Accident Analysis: State of the Art

Many students may wonder why the navigation section of the airman certification standards still requires competence in using “ground-based navigation systems,” which for most practical purposes means VORs. Grizzled veterans may pretend to mourn the disappearance of nondirectional beacons (NDBs), but in fact the VOR represented a huge advance in reducing pilot workload, eliminating the frantic and error-prone mental arithmetic needed to figure bearings to or from the station. Installation of a national network of VORs was the foundation that made the current IFR structure possible.

Still, with global positioning systems that pinpoint your location within a few feet now available in everything from sports watches to telephones, why are we still wasting time tracking radio signals?

Leaving aside the fact that it is on the test, meaning you’ll have to learn it regardless, there are powerful reasons VOR navigation is an essential component of your tool kit (see “Viva La VOR,” p. 36). Start with the fact that since GPS originated as a military system, it’s reasonable to assume foreign adversaries have at least researched methods of disrupting it. That might never happen, and you may not be in the air if it does, but aviation is all about having options. Radio transmitters operate on line of sight, making it extremely difficult to jam them nationwide. The FAA’s decision to preserve a “minimal” network of VORs sufficient to support instrument navigation is motivated precisely by the need for a backup in case of widespread GPS outage.

More mundane reasons are more plausible. Portable devices are prone to battery exhaustion, not to mention being accidentally left at home. Some screens are difficult to read in sunlight, and a certain very popular tablet computer is prone to shutting itself off to avoid overheating. But almost any airplane with an electrical system is likely to have at least one panel-mounted nav/com that (usually) goes on working as long as the electrons flow. Knowing how to track to an on-field VOR station, or pinpoint your location by plotting intersecting radials from different transmitters, still can be the difference between gassing up at an unfamiliar airport and a precautionary landing on a farm road before the engine quits.

Yeah, it’s old technology. So’s the internal combustion engine. They still work, so we still use them.

AOPA Air Safety Institute statistician David Jack Kenny’s respect for vintage technologies extends to ownership of no fewer than four manual typewriters.