Hi! Michael
In the absence of William Mills and David Joyce I can pass on to you
some results of comparisons which they did on the Woodcomp propeller.
I know that William has the scimitar shaped blades on an SR 3000. but
his engine is the Rotax 912S . ..he also has the control unit by Mark
Burton and I know it has a very fast facility to go into "beta" mode
(reverse thrust) which I know William makes good use of on his very
short landing strip.
Unfortunately William and David have just left on " The Last of the
Summer Wine Tour" round France so will be about a week before returning
and then on or about the 17th Sept. they go on the Canaries Trip for 10
days.
However the chart I'm providing will serve as a point of interest until
you can get a direct dialogue going with them either between the
aforementioned trips or after.
Bryan Allsop also has a Woodcomp Propeller but I know it has the
straight blades on a 912S as has Davids but David has the Rotax 914.and
I think his propeller is the 2000SR.
Mark Burton who has developed a superior controller for the Woodcomp may
be able to discuss some features with you in their absence. His e-mail
address is:-
Mark Burton markb@ordern.com But I believe he is also intending to do
the Canaries trip as indeed I will be with Bryan Allsop.
I attended a conducted tour of the Kremen/Woodcomp factory with the
group which went on the first "Six Nations Tour" and I am pleased to
confirm that they have a very dedicated and professional team working to
exacting standards producing propellers with excellent quality at very
advantageous prices.
Best regards
Bob Harrison.
Herewith the document mentioned above....I'm not sure, however, that the
tables are for the scimitar 3000SR blades though.
The Cedars, Glascoed, Pontypoool, Gwent. NP4 OTZ
Tel: 01495 785499
_____________________________________________________________________
Vodolska 4, 250 70 ODOLENA VODA
CZECH REPUBLIC
2nd June 2006
SR 3000/3 - SR2000/3 Performance Comparison Tests Results
Flights carried out on 31st May 2006
Conditions of the Flight Tests: -
* Both Propellers were fitted to Europa Monowheel Classic Reg.
G-HOFC
* Both test flights were carried out with identical pay loads
(near maximum all up weight) and the fuel used on the first flight was
replaced before the second flight was made.
* The bugs gathered on the airframe on the first flight were
removed before the second flight was made.
* Both sets of blades were clean before flight.
* The test flights were made between 7,000 and 7,200 feet above
sea level where the air was absolutely stable and the wind speed was
negligible.
* Both flights were carried out in the same area of uncontrolled
airspace and with approximately the same headings.
* Fuel flow tests at the various indicated airspeeds were carried
out at target 5,000 rpm engine speed to allow for the restriction on the
SR 2000 reduced coarse pitch limit at high throttle settings.
* ** Engine oil temperature was 10 deg C higher for the second
takeoff.
* QNH was 1027 mb and OAT at ground level was 12 deg C and at
7,000 ft was 1.5deg C
* Pilot: William Mills Observer: David Joyce
SR 3000/3
SR 2000/3
Takeoff time 09.15 hrs
Takeoff time 10.50 hrs
Landing time 10.15 hrs
Landing time 11.40 hrs
Ground run to T/O 183 yards
Ground run to T/O ** 242 yards
Climb from 1100 to 2100 ft 73 secs
Climb from 1100 to 2100 ft ** 71 secs
Full power climb rate @ 5,500 rpm
and 74 Kts between 3,500 /4,000 ft 1000 ft/min
Full power climb rate @ 5,500 rpm
and 75 Kts between 4,000 and 4,500 ft 950 ft/min
Max airspeed @ 7,000 ft and 5,500 rpm 145 Kts
Max airspeed @ 7,000 ft and 5,500 rpm 141 Kts
Fuel flow @ max airspeed 22.4 L/hr
Fuel flow @ max airspeed 22.7 L/hr
Fuel flow @ 100 Kts IAS 11.4 L/hr
Fuel flow @ 100 Kts IAS 13.4 L/hr
Fuel flow @ 110 Kts IAS 14.1 L/hr
Fuel flow @ 110 Kts IAS 14.8 L/hr
Fuel flow @ 120 Kts IAS 14.4 L/hr
Fuel flow @ 120 Kts IAS 15.3 L/hr
Fuel flow @ 125 Kts IAS 16.3 L/hr
Fuel flow @ 125 Kts IAS 16.8 L/hr
Fuel flow @ 130 Kts IAS 17.4 L/hr
Fuel flow @ 130 Kts IAS 18.2 L/hr
Conclusion: The SR 3000/3 has a better all-round performance than the
SR 2000/3. Normally, the target rpm for high cruise speeds is between
4,500 and 4,700, which would give a slightly better fuel consumption,
but for comparison purposes 5,000 rpm was selected to allow for the SR
2000/3 reduced coarse limit. The average fuel flow between the speed
range of 100 to 130 Kts was 14.72 L/hr for the SR 3000/3 and 15.70 L/hr
for the SR 2000/3, which gives a fuel saving of 6.24%. However, the SR
3000/3 result at 110 Kts appears high when plotted on a graph and it
might be accounted for by the aircraft flying at the back of the
lift/drag curve causing excessive drag. If this is corrected by
interpolation to say 13 L/hr at 110 Kts, the average fuel flow for the
SR 3000/3 would be reduced to 14.5 L/hr, which gives a saving of 7.64%.
The ground run prior to take-off is 24% shorter with the SR 3000/3.
...............................................................
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of
m.grass@comcast.net
Sent: 07 September 2006 00:03
Subject: Europa-List: Woodcomp CS curved propeller type
Hi all,
I am just about ready to order my cs prop. I was set on the Woodcomp.
The company came back with the question "curved or straight" blades!
My question now is: Did anybody on this list has some comments on the
new curved design from Woodcomp? Attached you find pictures from the
curved and straight blade design. I could not get good advise so far
which would be better for my Tri Gear Europa XS with a 914. Are there
any performance data available?
Thanks in advance
Michael Grass
Europa XS TriGear, 914 Rotax
Detroit, Michigan
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