Hi Frans,
I'm a bit puzzle by your first picture: are the blue pipes directly
connected to that flat radiator? I think these end at the bottom level of
the exhaust, so what is the shape of the radiator...
Other question: have you experienced (or do you think there is) differences
on that topic between 914 and 912?
Max Cointe
F-PMLH TriGear Kit #560
912ULS Airmaster 420 hours
mcointe@free.fr
-----Message d'origine-----
De: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] De la part de Frans Veldman
Envoy: lundi 25 juin 2012 23:10 : europa-list@matronics.com Objet: Re:
Europa-List: Re: Contact detail & Help
Hi Karl,
> I have been following your developments with great interest and I
> think that the end result is just plain amazing.
Thanks!
> Now, top speed is very useful for testing drag improvements, but you
> don't cruise at those speeds, do you ? When you are touring, what are
> your preferred settings regarding speed, MP, rpm etc., and exactly
> what is your fuel consumption then.
I found the sweet spot of the aircraft is with 27 inch MAP, where it usually
cruises with a speed somewhere between 120 and 130 KIAS, depending on C of G
and some other obscure factors. Fuel consumption used to be 16 to 17 liters
per hour, but I have observed this year that the fuel consumption has
increased to 18 liters per hour. Maybe the carbs need an overhaul or so.
RPM is usually between 4800 and 5000 RPM, this feels best for the engine. I
have a two blade prop and at lower RPM's it feels less smooth.
Of course actual settings depend on various circumstances. With a strong
head wind we usually advance the throttle a bit, with a tail wind we enjoy
the lower fuel consumption of a lower power setting. We fly 90% of our
cruising with power between 26 and 28 inch.
With higher power settings the fuel consumption goes up faster than the gain
in speed. Other than in a car, a higher speed doesn't give any other feeling
than a lower speed, it just gives the same sensation. One hour flying is
still one hour flying. On a 3-hour trip I rather enjoy an additional 10
minutes flying and have a free meal than just cranking up the fuel
consumption, paying more for less fun. AVGAS can be close to 3 Euro's per
liter over here, so saving 10 liters on a trip can save enough money to have
a dinner for two! ;-) I love telling friends that flying there isn't more
expensive than getting there by car.
> If the rest of us mortals wanted to implement some of your changes
> without too much expense, what would you recommend ?
There isn't much money involved actually. The radiator costs about 300
Euro's, the heat exchanger a bit less. You can do without the heat
exchanger, I have been flying one summer with the stock oil radiator fed by
a 2" Scat tube via a wedge diffuser. Apart from the long warm up time it was
quite an improvement over the tandem setup. Best thing to do is to scrap the
stock coolant radiator, dog house, duct and associated hardware and just
install a thin radiator in a 45 degree angle in front of the exhaust and
turbo.
The main hurdle here is to shape a new underside of the cowling. You have to
be brave enough to cut the dog house away, and then insert a block of blue
foam and start cutting, rasping, sanding until you have the shape you
desire. Anyone who wants to make a mold out of my cowling is welcome to do
so, provided I'm allowed to use that mold to make a new light weight carbon
cowling for myself. ;-)
BTW I'm not the only one who devised something like this. See the attached
picture. This is another configuration with a thin radiator in a 45 degree
angle, although it lacks a cowl flap and heat exchanger for the oil. (Oil is
cooled by a radiator, fed by a NASA duct on the port side, you can see it on
the picture). Also this owner claims very good results with his setup on his
914 engine. The key really is to use a thin radiator and mount it at the
belly so the "used" air can take the heat of the exhaust with it, and enjoy
the benefits of a very sleek cowling, excellent cooling, low pressure
losses, and minimal cooling drag.
Anyway, my cooling design is not an exclusive invention of me but the
combination of ideas and experiments of multiple Europa owners who believed
that the cooling of the Europa could be improved other than by using draggy
brute force solutions.
> What is the part number for the
> heat exchanger and exactly where did you install it ?
See picture, taken from under the engine. The heat exchanger is mounted
behind the engine. This was the first setup, with the stock coolant
radiator, hence the configuration of the coolant hoses pointing downwards.
In the current design the hose routing has been changed to accomodate for
the thin belly radiator.
If you really want to go this way, contact me privately for more info.
One caveat though: this heat exchanger has very thin canals and is not
compatible with Evans coolant due to its viscosity. I use it with 50/50
without problems.
> It also had a very
> small (8AH?) battery.
I also have a small 8Ah battery, never needed anything more than that.
But I have a second alternator (mounted on the vaccuum pad) so I don't need
the battery as a backup during flight, I just need it for starting.
Frans
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