John and his partner have been working on this for a long
time.
Something like
20 years. Just recently did they get it flying. The first
thing
that
happened was they lost an apex seal. Probably due to
detonation.
They over hauled the engine and then the turbo let go. Nothing
new here
as that is probably about the 8th 2nd gen turbo to let go. The
turbo
caught fire when it failed. Fortunately not a lot of
damage and
John
was able
to glide to a safe landing back at Camarillo. The turbo is
being
modified
to Dave Leonards spec. Hopefully we will get a report
after his
5000
to 6000
mile trip.
I was unaware they were flying. The last time I saw the
airplane was
about five or six years
ago. If I had known about it I could have warned them
about the
detonation
and the 2nd gen turbo. You MUST monitor the intake charge air
temperature and keep
it below 140 F or you WILL get detonation sooner rather
than later.
We have known about and discussed the 2nd gen turbo problems
for at
least two years
and maybe three.
The PSRU is a home made belt unit built according to Blanton's
plans. The ratio
is 2:1 so they need a lot of boost to get the HP. They had
the
large
pulley custom
made by a broach shop in LA.
They are running 50 inches Hg MAP for take off and 45
inches of
HG MAP for climb
out. Max rpm for climb out is 4500. Static engine RPM is
5100
RPM.
The turbo is working hard. Cruise is 4000 RPM with 42 inches
of Hg.
TAS is 160 MPH. Fuel burn on take off and climb out is about
7.5 gallons
an hour extrapolated from the last short trip when the
turbo failed
so they are not making very much power despite the high
manifold
pressure. The manifold itself is stock without the mass
air flow
sensor. Just the stock TB. You can get away with that if you
use a belt
drive as the engine sits lower. They are using Tracy's EFI
unit
instead
of the stock computer.
During prior cruise flights they were burning 4.6 to 5.0
gallons and
hour.
More about the cooling system shortly.
Did I get all this right John?
Paul Lamar ...No rotor no motor.
Courageous, but it seems that people insist on working too hard on
things that they don't need to and skip taking care of some
important
stuff. Buy the PSRU. Build (or buy) a P-Port.
_Everyone's_
time is
worth something.
I think all new installs need to run on a test stand at high power
settings - takeoff power - for at least 50 hours . If not a
test stand,
on the chained down airplane with fan cooling. People make too
many
rosey assumptions about how much better things will go once
there's
slipstream cooling air through the system. I'd make exceptions
to this
if an install is a
_direct_ copy of another which already works
reliably. In that case, only spend 25 hours on the
stand. There are no
direct copies!! Hah. :) Lots of useful stuff will be learned
in the
process of making it run well on the ground. It's a tough pill to
swallow because lots of builders really want to be fliers instead.
I don't think they're undergeared so much as overpropped. It's
not all
that unusual for a LongEz to cruise with the prop at 3000RPM. They
aren't supposed to have props with diameter greater than 62"
(though
some aircraft do), so I think 3000RPM is no big deal, and that
would
allow a 6000RPM engine speed. They need less pitch, less diameter,
and/or a better prop airfoil. Do these guys have any other EZ
experience? Oh wait, are they running an IVO or Warp drive - I
think I
can see it in one of the pics. How fast are they allowed to
turn? And
at what RPM does that blade get really inefficient?
Matt-
I think you are being a bit hard on them Matt. A lot of these
decisions
were made over ten years ago. Probably before one could buy a PSRU
off the
shelf. These guys are true rotary engine pioneers along with Yvon
Cournoyer
and Ken Welter with a similar belt drive PSRU's. We have come a
long
way since
1997. Turbo chargers have advantages at high altitude (12K to 14K)
cruise.
Here is the cooling stuff. The original configuration was a
real thick
(5 or 6 inches) custom rad core in the nose. I did not think it
would work when
I first saw it and of course it did not work. They adopted the
super
simple, super
quick under the fuse mounted heat exchanger with Kays & London
wedge
shaped diffuser. Works like a charm. Super slick cowl. So far
water temp
is 205 F take off and 185 F cruise.
Oil cooling in the nose is two Earl's supply oil coolers back to
back in the
cross counter flow configuration. In other words the back cooler
gets the
hot oil first. Oil temp is 205 F on take off and climb out and
192 F
in cruise.
--
Paul Lamar ...No rotor no motor.
Yeah Paul, you're right.. I was at work when I wrote that. I still
think they are over-propped..
Matt-
They could be. We will see when they get the new turbo charger.
One bit of evidence against that is the 5100 static RPM.
Perry Mick, what is your static RPM again? I think the Andrich turbo
Long EZ MPG
might work out to be exceptional. It is showing some signs of that
already.
John and I discussed the reasons for the new 16B. I think we both
agree Mazda
made it larger with more torque so they could raise the RX8 axle
ratio and
cut the 80 MPH cruise RPM to reduce engine friction. What would be
ideal of
course is a constant speed prop.
--
Paul Lamar ...No rotor no motor.
I just want to reiterate my apology for being down and grumpy on the
Andrich's LongEZ - my last apology was more of an excuse, really (lame).
The Andrichs have a real, flying rotary powered airplane. That has
obviously taken a lot of smarts, ingenuity, and a ton of effort. I
applaud their capability and dedication and wish them the best of luck.
I hope we are able to keep abreast of their development process and
contribute good ideas when we can.
Best regards,
Matt-
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