Sherman And Pershing Co-drivers

Why are they there and what specifically do they do?

They were known as BOGs or bow gunners. Presumably, they could also serve as relief drivers on long road marches, but they were mainly there to serve the hull machine gun. On the tank destroyers, which lacked a hull machine gun, they operated the radio, as there was no place to mount one in the turret.


Well I do know that in the M8 Stuart/Scott the loader rode in the co-driver’s seat. (The vehicle was so small they needed the extra space in the turret when on the march.) Also there were most likely dual steering laterals on the co-driver’s side so in an emergency he could take over steering in the Stuart chassis. (In the M5 Stuart chassis the dual overhead steering laterals were such an easy, standard design it would almost be more work to leave them out for the M8 co-driver than to just build it like every other Stuart from M5 on.)

I imagine the M10’s and Jackson’s were the same as to tight spaces. The loader told to sit his butt down in the co-driver’s seat to make more room for everyone else in the turret.

In M4-based vehicles there was only one driver, with only one set of controls. The co-driver was bow MG and/or radio operator. This post was eliminated in Firefly tanks where his seat was replaced with ammo storage.

The M26 was different, as the co-driver got his own set of auxiliary controls, so he could driver or operate the bow MG as needed.

Generally deleting a crewman meant spreading extra maintenance tasks on the remaining crew, so wasn’t a popular idea. But in WW2 they were always struggling to get enough men so maybe the right-hand seat might be free - but the loader would struggle to reach that seat with the turret pointed forward, and had better be at his station if things got hot!

1 Like

I did not say on the M4 ~ the dual control scheme was limited to only the M5 Stuart chassis production.

And the loader comments were only pointed at the M8 SPG.

I tried to make that clear in my statements above but perhaps I did not succeed.

p.s. Having actually worked inside several M5’s I can attest that the seat back on the co-driver’s side was totally removable to allow for somewhat easier entrance to that position.

Hi Mike,

No offence meant! I know almost nothing about M5/M8s! I was just addressing M4s and M26s because those I know…

What strikes me as odd is how they briefly went dual-control with the M26 and the various T-series heavies, but by the time the M47 came out they went back to only one set of controls. That despite the M47 having all the necessary hardware to put the joystick, brake, and other bits on either or both sides! I wonder if having two drivers was a bit counterproductive in emergencies…

No offense taken.

So the codriver isn’t necessarily one. And when you think about it, why would extra controls be needed when they serve no real purpose and only add to the expense and complexity of a tank?

Yeah, it seems a bit specific to have dual controls in the event of the driver getting hit while the rest of the tank remains operational. But then there’s the helicopter theory - they need two pilots because it takes twice as much wishful thinking to get them flying… :grin:

There’s a risk of creating an incorrect doctrinal understanding by trying to compare tanks and tank destroyers in WWII US Army use. Keep in mind that tank destroyers were designed, their employment doctrine was created, and their crews were trained by the artillery branch, not the armored branch of service.

There were no “bow gunners” in tank destroyers (except for the M36B which was an accidental coincidence because of the M4 tank origins of the hull) for the same reason that the tank destroyers also didn’t have coaxial turret MG’s. The artillery basically considered these AFVs as self-propelled anti-tank guns with minimal armored protection. The crewman located next to the driver was a radio operator.

(Consider and compare this doctrinal thinking to that of the WWII Germans and their StuG III which was also an AFV designed and developed by their artillery branch to provide an infantry support cannon under armor. The later employment of the StuG as a “substitute” tank mirrors the similar use by US commanders of US tank destroyers as “substitute” tanks. The different industrial circumstances between the two armies resulted in a more formalized adoption and incorporation of the StuG into regular armored formations. However, the underlying doctrines at the start of the war illustrate that armored warfare, to include how to counter it with anti-tank weapons, was still developing worldwide, even in the much-vaunted German army of Blitzkrieg fame.)

The tank “bow gunner” in tanks was primarily a machine gunner who had additional duties (like all the other crewmen). In command tank, he functioned as a radio operator who was (supposed) to be able to use voice and Morse code AM. However, tanks had a different combat mission than tank destroyers, and both hull and turret machine guns were considered essential for the performance of that mission. (By many studies, tanks often engaged more targets using machine guns than with their main guns.)

Tanks and tank destroyers were designed and crewed to perform two doctrinally different tactical missions, so their crew members did not have directly comparable jobs or training.

These doctrinal missions overlapped in actual combat practice, and this overlap ultimately resulted in the demise of the tank destroyer branch (and the tank destroyer, itself). In practice, commanders having tactical control of attached tank destroyers generally employed them as if they were tanks demonstrating that what was really needed for combined arms operations was more tanks (and not a mix of tanks and not-tanks).

Evolution of the tactics and doctrine of the armored branch also caused changes in the crew size of tanks. The fundamental realization was that a combination of infantry and tanks was almost always the best solution, therefore, in close combat situations (where the bow gun might have been used) infantry MGs were usually more effective, but in open combat situation, the more stable and elevated turret coaxial MGs on the tanks served to engage longer ranged targets.

This doctrinal change occurred at about the same time as the concept of the “main battle tank” (or “universal tank” in British parlance) began to replace the fielding of “light, medium, and heavy” tanks (or “light, cruiser, and infantry” tanks). Therefore, postwar tank designs quickly eliminated the second hull crewman and the bow MG. (It’s interesting to note that the Soviets initially included fixed, hull MGs in their proto-T54 designs - the T44 - but quickly dropped those.)

(The short-lived flirtation with super heavy tanks, like the M103, the Conquer, the T28 and the Tortoise was ended as advances in the sciences of metallurgy and propellant chemistry enabled the design and fielding of 100-105mm tank guns that were more effective than the 105-120mm guns that used two-part ammo with enormous propellant loads. These advances also coincided with improved aiming and ranging technologies.)

1 Like