Book: FM 23-91: Mortar Gunnery
I recently found this US Army FM (Field Manual) and since I read it, here is a quick overview. Oh… Just for your information, regardless of the below image, the content is about the “1 March 2000” edition of the manual.
Title: Field Manual No. 23-91: Mortar Gunnery
Author: Headquarters, Department of the Army
Part One: Introduction and Fundamentals of Mortar Gunnery
Chapter 1: Introduction
This is a general introduction dealing with concepts like the mission of mortar platoon, teams and procedures, etc.
Chapter 2: Fundamentals of Mortar Gunnery
Another introduction chapter that goes through various information about subjects such as ranges, vertical interval, distribution of bursts, muzzle velocities, ammunition etc. This is a large chapter with useful information about the equipment and techniques involved in mortar gunnery.
Part Two: Fire Direction Center
Chapter 3: Introduction
This is the starting chapter of the second part of the manual. Here, the reader can learn about the principles of fire direction, team duties, etc. Its a very small introduction chapter that leads to the next chapter.
Chapter 4: Major Concerns of the Fire Direction Center
Continuing from chapter five, this one dives into the details of fire direction center. Starting with the types of sheaves, it moves to angle T, ballistic meteorological message and corrections, and other specific topics providing extensive details and examples on each subject.
Chapter 5: Call for Fire
Here we go through all the details involved when a call for fire message is involved. Everything from identification to description, methods of engagement, authentication, etc. are discussed in this chapter.
Part Three: Mortar Ballistic Computer
Chapter 6: Introduction
And here is the third part dealing with the details of mortar ballistic computer systems. Beginning with identification of the various switches, it moves to audio alarm, capabilities, memory characteristics and error messages to end this introduction and get into more details in the upcoming chapters.
Chapter 7: Preparation of Fire Control Equipment
Here you can find the different types of data entries that the mortar ballistic computer can process and how to use each one of them. Of course, it goes through each data entry, discussing how to use it with mortar ballistic computer.
Chapter 8: Type of Missions
All the supported mission types are explained in this chapter. Everything from naming, switches, operator’s manual, etc. about mission types are available in this chapter.
Chapter 9: Special Procedures
Here more advanced concepts are identified. Ranging from registration and sheaf adjustment, to immediate smoke and immediate suppression. It’s a very detailed and informative chapter.
Chapter 10: Digital Message Device Supported
This is the last chapter of this part and deals with mortar ballistic computer’s (MBC) abilities for digital communications. Its a compact operator’s communication manual.
Part Four: M16 and M19 Plotting Boards
Chapter 11: Introduction
This new part is about the two classic plotting boards to do mortar gunnery calculations by hand. This chapter introduces the reader to the two boards and how to use them.
Chapter 12: Preparation of Fire Control Equipment
Based on the knowledge from the previous chapter, this one goes into the details of the three supported (by M16 and M19 plotting boards) firing charts which are observed firing charts, modified-observed firing charts and surveyed firing charts. In all cases, the manual provides extensive details and examples.
Chapter 13: Types of Missions
Similarly to the MBC’s mission types, this one discusses the plotting boards’ supported mission types. For each scenario it goes through the various concepts and examples required to understand the procedures and techniques involved in each case.
Chapter 14: Special Considerations
The last chapter is about special procedures when using plotting boards for effectively engaging targets. Its a nice chapter with very detailed examples.
First of all, I have to admit that I was very impressed by the similarities of this US Army field manual and the equivalent one from the Greek Army. They are almost the same. Now to the content, like most FMs, it is simple, compact and gives all the information you need to know for each subject. Anyway, if you are interested in mortar gunnery it is a good reading.