How to Use an E6B Flight Computer

The E6B flight computer has been the main slide rule for computing all aspects of pre-flight and in flight data critical to flight operations since before World War II. Although technology has made advancements in handheld electronic computers, most pilots still rely on the E6B for fast, reliable calculations they can trust. Heavy transport pilots even carry these dependable units.

Instructions

1. Turn the computer, commonly called the whiz wheel, over to the wind or course correction side. This is the side with the semi transparent center. The reason for this side is to do course and air speed corrections (due to wind speed and direction).

2. Notice the heading to the destination. For purposes of this article, we will use a heading of 360 degree with the wind out of the Southwest at 220 degrees at 20mph.

3. Spin the center of the E6B computer to set the wind direction under the arrow at the top. Align one of the line on the slide rule with the hole in the center of the computer.

4. Mark the wind speed up vertically from the small hole in the center (with a pencil). Count the speed lines to determine where the mark goes. Turn the center of the computer so the heading of 360 degrees is under the arrow at the top.

5. Slide the rule up or down using the pencil mark. Put this mark on the corresponding true air speed line. For true corrected heading, count the degrees of correction necessary to compensate for wind drift and which way to correct and subtract form the intended heading. In this case, the aircraft would be drifting to the right if not corrected.

6. Look at the speed under the small hole in the center---this is the actual ground speed. Since there is a tailwind, the ground speed will be faster than the indicated speed.

7. Examine the movable logic side. Notice that there are instructions for most of the not-so-obvious functions The E6B computer will do mathematical calculations, conversions from MPH to KPH, degrees Fahrenheit to Celsius conversions, and will hold a constant number so that a variable can be calculated.

8. Look the scales over for the instructions for the different functions that are too many to cover in entirety. There is also an instructional book that comes with the computer and when learning to fly, the instructor will take approximately three to four hours to instruct in its use. En route calculations as to corrected altitude and airspeed, weight and balance calculations, wind course corrections, ground speed, fuel consumption, time en route, rate of decent versus distance and time inbound, and many more calculations are part of the E6B's capabilities. Study this tool as one of the most important items in your flight kit.