Up Up and Away

[John Dammeyer]

Hi Phil,

>
>Date: Mon, 11 Oct 1999 00:50:01 +1000
>From: Phil Lamovie <phil at injec.com>
>Subject: Re:Up Up and Away
>
>Hi John et al,
> sorry 'bout the html had to reload NT (i moved the mouse)and got all
>of the default settings.

I've pressed a few wrong buttons too.  ;-)

>Please note the total lack of Patents for Altitude correction of
>aircraft fuel injection computers. Also total lack of altitude sensors
>on all Ford and GM vehicles. I suppose they don't have mountains in
>the
>USA.


That GM and Ford don't use them is irrelevant.  They also didn't use overhead
CAM engines until the Japanese and European automakers started impacting their
bottom line.  Once fuel prices changed in the US their attitude did too.   Most
California polution testing is done close to sea level and they have the most
stringent specifications.  The tests are done at idle while the O2 sensor is in
closed loop mode. A rich mixture at Full Torque RPM is never tested for and most
vehicles don't run in that mode anyway.  An engine idling at a high RPM because
it was tuned at sea level but tested at 5000' ASL would be sent to the shop
where the engine would be adjusted to pass the tests at that altitude.

An inability to patent basic physics is not an indication of the lack of basic
physics.

>
>My company has also supplied ECUs for Aircraft that have flown from
>England to Australia, film is available from National Geographic.
>I promise they were all fitted with absolute sensors. The engine were
>all dynoed on a thirty foot tower (they had very big props about 33
>feet
>span) 650 hp at sea level)) and then flew half way around the world.


The reduction gear would have to keep the propellor tip speed below the speed of
sound and in either case the aircraft propellor is primarily interested in best
fuel economy at maximum torque - not maxium horsepower.

As I said before,  it's not that the MAP-RPM doesn't or won't work;  it's just
not the optimum solution and the pilot that might have to land his aircraft 100
metres from the runway with empty tanks would prefer the optimum solution.

>
>Hope the simplicity of it is not too hard to fathom.

>Phil


I think I'll leave this discussion rather than retort on simplicity verses
complexity and perhaps we can just agree to disagree.

Regards,

John