HI, My Europa Classis has similar performance with a Jabiru 3300 and
Prince P-Tip prop,my cooling problems are still with me, but not so
severe, after Sylvester switched engines for me.As you are aware the
later model Jabs have larger cooling fins on the heads as well as other
mods.Sylvester used my A-026 to make his cowling and test for cooling,he
indicated to me that the cooling issue appears to be solved after
testing in the central Florida climate,it certainly took him quite a
while, here in Southern Alberta (Pincher Creek) I still get minor
problems on warmer days during climb out, but it is getting better with
more time on the engine, also we are at 3900ft elev which I am certain
impedes cooling.I have not had problems with the cooling air pleniums,I
also thought of trying an airmaster C.S.prop but am not sure if it has
enough twist at the hub to force the air through and as the Prince seems
to be almost doing the job I am going to leave it for a while to see
what happens when I have 250+hrs Hope this helps
Frank S Wood C-FIYD
----- Original Message -----
From: TELEDYNMCS@aol.com
To: europa-list@matronics.com
Sent: Monday, September 24, 2007 8:22 AM
Subject: Europa-List: Re: Jabiriopa performance numbers
In a message dated 9/24/2007 2:58:56 AM Eastern Daylight Time,
europa-list@matronics.com writes:
Would you care to share any precise speed measurements (3 GPS runs,
max
take off weight, record of altitude, OAT, etc.) ?
My Jabiru buddies are getting soooo discreet when it comes to actual
performance ;-(
Hi Gilles,
Sure, I've done many, many speed measurements, especially lately with
all the flow testing I've been doing on the wings and I'm happy to share
my numbers. Mine is a trigear with an empty weight of 909lbs. The C of
G is a little over 60". Typically what I see on a 75F day is 134 kts in
cruise at 2850 rpm at 3500' burning 4.6gph according to my Grand Rapids
fuel flow meter. One recent cross country flight I saw a TAS of 148kts
at 7500' at the same throttle setting. This is with a fixed pitch
Sensenich hollow carbon prop pitched as far as I can go and still
operate safely out of my 2200' strip, 700' msl, with two on board, full
fuel and baggage. I don't pay much attention to MAP, though, since there
isn't much I can to about it without being turbo normalized. I did close
off the overflow holes completely on the Jab air intake in an effort to
maximize MAP.
I have flown at 1450 lbs gross on several occasions and I'm still
climbing in the neighborhood of 1200-1300 fpm. If I back off to 2650
RPM, I cruise at 125kts and my fuel burn goes down to 3.8- 4.0 gph. I
have worked hard on getting the mixture well balanced between the
cylinders by playing with the needle jet and needle setting, as well as
the float level in the carby. I''ve also twisting the carby slightly
left from vertical to even out the mixture. I now have EGT's all within
about 40F of each other and my plugs are a nice tan color. I also am
running the Iridium plugs now with great success. This engine will idle
at about 500 rpm with the Iridium plugs and still maintain about 22psi
OP. I believe I have a handle on the cooling thing on all but the
hottest days, and then it's only an issue in extended climbs on the #4
cylinder. FWIW, these are the same days my Rotax buddies also have shown
cooling issues in a variety of different applications, including the
Europa. I did fit a larger oil cooler than what came with the engine.
That proved to work very well. I never see oil temps over 190F, even on
the hottest days. Fuel burn is very comparable to the 912s, too.
I don't know what it is that these other Jabiropa builder/fliers are
doing wrong, though. I would go so far as to say that the Jabiru is
superior in a lot of ways over the 912s, particularly in terms of how
smooth the engine runs and of course, price. Contrary to the blather
that has been spread about the Jabiru/Europa combo on a variety of
forums, I firmly believe the Jabiru is a fine alternative to the Rotax
912s, provided you follow Jabiru recommendations and undoubtedly it's a
hell of a lot cheaper than the 912s on this side of the pond. The parts
are also considerably cheaper, too. I'm really looking forward to the
day when Airmaster finally releases the new hub that fits the Sensenich
blades.
IMHO, I don't think the Jabiru factory cowl set fitted to the Europa
is going to work very well, though. I think it has to do with the "D"
shape of the intake holes. I think Andy Silvester/Suncoast has the
right combo on his cowl set with the round intake holes, but I think the
head cooling ducts he sent with the engine leave a little bit to be
desired. They're made from fiberglass and they tend to soften from
engine heat. That has proven to be a problem and one that has caused
some minor maintenance issues. I'm not sure the left duct is the right
shape, either. I'm playing with Sonex style sheet metal head ducts now,
but they are proving to be a real bitch to fit their odd shape to the 4"
round inlets. My "proof of concept" version is going to have a lot of
duct tape involved! I should have a left duct fitted later today unless
it's soarable again. ;-) More testing will follow and I suspect that I
will run much cooler even on hot days once I have them fitted. If it
works as well as I anticipate, I'll whip out a final version and
probably make a right side metal duct, too.
The Sonex boys seem to have all the cooling issues licked, so that's
the reason I'm trying what they do in terms of head cooling ducts to
achieve a better balance on the CHT's on really hot days and in extended
climbs. Below 90F I never see CHT's over 280F on either side, though,
and usually in the 240-250F range. Jabiru recommends 302F CHT max for
extended runs and 348F is max for short periods, like in climb. I will
see 320F on #4 on a hot day in climb, but it quickly cools to 285F or so
once I establish cruise. The rest stay below 300F.
And before anybody chimes in and tells me I don't know what I'm
talking about when it comes to the Rotax and so everybody will know I'm
not pulling my Rotax numbers out of the air, I also own an Aeromot AMT
200S Super Ximango motorglider with a certified 912s installed swinging
a Hoffman 3 position prop. So, I do side by side comparisons regularly
and I'm very familiar with the numbers on both engines. I have about 135
hours now in the Ximango and 117 or so in the Europa, so plenty of time
to compare numbers. FWIW, I like the 912s, but it is very complicated
compared to the Jabiru and it shakes like hell when you first crank it
up. The Jab is much easier to crank when cold. It just roars to life
after a few swings of the blades without all the shaking and no choke is
ever needed, even on cold days. I think the Jabiru is quieter, too. We
tested it with dB meter and my neighbor's lawn mower is louder than the
Jab at take off power at similar distances.
Graham, in regard to your question, I already sent some Jabiropa guys
over your way a fairly extensive overview of what I've done. Is there
something specific that they need to know? I'm happy to share and I've
got tons and tons of pictures.
Regards,
John Lawton
Whitwell, TN (TN89)
N245E - Flying
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