Introduction


Koolprop



Being an aviation engineer and professional light aircraft designer, I use and compare different propeller brands from 1987 year. I used composite, wooden, plastic and metal; constant pitch, ground and in-flight adjustable; constant and variable RPM propellers not only for aircraft but also for hovercraft, airboats etc. Working in Europe and North America, I think I tried all propeller brands.
Many amateur builders and pilots underestimate the importance of the propeller for their crafts. If they are not happy with their aircraft performances, noise or vibration, they think about changing the engine for more powerful one, redesigning the motormount, muffler etc. But the problem can be fixed much easier very often. I always advise to start thinking "from the prop". Is it a really efficient one? Is it well matched to your engine and craft? Is it in a good shape, well balanced?

My experience - a good correctly chosen and installed prop can fix such problems in most cases. To change the prop is much easier, faster and cheaper than changing the engine, but the effect can be the same or even better.
We are able to help you with the right, optimal propeller choice and supply the best propeller regarding its quality, efficiency and price. If you build a new aircraft, airboat or hovercraft and not sure which prop you need; if you want more thrust, shorter takeoff, higher cruise speed, lower gas consumption; if you are tired of the noise and vibration - contact me. I promise, you won't be disappointed!


ROSSIprop - efficient, strong, affordable.


General information


ROSSI Variable Pitch Propeller (VPP) is intended for Experimental light and Ultralight aircraft, airboats, hovercrafts, snowmobiles etc. The hub has a special mechanism allowing to change the prop pitch on a running engine. It allows to keep maximal prop efficiency, thrust an fuel consumption for high airspeed range. Reverse (negative pitch) allows to move the craft backwards. It can be useful for airboat, hovercraft, amphibian or float aircraft. Reverse can help to make a landing run shorter working as a powerful air brake.

Rossi VVP can be ordered 3 blade and 6 blade version, left and right hand rotation, pusher and tractor. 2 and 4 blade hubs will be ready soon. 4 different blade models 69"-73" can be installed in VPP hub. The hub has a special control rod going through a hollow gearbox/redrive shaft. It can be connected directly - mechanically or electrically (through a linear electric motor) with a control lever/switch in the cockpit.
Short technical description of this prop is HERE.

There are 7 blade models of ground adjustable ROSSI propeller, from 47" to 77" diameter. The blades have semi-scimitar shape similar to Kievprop and Aerolux, best set of airfoils. They are very strong, with polyrethane leading edge. Most blade models have the same root shape as popular Kiev, KOOL, Aerolux etc. models and can be used as their direct replacement, with KOOL spinners. They can be used for pushers and tractors, both rotation directions. The standard blade color is black, white - special order.

I fly my trikes with ROSSI props and completely satisfied. Very good thrust, low noise and vibration. Small diameter props are widely used for PPG, light PPC and airboats. The prop hub system with aluminum plates and clamping blocks allows to change the prop diameter, make your custom prop. You can order as many sets (blade + clamping blocks) as you need and make you own hub plates for up to 12 blades.

Standard sets of ground adjustable Rossi props, pitch protractor and different hubs are below. Each blade has the serial number and moment of inertia stamped on the root end. If you need a replacement blade, you can order it using these numbers.



 Rossiprop specifications.

- Diameter 48"-77"
- Maximum speed of rotation 2800-3500 rpm for different models
- Power of engine 18-260HP
- Polyrethane integrated LE protection.
- Hub type "Rotax" 582/912 75mm or custom made
- Manufacturer's warranty 500 hours or 2 years - Available in left and right hand rotation, for pushers and tractors.

Rossi standard set included 2-3-4-6 blades, hub, hardware and soft blade covers. Blade+cover+clamping block sets available too.
Design description + assembling and installation instruction for this prop is HERE.





KOOLprop - exceeds expectations!


General information


KOOLprop is designed and made for different airscrew driven vehicles: Experimental, Ultralight and Light Sport airplanes, trikes, airboats, hovercraft, autogyros, power parachutes, paragliders etc. All blade models are designed using computer technologies, then tested in a wind tunnel and in flight + passed special destructive tests. There are 20 different prop blade models for different applications, right and left hand rotation, pusher and tractor, straight and scimitar shape, from 47 to 78 diameter. You can use them with a lot of engines from small Simonini PPG 15-18HP to powerful Rotax 914 and Subaru-Suzuki-Honda autoconversions up to 200HP. Special reinforced blades can be ordered.
Finish is excellent black gelcoat, with white tips. Black blades are preferable for tractor planes - better visibility through the prop. The white tips make the running prop ends more visible to increase safety. White and 2 color (one side white, another one black) blades are available as a special order.





I can compare KOOLprop with Kievprop I was flying and selling before. Koolprop has exactly the same hub design, CNC machined from aviation aluminum allow and anodised. You can use your old Kievprop hub and spinner with Kool blades. There are some points making Kool preferable for me. They are both hand-made with highest accuracy but KOOL prop is made with carbon fibre + fiberglass composite instead of only fiberglass-made Kievprop. Koolprop blade is much more rigid, it helps reducing idle wobbling and slipstream interference vibrations. KOOLprop finish is epoxy gelcoat, not paint like Kiev, so KOOL surface is harder and smoother, more difficult to scratch. As Kiev, Kool has integrated strong leading edge protection, but it is made with stainless steel, not copper. It looks more beautiful (always shiny) and it is stronger than Kiev LE. This thick metal LE makes KOOL preferable for Amphibian and Float planes as well as STOL and Bush planes flying from unprepared runways - ideal protection against water splashes, tall grass, dirt, tiny rocks etc.


We sell and use KOOLprops for all trikes and powerplants made by Air Trike Enterprises from 2006. All KOOLprop users mentioned that KOOL is more smooth, silent, and provided better performances than their previous propellers. To see more pictures and read some feedbacks from pilots using KOOL props CLICK HERE.
Spare blades are available. If my customer brakes one, two or all blades, he sends me the type and serial # of the blade printed on its root, and Air Trikes supplies spare blades already balanced and matched to his blades. Spare blade orders are always highest priority!

There are 2 types of Kool blades - classical (straight) and scimitar. Which type is better? No simple answer...
Straight, classical-style blade is able to produce more static thrust with the same diameter. It can be important, if you are restricted in diameter, for example in case of PPC, PPG, airboat. Can be more efficient for low speed crafts, low prop RPM; preferable for planes with low prop-ground clearance flying from unprepared fields.
Scimitar-style modern blades are more efficient, especially for higher speed aircraft and high RPM powerplants. If you need maximal cruise efficiency, minimal level of noise and vibration - this is your prop. But these blades are more complicated in production so a scimitar set of blades is about 100$ more expensive than the straight one.
Spinner is strongly recommended for tractor type airplanes. We have 2 sizes of carbon-fiberglass spinners: 8 diameter 9 length for the standard hub and 10.3" diameter 11.4 length which can be used for both standard and large hubs.





 Koolprop specifications.

- Diameter 47"-77"
- Maximum blade width 5.9"
- Maximum speed of rotation 2800-3500 rpm for different models
- Power of engine 18-200HP
- Stainless steel solid integrated LE protection.
- Hub type "Rotax" 582/912 75mm (4" special order)
- Available in left and right hand rotation, for pushers and tractors.

ATTENTION! This propeller is not recommended for direct drive engines without torsional dampers (Lycoming, Continental etc.)
Koolprop standard set included 3 blades, hub, all hardware, pitch protractor and soft blade covers. 2, 4, 5, 6 blade props are available too.
Design description + assembling and installation instruction for this prop is HERE.



Order information


KOOL and ROSSI propellers have highest quality and very reasonably priced. We are always ready to help you with the best propeller choice. If you need a prop - call us or better send E-mail with the following info: engine type, HP, max power RPM, reduction ratio, max possible prop diameter, rotation direction*, type of your aircraft, cruise speed. We usually have most propeller models in stock and can send the same or next day after your payment.
*Right-hand propellers rotate clockwise to provide forward thrust. Left-hand propellers rotate counter-clockwise to provide forward thrust.

For spare blade order, send us the numbers on the blade root - blade model and serial number (moment of inertia)

The prop can be ordered with carbon-fiberglass 8" and 10.3" spinner (strongly recommended for tractor applications) and different hub spacers. 4" (big) diam Rotax 912-914 shape hub can be ordered with reinforced blades.

6-blade prop. More than 3 blade propellers can be recommended if you have high power engine, slow rotating prop (high ratio gearbox) or prop diameter restriction.
Small left hand 49" propeller for light engines PPG, soaring trikes, motogliders. Can be 2-blade as well.
White propellers. Opposite side can be ordered black for better visibility through the prop (tractor planes). Different KOOL hubs, extensions etc.