> Paul,
>
> snips..
>
> By the way, it is a real thrill, while also a bit scary to be flying
> around
> above the clouds in an "experimental" airplane that you put together in
> your
> garage and which uses a car engine along with a whole bunch of
> do-it-yourself parts. You can't help but wonder if you did everything
> correctly as one snafu could easily ruin your whole day. With that said,
> I'm
> beginning to feel a bit more comfortable about the whole experience now.
> But
> give me a couple-hundred hours of trouble-free flying and then ask me
how
> I'm feeling.
>
> Mark
> 15 hrs (and counting)
>
> My mother told me never to fly anywhere unless I could
> see the ground :)
>
> Things happen. Plan on it. I am not supposed to be
> saying that on here but never the less always have a plan B.
>
> Judging by what I have seen so far of your excellent
> installation I think you have less to worry about than most.
>
> BTW what are you seeing on the "cylinder head" temperature
> gages so far? You are our only experimenter on those.
>
> How is the muffler working out?
> --
> Paul Lamar ...No rotor no motor.
>
> Paul,
> Thanks for the vote of confidence.I try to fly high so that I
> have more options, just in case.
>
> I haven't looked at the CHT's in a while as you must page through a
number
> of screens on the EM-2 to get to the EGT/CHT page.Not much you can do
> about
> it anyway.I like to keep the main page up during the initial climb, but
> the
> most important info is on the top and bottom lines which don't change
when
> paging. The EGT's typically run around 1600-1650 in cruise. I'll check
the
> CHT's on my next flight and let you know what they're reading.
>
> The " R.B.Wagner" exhaust tubes seem to be holding up just fine also. So
> is
> my homemade auger muffler, although guys tell me that they can hear me
> coming from 5 miles away. I tested a Hush Power II resonator muffler and
> it
> is amazing how much quieter it is over the auger muffler. For the first
> time
> I could actually hear the prop above the exhaust. The body of the
muffler
> is
> only 12", overall length is 17.5" but a couple of inches can be cut off
> both
> ends to shorten it. It is compact enough to fit under the cowl. I
couldn't
> bring myself to hang a muffler under that beautiful airframe. This
> provides
> a good alternative. Dennis H. has one of these on his RV-7A and it is
the
> quietest airplane on the field. Now that's something you don't hear
often
> when discussing rotaries.
>
> By the way, a side benefit to the oil/water exchanger is that the oil
> keeps
> the water hot enough so I don't need a thermostat or cowl flap.
Yesterday,
> I
> flew and the oat was 44* F.The coolant was up around 170-175 in climb
and
> settled down to 150-160 in economy cruise.Oil temps track 10-15*
higher.If
> it gets much colder, things may change and I may have to add a cowl
> flap.The
> 20B burns about 12.3 gph in economy cruise.Not too shabby, especially
> since
> I can burn auto fuel which is more than $1/gallon cheaper.
>
> Mark S. 16 hrs
>
> There is no cheap replacement for thick RB Wagner SS exhaust
> pipes :)
>
> You certainly have plenty of cooling capacity in the winter
> time :)
>
> 12.3 gph is 73.8 pounds per hour so at a well leaned BSFC of
> .47 (150 F lean of peak.) that would be about 160 HP. At .5
> BSFC it would be about 150 HP. At that HP rate the 3 rotor
> TBO should be 5000 hours :)
>
> How fast are you going at 12.3 gph and what is the EGT?
> --
> Paul Lamar ...No rotor no motor.
> Paul, That was cruising in overdrive.;-) Best I recall, it was about
> 105-110 kts indicated, 123 kts TAS (142 MPH) and about 17" MAP, highest
> EGT
> was 1600 +/- .I'll verify that again on next flight. I'm still working
on
> getting the EM-2 fuel totalizer calibrated. I know I'm close, but not
> quite
> there yet. Best cruise speed I've seen so far is 173 kts TAS (200 MPH).
> This
> was at 1700 prop rpm, 5200 engine rpm, wot and no wheel pants.I can't
wait
> to see what it will do with the wheel pants installed and higher
> prop/engine
> rpm. That M/T c/s prop sure makes things nice. I usually set the prop to
> 2250 for takeoff. That gives me almost 7,000 rpm for takeoff. She's
> usually
> airborne before I hit the first turnoff. Once I'm up to about 110 kts I
> start dialing the prop speed down to reduce the stress on the engine and
> psru, and also to lower the fuel burn. I usually see about 26-27gph (
> 160#/.6 BSFC = 265 HP.... 160#/.65 BSFC = 246 HP) on the EC-2 during
> initial
> climb. It usually climbs in excess of 1500 fpm at 105-110 kts. Not too
bad
> for a 4-place airplane. I haven't done a full-power climb at Vx yet.
>
> Mark
>
> Thanks for the performance data. I'll have to do some data reduction. I
> assume you have the 2.85:1 PSRU since you can reach 7000 RPM or can you
do
> that with a 2.17 :1 PSRU?
>
> My C182 cruises at about 150 MPH on about the same 12 gph fuel burn.
> Of course it won't cruise at 200 MPH :)
> --
> Paul Lamar ...No rotor no motor.
>
>
> Paul, I flew again today, my first official cross-country in a
> rotary-powered airplane.I flew from Lockhart (50R) to Taylor (T74),
> staying
> outside of the ABIA class C airspace.It took an hour from engine start
to
> "clear of the active" and I burned approx. 11 gallons according to the
> capacitive fuel gages (on the ground). I managed to snap a couple of
shots
> of the EM-2 and EFIS for your viewing pleasure.The TAS readings differ a
> bit
> between the EFIS and the EM-2. The oil & coolant temps to pay attention
to
> are the ones on the EFIS.The EM-2 oil temp is the temp after the oil/air
> cooler, but before the oil/water exchanger.The EM-2 coolant temp is the
> return coolant temp, after the radiator (returning to engine).You can
see
> that the coolant and oil temps (shown on the EFIS) are within about 10*
of
> each other.
>
> The highest EGT is shown on line two and is rotor #1 (nearest the
> flywheel)
> and is at 1647*.The two bars to the right of the #1 show a graphical
> representation of the EGTs (#2 is not working as is evidenced by a gap
> between the #1 and $3 bars).I checked the CHT readings and the highest
was
> also #1 (nearest the flywheel) as I would have expected.It was reading
> 195-200*.The fuel readings (lower right of the EFIS) were Left - 33
> gallons,
> Right 29 gallons when in the hangar before the flight.You can see that
the
> left is reading 25.5, which is pretty close, but the right has gained 7
> gallons and is reading 36.1 gal.Maybe I should apply for a patent.:-)All
> kidding aside, I really need to get this corrected. I'll be trying out
> your
> suggestions soon.Mark 17 hrs
>
> Congratulations on the first cross country. Is that CHT 200 C or 200 F
> Mark.
> --
> Paul Lamar ...No rotor no motor.
>
>
> Paul,
>
> That would be 195-200* F.
>
> Mark
>
> Amazing! At that rate we are a hardly using these engines. A piston
engine
> CHT runs up to 400 F. I sure hope those thermocouples are working right.
> If
> so I suspect 400 HP would not be out of line for a p-port 3 rotor
aircraft
> engine. Maybe 500 HP with a 3:1 PSRU. At that level we would be pushing
> turbine engines in power to weight ratio with 75% of the fuel burn. I
> wonder
> when this is going to dawn on a major aircraft company. Just think what
> Wankels could do with a turbo compound.
>
> CHT is the one parameter that measures the capability of the engine to
> generate HP long term. We are just seeing the tip of the iceberg on the
> potential of Wankel aircraft engines.
>
> Paul Lamar ...No rotor no motor.
>
> Van is always harping on people about adding HP to his designs. He
> assumes
> they are going to install a larger displacement and consequently
heavier
> aircraft engine. In a rotary that is not necessarily true. HP can vary
> over a wide range depending on how it is tuned. A p-port or turbo can
> drastically increase the HP with little or no weight penalty.
>
> The six pinion Ford planetary set is completely up to the job assuming
it
> is kept cool enough. It is used in the Ford A4OD auto transmission and
> deals with 650 foot pounds of engine torque output by the Power Stroke
> diesel. The max torque you will see out of a NA 3 rotor is 240 foot
> pounds
> and it is orders of magnitude smoother than a diesel engine. Gear sets
> are
> designed around torque. The amount of HP they will tolerate depends on
> how
> cool you can keep them.
>
> The only thing I don't like about Tracy's PSRU is it uses high pressure
> hot
> engine oil to lube it. If it had all roller or ball bearings it could
be
> lubed with a separate oil supply fed through a small oil cooler and
> recirculated at low pressure. Gear lube designed for the job could then
> be
> used.
>
> Synthetic oil such as Mobile One will help. Regular engine oil breaks
> down
> around 220 to 250 F and the temperature of the oil in the line contact
> area
> of any gear set can easily exceed that temperature. That local hot spot
> oil
> is then combined with the rest of the oil in the gear box so it will
not
> show up in the measured oil temperature directly. Mobile One, according
> to
> my half hour oven test, does not break down until about 400 F to 500 F.
> You
> can run this test yourself. Put a teaspoon amount in a small can in
your
> kitchen oven when the wife is not around.
>
> What you can do with Tracy current system to improve it is add another
> small oil cooler in the high pressure line from the engine going to the
> gear box. The back lash is also a function of the spline fit or wear as
> there are several splines in Tracy design. Here is a design that does
> away
> with all splines. The sun gear is attached to the damper plate
directly.
>
> Keeping track of the oil temperature exiting the gear box is another
> option.
>
> The vibration is normal with Tracy's damper. It is the gear box over
all
> torsional stiffness resonating with the rotational inertia of the prop.
> The lowest idle RPM is a function of the shore hardness of the rubber
> bushings used in Tracy's torque damper. Softer rubber bushings will
lower
> the resonant frequency. I suggest silicone rubber bushings as they will
> tolerate 500 F while regular neoprene is limited to about 200 F.
>
> It won't hurt the engine to idle it above 1800 RPM. Your prop RPM with
> a 2.85:1 PSRU of course is only 631 RPM which is lower than the idle
> speed on my O-470.
>
> --
> Paul Lamar ...No rotor no motor.
> Paul,
>
> "HP can vary over a wide range depending on how it is tuned. A p-port
> or turbo can drastically increase the HP with little or no weight
> penalty."
>
> Wouldn't it be better to just peripheral port the engine as 75% of 400
> is more hp than 75% of 300 hp. And it would be lighter and much
simpler.
>
> Mark
>
> That is the simple way to go no doubt. But up in the real high
> flight levels you might still need a turbo. I think Steve Veach is
> on to something with a Lancair 320 turbo 2 rotor. That could be
> a very fast combination up high. Perhaps as much as 300 MPH.
> I thinking of selling my Kis Cruiser kit and my C182 and
> buying a flying Lancair 320.
>
> Paul Lamar
Concerning in flight failures - they happen even to the federally blessed
birds:
http://www.aero-news.net/news/genav.cfm?ContentBlockID=91b77742-7f20-4476-9787-acfec306c5bc&Dynamic=1
Cheers,
Matt-
Matt,
Yes, how well I know.
Mark
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