Sparking a new option in ignition systems By Peter Lert
Our aircraft may be made of the latest
carbon composites; their instrument panels doubtlessly boast more
computation capability than the Manhattan Project.
Yet chances are, if they’re powered by
piston engines, their ignition systems are based on magnetos that Henry
Ford could overhaul blindfolded.
Meanwhile, the cheapest econo-box goes
motoring off to the supermarket with electronically-controlled ignition
that starts instantly, hot or cold, and continually adjusts its timing
to reflect engine loads and conditions.
Enter, at this point, Michael Kobylik and
Peter Burgher of Electroair, in Howell, Michigan. Both have EAA
pedigrees: Peter is a lifetime member, while Mike first came to Oshkosh
in 1974 and has hardly missed a year since, even while getting an
aeronautical engineering degree from Michigan State along the way.
Together, they developed an electronic
ignition system—with more than 1,000 systems installed on homebuilts
using engines as diverse as Subarus, Jabirus, and VW conversions, plus
Franklins and engines from the “big two.”
Now they anticipate a supplemental type
certificate for use on four-cylinder Lycomings in mid-August.
Advantages of electronic ignition include
a much hotter spark—actually a whole continuous “zap” lasting
through a full 20 degrees of crankshaft rotation—as well as variable
timing advance up to 39 degrees before top dead center based on manifold
pressure. This degree of advance goes about 10 to 14 degrees farther in
advance than the fixed setting of old-fashioned magnetos.
When replacing a magneto on a
four-cylinder engine, the Electroair system is triggered by a “mag
timing housing” installed on the original magneto drive pad.
Six-cylinder installations are slated to use a trigger wheel secured
behind the existing flywheel. The technology allows the system to “know”
the crankshaft angle every 6 degrees of engine rotation.
A typical installation replaces a single
magneto with the electronic ignition, while retaining the other original
magneto as a backup in case of failure of the electronic system or the
airplane electric system required to power it.
Electroair suggests that use of a single
electronic ignition system will improve engine performance while saving
fuel; this has apparently been borne out by the results obtained by
racers using both Electroair and other electronic ignition systems.
Pricing runs $3,400 to $3,500; the “show
special” drops it to $2,895.
After they earn approval for the
installation on four-cylinder Lycomings, the pair plans to next tackle
four-cylinder Continentals—such as the O-200—followed by
six-cylinder mills from both Continental and Lycoming.