North America:1 (800) 942-7767 International:+1 (937) 778-4200

Yellow, white, and purple RV-7 kitplane

Choosing a Prop for Your Project Plane: 3 Important Factors to Consider

Date: October 25, 2018 Category: Blog Tags: , , , , , ,
Print Friendly, PDF & Email

As any homebuilder will tell you, constructing an airplane comes with its share of uncertainties. However, part of the challenge and fun of building an aircraft is navigating these uncertainties and customizing the aircraft to your liking. One of the most critical decisions to make when building a kitplane is selecting the propeller to be installed.

When choosing a propeller for your homebuilt aircraft, you’ll need to take a number of factors into account, including the manufacturer recommendations, engine type, weight, noise, durability, RPM range, ground clearance, cost, and your performance goals for the aircraft. Choosing the right propeller is essential, as the improper application or modification of a propeller may lead to damage or serious accidents. To help you make a safe propeller choice for your kitplane, consider the following:

Engine/propeller combination

When it comes to selecting a propeller for a kitplane, a good place to start is with the powerplant type. Most of the popular kit manufacturers have carefully tested and researched engine/propeller combinations that they recommend to their builders. You might even be able to purchase a new propeller directly from the kit manufacturer, which will take much of the guesswork out of your propeller installation.

Safe ground clearance

Not every propeller that fits your selected engine will suit your aircraft in terms of ground clearance. A prop strike against the ground can cause expensive, often irreparable damage to the propeller blades or engine. It’s a good rule of thumb to leave a minimum of 7 inches between the prop tip and the ground to minimize the risk of a prop strike on landings. For tri-gear aircraft, a minimum of 9 inches of ground clearance is recommended for safe operation. Take safe ground clearance into account when choosing the diameter of the propeller for your homebuilt.

Buying a used propeller – is it worth the risk?

Purchasing used parts and materials is one way to make your homebuilt project more affordable. If you come across a damaged propeller you want to use, take caution. If the blades are bent, don’t try to straighten them yourself. Even if the prop appears to be in good condition, it may have internal damage that is beyond repair limits. Don’t take any chances: take the used propeller to an approved prop shop for an overhaul to have it assessed by a professional. During overhaul, the propeller will be disassembled and carefully examined to identify and address any damage or corrosion.

Building and flying your own aircraft is one of the most challenging and rewarding things you can do. Be sure you take time to research and select the appropriate aircraft propeller for your kitplane to enhance the long-term performance, safety, and dependability of your aircraft.

At Hartzell Propeller, we work with the world’s most popular kit manufacturers to develop suitable propellers to be installed with their recommended engine for the kit. If you’re building from one of these kits, you may be able to buy a new Hartzell propeller directly from the kit manufacturer. See our frequently-asked kitplane questions, and contact our technical team for more information about finding the right Hartzell prop for your homebuilt project.

Hartzell Propeller