Arrow Speed Chronograph Pro

This chronograph measures the average speed of an arrow shot from a bow to a target using sound.

Also works with paint ball guns with velocities under 400 ft/s.

Reports the speed of your arrow after release, similar to a standard radar chronograph. It also reports the speed of your arrow at common shooting distances down range. It reports the energy of the arrow at any distance down range, as well as suggested size of game for hunting. It reports the deceleration, or drag, of your arrow as well. Several different arrows may be recorded for comparison.

Wind speed and temperature are the most significant factors affecting the speed of sound.

Temperature accounts for altitude. Humidity and barometric pressure are negligible.

The speed of sound is needed to adjust for the time sound takes to travel from the target back to the microphone after the arrow hits the target.

Select nearest wind speed by moving right side view of windsock up or down. Trees in the display will move, helping to estimate wind speed.
10 mph ( 5 m/s, 15 kph): Leaves and small twigs in constant motion
20 mph (10 m/s, 40 kph): Moderate branches move, small trees sway
30 mph (15 m/s, 50 kph): Large branches to whole trees in motion
Enter wind direction relative to shot by rotating the windsock in the top view on the right side

Select nearest temperature in degrees
Select distance to the target in yards (or meters)
Select delay time, the time it takes to put your cell phone in your pocket, draw your bow, and aim.
Select duration, the time it takes to release the arrow after hearing the single chirp signal
plus the time for the arrow to travel to the target and the time for sound to travel from the
target back to you. Use 4 seconds for long distance shots, otherwise use 2 seconds.

Press , put phone in shirt pocket, nock arrow, draw bow, aim, and wait for 3 chirps, 2 chirps, 1 chirp, then release arrow as soon as you are ready, within half a second or so.

The button will change to other status messages when active, and can be pressed again at any time to cancel.
A blue sound signal will appear with a mark showing when the bow shot and when the
arrow hit the target. The velocity of the arrow will be reported in the box.
Press to listen for the shot and the arrow. Shoot again if the sounds were missed.
If you entered the wrong temperature, wind speed, or distance before you shot, make the changes, then
Press to update the speed calculation.

Press tab button to hide user interface. Press again to show user interface.

Supports English or Metric units.

No velocity will appear after a shot if sounds were missed from the arrow release or the arrow hitting the target. Try to limit noise during the shot.
Make sure the microphone is sticking out of your shirt pocket.
Try not to aim at a shot-out part of your bag target, or pin up a milk carton, so the arrow makes a louder sound when hitting the target.

On the Shot tab, select the round button under Arrow. An Arrow selection box should appear next the the Arrow Button. Click the Arrows tab at the top, then click + under the grid to add an arrow. Enter a new arrow name, if desired. Enter weight of arrow in grains (or milligrams) to provide kinetic energy values. Return to the Shoot tab and make sure the correct arrow is selected in the Arrow box.
Now shoot an arrow. The Save button should appear next to the speed. Click Save if the shot was good. Now shoot at different distances.

Review all shots under the Arrows tab by selecting the tab with the name of the arrow and then Shots. Shots may be deleted by pressing the x at the end of the corresponding row. Shots at the same distances are averaged.
Click the Speeds tab to view detailed information about arrow.

Program has been tested out to 100 yards in 20 mph winds on a bag target, with arrow speeds > 360 fps.

Program works with cross-bows, recurves, compound bows, and paint ball guns.