Which method is NOT a recognized Call for Fire method?

The method identified as the correct answer refers to a non-standard approach in conducting a Call for Fire. In military operations, Calls for Fire are standardized requests for artillery or air support, and they generally adhere to specific formats to ensure clarity and effectiveness.

The Polar method involves an observer delivering coordinates based on a polar reference from their location, which allows for quick adjustments based on their position relative to the target. The Grid method typically involves using a set coordinate system, usually six-digit, to set precise targets on a map. Both of these are officially recognized techniques in military communications and target acquisition processes.

On the other hand, the term "Estimated" is not a recognized method for executing a Call for Fire. While observers may make estimates during targeting or observation, doing so does not conform to the structured and precise requirements outlined for Calls for Fire. Hence, calling it an "Estimated" method misrepresents the nature of the standard protocols in place, emphasizing accuracy and reliability over estimation. This distinction helps ensure that all personnel involved understand the communication and execution involved in artillery support, leading to effective and coordinated actions on the battlefield.