The Old Gang came up with do seem impressive compared with the contemporary state of British tank development, and also seem strangely ignored when projects like the A33 assault tank were floundering.

The editing could use some work, as there were instances of repeating paragraphs, confusing sentence structures, and ideas restated shortly after their introduction, but overall I consider this a worthwhile read.

1 hour ago, Conner Webb said:

the Gavin

Great. Now my eye's twitching again.

I haven't heard of one. Not that that should be taken as definitive, of course.

7 hours ago, Jeeps_Guns_Tanks said:

Hey @DogDodger,  do you know anyplace I can get my grubby paws on those reports?

Sure. You can get the first book as a pdf here. The General Board reports are available here; Tank Gunnery is number 53.