1. PURPOSE.

a. This manual is designed to aid counterbattery and other artillery intelligence person-nel. Combat experience has proven that the system and techniques presented herein will assist materially in:

(1) Speedy location and silencing of active enemy batteries.

(2) Ready identification of enemy artillery and mortars by caliber and type from shell fragments.

b. The methods described in this manual comprise one of the basic means of obtaining information of the existence and location of enemy weapons. These methods are used almost invariably in connection with one or more of the sources of counterbattery infor-mation. The principal sources are:

(1) Crater analysis and fragment identification (via shellreps).

(2) Interpretation of air photos.

(3) Field artillery observation battalions (sound and flash).

(4) Air observers ( air OP's) and ground observers.

(5) Interrogation of prisoners of war and friendly civilians.

c. Crater analysis and shelling reports (shellreps) are used to check and verify battery locations obtained by these other means. Also these other sources are used to verify in-formation from shelling reports and crater analysis.

2. IMPORTANCE.

a. Speedy location and identification of enemy artillery and mortars are of paramount importance in combat. Unceasing effort and all possible means and methods must be employed to provide promptly the information necessary to knock out such enemy wea-pons. This mission and the gathering of information essential to its accomplishment are of vital interest to all soldiers.

b. Information of the location, mass, disposition, and zones of fire, by caliber and type, of the enemy artillery, mortar, and rocket weapons is of great value in estimating enemy tactical capabilities. The success of an entire operation depends to a considerable ex-tent upon the accuracy, completeness, and timelines of this information.

c. Systematic examination of craters and shell fragments may disclose information about new types of enemy ammunition and weapons, a knowledge of which may permit us to develop early and effective counter measures. This knowledge may also suggest improvements in our own ammuntiion and weapons.