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Hello,

here's a question from the (French) webmaster of the website "Tanks on Tarawa" :
http://www.tanksontarawa.com/

Do you know where I could find a drawing that shows what can be seen from the interior of a Sherman tank, through the periscopes and vision devices, particularly in the close neighborhood of the tank? What are the blind spots?

thanks

P-O

In general terms, any tank buttoned up has an extremely limited field of view for all positions, even the commander with his vision block ring (if one is provided in the first place.

The driver and co-driver will have one periscope (at best) or one limited direct vision hole (in some later war vehicles). Anything closer than ten feet has been invisible in any of the vehicles that I have been in with periscopes. The vision to the front is limited by the field of view of the vision devices - with direct vision, the view to the ffront is limited in the extreme.

The gunner on virtually every post-1939 tank is blind as a bat - he might have one periscope with a fixed view to the front, blind to within fifteen to twenty feet of the vehicle. Loaders occasionally have periscopes, with a similarly restricted view (but possibly traversable).

The commander's position is often ringed by a series of vision blocks or periscopes. I've had limited experience with other vehicles (paricularly as the vision devices are usually a wreck), but I've spent a lot of time in the cupola of M48 and M60 vehicles. The "Vista Vision" ring on an M48 was barely adequate, and with substantial blind spots to the left and the rear and the front. The vision ports on the cupola were pretty much worthless, and the sighting periscope limited to front only (wherever the cupola was trained). On the M60, things were pretty much the same, although I found the cupola vision to be a bit better.

Both of these modern vehicles also had an optical rangefinder for the commander's use. Again, a very limited field of view, only in the direction of the main gun, and in this case well away from the vehicle.

The long and the short of it is that armored vehicles are virtually blind when buttoned up. In RVN, we spent perhaps 99% of the time open. Of course, we didn't face much of an anti-tank potential, but even if we did I imagine that I would have done the same.

What Terry said. Just by way of illustration (though I know you've been inside any number of vehicles), here is a fairly typical view of the world through a vision block on a far from pristine armored vehicle (in this case, an M113 ACAV in VN that hasn't seen a car wash lately, though I did wipe these down from time-to-time). I have no idea what prompted me to take this photo, but here you are.....keep in mind there are ~six of these arrayed around the cupola of an M113). This is pretty much what you'd see in any given direction on an M48 or M60, on which I also have service time. On those vehicles, the driver would have three, if no IR viewer was in place (and one reason why TC's communicate with their drivers). I'll venture a guess that up close, a viewer through a prismatic vision block can see about 45 degrees of arc.

Also, as Terry said, gunners don't see much of their world...only the part that concerns them.

www.vhpamuseum.org/11t...ewslit.jpg

Gentlemen,
thank you for your replies. PO, thanks for posting my question on the forum. I forgot about it.

Anyway, the vision from inside a medium tank (as well as many other tanks) is very limited.
Like Ed Gilbert (author of Marine Tank Battles series of book) says; the vision from inside a tank, is like if you drive your car with toilet paper rolls on your eyes!

Romain C.

The simplest way of describing the field of view would be to measure the distance between the driver's eyeballs and the vision blocks. Then the height above ground. Do some math and angles, and lay out adhesive tape of the appropriate shape on the windshield of a vehicle. Then try to drive around the block safely.

- Maple_Leaf_Eh

The simplest way of describing the field of view would be to measure the distance between the driver's eyeballs and the vision blocks. Then the height above ground. Do some math and angles, and lay out adhesive tape of the appropriate shape on the windshield of a vehicle. Then try to drive around the block safely.

Perhaps that advice might be to do that with eyeglasses and walking on foot?

The practical answer to the question is that anywhere within about 2m of the vehicle, and below 1.5 m in height, would be almost invisible. It's one of the reasons we tell the infantry to stay back, and it's the same reason we refer to infantry as "crunchies". The theory is that your wingman is there to clear away any pests that might turn up closer that that.

The driver has the best view of the ground ahead, but usually can't see anything closer than 2-3m in front. It means that a good driver must be looking well ahead of his current location and planning his turns in advance. We laugh when we see tanks hanging with one track off of a railcar or bridge, or we see tanks beneath a bridge, but that's what happens when your driver loses his sense of position because he can't where his tracks are hitting the ground.

The blind spot is much wider for the TC, out to 10-15m, depending on the vehicle. The turret tends to block the view in most directions, so the blind spot gets bigger.

The loader, if he has a view of anything, is generally restricted to a view looking through a periscope, about the size of a mail slot. Even when his periscope is movable, his views are at best distant, and often only suited to being an air guard.

The gunner looks forward through his sights. In most cases, and certainly in modern AFVs, his only view is where the gun is pointed, and the ground comes into view 75-100m in front of the vehicle.

There is a good reason tankers really don't like fighting 'buttoned up'!

Chuck

maybe these will help, from a WWII german anti tank manual