Welcome back to the military vehicle technology foundation
and our tour, part 2, of an early model m4a1.
Ok it's a Grizzly, but who's keeping track?
Now the first thing you'll notice as you're looking at the turret
is that there is no loader's hatch,
which is what you might call a surprising omission.
In fact the reaction is "what on earth were they thinking?"
Now in fairness of them they're still learning,
and if you look at the M3 medium, that didn't have
a loader's hatch either, but it was a smaller turret.
The problem of course, you can imagine.
If you've got to get out of the tank in a hurry
for some reason like, I don't know, the tank is on fire,
it's a bit difficult if you don't have a hatch of your own.
What is perhaps less excusable was
it took a year and a half of production,
and about a year's worth of combat experience
before somebody finally figured out how to drill a hole
in the roof of the turret and install a hatch.
These started coming off the production lines October 43.
Now, there was a retrofit kit put out,
so if you're in the field and you had a no-hatch Sherman,
you could get this kit that would come,
it will tell you make a hole here in the turret roof
and install this hatch
the loaders became much happier,
but still it was a surprising omission.
Also surprising was that the idea didn't die.
If you look at the Merkava IV, the Israeli tank,
the early models of that
looks like they did not come with loaders hatch.
Doubtless is proved unpopular as evidenced by the fact
that after a very brief period of time the tank started appearing
with loaders hatches It's a structural weakness
but you have got to give the crew a chance.
Other features around the turret.
Speaking of hatches, this is not the original hatch
that came with an early 75-millimeter tank.
It was the originally the split hatch.
Simply two pieces of simple metal that came up,
there would be a single rotating periscope
in one of them and that's how you would see out.
Very unsatisfactory.
It also had a mount for the calibre 50 on the ring.
Now, what turned out happened was that the vision cupola
was the same diameter as that of the split hatch
so it's actually very easy to take vision cupola
and put in place of the split hatch and all of a sudden you have
a much, much better hatch.
So for example this one now has an azimuth ring
if you needed it for some reason
as well as the periscope.
A simple, easy, hatch to come down.
The split hatches kept going quite a way through the war
they did start installing springs
to make them easier to open in the middle of '43.
Still, the Grizzlies as near as we can tell,
all came out with originally the split hatch design.
There was also the British vision cupola,
which was a very good design
but obviously the Americans didn't use it.
As we move further round
pick up the mounting point for the calibre 50
which has now been moved back and left.
The machine gun, of course, could only be fired
really by somebody at standing on the back deck
so not really useful for the crew.
This is a rest for the barrel
so the gun will be resting forward and horizontally this way.
Latch it out of the way, put it down, and you can see
the spotlight that could be controlled from within the tank,
the loader had a handle, or it could be discounted
and hand held in a pistol grip that the commander has.
If we move forward, we see the commander has vane site.
This is used simply to gauge direction
as he's telling the gunner to spin onto a target
he knows roughly which way the gunner is looking.
Speaking of the gun you'll see that there are
very large screws at the front.
This was done for modularity.
The idea was that you could turn the tank
into pretty much any required configuration
by simply swapping out the gun.
Undo the bolts and install module A, module B.
Not in the field. Once it left the factory.
the idea was it was the same thing,
but you could very easily swap it out on the production line,
and these would be anything from the 57-millimeter, 75 the 105,
or they were hoping for the three-inch.
Didn't work out,
we'll come back to that story at a future point.
That's pretty much the outside of the turret roof
so let's go inside.
I have moved inside to where the commander would be seated.
I'm on a fold down seat:
A very simple, lift latch, fold down.
If I wanted to be seated with my head out
there is actually an additional platform down here
which I have folded it out of the way.
It is cozy in here.
The breech recoil guard is taking up a lot of my space
and I've had to place one leg on either side of the gunner's seat.
Not a good start.
Controls, as he's going around.
Well he's going to have an override handle here,
push forward for left-back for right,
and all this is a simple physical cable
that goes all the way down and moves the Gunners control handle,
which then moves the rest of the system.
Very useful for getting your gunner
on to target quickly, you don't have to yell at them
to go and left, right, hey you missed it,
you've gone too far, your other left.
I'm sure you're familiar with that, some of you.
As you start moving around underneath is a pistol grip
for the spotlight so you would dismount it
from the position on the front of the turret
and put it on here and you can wave it around
and see whatever it is you need seeing.
To see out, speaking of seeing, the six vision blocks
on the direct vision cupola.
So again, early thanks did not have this vision cupola,
they had the simple split hatch which comes down
with the periscope in the middle of it.
This is far better.
Not ideal by modern standards but by world war two standards,
this was one of the best cupolas you were going to get.
As we move around to the back we see… rations.
Packaged by Patent food products, Chattanooga, Tennessee.
Ration type K.
Use as a waterproof container for matches, cigarettes and other items.
For security, hide the empty cannon wrappers
so they cannot be seen.
I'm in a 40 ton tank or, thirty-five ton tank
and I'm worrying about seeing wrappers.
The radio behind him is either an SCR 508 528 or 538,
all things depending and this is a 20 frequency set.
You can listen on 20 and speak on 10.
They are selectable.
Your program, you spend your time ahead of time,
programming your crystals and then use the push buttons
to select whichever frequency it is that you want to transmit on or monitor.
Pretty similar to the way we have things today.
That's pretty much it for the commander's seat,
and next I'm going to move forward to the gunner.
While we're here let's talk elephants again,
and that means the gun.
75mm M3 was familiar from the m3 medium.
It wasn't a low-velocity gun,
it wasn't really a high-velocity gun,
it was sort of in the middle, general purpose,
but still one of the best things that the Americans had at the time.
In fact since it was developed from the 1897 gun
which was mounted on the m3 half-track,
the tank destroyer of the time,
and you end up with the surprising-to-some situation
that the Sherman actually had a better gun to the tank destroyer.
Marginally, but there you go.
That's another long story you'll see in my videos,
but yes, tanks were supposed to kill tanks.
Now by this point of the war the Americans had started
solving a lot of ammunition problems
that they had had with the m3 medium.
So at this point now you have armor-piercing high-explosive,
you have shot, you have high explosive,
you have smoke/white phosphorus.
All very useful.
The AP round, the m61, that was rated for about
three point six inches at muzzle of RHA,
or four inches of face hardened under Navy criteria.
This in practice meant that although you can knock out
a Panzer 3 or a Panzer 4, if you can hit it,
pretty much at any range,
unless you got a good flank shot on a Tiger or,
at least a reasonable shot on a Panther,
the best you could do would just be
to batter it into submission, which in all fairness,
actually happened with surprising frequency.
Anyway that was the end of the options for the Americans.
They did try in August 1941 starting a program
to mount a 3-inch high-velocity cannon.
However, the gun was just too big, too heavy.
Solution B was to take the 76 millimeter which just been developed,
found on the M18 Hellcat, and put that in here.
So they stuck it in, it worked, Ordnance signs off on it, hooray,
and an order of a thousand was made and to be ready
for the invasion of North Africa in late 1942.
This was all well and good until Armored force actually got ahold
of one of the prototypes and they took a look,
and said, no we don't want it, it is too cramped,
it is too inefficient, the sights aren't good,
yadda yadda.
So they nixed it and they told them to try again,
and it ended up being the T23 turret
which I hope to come across again in some future episode.
On a late-model Sherman.
Two exceptions did happen.
One was the British that stuffed the 17-pounder into this.
You know, it's cramped enough in here with the 75,
I can't imagine what they thought of the 17 pounder,
especially if they thought the 76 was bad.
The other was after the war,
under the MDAP program,
the Americans refitted some of these tanks
with 76 millimeter guns anyway, and gave them to Allies.
And crew efficiency be damned, they were going to get these tanks.
They wanted some tanks.
The most famous of these can be found
in the movie Kelly's Heroes. You look at them,
they're 76mm Shermans with the small turrets.
The loudspeakers are optional. So that's about enough on the guns
we're going to come back to that probably as I say,
in a future Sherman episode, assuming I can find one,
and the meantime let's move on to the controls.
Now the gunner's seat itself is actually quite comfortable.
My left foot is comfortably resting on the two-foot triggers,
my right foot a little bit underneath the manual traverse,
but it's protected by the skeletonized turret basket rim
so it stops my feet from getting crushed
as turret traverses.
Under power traverse, control, of course, being done here,
a full circle would be about 24 seconds.
If you wished you could go to a manual Traverse mode,
you can see it is now disconnected,
by pushing down on this release lever.
You now go into an actual manual transmission
which is fairly quick.
Let's go back up.
Elevation: of course you have the manual elevation control option here,
reasonably quick, but better yet,
just like on the m3
you can disconnect the elevation gear
and now your gun is very well balanced
and can be used in a stabilized mode.
And why would you do this?
Well, obviously so that you can get the target
into your sights quicker as you're moving cross country.
Speaking of sights, originally the only one
that came with the tank was the periscopic one
through the turret roof.
It was Periscope, M4, with Telescope M38,
and as you can see there's the wide field of vision
on the left side, and when you have your target
more or less in the middle you can then look with your right eye
through the telescope, which is a x1.4
and has a reticle in it. Fantastic.
Now, why would you do this as opposed to having
a direct vision scope such as this one?
Well, there are a couple of reasons.
Firstly, it allows you to have that really wide field of vision
which is very important for acquiring the target.
He who sees the enemy first
will probably shoot first and will probably win.
The other advantage
is that if your sight is going through the roof,
you can spot the enemy without exposing your turret.
So you can stay hidden, keep an eye out,
and away you go.
However, there was a couple of problems as well.
The linkages between the periscope and the gun,
which has been unfortunately removed on this,
they weren't the most reliable, and it took a field modification
to come out that really kept the sights aligned.
In the long run the solution was to install
a direct vision scope as well.
This was originally the M55, it wasn't well-received,
they updated it to the M70F.
Now, this gave you is some additional capability.
Firstly it was a x3 optic instead of the x1.4,
so arguably this would become the primary site de facto.
But imagine what this does now for your engagement speed.
If you're in a turret-down position,
in ambush waiting for the enemy to show up,
you can be scanning around looking with your periscope.
You see a target, you lay on it,
you're in stabilized mode. But you're still behind the berm,
you cannot engage the target because if you press 'fire'
you're going to hit the dirt right in front of you.
"Driver, move out." You then move your head
to the direct vision sight, with the stabilizer engaged,
as soon as the gun has cleared the berm that you're hiding behind,
the hillcrest, whatever, "driver stop."
you are already on the target.
It's in your sights because of the stabilizer system.
You now know that you have just cleared the berm,
so you can shoot quickly, take the shot,
probably fire a second shot, fall back behind cover,
return to your wide view optic and start the process over again.
This was a level of capability
that no other tank had in the world in 1942, 1943.
Ok, 43 by the time you had these things in.
Indeed it was pretty much unique through to until the Korean War.
Centurion finally came along.
Other things in the gunner's compartment.
Well, you've got the rheostat for the stabilizer system,
there's an azimuth indicator down here for indirect fire,
so this will give you the line of bearing horizontally;
for elevation you would use the gunner's quadrant
and simply place it onto the breech-block.
Other than that, this is a comfortable position.
Very ergonomically well designed,
the gunner can get the most out of this tank.
That done, let's go on to what I'm going to assume
is slightly less pleasant, the loader's.
As you come over to the loader's side,
there's bad news and good news.
The bad news, I've already mentioned:
The lack of a hatch. In order to get here
had to come under the recoil guard and I can only assume
things get more difficult if the gun is in elevation.
Fortunately in depression it gets much better
and I think that if your tank is knocked out,
it's probably more likely the direction will be in.
The good news though is once you're in here,
it's actually very roomy.
I am sitting on his seat, it's not annoying at all,
there's ventilation up here and I have visibility
through the rotating and elevation-adjustable periscope.
2-inch smoke bomb thrower is to his left.
Originally this was a British request,
the Americans eventually got in.
There used to be a pistol port back here.
Now this was deleted in April of 43, it wasn't deemed necessary.
The crews objected to this, they deemed it was necessary
and so later on in production the pistol port
was added back in again after a brief absence.
Ammunition:
Ninety seven rounds of 75 millimeter were available to him
and it was stowed pretty much all around the tank.
The sequence of events for taking the ammunition
was firstly you took it from the ammo box under the gun
then it will be the front-right sponson
and then it will be underneath the turret
then it will be the right rear sponson…
and the idea was that the two or three rounds
that were actually in clips..
there's no clips here but there would be,
they were extreme emergency only.
The default was that you were going to take it out of the box
and that was deemed to be fast enough.
You may question whether or not that is true,
well actually it's not that bad.
So if you'll bear with me for a moment while I demonstrate,
and you will note
I am doing all this from the seated position.
Come down, you lift up the ammo bin lid,
so you probably do this once at the beginning of the action.
Once that's out of the way
you lift up the etaining clips of the ammunition
so I now have four rounds easily available to me.
Lean down, grab the round, I now have a 75 millimeter round.
Place it into the breach which is closed on this tank
so I can't actually do it,
and then throw the round all the way into the gun.
Now again this is…
I can't remember the last time I was in a world war two tank like this
and I could load the gun all eight ready rounds,
plus the ones in the clips, so maybe ten rounds,
from the seated position. This is wonderful.
If only they had thought to put a damned door in the turret.
They actually are called doors, and we call them hatches by default,
but technically they're doors.
Also technically, the loader is known as the cannoneer,
although I've never ever met anybody who refers to the loader
as a cannoneer in routine operation.
4700 rounds of caliber 30 would be fitted.
Of course, the caliber 30, coaxial to the main gun here
and he has his control up here for the spotlight
that we talked about earlier.
That's pretty much it for the loader's side,
this would be a wonderful position to be in after October of 43.
Otherwise, the "oh my god the tank is on fire" test
I think immediately from this is going to fail.
And move to the front of the hull, the driver's position.
I am now in the up position, so I can drive open hatch
easily enough, and of course,
the seat will move down
to a much more reasonable position for driving with the hatch closed.
Alright, so this hatch unfortunately is not complete,
it is not going to lock all the way down,
but you can get a general idea of the situation.
So my left foot, of course, is going to be on the clutch.
It's a reasonably heavy clutch, unfortunately, on this particular tank.
I've seen other tanks that the club very light,
so it seems to be a matter of, well, just how much is the tank used.
I've driven Shermans before, trust me, this is not normal.
He has two optics to look out of.
Firstly, he has the traditional
rotating adjustable elevation directly in front.
Should something happen to this
he can move to an auxiliary further forward,
but that doesn't rotate or elevate at all.
For controls, the traditional two tillers
and if you pull back, there is a rocker down here
which engages and disengages the ratchets which also turn it
into the parking brake. So pull back both tillers,
pull up on the rocker
the parking brake has now been engaged…
and now disengaged.
Accelerator, low on the right, not a problem there, fuel pump.
Gear shift is now to its right.
If you remember on the M3 medium, the driver sat astride the gearbox.
No longer, on the m4.
So he has quite a simple system,
your traditional manual transmission on the right.
No particular issues there.
You do see also they have here
the windshield for the driver,
so if he's driving in a low threat environment
but it's wet or something like that, he puts up this drivers hood
which gives him protection from the wind and the rain.
Very nice, it even comes with a windshield wiper
to keep the rain off.
The control panel on the left
this is pretty much typical
with the light switch on the fair left-.
Fuel cut-off is how you turn off the engine,
the magnetos are left, right, or both.
and of course you would boost and start.
This control mechanism really doesn't change
throughout most of the Army's tanks from the 1930s to the 1950s.
In fact you still see headlight switches
still more or less the same today.
Auxiliary fuel pump, when you need it,
and your additional normal array of amperes,
voltmeter, rpms, tops out at 3,500 you see there is no red line.
There should be a red line because it shouldn't really go,
if I recall, over 2,800, but there is no red line.
Miles an hour, goes up to 80. There's optimism.
Temperature gauge low oil pressure light,
and of course, circuit breakers.
This is an easy vehicle to drive.
The fact you don't need to double clutch is very nice.
It's not quite as good as an automatic transmission,
but if you've got to have manual, and I do like driving manuals,
this is a lot of fun.
That is pretty much
everything I'm going to say about the driver's side,
I will now move over to bow gunner.
Moving over the bow gunner, and the first thing I will note
is that the hatch actually works on this
so it's easily enough locked into place
by using this screw system, no particular problems there.
We'll come back to that.
His primary toy is the Browning 1919A4
in a simple ball mount.
To aim it, he simply follows his tracers
by use the periscope, either the rotating elevating one
in the bow gunner's hatch, or the fixed one further forward.
I note that there's a couple of spare periscopes
mounted around as well of course, should they get shot up.
The utility of the bow machine gun is questionable.
It looks like it was retained simply because
when the tank was moving, it was the most accurate system
on the tank, if you didn't have a stabilizer,
and the stabilizer I've gone into before.
The stabilizer actually worked very well
if you happened to be a member of the crew
who know how to use it. Unfortunately,
it was so secret they didn't teach anybody
how to use it. Go figure.
Other parts around the tank.
There is ammunition stowed on the right here,
behind this little plate.
Further forward where we now have a storage compartment,
would otherwise go an SCR 506 radio
if this was a command tank in American service.
Now, down at my feet is one of your big indicators
of a Grizzly versus an American-produced Sherman.
It is a small hatch which is designed
for deploying the snake anti-mine system.
Don't ask me what it is but that is what it is for.
The Canadian tanks had this, the American ones did not.
There is a proper escape hatch further to the rear
and as far as escape hatches go at the period,
it's not small. It's a reasonable size.
Compared to, say the Matilda from earlier,
or even the T-34, this is something
you can probably get out of even if you're wearing winter kit,
so point there.
The transmission oil is checked down here
through this little filler port
and that's pretty much it.
There remains one more test
this is again the small hatch Sherman.
Now, the thing about Sherman's is
although they have a reputation of being death traps, they weren't.
On average, the Americans found they lost
maybe point 6 of a person per killed tank
and the survivability rating of this tank
is higher than pretty much any other tank on the battlefield
per knocked out tank,
and part of the reason for it is once they fixed
the loader's hatch issue, which I think I mentioned before,
getting out of the Sherman is really, really easy.
And bear in mind this is the small hatch Sherman
so I will try the "oh bugger, the tank is on fire" test
with a small hatch Sherman and we'll let's see how I do.
Now one last point I'll note before I conduct the test
is that there is a minor cheat.
In 1943 they started issuing spring kits.
Before that, in the tank to open up the doors,
you were fighting against the full weight of the hatch.
However, come 43 someone decided "let's put springs on it"
and make it much easier to open and get out,
and this is one of these retro fitted tanks.
Of course, off the production lines they were added as well.
So, without further ado,
oh bugger the tank is on fire.
Try doing that in a T-34 or a Comet. Won't work.
So now I'm out, let's close up.
Firstly, a note on names.
It is of course well known that the British,
specifically Churchill,
came up with the name Sherman for the tank.
However, it wasn't until late nineteen forty-four
that US Army Ordnance finally decided
to give it a name of General Sherman.
The troops fighting on the front lines didn't really care
what US Army Ordnance thought the tank should be named,
and they just continued to call it the medium, or the m4,
It wasn't until after the war that the name Sherman
began in American parlance
to be commonly associated with the M4 Medium.
When it came out in 1942 this is arguably
the best tank in the world, however
there were a couple of glitches.
the turret hatches, the optics were the main ones.
Still, by 1943 they had started fixing these
and it really was an excellent tank.
You can argue best, not best, but it was definitely very good.
Technology progress quickly, however.
What was world-leading in 1942 was much less so in 1944.
Fortunately, by this point
the improved Shermans were coming off the production line
and there were entirely different beasts.
I do hope to do one of these in a future episode,
so we'll come back to that then.
About 33,000 of the tanks were made
plus an additional 4600 with 105 howitzer.
Of these about half of them went to the UK
and an additional 2,000 went to the Soviets.
That's not bad for a country that in five years prior to the war
had only built a hundred medium tanks.
That was the m4a1 medium, We'll see on the next one.
Right proudly high over Dublin town the hung out the flag of war.
'Twas better to die 'neath an Irish sky
than at Sulva or sud-el-bar.
And from the plains of Royal Meath
strong men came hurrying through.
While Britannia's huns with their long-range guns
sailed in through the foggy dew…
And unfortunately we are short for time
so we'd better get back to work.
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