I TALKED TO ZENITH JUST 3 DAYS AGO ABOUT THIS SAME THING,SENSENICH 3 BLADE IS WHAT THEY TOLD ME.

HEY VOLKER,

I have a Warp Drive on my 701 with a 912s. The plane weighted in at 620# dry and it feels like a rocket on take off especially after flying Cessna's. A 701 with a 914 will be a bad boy/girl. My Warp Drive is set at 11 degrees which seems to work well, it has a nickel edge on the blades and is easy to maintain. The 701 can only fly so fast with all of the drag but that extra HP will sure make it get up and go!

Good Luck!

Volker,

I have a Warp Drive Three blade composite with leading edge nickle blades.  After talking with the good folks at W/D I used a 68 in dia setup set at 13.5 degrees.  This is with the 912ULS.  What I was looking for was after leveling at cruise altitude of about 5000 ft I would get around 5500 rpm full throttle - I get from 5500 to 5590 all that said it works very well and I am so satisfied that I don't change it. Google Phil CH 701 and look at the

take off video - that was a long time ago and I wasn't trying to max perform - but it gives a look at the acceleration...basically I shove the trottle to the wall count to three and pull back...whee!

Still grinnin

Phil

Stats:

CH - 701

empty wt 594

cruise rpm 5000... IAS low - mid 80's

TAS high 80's to low 90's at 5500

field elevation msl 3660

ambient temps up to 100 f

density alts vary up to 10,000 ft in summer

In the late 90's, through 2004, there were 3 of us in the U.S. that had 701's w/914 turbos. George Wood, Grand Jct., Colo. (ex Korean fighter pilot), as visited him; Danny Defulici-Gold 701 on floats in Florida; Danny well known via Chip Irwin + worked w/Chip in Sierra Miesto, Czech Rep.. bringing Zenith on barges to Florida, final assembly + N # there. I installed the 914 Turbo in the late 90's, being the 3rd, as the 912S/ULS was not available + opting not for the 80 ponies due to altitude. Point- Danny + I used Warp, 3 Bl. square tip 70". I had 11" clearance to ground, not opting for 72" for chuckholes in grass, etc. On a cool day, indicated = 2,050 ft. on climb. I modified fiberglass  cowling top for carb. clearance + side panels for airflow, + ceramic coated exhaust. As you are were mercury rises, do the same on your cowling, i.e. get the heat out. 70" Warp sq. tip is what you need.

The prop I am now using and am putting on my new 701 is the warp 3 blade,set at 11.5* for max take off , as in the float 3 second video, there are faster props available , but none stronger , I have blown snow with mine ,also many water take offs, with no damage, the foam core props wont take the same abuse , if you are not back country flying any prop will work , the turbo motors need a variable pitch to get their full potential , ...BOB

Volker & Bob, as I posted previous lengthy reply recently-I did not consider a variable pitch prop to get full potential, as the airframe parasitic + induced drag compromised any increased airspeed. Then, the the LSA rules came out, w/multiple rules - one being no variable pitch props. As Volker lives elsewhere, rules there most likely don't apply. I did use an electric pitch 66" Magnum 2 bl. warp on 912ULS on another current E.A.B. I have, & effective. Had toggle switch on console.  However, it weighed 22# 4 oz.w/ ULS spinner. The engine can handle it, but it's heavy on the geqrbox, dog ears/legs. Ronnie Smith + Phil Lockwood told me to change it....it would fly alright, but someday wouldn't start.  The 68" 3 Bl. tapered tip w/nickel leading edges = 10# 2 oz. This also allowed my to move my battery forward 4-5 ft. for accessibility, charging.

WARP prop 68 - 70 inches dia. 3-blade.

I use a WARP 3-blade 68" dia on my CH601HD

I use a WARP 3-blade 72" dia on my CH750.

I am using a prototype from built especially for the 914 ( they may be in production by now ) on my 914. Beautiful white prop.

It replaced a constant speed prop.

That should read ----- " from Sensenich " 

 after discussing the matter with Roger at Zenith I purchased a 68" Sensenich 3 blade however I can not give you any performance data as my 701 is not flying yet.

Especially with the 914 you'll loose out significantly on performance unless you use a constant-speed, or at least a pilot-controlled variable pitch propeller.  In my opinion this is relevant to any aircraft, not just to lower drag designs. 

One could argue that you really don't need all the performance available from a 914 on an airplane like the 701.  And the sensible answer would be "it depends on your flight profile."  And of course, why buy a 914 if you don't need one?  Certainly on a 701 the 912S with a properly pitched warp three blade provides fantastic agility if confined to moderate altitudes.  Warp blades are heavy but very strong.  Three of them put the inertial load at the high end for Rotax gearboxes.

On my 701/914, I use an Airmaster constant-speed with two Sensenich blades.  The two Sensenich hollow blades save a few pounds compared with three solid Warp blades.  My own flight profile is varied and quite demanding.  I have about 250 hours on this 701/914/Airmaster/Sensenich flown from short, high-altitude, grass strips, sometimes heavily loaded.  I've taken this airplane up to 23,000ft, and down to sea level.  Experience has shown this engine/propeller combination does a good job for my varied flight profile and high altitude.

Philip Fried

Hi Everybody, thanks for all your great suggestions. You've confirmed what I've been thinking all along - 3 blade 70" warpdrive. It's good to be part of the zenair family. Volker

Hello All

I'm thinking about making a turbo conversion for the 912UL and Felipe sparked in me the following questions:

Does anybody have experience with using a pilot controlled variable pitch propeller with a 914, or a 912UL turbo conversion? Does it distract the pilot too much when manually adjusting for performance on take-off ?(float flying) and How much loss of performance can you expect if keeping the pitch setting for a set rpm on take-off?

Also, when measuring the prop-pitch, do you measure the angle at the very tip of the blade?

Last but not least:

Anybody have experience flying a CH701 on floats with a Rotax 912UL (80HP) and an in-flight adjustable prop?

I know...lots of questions..:-)

Thanks

Dietrich    

What I meant in my last mail is: the difference of performance between governing for constant speed,.. or manually leaving the prop-pitch setting for best take-off during the whole take-off run with a float plane.

(Just to find out if there is a significant difference)

Cheers

Dietrich

Dietrich - As I previously addressed this post, review. However, no, the electric variable pitch IVO 66" Magnum was not a distraction-posted installed a toggle switch on center console. Just set for max T.O. RPM. Cruise-throttle back to cruise RPM, then adjust cruise pitch. 2) Most prop MFG's recommend setting pitch 2" inward from blade tip. The prop flange should be plumb. Often on 2 E.A.B.s currently, I deflate nose wheel, cut 5' 6" 2x6, or 2x8 under tail to obtain the flange to be plumb via level. 3) On a tapered tip, the pitch @ 2" inboard from tip will be 1.5 degrees different than a sq. tip. On my 701 w/turbo as stated, I did not use variable pitch due to the high drag-I just had the same power @ high altitude, would cruise 80-85 mph. As you are in Switzerland, you need full RPM + climb.

Scott, Thank you for your info. Actually, with the pilot controlled variable pitch propeller I had the mechanically adjusted pitch control in mind, as GSC offers with the GTA Propeller hub. This has a control knob in the cockpit and with each revolution you optain one degree of propeller pitch. So there is no governor which maintains a pre-set constant speed and while I would watch for airbox temperature, lake trafic and debris I have my concenrns about adjusting the mechanical knob to keep optimal rpm. But as you say Scott, I have a feeling that I won't get much out of the adjustable pitch if the plane stays as draggy as it is :-) 

I do not know of anyone flying w/80 ponies + floats. Hopefully some one will reply. There is a kit out, but $4,200 U.S.D., increases your 912 from 1211cc to 1484 + comp. from 8.75 to 9.5. There are currently 5 flying in the U.S. w/150 hrs. The 1484 is more than the 1350cc in the  stock 100 ponies. You/ve not stated your home field elev. in Switzerland.

Check out Koolprop site. I've got a 69" on my 701 Subaru 100hp.

Scott, Field elev. in Switzerland is 2'146 ft (grass), at this time I'm spinning a 3-Blade Warp 70" tapered the pitch is set at 9 degree at 2". If I remember correct: at MTOW and best rate, I get 5400+ rpm up to about 5'000ft. I know that I should set for max rpm, however the prop pitch seems already so low for cruise  (high rpm). I have another 3-blade Warp 68" squared...maybe that is a better suit for the 80 horses (we prefer horses over ponies :-)

My plan is to export this airplane to Canada in 2016 and convert it to a floatplane. First flying in the east and then take it into the Rockies for higher altitudes. So your mention of the Kit to increase the 912 from 1211 to 1484 sounds very interesting (as to the turbo alternative). Do you have any contacts for this application?

Thanks Leonard...interesting figures!

Per your question for contacts on the HP conversion, don't have his e-mail, (208)-891-4041 M.S.T., Mark Ferkin.