The Lost Art of Heading
This article originally appeared in IFR magazine, Mar. 2006.There is a chain of FBOs in the Midwest famous for warm cookies, parrots with rude vocabulary and impressive line ladies. The ramp full of airplanes indicates that pilots are attracted to, and distracted from, competing FBOs by these interesting things. Looking in the cockpit of our airplanes, it's clear that pilots are also attracted to the interesting avionics that bring a huge bandwidth of information into the cockpit. Whether the magic in the cockpit is a pair of 12-inch, color, flight displays, or handheld GPS with downlink weather and satellite radio, these tools improve our situational awareness and that's good. The problem is that a picture of the airport with the final-approach course line on the moving map can distract a pilot's attention just like the short shorts on the line girls at the Kansas FBO. Both are fun to look at, but when it really matters, what we should be watching is the CDI, the HSI, or the pretty girl's hands, to guide us safely to our destination. Bad habits creep into all areas of our flying and the solution is usually getting back to the basics. Our primary navigation instrument should be the HSI or the CDI (for simplicity's sake, we'll call either one a CDI). There are times when the ADF or RMI might be the primary instrument, but both are scarce in GA airplanes in the U.S. A moving map should be used for situational awareness. Using the moving map instead of the CDI will work, but -- especially if a glideslope is involved -- the results will be poorer than if the focus was on the CDI. The reason is simple: There are fewer instruments in our scan. Partial-panel IFR is a scary thing to talk about, but once the initial shock passes it's not that difficult. With fewer gauges to scan, we get back to them more often and the result is lower workload. Adding the moving map to our scan adds to the total workload and degrades pilot performance rather than helping it. Scanning the moving map to maintain situational awareness in a procedure turn or holding pattern is great, but once the final intercept angle is established, the CDI should become the primary navigation instrument. After joining the final approach course, an occasional glance at the moving map or the GPS ground track is useful to determine the distance from any step-down fixes or to confirm our reference heading.