Back-to-Back Propeller Test on a Zlin Norden 916iS: DUC vs Catto vs E-PROPS Glorieuse

On Facebook, there was a very interesting field-test report comparing 3 constant-speed propellers on the same aircraft (ZLIN Norden), with the same Rotax 916iS engine, all tested back-to-back during the same morning.

This type of direct comparison is particularly valuable, as the test conditions remained as consistent as possible between the 3 propellers.

Test Conditions

All three propellers were hydraulic constant-speed models.

• Engine: Rotax 916iS
• Outside temperature: 90°F / 32°C
• Density altitude: 4,000 ft
• Cruise setting: 5,500 RPM and 40 inHg manifold pressure
• Weight / Price: complete installation, including spinner, spacer and bolts
• Aircraft: Zlin NORDEN
• Tests: performed back-to-back during the same morning

Results

3- Blade Propeller	Diameter	Complete weight	Static thrust	Cruise speed	Public price
DUC Flash 4	80 in	24.5 lb	575 lb	109 mph	$12,800
Catto	82 in	23.4 lb	695 lb	109 mph	$21,100
E-Props Glorieuse	82.7 in	9.4 lb	634 lb	116 mph	$9,800

Weight, Thrust and Cruise Performance

The results highlight some significant differences between the 3 propellers.

The Catto produced the highest static thrust during this test, with 695 lb, compared with 634 lb for the E-PROPS Glorieuse C9 and 575 lb for the DUC.

=> But static thrust is only one part of the overall performance of a propeller.

At the same cruise setting of 5,500 RPM and 40 inHg, both the DUC and Catto reached 109 mph, while the E-PROPS Glorieuse reached 116 mph.

=> That represents a 7 mph (11 km/h) increase in cruise speed under the reported test conditions.

The difference in weight is even more striking:

• DUC: 24.5 lb
• Catto: 23.4 lb
• E-PROPS Glorieuse: 9.4 lb

The complete Glorieuse installation was therefore approximately 60% lighter than either of the other two propeller installations tested.

And What About Price?

The comparison becomes even more interesting when public prices are included:

• Catto: $21,100
• DUC: $12,800
• E-PROPS Glorieuse: $9,800

The E-PROPS Glorieuse is therefore not only the lightest propeller in this comparison and the one that achieved the highest cruise speed, but also the least expensive of the three.

At the stated public prices, the Glorieuse costs approximately 54% less than the Catto and 23% less than the DUC.

The Results at a Glance

With the E-PROPS Glorieuse 82.7-inch, this back-to-back test recorded:

9.4 lb complete weight
634 lb static thrust
116 mph cruise speed
$9,800 public price

The test is a good illustration of why propeller performance should not be evaluated from a single figure such as static thrust alone.

Weight, static thrust, cruise performance and price all contribute to the overall picture.

In this particular back-to-back comparison, the E-PROPS Glorieuse combined by far the lowest weight, the highest cruise speed and the lowest public price.

Many thanks to the Michael Busenitz for taking the time to perform this very useful comparison and for sharing the results. 🤩 👍

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Comments from Pilots and Readers

The original test results generated some interesting reactions from pilots and aircraft owners on Facebook:

J.M.
“Don’t want to say I told ya. But I told ya! Oh, and you forgot to add the prices. I love E-PROPS Propellers. Thanks for sharing!”

T.H.
“E-PROPS all the way! Plenty of good thrust and amazing cruise.”

M.D.
“E-PROP: more speed and way easier on your Rotax gearbox. Hard to believe just by looking at them. I have two aircraft with them on, and they are also quieter.”

E.W.
“9.4 lbs. That’s amazing.”

Z.K.
“The Catto and DUC seem heavy for a Rotax. Do they come in under the MOI?”