Periscope (Self-Propelled Vehicle)

TM 9-258

d. The head assembly contains a 90ƒ prism for

windows provide a seal against the entrance of dust and

moisture. Crosslines are etched on the horizontal

directing the forward line of sight through the window of

windows for rough sighting in observation.

the body assembly. The body assembly contains the

c. The periscope is supported in either a

aforementioned window and another 90 prism that

viewing or a retracted position in a periscope holder

displays the field of view to the driver. This periscope

which is secured to the body of the vehicle. The holder

provides a 500 horizontal and 140 vertical field of view.

permits rotation of the periscope in elevation and

azimuth.

8-16.

Periscope (Tank).

d. This periscope is 11 inches long, 6 1/2

a. The periscope illustrated in figure 8-18 is a

inches wide, 3-1/8 inches in thickness, and has an offset

monocular-type optical sighting instrument that serves as

of 8-7/8 inches.

the main component in the fire control system of the

machinegun on the tank.

8-15.

Periscope (Self-Propelled Vehicle).

a. The periscope illustrated in figure 8-17 is a

unity-power daylight viewing device employed by the

driver of the vehicle. Three periscope stations are

provided within a notable armored hatch which afford the

driver the maximum of safety and vision of the terrain

during tactical maneuvers.

Figure 8-18. Periscope (Tank)- assembled view

Figure 8-17. Periscope (Self-Propelled

Vehicle)assembled view.

b. The eyepiece of the periscope, which

b. Each periscope consists of two separate

contains the eyelens, center lens and field lens (fig 8-19)

units, a head assembly and a body assembly. Both are

is fixed and remains stationary relative to the vehicle.

coupled together by a common mount.

The prism rotates the line of sight from 15ƒ depression to

c. Two 90ƒ prisms and an optical instrument

60ƒ elevation in maintaining the line of sight parallel to

window (fig 8-16) comprise the optical components of

this periscope.

the line of fire of the machinegun throughout the gun's

full range. Connection from the gun to the periscope is

made

8-13