# Presentation: 590932

## Field Expedient Direction Finding

- Field Expedient Direction Finding

- Developed by the
- National Emergency Services Academy

## Objectives

- Learn various methods to determine direction without the use of a compass
- Stick and shadow method
- Watch method
- Sun
- Stars
- Natural

## Stick and Shadow

- The sun rises in the east and sets in the west- but not quite...
- Rarely does the sun rise directly in the those directions (90 or 270 degrees)
- You can still use the shadow tip method to determine direction
- Start by finding a stick you can drive in or prop up on the ground.

## Place a stick or branch in the ground at a level spot where a distinctive shadow will be cast. 

- Shadow Tip Continued

- Mark the shadow tip with a stone, twig, or other means. This first shadow mark is always west.

## Shadow Tip Continued

- Wait 10 to 15 minutes until the shadow tip moves a few inches. Mark the new position of the shadow tip in the same way as the first.

- This second shadow mark is always east. Draw a straight line through the two shadow- tip marks to obtain an approximate west- east line.

## Shadow Tip Continued

-     Now, to determine your north- south line, stand with the first mark (west) to your left. The other directions are north to the front, east to the right, and south behind you.

- Remember- the stick must be vertical in the ground.

## Tell time with your shadow?

- The west part of the east-west line is 0600 hours and the east part is 1800 hours.  The north-south line becomes noon and the shadow of the stick becomes the hour hand.

## Shadow Tip Continued

- Accuracy varies depending on latitude and time of day
- Early morning and late evening are the least accurate; Close to noon is the most accurate
- The closer you are to the equator- the more accurate
- If readings are taken throughout the day, errors tend to cancel each other out

## Watch Method

- Must have a non-digital watch
- Not as accurate as shadow stick method

- In the northern hemisphere:
- Hold the watch with the hour hand pointing to the sun
- Imagine a line running through the 12 and true south is midway between the hour hand and the 12.

## Star Method

- At night, you can find north by locating the North Star, Polaris. First, find the big dipper.  The last two stars of the dipper’s cup point directly at Polaris about 5 times the distance between those two stars.  Facing Polaris, you are looking north with east on your right and west on your left.

## Slide 11

## Other Clues...

- Not precise- and it takes practice, but...
- Plants generally grow towards the sun
- Moss often grows on the side away from the sun or on the damper side of the tree but can be influenced by other factors
- Leaves on trees usually thicker on the sunny side
- The rings of a tree stump are usually closer together on the side closest to the poles

**Notes:**
The old saying about using moss on a tree to indicate north is not
accurate because moss grows completely around some trees. Actually, growth
 is more lush on the side of the tree facing the south in the
Northern Hemisphere and vice versa in the Southern Hemisphere. If
there are several felled trees around for comparison, look at the stumps.
 Growth is more vigorous on the side toward the equator and the tree growth
 rings will be more widely spaced. On the other hand, the tree
growth rings will be closer together on the side toward the poles.
Wind direction may be helpful in some instances where there are
 prevailing directions and you know what they are.
Recognizing the differences between vegetation and moisture patterns
on north- and south-facing slopes can aid in determining direction. In
the northern hemisphere, north-facing slopes receive less sun than
south-facing slopes and are therefore cooler and damper. In the summer, 
north-facing slopes retain patches of snow. In the winter, the trees
and open areas on south-facing slopes are the first to lose their snow,
and ground snowpack is shallower.

## Make Shift Compass

- A needle from a sewing kit can be fashioned into a makeshift compass

- Magnetize the needle by rubbing it with silk or a magnet
- Hang with a thread to let the needle point to magnetic north
- You could also float it on some cork or similar material

**Notes:**
You can construct a more elaborate improvised compass using a sewing
needle or thin metallic object, a nonmetallic container (for example, a
plastic dip container), its lid with the center cut out and waterproofed,
and the silver tip from a pen. To construct this compass, take an ordinary 
sewing needle and break in half. One half will form your direction
pointer and the other will act as the pivot point. Push the portion used
as the pivot point through the bottom center of your container; this por-tion
should be flush on the bottom and not interfere with the lid. Attach
the center of the other portion (the pointer) of the needle on the pen’s
silver tip using glue, tree sap, or melted plastic. Magnetize one end of the
 pointer and rest it on the pivot point.

## These presentations were made by the National Emergency Services Academy for the purpose of advancing, refreshing, or reviewing information for search and rescue training.

Products shown are for illustration purposes only.  The National Emergency Services Academy, Civil Air Patrol, or the United States Air Force does not endorse, guarantee, or recommend any specific company, service, business, or product.

Presentations are designed to be used with qualified instructors familiar with your local area.

- Products shown are for illustration purposes only.  The National Emergency Services Academy, Civil Air Patrol, or the United States Air Force does not endorse, guarantee, or recommend any specific company, service, business, or product.
- Presentations are designed to be used with qualified instructors familiar with your local area.

## QUESTIONS? 

**THINK SAFETY!**