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Old July 22nd 04, 03:06 PM
Ryan Ferguson
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Thomas Borchert wrote:
Ryan,


hey can be summed up in three words: TCM, network, and MCU.



Could you explain a little more, please?


TCM: I think Continental's quality of materials and construction is poor
these days (see Deakin's comments on TCM at AVWeb) and I would have
vastly preferred a Lycoming powerplant in the Cirrus. The current
engine is a operating expense and safety liability in an otherwise
well-thought out airplane. The TBO talk of 1,700 vs. 2,000 is largely
moot because the engine is not likely to make it past 800-1000 hours
without being topped no matter how it's operated.

Network: Components by Emax, Avidyne, Garmin, S-TEC, and L-3 all
communicate together via ethernet. A piece of garbage occasionally
appears in the data stream and causes problems - for example, the
altitude preselect may stop functioning mid-flight, or the autopilot may
stop receiving course or heading signals from the PFD. These problems
are transitory and impossible to troubleshoot. The solution is to
integrate, which is what Garmin is promising with the G-1000. Garmin is
also building their own autopilot, which will obviously be designed to
seamlessly integrate with the G-1000. A/P integration was one of the
key goals of the Garmin design team, according the G-1000 product
manager when I spoke with him after a presentation on the G-1000.

MCU: The Master Control Unit provides electrical services such as
voltage regulation and overvoltage protection, etc. It's mounted on the
left side of the firewall in the engine compartment. Oddly, it is a
single point of failure across both alternators. A failure of the MCU
makes the all-electric SR-22 a battery-powered airplane in a heartbeat.
This is supposed to be a rare event, but we've replaced two MCUs in
one of our SR-22s already.

Another common misunderstanding is that the airplane "can't" recover
from spins with CAPS. According to Cirrus' test pilots, the airplane
recovers from spins via conventional recovery techniques. The latest
iteration of the SR-22 and SR-20 POH indicates the proper recovery
method is to first try the conventional PARE technique, and if not
effective, to activate CAPS. Spin certification compliance via CAPS was
simply a matter of saving money to certify the airplane. I don't
suggest that the airplane can or should be spun, but from what I've
heard directly from the horse's mouth, spin avoidance and recovery are
no more an issue in the Cirrus than any other single-engine airplane.

-Ryan