"Morgans" wrote in message
...

"Walt" wrote in message
oups.com...
I didn't really want to get involved in this thread since, IMHO, it's a
clash of personalities more than knowledge of FADEC, but I'll offer
something that's vaguely on topic.

I own a new Subaru Outback. It has an electronic throttle, i.e., there
is no physical connection between the gas pedal and the engine.

Good post.

A couple differences between autos and airplanes, with "FADEC".

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.

The autos do not have any redundancy built in. Airplanes do.


Auto's have redundancy in the form of parallel software calculations and
seperate montior chips in the PCM. But, since the primary concern is "torque
greater than demand" what the redundant software / chips typically do is
shut things down when a discrepancy is detected. You will also find that the
pedal input to the electronic throttle control will have multiple position
sensors that provide signals that have different chararacteristics (eg. one
increases as the throttle is depressed, while one decreases). Air flow from
an air meter provides a redunant input to the throttle position. But, again,
the action taken is generally to reduce power or shut down the engine to
avoid the #1 worry bead.

--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.