How An Airplane Propeller Works

Sir Isaac Newton’s third law of motion: If an object A exerts a force on object B, object B must exert a force of equal magnitude and opposite direction back on object A. This law is not always evident to the naked eye, but it is the crux of anything that moves us through the world. This “action and reaction” principle even applies to how an airplane propeller works. 

Your feet push against the ground propelling your body forward when you walk. Tires kick back against the road as the wheels on your car turn and move you down the road. But what about propeller-powered planes? These do, too!

A propeller is essentially a machine that moves you forward through the air as it turns, “lifting” you in the intended direction. Though it works much the same as a screw, it looks slightly different. Generally, a propeller has two, three, or four twisted blades (sometimes more) poking out at angles from a central hub spun around an engine or motor. The twists and angles are really important. A propeller is shaped like a wing, producing higher air pressure on one surface and lowering the air pressure on another surface.

We acknowledge that not everyone is as passionate about how propellers work as we are. And it’s okay if you’re not! If you are a private licensed pilot in California or Nevada, looking for “propeller repair near me,” contact Stockton Propeller.

How An Airplane Propeller Works

When the Wright brothers learned how to combine engine-powered propellers with the other parts of their flying machine design so they could go forward and upward simultaneously, the flight was born. Planes took to the skies!

The propellers’ inventors designed them to look somewhat like screws — and it’s easy to see why this basic design was their starting point. 

To “push” a screw into a wall, you apply a clockwise turning force to the screw with your screwdriver. The screw’s spiral groove (sometimes called a helical thread) converts the turning energy into a push that forces the screw into the wall and secures it there. 

Propellers are similar to screws, but they are not exactly twins. They are, of course, doing a completely different job. An airplane propeller’s purpose is to make more or less thrust (driving force) to varying points of a flight (during takeoff, during landing, or at a steady cruising speed). The propeller blade’s angle and its overall size and shape affect the thrust, and so too does the engine’s speed. 

Another difference is that while a screw moves into a simple, solid material and meets a (more or less) constant oppositional force, a propeller is moving in a fluid airstream, and there are all kinds of extra factors to consider. For example, although a propeller produces enough thrust to move you forward, it also has enough drag to hold you back and slow you down. 

Another difference between screws and propellers is that propellers have both twists AND angles. A screw has a constant pitch, while the slope of a propeller blade varies along its length. The rise is steepest at the hub (in the center) and shallowest at the tip. 

The propeller’s parts move at different speeds: the propeller blades’ tips move faster than the hub’s positions. The propeller blade’s angle should be greater near the hub, where the propeller is moving slowest. Then, shallower near the tips where the propeller is moving fastest. This reasoning is why propeller blades are slightly twisted. Without this twist, the propeller would be producing different amounts of thrust at the hub and the ends, which would put it under great stress.

How A Propeller Generates Thrust

Propellers generate thrust, but how exactly does that happen? 

A spinning propeller sets up an air pressure lower in front of the propeller and higher behind it. Downstream, the pressure eventually returns to normal conditions. As air passes through the propeller, the velocity is greater than the free stream because the propeller works on the airflow.

What About Acceleration?

For airplane acceleration, the thrust must be greater than the drag. By increasing both the engine power and the propeller revolutions (RPM), the air is increasingly accelerated across the propeller blades, creating a stronger pressure differential, pulling the airplane forward. This pressure differential accelerates the aircraft but limits the available thrust. As you accelerate, the drag load increases. Because of this, higher airspeeds require more power to accelerate.

A propeller’s efficiency also plays a large part in acceleration. At approximately the 80% efficiency point, any increase in forward airspeed results in a loss of propeller efficiency. This lack of efficiency at higher airspeeds also decreases the thrust and power available.

Propeller Diameter

A variable-diameter propeller would be most efficient in an ideal world, allowing for a large diameter for low airspeeds as well as a smaller diameter for high airspeeds. Due to structural, control, and weight issues, variable diameter propellers aren’t practical. Instead, the diameter of most propellers allows for a “happy medium” between varying airspeed operations.

Putting All Of This Together & Making It Work

Propellers convert engine horsepower into thrust by accelerating air and creating a low-pressure differential in front of the propeller. Since air naturally moves from high to low-pressure, you are pulled forward when your prop is spinning.

But if the propeller isn’t spinning correctly, isn’t precisely balanced, or needs other maintenance or repairs, you won’t be pulled forward. And this is where it gets dangerous!

We realize that everyone is not as passionate about how propellers work as we are. And it’s okay if you’re not! If you’re in Northern California or Nevada and you’re looking for “propeller repair near me,” contact Stockton Propeller.

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Top 5 Reasons Why You Should Be Flying

There are few experiences available to humans that offer the exhilaration of total freedom and limitless vistas while saving significant travel time. Getting your pilot license and flying a private aircraft accomplishes these feats and then some.

Training for your pilot license is more accessible than you might imagine. View the world from above with us as we detail several ways “regular” people can and should learn to fly.

Stockton Propeller is a full-service propeller overhaul and maintenance facility with the function and performance of your aircraft as the height of our service. Stockton Propeller can perform needed propeller inspections to help ensure your airplane is in good working order.

We perform static balancing in-house to keep your aircraft in top-flight shape. Visit our website today to learn more and enjoy your flight.

A Pilot License for Every Flyer’s Dream

Portrait of confident pilot standing with stewardess and private jet in background at terminal

Pilot licensure varies tremendously. Selecting the type of pilot license you want depends largely on your flight goals. You can choose to apply for a private pilot license all the way up to a commercial license. You may even want to become a flight instructor if you’ve dreamt of flying as a career. 

There are several pilot designations between private and commercial. You can specialize in recreational and sport pilot certificates depending upon your purpose in flying and budget. In the classroom setting, you will learn about aircraft propeller maintenance procedures

Dipping your toe in the flying world begins with a student license, for which you must apply. In addition to filling out the required paperwork and training eligibility with the FAA, you’ll also have to pass a medical exam. 

People in general good health typically can fly planes and other aircraft legally. However, if you have a chronic condition, you may want to check it against this FAA list to see if it may affect your pilot training eligibility.

If the FAA approves your pilot license application, it’s time to obtain a student pilot license.

Learn at Your Pace

Thankfully, the eligibility requirements for a student pilot license are pretty straightforward:

  • Be at least 16 years of age (14 if you’ll pilot a balloon or glider)
  • Have fluency speaking, writing, and reading in the English language (the Universal language of pilots and the flight industry)

Once you’ve applied for and obtained your student pilot license and your medical certificate, you can begin fight training.

Finding a local flight school in your area is pretty simple: Google “flight schools near me,” and you’ll get an array of options.

Join the Piloting Community

If you know another pilot, you might try to get a referral for a reputable school near you. Check on their comprehensive offerings, and be sure to compare costs between providers. This type of activity may not be the place to seek out the biggest discount, just saying. 

A happy professional woman pilot sitting at the airport.

Instead, look for experience, reliability, an excellent safety rating, and stellar reviews online or on social media. When learning to fly, you may want to gain more background on the pilot community. Try searching out and joining a few social media groups dedicated to flying and learning to fly in your area. 

When you join the piloting community, you’ll share unique skills and experiences in common with a dynamic and daring group of people all over the world.

Learn new skills at every age

Your training will include ground-based classes to learn the science and physics of flight, safety procedures, emergency protocols. And you can expect to learn the rules and regulations of the airspace during this time.

You’ll also log flight time with an instructor to learn how to operate a single-engine aircraft. To gain licensure, you must log 35 hours of flight time in varied conditions and aircraft. You’ll also take written exams, pass the FAA check ride, and be a licensed driver.

The beauty is you learn at your pace, depending on your flight school’s training schedule. A typical student can earn her PPL in about three months!

Gain Confidence, Learn More, Fly Bigger Planes

Learning to fly means plenty of advancement opportunities for the hobbyist and professional alike. Once you’ve achieved your PPL, you can choose to maintain that foundational licensure. Or, advance your skills, experience, or career in flying with the following certificates:

  • Commercial Pilot License: Obtain this certificate if you wish to earn money as a pilot. PPL holders cannot receive compensation for flying.
  • Airline Transport Pilot License: To fly for commercial airlines, this certificate is required of all pilots.
  • Commercial Multi-Engine Land: Think of this certificate as an add-on to your PPL or CPL. You’ll cover different equipment and emergencies and how to navigate them safely.
  • Certified Flight Instructor: This level of training allows you to teach new students pilots how to fly.

There are several more advanced certificates available that you can add to your credentials as you gain experience and knowledge. With changing technology and climate, flight education and safety procedures evolve over time. Pilots must stay on top of new industry developments as they arise.

Flying is Fun, Relaxing, and Can Save Time on Travel

Of course, flying is an endeavor to take up with safety, education, and experience in mind. However, there are over 600,000 licensed pilots in the United States alone! 

Further, when you fly, traffic is much less of an issue. True, you’ll have to be watchful and communicative on take-offs, landings, and near airports. But, for longer flights, private air travel may be as safe as driving on the road.

No Ownership Required

Though many pilots own an aircraft, it’s possible to rent an airplane to log your hours or fly for fun. Typical rental rates run about $125.00 per hour, depending on the type of aircraft. You’ll want to check rental policies to find out if fuel and other fees may cost extra.

Co-ownership is also an option for pilots who want to fly, but not own and maintain an aircraft by themselves.

Call Stockton Propeller to Keep Your Airplane Flying Happy and Safe

Stockton Propeller keeps your propeller blades balanced and in top shape for safe and reliable flying time, every time you take off (and land, for that matter.) To get a repair quote or view our current inventory, visit Stockton Propeller today.

We lead the industry in safety, functionality, and customer service for every aircraft and pilot we serve.