Calculators

Calculators #

E6B Flight Calculator #

  • E6-B the most common, also known as a “dead reckoning computer”
  • Front side: Slide rule (most usage)
  • Back side: Wind correction
  1. Plotter (sectional and WAC scales)
  2. Rotating scale (what you input data with)
  3. Temperature conversion chart
  4. ??? string attachment
  5. Sliding chart for determining wind correction
  6. Rotating dial and pencil friendly writing surface for determining wind correction

What you’ll be using it for #

  1. Fuel, time and distance calculations (multiplacation and division)
  2. Wind correction (finding crab angle and ground speed), trigonometry
  3. Other - Finding TAS, Density Altitude, converting units, etc.

Fuel, Time and Distance Calculations #

Scales #

  • Scale A: Input and reference data with pointers (like buttons on a calculator). WHere you will read ALL variables except time.
  • Scale B: Read time in minutes or seconds
  • Scale C: Determine time in hours

Pointers #

The “input” method of the E6B. Different pointers will give you outputs in different units or bases.

  • Multiplication and division pointer: Extends from the center of the “10” in a black box
  • Second pointer: Little pointer above the “E” in seconds allows you to work with seconds.
  • Minute/Hour pointer: Most commonly used poitner on the E6B. Allows you to work in minutes and hours to do anything in base 60.

Multiplying #

  • 22 x 35 = 770
  • The small “10” is the multiplication. Put it on the first number you want to multiply (22) and then look at where the second number (35) is. You’ll then get your final (770).

Example:

  • Calculate 650fpm & 7min:
  • You’ll put your E6B “10” to 65, and then look at where “70” is.
  • It will be “45.5”. So it’s 4550ft gained.

Division #

  • 15 / 3 = 5

Move both numbers together (15 outside numerator, 30 inside denominator)

You need to descend 5,000ft in 7 minutes, what descent rate will you need:

  • Larger number will be 50, smaller is 70. Looking at 10 (multiplier number thingy) it’s at 71.5, therefore it’s 715fpm
  • 5000ft / 7m = 715fpm

Leg time (time between 2 points at a given ground speed) #

  • Time is throught of in seconds, mins and hours, rather than 1.33hours, it’s 1:20. Base 60 system and the e6b has a minute/hour pointer and second pointer for that.
  • Think if it’s going to take hours, minutes or seconds to get there and use that particular scale.

In minutes:

Here’s a problem: At 110kts ground speed, how long will it take you to travel between two checkpoints that are 18nm apart:

  • Use minute/hour pointer: point at ground speed (11)
  • Find distance on Scale A (18)
  • Read answer off of Scale B directly across from the distance (9.8minutes, it’s between the 90 and 10 numbers.. so it’s 9.8 minutes).

IMPORTANT: Remember the “magnititude!” it may be confusing, but if you ever get confused, read between the two numbers. Example… assume it’d be in minutes since it’s 110kts for 18nm. The result is between 9 and 10. So it’ll be 9.X minutes, this example it’s 9.8 minutes.

Calculating for leg hours (another example). You’ll use the INNER ring.

In hours:

How long will it take to fly 320nm at a ground speed of 120kts? Assume hours for output…

  • “Pointer” is at 12
  • Look at “32” on inner
  • Look below to 2:40 (1st notch between 2:30 and 3:00)
  • Which means 2:40hours. (2 hours, 40 minutes)

In seconds:

If you suspect it will be in seconds, use the SECOND pointer (the small one that says seconds beside it) for calculation.

How long will it take to fly 1.2nm at 140kts?

  • SECOND pointer at “14”
  • Look at “12” for leg distance which would be 1.2nm
  • Look at inner number (it’s at 31).

Working in reverse to find ground speed and distance.

Ground speed: Align distance you’ve traveled on Scale A, with the time you’ve traveled on either Scale B for minutes or Scale C for hours. Read your groundspeed of the pointer Distance: Align pointer with the groundspeed. Find time on Scale B for mintues or Scale C for hours. Follow the time directly to Scale A to get the distance traveled.

Fuel for a given leg #

Like finding time, the pointer and scales you use will be different if you are working with seconds, minutes or hours.

How much fuel will a 152 burn on an 8 minute leg with a fuel burn of 5.3 GPH?

  • 5.3GPH: Point to “53” on outer ring
  • 8 minutes: Look at “80”
  • Look above for number, which is 71 (0.71gallons)

Crab Angle and Groundspeed Adjusted for Wind #

Calculating: True airspeed of 125kts True course of 70 Winds from 290 @ 22kts

First rotation: 0. 100: Put the “hole” in the middle over 100 for easy calculations

  1. 290: Make the dial to your wind direction (290)
  2. 22kts: Mark the 22kts of wind to 122 (ex. mark it at 122 for 22kts)

Second rotation: 3. 70: Rotate top to your true course (70) under true index 4. 125: Slide the “pencil mark” to your air speed 5. 141: The ground speed is actually 141kts on the “hole”. 6. Find the wind correction by counting the lines from center line which would be left correction of -6degrees.

If it falls LEFT of the center line, you subtract the value. If it falls right, you add the value.

After all that, you have a groundspeed of 141kts and a true course of 64 degrees.

TAS (True airspeed) and Density Altitude #

  • PA: Pressure altitude
  • OAT: Outside air temperature
  • CAS: Calibrated airspeed

For this example:

  • PA: 15,000ft
  • OAT: -30c
  • CAS: 150kts
  1. On rightmost, align the air temperature (-30c) with pressure altitude (15)
  2. Look at Density Altitude you’ll see that DA is 13,000
  3. Look at CAS 150kts on the B Scale. Directly across you’ll get the TAS (on the A scale) which is 184kts

In total you’ll get 13,000' and 184kts.

Conversions #