Alth
Innovative suppliers have responded to the frustration of premature vacuum pump failure with new designs and backup strategies to include electric attitude gyros. Now, alternators are getting some attention. At Oshkosh in recent years, weve noticed a profusion of new alternator designs that are lighter, smarter and more efficient than the automotive adaptations found on the typical Lycoming or Continental engine. Unfortunately, while improved starters have found their way into the certified market-see
Aviation Consumer August 2006 for a report-new tech alternators have been largely limited to the Experimental segment.
This year, thats beginning to change. At least four companies are migrating what used to be Experimental-only products into the certified arena and more may be on the way. As with lightweight starters, these new alternators are lighter and use improved materials and designs in the hopes of offering better efficiency and reliability. Moreover, these new alternators develop cleaner, less electrically noisy power, which is a must for aircraft that are increasingly equipped with all-electronic instrumentation. Heres a survey of whats on the market.
Design Push
For an alternator, the equivalent of a 100-meter sprint is a night IFR departure, just before takeoff as the airplane idles with all its lights and avionics running at full tilt. Alternators don’t like the combination of low RPM and high electrical draw, which is why in many aircraft, the low-volts light blinks on at night. With a weak battery, this can be a recipe for a disastrous electrical failure in a single-engine airplane if the alternator fails inflight.