Your friend, Mr. E6B

1. Your friend, Mr. E6B

2. Resources • Jeppesen Private Pilot Manual • Chapter 8, Section C • Pilots Handbook of Aeronautical Knowledge • Chapter 14 pgs. 8 and 9 • ASA E6B Manual • http://www.asa2fly.com/files/support/E6B_Manual.pdf

3. Objectives • Learn the basic components of the Flight Computer • Gain a basic understanding on how to do basic problems using the flight computer • Practically apply your flight computer knowledge in flight planning to find your True Course, Winds, Groundspeed, Time, Distances and do basic calculations

4. E6B components

5. Circular Slide Rule Components • Inner scale (C scale) • Middle Scale (B Scale) • Outer scale (A Scale) • Rate mark • Something per hour • 10 mark • Altitude and Temperature Windows • Temperature Conversion

6. Computer Side • A and B Scale • Identical • Numbers get closer together as you go clockwise • Logarithmic, so that you can do multiplication and division using the two scales • Graduation also changes • Scale is infinite • “10” could be 1.0, 10, 100, 1,000…. • Pick out the reasonable choice when doing problems

7. Computer Side (Cont’d) • C Scale/Hours Scale • Used to find time • Speed index, big arrow at 60 • Total minutes on B scale, or read hours with minutes on C scale • Speed Index will always point to rates on A scale • Knots per hour, gallons per hour

8. Computer Side (cont’d) • 10 Index/Unit index • Box around the 10 on B scale and C Scale • Used for conventional multiplication and division • Ex. 9 X 8: set the unit index on the inner scale under 90 on the A scale. The answer reads above the 80 on the B side – 72! • Ex. 100/50: Place 100 on the A Scale across from 50 on the B scale and the answer reads on the A scale above the unit index of the B scale – 2!

9. Wind Side Components

10. Ground Speed and Heading You are planning XC to Devils Lake. You will be cruising at 6000 feet with 75% best power. What will be your ground speed and true heading? 1.) Find your Winds GFK 9900 1519+04 1629-01 • Set wind direction under True Index • Mark Wind Velocity up from grommet 2.) Find your True Course • Use Plotter and Sectional – 273 Degrees • Set in under True Index 3.) Find your True Airspeed • Use POH: 110kts • Move wind mark down to TRUE AIRSPEED 4.) Ground Speed reads under grommet, WCA reads under wind mark 5.) 260 degrees and 122 kts

11. Time • How much time will you need to make the flight? 1.) Set rate under ground speed (122kts) 2.) Find Distance on outer scale (70kts) 3.) Time (on inner scales) reads under distance (A scale).

12. Fuel Calculations • How much fuel will you need to make this flight in day VFR? 1.) Set rate to gallons per hour (from POH – 11.4) 2.) Add day VFR to time enroute 3.) Time reads on inner scale, gallons required reads above.

13. Time and distance to climb • You completely forget to calculate time and distance to climb on the ground with your POH. Your instructor wants you to do it now before takeoff. Use your E6B. 1.)How far do you have to climb? • Cruise Altitude: 6000 feet • Airport Elevation: 845 • 5155 2.) Use your E6B to divide the feet you need to climb by your rate of climb • 5155/500 fpm = 10.3 minutes for climb 3.) Put rate under groundspeed (122kts) 4.) Find 10.3 minutes on minute scale and read distance above. • 21 NM

14. U.S. to Imperial Gallons • Upon arriving in Devils Lake, you find that the city has been over taken by Canadians. You’ve only brought the minimum amount of fuel needed, and you need to fill up, but the Canadians only deal in Imperial Gallons. Your tanks are placarded at 100 U.S. Gallons. How many imperial gallons can they hold? • Set the imperial gallons arrow opposite U.S. gallons • Read imperial gallons opposite U.S. Gallons

15. Computing Winds 1.) On your way back to Grand Forks, your GPS fails (?!), due to your excellent pilotage skills and planning, you still know your groundspeed and True course, which are 120 kts and 090 respectively. You do, however, have an obsession with finding your winds. While your instructor flies, you pull out your E6B an decide to compute your winds….. • Set True Crouse under True index. • Set grommet over groundspeed • Make a mark over the wind correction angle across from the TAS • Set WC mark above grommet. • Wind velocity is the distance between grommet and mark, Wind direction reads under true index.

16. Ground and Track While computing your winds, you have completely lost track of your ground speed and track. So, you simply use the winds you have just computed…. • Set wind direction under True Index and velocity above grommet • Rotate your True heading, 090, under true index • Place wind dot on True Airspeed • Note wind drift in degrees • Rotate azimuth equal degrees • Adjust wind dot to True Airspeed • Read track under index • Read ground speed under grommet

17. Mach Number • You decide to make the flight more interesting and begin referring to yourself as “Captain Yeager” and giving your airspeed to ATC in Mach. What is your airspeed in Mach if you are cruising at 5500 and the temperature is -10 Celsius? • Rotate inner dial until you see Mach Index in the airspeed correction dial • Align Mach index with outside temperature (do not use IAS) • True airspeed reads on outer scale, Mach number reads on inner scale

18. Density Altitude and True Airspeed • If your Pressure altitude is 8,000 feet, and the temperature is -10, what is your density altitude? • Given a calibrated airspeed of 120, find your True Airspeed

19. True Altitude • 1. Set pressure altitude next to outside air temperature in the altitude correction window. • 2. Subtract station altitude from indicated/calibrated altitude to determine calibrated altitude AGL. • 3. Find calibrated altitude AGL on the middle scale and read the correction to station altitude on the outer scale. • 4. Add the correction to station altitude to get true altitude MSL.

20. True Altitude Computations