Morgans wrote:
Planes (except from what someone wrote about the Theilert, which I have a hard
time understanding, and am unable to confirm) still have a mechanical connection
with the engine.
I think that's too strict a statement. Some do as a backup and some
don't. Most appear to use a throttle position sensor like cars do (and
boy do I hate the analog ones with a simple wiper arm over a resistive
field... you're just asking for uncommanded power excursions in a car,
much less in reported cases of failure on helicopters with that kind of
system).
Others exclusively use a mechanical connection, which of course means
it's NOT a FADEC system at all.
The Continental has every injector controlled by two computers. The spark is
controlled by a different computer for each cylinder, with each of the two plugs
in the cylinder having a different computer. There are dual sensors of each
type of sensor. There are two electrical systems for each set of computers.
Everything is protected from lightning strikes, and the associated surges.
All things considered, there is more protection and redundancy in the aircraft
FADEC than the aircraft without the FADEC.
That's a totally invalid conclusion. An engine without FADEC doesn't
require all those dual systems, because it can't fail in the same way.
For a traditional engine to fail in a way unique to its systems, both
magnetos must stop working. Does anyone here think that's a common
situation?
For FADEC to fail, all you have to lose is electrical power, or a pair
of sensors (ever have the crank position sensors or their wires fail on
your car engine? I have. In several cars. It's not at all uncommon.)
Worse, a software failure can screw up your FADEC. Google a bit, and
you'll easily find examples of oh, say, Airbus code failures that
stopped engines mid-flight. Or the example of the Chinook helicopters
where a FADEC code review found over 480 code anomalies in the first
15% of program lines.
Btw, did you see this Thielert AD because of engine stoppage due to
software?
http://www.casa.gov.au/airworth/airw...IELERT-003.pdf
You can be assured that before an engine is certified with a FADEC, that the FAA
has considered every possible failure mode, and has made sure that the engine
will keep running, if at all possible.
Now you sound a lot like what you claim is wrong with Mx. Prove that
statement if you can. I don't believe the FAA does any such thing. It
simply gives the manufacturer a set of guidelines. From what I've
read, there's no requirement beyond dual power systems to ensure that
the engine keeps running, only that a failure doesn't disentegrate the
engine or prop.
ANY aircraft engine can stop running. They are made to keep running, if at all
possible. An aircraft engine with a totally mechanical carb or injection with
magnetos has more possibility of stopping, than a FADEC engine, I would guess.
I do not have any facts to back up that statement.
Notice how I put it out front, when I was only guessing, or speculating? If a
certain other poster had stated his assumptions like that, there would not have
been all of the "personal" attacks.
Given that criterion, you should've put out front that you were
guessing on most of your posting. It's clear you're NOT an engineer,
despite the fact that you and newps seem to have Googled up some info
overnight. Does that mean we should all resort to personal attacks at
you?
Kev