You wrote an eye-watering check to the avionics shop for the latest and greatest gear, but that doesn’t mean the new suite is invincible. An electrical failure in a single-alternator, single-battery aircraft will make the unprepared wish the vacuum system wasn’t in the rubbish bin on the shop floor. Herewith is our plan for affordable belt-and-suspender backup.
• Auxiliary com antenna. Modern VHF comm transceivers make plenty of power and have good reliability, but an audio system or electrical failure could have you talking with a portable radio. You won’t talk far—maybe a few miles—without an external comm antenna. While the airplane is opened for the installation, ask the shop to install a belly-mounted antenna with a run of cable into the cabin. Either install a BNC antenna connector on the panel or simply coil the cable up in a map pocket so you can plug in a portable.