Hi Bob,
I have manifold pressure reading for my Arplast / Smart Avionics CS prop
combination, but I actually prefer to use the Benwick fuel computer set to
"fuel flow", which is very accurate and gives a precise indication of power
without having to adjust for atmospheric pressure and altitude. Perhaps
Francis could be persuaded to accept one or the other methods of monitoring
power.
Regards,
William
----- Original Message -----
From: "R.C.Harrison" <ptag.dev@tiscali.co.uk>
Subject: RE: Europa-List: Manifold pressure gauge
>
> Hi! Richard
> I find myself a little bemused why the resistance to fitting a Manifold
> Pressure Gauge, apart from needing room on the panel? If you have a CS
> installation without the gauge you will have no indication as to how you
> are loading the engine, that is to say RPM is no longer an indication of
> power.
> So it becomes possible to run the engine at all RPM in a labouring
> condition not to be recommended for cruise configuration with respect to
> fuel consumption and engine well being. My MT CS prop. will hold the
> engine RPM at say 2,500 even with maximum MP at say 30 inches, where
> maximum recommended is about 22 inches. The rule of thumb is so called
> "squared"
> Which means 24" FOR 2,400 rpm ON A DIRECT DRIVE ENGINE. However I've
> managed to identify on the Jabiru 3300 that a lower MP with a slightly
> higher RPM gives a better fuel performance. (no snipes about fuel usage
> comparison with the Rotax thanks Duncan the scenario still applies)
> Problem without a MP Gauge is knowing the effect of the ambient and
> altitude changes and in pressure relative to engine performance.
>
> Regards
> Bob Harrison G-PTAG Europa Kit 337 MKI/Jabiru 3300
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of Richard
> Holder
> To: europa-list@matronics.com
> Subject: Europa-List: Manifold pressure gauge
>
>
> Hi, just received the Dec 2004 issue of the Europa Flyer.
>
> I am very interested to see that Brian Allsop managed to get his Kremen
> CS/VP prop approved without a manifold pressure gauge.
>
> When I put my Airmaster on my aircraft at the initial build I saw that
> Airmaster and Rotax did not require a MAP and so built my panel
> accordingly.
>
> When it came to the Permit to Test Fly Donaldson INSISTED on the fitting
> of
> a MAP. I argued that there was no requirement from the manufacturer of
> either bit of kit. He insisted. Sending me a copy of some JAR "minimum
> equipment" list which showed that a MAP was required for a CS prop.
> Probably
> written in 1948 !
>
> Anyway he is the king of this stuff and I had no option but to fit it
> (spitting !) on a sub-panel that destroyed the looks of my panel.
>
> Actually it is very useful for setting power.
>
> So how come Brian didn't need one ? It is only required for CS props -
> not
> VP props.
>
> I am interested about the description of VP and CS in the article. The
> Airmaster gives a VP option just as an aside. I have not used it yet.
> The
> Airmaster controller has switched positions for Take-Off (5700 rpm)
> Climb
> (5400) and Cruise (5000) plus a position where you can set any rpm you
> want.
>
> The Kremen seems to be a mixture of CS and VP almost as separate
> functions,
> when really the CS could be used all the time if all the required
> features
> are there.
>
> Unless someone disagrees !
>
> :-)
>
> Richard
>
>
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