The CR Computer has been a favorite of professional pilots, navigators, and flight engineers for approximately 20 years. If you began your flying career with the basic E6-B type computer you will find both similarities and important differences between the E6-B and the CR Circular Flight Computers.
Once you become familiar with the CR computer it will more than likely be your favorite cockpit aid. Many of the scales on the calculator side are similar to those found on the E6-B. However, the CR has several new functions available on no other computer, making it the most useful instrument for modern piloting needs. The wind side of the CR uses a wind triangle that is somewhat different than the E6-B and it provides quick, simplified solutions to all course navigation problems.
APR offers three models of the CR flight computer. The larger CR-6 provides maximum readability while the smaller CR-3 and CR-4 models provide convenience. Only APR’s computers have the exclusive APR Microset that allows the computers to be aligned for total accuracy before leaving the factory. Although they are precision instruments you will take pride in owning, the information they give you is only as good as the information you give them. For this reason, we recommend you take the time to study this manual carefully.
The calculator side of the CR computer is designed for quick, accurate computation with problem solving capabilities adapted to current aviation needs.
The wind-computing side of the APR CR computer applies the latest "state-of-the-art" technology. With this new instrument your pre-flight and in-flight calculations are easier and more accurate.