Recommended Props
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Always check and
tighten prop bolts
before each flight!
Loose prop bolts allow prop movement,
which will shear the bolts.
•
Always use the correct length prop bolts. If a spinner back plate is not used, the prop bolts may be
too long and can bottom out in the hub before they fully tighten against the prop washer.
•
The DA50 has a very wide power band. The "normal" peak operating rpm is 6,400 to 7,400 rpm.
While special break-in props are not required, be careful to not overload the engine during break-in.
•
Some recommended props are:
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Wood: 20x12, 22x8, 23x8, 23x8, 24x8
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Mejzlik Carbon: 22x8, 22x10, 23x8, 23x10
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Mejzlik Carbon 3 blade: 20x12, 21x11.5
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A general rule of thumb for good flight performance is the larger and/or heavier the plane, the lighter
the prop load to allow the engine to create more horse power. On a lighter/smaller/cleaner airframe
horsepower requirements are not as critical. You may enjoy the benefits of a larger prop disc for
better down line braking, torque rolling, etc.
•
Smaller diameter props with more pitch, especially 3 blades, can reduce tip speed and noise.
•
Always use a drill guide to drill your props. We normally drill from the back side first, then again from
the front to insure the screws don’t bind in the holes.
•
Always check the balance of your prop
•
For safety, we recommend painting the tips of your props (front and back) with a bright color,
especially on black props.
•
Never use a damaged or repaired prop, or a prop that has struck the ground or any other object.
Damage that can be hard to see could turn into disaster when turning at thousands of RPM.
Fuel and Oil Mix
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We recommend Low to Mid octane pump gas, such as 89 to 91 octane for your DA50. If a tuned
pipe is used, we recommend Premium/Hi octane pump gas.
•
We recommend purchasing your fuel from “name brand” gas stations. We have seen problems with
cheaper gas from some discount type outlets.
•
We recommend filtering your fuel between your fuel container and your plane’s fuel tank. A high
flow filter, or clunk/filter, between the tank and motor is also a good idea.
•
Make sure the plane’s tank is well vented and the fuel clunk moves freely.
•
Use of any other fuel or additives such as nitro formulas, aviation gas, white gas, etc., can
harm the motor and void the warranty.
•
Do not use silicone sealers on the fuel system. Gas can break it down and carry it into the carb.
•
We recommend a high quality synthetic oil. As for the brand of oil, there are many good ones on the
market. Some oils, and their mix ratios, that Desert Aircraft recommends are: Red-line Two Stroke
Racing Oil (40 to 1), Motul 800 (50 to 1), and Stihl HP Ultra (50 to 1). These oils can be found at
most motorcycle or chainsaw shops.
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