Big Things Coming
By Nadav Eiron, ANN correspondent
Teledyne Continental has had FADEC in the works for a while, but
lately more and more actual hardware starts showing up. On display
at Oshkosh this year were two new FADEC conversions for existing
airplanes on display in the TCM tent: a Cirrus SR-22 installation
developed in-house by TCM, and a Piper Malibu installation by
Malibu Power and Propeller.
While the Malibu STC is still quite far out, contingent on the
certification of a new variant of the TSIO-550 engine by
Continental, sources close to TCM tell us the SR-22 project is in
the very final stages before certification.
The FADEC system in the SR-22 controls fuel flow into the
engine, and spark timing. Propeller RPM is still controlled
separately, by a conventional hydraulic governor. However, the
mixture knob is gone from the cockpit.
The system uses a pulse modulated electronic fuel injection
system and an electronic ignition system. System inputs include
temperature measurements (EGT and CHT) from each individual
cylinder, RPM, throttle position, and crankshaft position.
Under the cowl are three boxes, each housing two separate FADEC
computers that control two cylinders. During normal operations,
each of the two computers inside the box controls a cylinder, while
monitoring the data for the other cylinder controlled by the box.
(File Photo of Engine)
If one of the computers fails, the other computer can take over
control of the second cylinder as well. Since engine functions now
depend entirely on an electrical power source, FADEC installations
require two completely redundant sources of power.
The Cirrus's dual bus design makes this relatively easy. The
FADEC system is fed by both the main bus and the essential bus. The
STC will also include a second 70 amp alternator that will be able
to support all the aircraft's systems, including FADEC, if the
primary alternator fails.
Other than simplifying engine management, the FADEC system also
enables performance improvements. While fuel savings are expected,
our sources tell us that the more noticeable improvement is in
available power. We were told that the FADEC equipped SR-22 test
plane "consistently beats Cirrus's POH numbers". Performance is
improved most notably in climb.
Reliability and maintainability is also expected to be improved
with FADEC. The system records all airplane parameters for future
analysis. Several levels of analysis are planned: mechanics can
download data to a laptop or PDA in what is referred to as 'Level 2
Analysis' that is meant to aid in basic troubleshooting and
maintenance of the engine.
'Level 3 Analysis' is through an upload of the engine
information to TCM's website for long-term trend analysis. 'Level 4
Analysis' combines level 3 data with additional data such as oil
analysis and compression tests that are entered manually.
At the opposite end of its product range, TCM also introduced
the LSA (as in Light Sport Aircraft) version of the venerable O-200
engine. The LSA version, while still producing the same 100HP that
the regular O-200 puts out, is designed to be lighter-weight and
lower-cost.
Weight reduction comes from somewhat lighter structure, and use
of some "automotive-like" parts, such as spark plugs. TCM is
planning to offer the LSA O-200 through OEMs only, either in
completed airplanes or as parts of LSA kits. Development and
certification of this engine is "moving rapidly" according to our
sources.