Zenith CH 650 Performance with UL Power engine

We finally had the chance to document some basic performance numbers of our new CH 650 with the UL Power UL350iS engine.  Yesterday was a beautiful autumn day so Zenith demo pilot Roger and I took the CH 650 up for a few flights.  Our new demo airplane is equipped with dual Dynon SkyView glass panel displays so I took my video camera to document the flights. Below are various screen shots (we'll edit the video together when we get the chance).

The CH 650 at Mexico Memorial Airport (KMYJ): Elevation 822 feet, Temperature: About 10-deg. C (~50 deg. F.)

Take-off distance is surprisingly short at 300 - 400 feet (video obviously shows this better) with the wheels lifting off at about 45 mph.  The UL350iS engine is equipped with a ground-adjustable 65-inch Whirl Wind propeller.

Here we climb at about 1,000 fpm with an airspeed in the low nineties, which is a comfortable climb speed with good over-the-nose forward visibility (a steeper climb angle yields about 1,200 fpm climb rate).

Here we level for cruise at 2,100-ft ASL, indicating 138 mph.  Notice the TAS and GS below the airspeed "dial" on the left.  Below is the 7-inch Dynon SkyView display (in front of the right seat):

Cruising at 136 mph in a slight left bank.  Here's a near full panel view:

We then continued to climb to 5,000 ft.

Notice that even in the direct sun the SkyView screens are bright.

Here we demonstrate some slow flight.  With flaps and 2,000 rpm, we maintain altitude at just 44 mph indicated airspeed (though notice the nose up attitude).  Slow flight handling is nice, and stalls are very predictable.  
With the UL350iS engine's FADEC system there in no carburetor heat or mixture control!

With some flaps, approach speed is about 60 mph with excellent forward visibility.  Ground roll is barely longer than take-off at a few hundred feet.

We're very pleased with the Zenith CH 650 aircraft with the UL350iS.  It's a dream to fly and offers outstanding visibility and excellent flight characteristics, while being simple to operate.

We invite you to try it out for yourself!  Contact us to schedule a demo flight in this nice aircraft.


Sebastien Heintz,
Zenith Aircraft Company


(We plan to present the above in video format).

Views: 21033


You need to be a member of Zenith Aircraft Builders and Flyers to add comments!

Join Zenith Aircraft Builders and Flyers

Comment by Sebastien Heintz on November 14, 2011 at 4:05pm

The FWF kit is basically developed.  We're just waiting on the final cowl from the fiberglass shop.  I think engine lead time is several weeks.  Details, see www.ulpower.net

Comment by Joe McGough on November 12, 2011 at 11:16pm

Any idea how long before you will have the FWF kit for the 750 ready. Also, any guess on lead time. Thanks, Joe

Comment by Sebastien Heintz on November 12, 2011 at 2:58pm

In response to Steve Smith's notes we've been cruising the low-wing CH 650 with the UL350iS engine at different RPM settings to look at economy of operation.  In these next two photos we power down to 2,250 RPM, which is 100 HP according to the UL Power UL350iS engine performance chart.

At 2,250 RPM with fuel burn indicated at 4.0 GPH:

...and here indicated fuel consumption is all the way down to 2.9 GPH, though it seems to average closer to 4 GPH.  While not fast at this RPM setting (I think we could get more speed here by playing with the prop pitch), it's very economical and the aircraft handles nicely in the low nineties:

Next, we throttled up to 2,500 RPM, about 112 HP according to the chart, with fuel burn still less than 5 GPH.

We'll continue to fly the aircraft and record performance numbers, and share our photos/videos and observations, and we appreciate your comments. 

We're really enjoying this CH 650 airframe/engine combination!

Please note that the above are my observations, and not an official performance / flight test report.

Comment by Geoff Klestadt on November 8, 2011 at 6:24pm

Just wondering if the fuel flow figure is accurate and comes from a differential fuel flow meter? We aren't including the fuel return  by any chance?

Comment by Dan Watters on November 7, 2011 at 6:58pm
It is a new engine. With time I would expect the fuel burn numbers to improve a bit. What would put me off this engine is the almost $30K cost with the FWF kit. I could wait for the dollar to improve against the Euro but by then we will all be flying around in anti gravity tennis shoes.
Comment by Sebastien Heintz on November 7, 2011 at 10:34am

Gus Warren / FlyWithGus.net first flew the CH 650 with a UL260i, (which is a better comparison to the Rotax 912 series engines).  Here's his post from April 2009, Are you ready for Sun 'n Fun?, in which he reported:

Keep it light and clean and and it is better, also the fuel injection saves a bit of fuel per hp. Real world I am seeing 125 mph at less than 4.5 gph, it will do 135 about 5.3gph. Best is about 80 and 2+ gph. So, yes it does burn 3.2 per hour, and a lot more and a lot less. Have to relate GPH to speed, but even there can be great variations due to different airframes even of the same design.

We flew together that year to Oshkosh and I recall he was getting both excellent performance and efficiency with the the UL260i engine in his CH650.  That's what got us interested and enthused in UL Power...

Comment by van Cutsem Francis on November 7, 2011 at 4:32am

Hello Sebastien,

You are all speaking about the UL 350 delivering 130 HP.

A rotax 912 is given for100 hp, what about the UL260 for the 650? I suppose that the fuel burn will be less or equivalent

for a 912.

My 601XL with a 912, fuel burn is 4.7 GL at a mean speed of 120 mph


Comment by Stephen R. Smith on November 6, 2011 at 12:08am

My hope is that the UL350iS motor is fuel efficient when operated in what I think of as “normal flying” mode.  What the motor does flat out is not too important for me because I don’t fly like that for more than the 3 to10 minutes it takes to get up off the ground or over something that is in my way.

I think the fuel burn numbers posted so far are respectable for the stated speed in a Zodiac airplane.

By way of comparison, today I flew my Jabiru-powered Zodiac at full gross for 2.8 hours.  My average fuel burn was 4.3 GPH.  Average speed was 92.9 MPH.  Average RPM was 2,386.  This for me is typical flying in my Zodiac.  Yes, it will go faster but for me the “fun meter” does not go up with speed, unless I am buzzing the field or something like that.

I love having the reserve power to pull my plane over the mountains fully loaded.  I like knowing I can take off from ANY paved airstrip in the US fully loaded on a hot day without bothering to check runway length, density altitude etc.  That’s what I want the power for.

The Jabiru is powerful, smooth and pleasant (most of the time).  I hope the UL motor is all that and also more durable than a Jabiru.  Time will tell.


Comment by Fred Wellman on November 5, 2011 at 4:04pm
PS.  A Rotax is more likely to burn about 4.5 to 5 gallons at 115 mph.  (A least according to the three RV-12s that I have flown in)
Comment by Fred Wellman on November 5, 2011 at 4:02pm
I agree with Joe.  At this point, 7.6 gph isn't terrible at 140 mph (actually I think its pretty good). I think that experimenting with a different prop can probably bring that fuel burn down a bit further.  This is exactly the info that I was looking for.  Thank you for posting it.  Now I can make an iformed decison regarding power plants.

New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.

Custom Upholstery Kits for your Zenith Aircraft:

Zenith Vinyl Upholstery Kits

Zenith Apparel from EAA:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

How to videos from HomebuiltHELP.com

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit HomebuiltHelp.com for the latest DVD titles.

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Golden Eagle Aviation

Pianosa Flying Farm

Aircraft Spruce & Specialty for all your building and pilot supplies!

© 2022   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service