British view of german SPG vehicles, Part 2: Jagdpanzer 38(t), the stand-in for StuG
Design born of necessity
Design of Jagdpanzer 38(t) was sparked by the ever increasing threat of allied bomber campaign, which targetted Alkett in October-November 1943, forcing Germans to disperse the production to Falkensee and Spandau,[1] and it effectively stopped the production in Alkett for many months to come.[2] Alternatives were chosen, one of them was to restart the Sturmgeschutz IV project, the other was to assemble StuG IIIs in BMM factory in Prague, however, there was a significant problem. BMM had no cranes with enough lifting capacity to handle the 24-ton Assault Guns. As a solution, in December 1943, a design for new Assault Gun was started, based on automotive parts of Panzer 38(t) and Panzer 38(t) neuer Art (New type). Specification called for a 13-ton vehicle, with frontal armor proof against most anti-tank guns. But the side armor was only to be proof against 7.92 mm machinegun fire and artillery fragments, and it was to be produced from SM (Siemens-Marteneit) low alloy steel. Wooden model was ready by the end of January 1944, and full production in BMM started in March 1944, joined by Skoda in July. Production vehicles weighted 16 tons, and were front heavy - 10 cm lower in the front. A total of 2650 of them were produced. [3] Let us look at what it was like to operate inside such a vehicle.
Packed like a can of sardines
British army surveyed a multitude of german vehicles after the war, one of them was the Jagdpanzer 38. Their opinion of the ergonomics and general comfort while operating were not very positive when it came to this vehicles. The report is divided by positions.
Commander is seated in a position 15 inches (38 cm) wide and 18 and half inch deep (47 cm) deep, first into the forward right side of the engine compartment. Atleast in this vehicles, his seat appeared to be padded, and was positioned 13 inches (33 cm) above the floor. The hull roof sloped above the commander's seat, at the forward end it is 3 feet 6 inches (107 cm) above the commander's head and ath the rear end 2 feet 11 inches (88 cm), there is no backrest and commander, when seated, cannot lean back because of a fire extinguisher behind his right shoulder. Roof above his head is padded, presumably to prevent injury when the vehicle is moving. When he is seated, his knees and feet project in front and below the deflector guard and can be hit by empty casings when the gun fires. Commander, when seated, cannot see through the scissor telescope, He was stuck with only two alternative methods of observation - either open the hatch and observe with his head and shoulders out, or if conditions did not permit that, observe through the telescope while crouching on the seat. This position was "most unsatisfactory and fatiguing" according to the test crew.
His vision devices were also rather unsatisfactory - a fixed periscope behind commander's head with a fixed view to the rear, which was too high if the commander was seated - he had great difficulty turning effectively to use it while crouching, and a scissor periscope, that could be used to only look to the left when the gun was at full depression.
In conclusion, Commander's position is considered to be completely unsatisfactory, with vision devices that could not be used effectively, very cramped, and extremely fatiguing if the commander would asume the crouching position. He was also in danger of being injured when the gun was fired.
Look into the commander's position.
Gunner is seated between the driver and the loader on the left side of the driving compartment. His seat is padded, but has no backrest or any other provisions, and can be adjusted only in height from 1 foot 3 inches (38,1 cm) to 1 foot 9 inches(53,3 cm).Whe the gunner is sitting erect in his seat, the sight is approximately 4 and half inches (11,5 cm) from his eyes, and if the gun is on center on left traverse, he has to lean over to the right to sight it. On the right traverse, the gun tends to push him off his seat, this position being very uncomfortable.
His gun controls - the elevating and traversing handwheels, lie in the same vertical plane, with the traversing wheel just below and slightly to the left of the elevating wheel. Thewheels controls the elevation of 10 degrees and the depression of 6 degrees, and the traverse of 4 degrees left and 5 degrees right. The elevating wheel is 9 and 1/4 of an inch (23,5 cm) wide and the traversin wheel is 9 inches (22,8 cm) in diameter. Handles on both handwheels point to the gunner and they are quite difficult to operate, since the handle on the elevating wheel is too short to offer adequate grip. Also, the loader's safety switch is on the left side of the deflector guard, where it strikes the guner's forearm as he operates the elevating wheel. The handles on both wheels, when they meet, are so close to each other that they can jam the gunner's fingers. As the firing switch is on the traversing handle, there is a danger that the jamming of the fingers between the handles will operate the switch and fire the gun. He can only sit and service both wheels comfortably with his knees apart and his right foot tucked under his seat. Any other position would result in his knees fouling with the traversing wheel.
When the gun is traverse 5 degrees to the right, it jams against the driver's seat, additional traverse can be obtained if the driver would stand up, turn and tilt his seat. Instead of a convoluted drill in an already cramped position, driver would probably just turn the vehicle, allowing the gunner to sight the gun within the area of unrestricted traverse when instructed.
His headset is plugged into a socket on his right, and wires hang between the elevating and traversing wheel, where they can become entangled. Gunner only has one vision device, the persicopic gunsight. The eyepiece rubber is too hard for comfort, and a narrow field of view probably makes finding targets from commander's directions problematic.
In conclusion, the gunner's position is very unsatisfactory. It is very cramped, gun controls are badly positioned, seat is insufficiently adjustable and has no backrest.
Gunner's controls.
Loader is seated in the left rear corner of the fighting compartment. Specifics of his seat are unknown, as it was not present in this vehicle. There is so little room between the loader and gunner that unless the loader works very slowly and carefully, he hits the gunner in the back every time he loads from rack A, and also with his shoulder or elbow as he rams the round in or operates his safety switch. As a result, gunner's eye might be knocked away from the sight at critical moments of action. His position is extremely cramped, and becomes even more so when gun is traversed to the right. At maximum right traverse, the loader is hemmed in between rack A and the deflector guard, and is unable to continue loading. The auxiliary MG 34 is mounted above the loader's position, The gun is difficult to control when the vehicle is on the move, and full 360 degrees traverse is prevented by some of the structures on the roof, for example, if his hatch is opened, it prevents 360 degrees traverse. His vision device, other than the machinegun sight, is a 4 inch (10 cm) wide episcope mounted on the roof to the left of his hatch. It faces left and therefore is not an adequate means of sighting.
In conclusion, again, his position is cramped and uncomfortable, especially on left traverse, when he is unable to perform his duties.
Ammunition stowage.
MG 34 controls.
Reloading trials.
Driver's seat is a metal frame with spring wire mesh laced through. A thin, hard padding curves upwards to the rear the backseat. The seat can be adjusted 3 inches (7,62 cm) backwards-forwards in three conditions, but the backrest is fixed and cannot be dropped to facilitate exit. Seat is arranged 3 inches (7,62 cm) to the right of the centre of the foot controls. There are two episcopes mounted in the glacis plate in front of the driver. The left episcope, one most used over rough country, is to the left of the centre of the seat. When the driver is leaning forward with his hands on the steering levers, his eyes are 2-3 inches (5,1-7,62 cm) away from the episcope. While leaning back, this distance increases to 10 inches (25,4 cm).
Driver's controls.
It was found that gearbox gave off considerable heat, although the weather was cold, and the driver was sweating profusely after only 15 minutes of driving.
There are no facilities for "opened-up" driving, driver must use the two eipiscopes provided for him, Each episcope mounted on the glacis is 4 inches (10,16 cm) wide, the total horizontal angle of vision provided by them is 42 degrees, with the eyes stationary. From the right episcope, the driver can see the ground from 27 feet (8,2 meters) in front of the vehicles, and from the left 14 feet (4,2 meters). These episcopes would provide reasonably good vision for the driver if his seat and controls would be repositioned.
The steering levers are easy to reach and operate, and are mounted horizontally. This is a good arrangement in a small vehicle, where vertical controls would occupy too much of the driver's legroom.
Gear changing is extremely difficult due to the high foot pressures required to operate the clutch pedal.
In the vehicle inspected, they were as follows:
The worst of all, when attempting to change from reverse gear, driver had to stand on the pedal, bracing his shoulders against the roof. Pedal itself is badly positioned, and the driver has to turn left and hold his left knee high and well bent to reach the pedal.
Driver's position is very unsatisfactory. His seat is badly positioned in relation to his controls, the gear changing controls are very hard to operate. The entire arrangement is very cramped and uncomfrotable, and if the vehicle is driven for longer periods, the conditions are so bad that they inevitably must create extreme fatigue and loss of efficiency in the driver.
It was not possible to estimate how much light there was inside, as there was no interior lighting fitted inside the vehicle studied. There are two hatches in the roof of the fighting compartment. The commander's hatch measures 2 feet 7 inches (79 cm) x 1 feet 1 and 1/2 inch (64 cm). Loader's hatch is 1 feet 5 inches (43 cm) x 1 feet 7 inches (48 cm). Loader's hatch cannnot be opened unless the MG 34 is traversed to 3 o'clock position. In case of major brew-up, on account of this hatch being used by 3 crewmembers, driver would probably not get out.
In conclusion, Jagdpanzer 38(t) is a very flawed vehicle, only notable positive feature were the low profile, fast loading times of the main gun, high ammunition stowage and close proximity of it to the loader, and no fumes from the externally mounted MG 34.[4]
[1] U.S. Strategic Bombing Survey: Tank Industry Report: 2nd Ed., Jan. 1947, pg.12-13.
[2] Bomb Damage to German War Production, Royal United Services Institution. Journal. pg. 169.
[3] Panzer tract No. 9, pg 9-2.
[4] WO 291/1307, Motion Studies of German SP equipments.pg. 9-21
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