L-1502
MO DAY YEAR
Champion Aerospace LLC
1230 Old Norris Road
Liberty, South Carolina, U.S.A. 29657
© 2009 Champion Aerospace LLC
www.championaerospace.com
CHAMPION AEROSPACE LLC PROPRIETARY INFORMATION - Subject to the restrictions on the Title page
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1-1
1.0 TECHNICAL REFERENCE
1.1
OVERVIEW
LASAR
®
is the integration of microelectronics with conventional magneto designs to provide
controllable ignition timing capable of optimizing engine performance while providing redundant me-
chanical backup ignition for safety. LASAR
®
senses engine RPM, manifold pressure, cylinder head
temperature (CHT) and other engine operating parameters, then selects the optimum ignition timing
from a three dimensional nonlinear Engine Personality Map (EPM) which is programmed into the
system’s microprocessor. The controller then signals the dual-mode magnetos when to initiate a spark
event, and controls the size and shape of the spark at the spark plug to optimally ignite the fuel in the
cylinder. At sea level takeoff power, ignition timing is set to the same fixed ignition timing as
conventional magnetos. At reduced power settings or higher altitudes, ignition timing continuously
varies between TDC and 50 degrees BTDC to optimize efficiency of the fuel combustion.
Automatic timing advance from the LASAR
®
system may cause cylinder head temperatures (CHTs) to
increase as fuel is burned more efficiently within the combustion chamber. Incremental CHT rise due
to ignition timing advance from a non-CHT controlled LASAR
®
system is typically 20°F. To
accommodate LASAR
®
system installations on airframes with marginal engine cooling or on airframes
where engine cooling characteristics have not been determined, LASAR
®
systems are offered with CHT
control circuitry that incrementally reduces the timing advance angle as CHTs approach a preset
maximum limit, thereby reducing CHT rise due to advanced ignition timing. If ignition timing advance is
reduced by the CHT control feature, engine performance improvements resulting from optimized
ignition timing will be reduced. In extreme situations where the engine continually operates at
maximum cylinder head temperatures, LASAR
®
will command the same ignition timing as provided by
conventional magnetos, resulting in comparable engine performance.
Two different limits (climb and cruise) are used to control CHT rise due to ignition timing advance.
These limits vary between installations and are preprogrammed into the LASAR
®
controller software.
During engine operation, the LASAR
®
system initially selects the climb limit whenever power is first
applied to the controller. The climb limit remains selected until a 15 minute timer expires. The 15
minute timer begins to count when CHT exceeds the cruise limit for the first time. Once the 15 minute
timer expires, the cruise CHT limit remains selected, including subsequent climbs.
Some airframe installations include an enunciator light mounted in the cockpit which becomes
illuminated when the LASAR
®
system is operating in the backup mode, or when the controller is
receiving power when the engine is not running. In automatic mode operation, a normally closed relay
within the controller is energized which isolates the enunciator light from ground and prevents
illumination of the light. In backup mode operation, the relay is not energized, allowing a ground path
for the light which then becomes illuminated.
With installation of LASAR
®
systems, existing engine speed signals from “P” leads and/or magneto
rotor sensors are not available. Electrical tachometers may be modified to correctly interpret the
LASAR
®
system’s four pole rotor magnets, or the speed signal provided the LASAR
®
controller.
1.2
SYSTEM CONFIGURATION
The controller is the heart of the LASAR
®
system. As a microprocessor based solid state device, the
controller will provide years of reliable service without the need of regularly scheduled maintenance
procedures. When the LASAR
®
controller has reached the engine TBO, it should be returned to
Champion Aerospace for re-calibration. No field service of the controller is authorized by Champion
Aerospace.
