Uploaded August 2025 | Updated September 2026, 2 weeks ago

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While the E6B “Whiz Wheel” is the most popular mechanical flight computer still in common use, there are many alternative designs, including the Jeppesen CR-3. Patented in 1955 and manufactured by Jeppesen-Sanderson, a company with a long and storied history in aviation navigation, the CR-3 dispenses with the slider used by Dalton-style computers, instead using a more compact disc mechanism to perform wind triangle calculations.

E6B video: youtu.be/__0F6JAXj8U
Pelorus / Course Corrector video: youtu.be/Lsa_UrnO-e4
Drift Sights video: youtu.be/weT_cEWoCBQ

0:00 Introduction
0:50 Elrey Jeppesen
2:21 Jeppesen & Co. And “Jepp Charts”
3:36 Other Flight Computers
4:15 CR-3 Patents
4:38 Time-Speed-Distance
6:00 Fuel Consumption
6:08 Unit Conversions
7:13 Altitude
9:11 Airspeed
11:26 Mach Number
12:45 Wind Side
13:33 Magnetic/True Course Conversion
14:02 Crab Angle
16:36 Wind Calculation
18:07 True Course / Ground Speed
19:50 True Heading / Airspeed
21:05 Off-Course Correction
22:03 Outro


SOURCES

news.google.com/newspapers?id=YMheAAAAIBAJ&sjid=TTIMAAAAIBAJ&pg=2353,4035993

web.archive.org/web/20100719164330/http://magazine.continental.com/200907-continental-facts

sliderulemuseum.com/Aerospace.shtml

web.archive.org/web/20120627082136/http://airportjournals.com/Display.cfm?varID=0702007

web.archive.org/web/20150330005224/http://dmairfield.com/people/jeppesen_eb/index.html

web.archive.org/web/20061130085748/http://www.newyorker.com/talk/content/articles/061030ta_talk_mayer

patents.google.com/patent/US2767919A/en

https://physicsmuseum.uq.edu.au/sites/default/files/CR-3-Instructions.pdf

flight-computer.de/Air-Navigation-Computers.pdf