The ILS approach hardware at Houston Hobby International pictured below is likely planted in the turf for the long term. Still, there’s a definite trend that points to an airspace based primarily on space-based navigation. As the avionics retrofit market booms along there has been lots of speculation about the future of ground-based navigation, including VOR and ILS systems. For owners looking to equip the aircraft for years to come, that’s muddying the buying decision. And that’s made more difficult with recent primary nav equipment based entirely on GPS, including Garmin’s new line of retrofit navigators. These navigators (the GPS 175, GNC 355 and GNX 375) don’t have VOR or ILS receivers, and shops tells me they are brisk sellers because they can shave thousands from the price of a retrofit, compared to going with Garmin’s VHF nav-equipped GTN navigators. Based on recent discussions I’ve had with buyers, sacrificing the ability to fly an ILS (or navigate with VORs) was either an easy decision or a tough one. Ultimately it comes down to where and how you fly. Dollar savings is the big picture, not only for aircraft owners freshening up old panels, but for the FAA maintaining an old infrastructure of ground-based navaids.
Flash back to somewhere around 2005 when the FAA decommissioned close to 300 NDB stations, and nearly 500 procedures. This resulted in an approximate $8 million per-year savings, rather than feeding the ancient equipment that was far past the service life. The ADF receivers in the fleet of aircraft weren’t getting any younger, or easier for shops to repair, either. If you’ve dealt with repairing a failed King KR85 or KR86, to name two popular boat anchors, you get it. Yanking the ADF receiver from the panel (and the sense antennas from the airframe) made room for GPS gear. Today there’s a similar trend brewing with other ground-based nav systems, including VORs, and the FAA has a focused plan to simply make them disappear.