Beyond the major descent error there are several small errors that, while not terrible taken alone and promptly corrected, can become a real problem if they pile up and snowball. Single- pilot IFR, especially without an autopilot, is about the toughest job there is in aviation. Every effort must be made to minimize and spread our workload so it doesn’t get the best of us. Many of the errors discussed below have to do with managing workload.
It is very important to set all the radios up to the best advantage before launching into the soup. Once you’re airborne and calling Departure you won’t have time to fool around with radios. In order to do a thorough job of radio set-up you have to consider each radio individually and ask yourself if it is tuned in the most advantageous way, both sides (NAV & COM).
It doesn’t matter whether you do communications or navigation first, but I do all of one before proceeding to the other. I’m less likely to make an error if I stay focused on one category at a time. Most radio packages these days will deal with 4 frequencies at once. Use as many as you can so that when it becomes necessary to change frequencies you can do it with one or two button pushes; no tuning necessary.
Here’s an example for a departure from my home airport, Seymour, Indiana. I need to announce my departure on Unicom, so 122.8 goes in COM 1, Active. After takeoff I’ll need to contact Departure, which in Seymour is Indy Center, so 124.77 goes in COM 1, Standby. If we’re going to Shelbyville and Columbus (Indiana) to practice approaches I know I’ll need Indy Approach next so 124.95 goes in COM 2, Active. Next will be Columbus Tower so I put 118.6 in COM 2, Standby. Unicom at Shelbyville is also 122.8, which I already have available.
The same thought process can be applied to navigation frequencies, but with a different twist (pun intended). If we’re going to do the VOR approach into Shelbyville I can file direct Shelbyville VOR and put that frequency in #1 NAV, Active. The Columbus ILS frequency goes in NAV 1 Standby. Since I don’t need any other NAV frequencies I can put the same ones in the #2 NAV as a backup to #1. If I thought it through correctly I can do the whole flight without actually having to tune a radio. That is a huge workload saver. If it’s a long flight that will obviously require multiple frequency changes I do whatever tuning I can during the quiet cruising phase. I’m willing to gamble and put in frequencies I think will be correct. When the controller gives me the new frequency chances are I won’t have to do any tuning; the frequency will already be there. I immediately begin to have strong doubts about applicants who don’t tune radios, COM and NAV, before takeoff.
Besides not putting in all the reasonably possible frequencies there are two other radio errors to consider. The first is putting in the frequency but not adjusting the OBS. Frequency and OBS are kissing cousins; they don’t go anywhere without each other. Anytime you tune a NAV frequency you should set the OBS to the desired course. Even if it’s a localizer and the OBS setting doesn’t matter set in the final approach course anyway, for reference. You say you don’t know the exact course? Then put in the approximate one. Once you take off the adjustment to center the needle will be minimal. Every little bit of time saved helps.
The other error is failure to properly identify the VOR or localizer after tuning it. Some applicants become frustrated and confused if they can’t ID a station while sitting on the ground. That of course only works if the facility is on the field or very close by. If an applicant doesn’t understand line-of-sight and service volume I begin to have serious doubts about his readiness to be rated for IFR. In a related issue, you can’t ID a localizer if you are way off to one side. You have to remember to do it when the needles start to come alive and the flag drops. Flag and needle movement is the reminder.