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--- guides:land_nav [2017/04/21 15:49]
thendash added compass section
+++ guides:land_nav [2017/04/21 16:48]
thendash added resection, modified resection, and polar coordinates sections
@@ Line 68: / Line 68: @@
 **Reading a grid**
-{{ :guides:gridref.png?direct&300|Click to view full size}}
+{{ :guides:gridref.png?direct&250|Click to view full size}}
 It is easy to read 2, 4, and 6 digit grid references from the ARMA map because the map scales as you zoom in and out, but you can read a
@@ Line 95: / Line 95: @@
 ===== EQUIPMENT =====
 ==== COMPASS ====
-{{ :guides:compass.png?direct&300|Click to view full size}}
+{{ :guides:compass.png?direct&250|Click to view full size}}
 The compass is a tool used to measure direction. The version modeled in ARMA is a lensatic compass with both degree and milliradian
@@ Line 114: / Line 114: @@
 ===== NAVIGATION TECHNIQUES =====
+==== BEARING ====
+Technically //azimuth// is the proper term, but the term //bearing// is commonly used to refer to the direction to an object or location
+in relation to magnetic North.
+In ARMA we do not need to worry about the difference between magnetic bearings measured with a compass, and grid bearings measured on the
+map.
+**Taking a Bearing**
+To measure a bearing from your current location to a visible object:
+  - Line up the //sighting wire// on your compass with the object
+  - Read the bearing in degrees where the //index line// intersects with the //inner ring.//
+**Back Bearing**
+A back bearing is the opposite direction of a bearing. It is commonly required for use during land navigation.
+To convert a bearing into a back bearing:
+  * **Add 180 degrees** if the bearing is **180 degrees or less**
+  * **Subtract 180 degrees** if the bearing is **180 degrees or greater**
+==== LOCATION ====
+**INTERSECTION**
+{{ :guides:intersection.png?direct&250|Click to view full size}}
+Intersection is the **location of an unknown point** by successively occupying at least two known positions on the ground and then map
+sighting on the unknown location. It is not often used in ARMA, but can be used to locate the position of an otherwise inaccessible
+location.
+**Steps:**
+  - Measure the direction to the target from known location 1.
+  - Draw the bearing from known location 1.
+  - Move, or communicate with someone at a different known location.
+  - Measure the direction to the target from known location 2.
+  - Draw the bearing from the known location 2.
+  - (Optional)Repeat from subsequent known locations as desired.
+  - The intersection of the drawn bearings is the location of the target.
+**RESECTION**
+{{ :guides:resection.png?direct&250|Click to view full size}}
+Resection is the method of locating your **own position** using at least two well defined locations that can be pinpointed on the map.
+The more locations available, the more accurately you can locate your position.
+**Steps:**
+  - Identify two or thee known distant locations and mark them on the map as accurately as possible.
+  - Take a bearing to location 1.
+  - Convert the bearing into a back bearing.
+  - Draw the back bearing from location 1 on the map.
+  - Repeat for other locations.
+  - The intersection of the drawn bearings is your location.
+**MODIFIED RESECTION**
+Modified resection is the method of locating your **own position** when you are located on a linear feature, such as a road or stream.
+It is easier and quicker than regular resection as it only requires one bearing to be taken.
+**Steps:**
+  - Identify a known distant location and mark it on the map as accurately as possible.
+  - Take a bearing to the location.
+  - Convert the bearing into a back bearing.
+  - Draw the back bearing from the location on the map, stopping when it intersects with the linear feature at your location.
+  - The point where the drawn bearing meets the linear feature is your location.
+**POLAR COORDINATES**
+Polar coordinates is a method of locating an **unknown position** from a known position using direction and distance to the target.
+It is often used in ARMA for locating targets for artillery.
+**Steps:**
+  - Take a bearing to the target.
+  - Estimate/Determine distance to the target.
+  - Draw the bearing from your location on the map.
+  - Measure the determined range on the drawn bearing.
+  - The range on the drawn bearing is the location of the target.