All You Need is a Mirror and Sunlight!
- Stretch an arm in front of you, at eye level.
- Extend the index finger and middle finger upwards to form an upright “V”.
- Use the gap in the “V” like a site; place the object you wish to signal in line with the sighting “V”.
- Hold the mirror with the opposite hand off to one side of your head, at head-level.
- Catch sunlight with the mirror to form a sunspot from the mirror onto the ground or a nearby object.
- Raise the sunspot to your “V” fingers, and move it back and forth across the “V”, with the target object still in the site.
- The target object should see your flashes.
Experiment With Different Reflective Objects
The above technique works best with a compass sighting mirror, or any specialized, commercial or military signal mirror. It also works, to lesser degrees, with any object that will reflect sunlight. Try using a watch crystal, cell phone screen, knife blade, and similar objects.
Experiment with different target objects around you, which forces you to use different mirror-to-sun angles to achieve a sunspot.
Practice With Caution
Practice the above technique with co-workers or acquaintances on the ground under controlled conditions. Do Not practice on aircraft or vehicles! The flashes are bright and can be blinding.
During an actual emergency, when signalling aircraft, cease signalling when the aircraft passes overhead and clearly acknowledges it has recognized your position. The flashes may impair the pilot or air crew’s vision.