paramotor lessons theory of flight learn to fly

Paramotor Theory Of Flight & The Basics Of Paramotoring

Before you can get to the fun part of taking to the sky, you will need to understand some basic theory of flight. You should also understand the basics of paramotor wing design, and how they work. The better your understanding, the better you will do when it comes time for your practical paramotor lessons.

This post just covers the basics, more in depth theory of flight, and lots more important beginner to intermediate paramotor pilot information can be found in our paramotor pilot’s book of knowledge by clicking here.

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The theory of flight for paramotors

As you can see in the picture below, there are certain forces acting on a paramotor wing.

WEIGHT & LIFT

The wing must produce enough lift to overcome the weight of the paramotor. This weight is constantly being pulled down by gravity, and lift is the opposing force generated as the wing moves forward, or as air moves over the wing.

THRUST & DRAG

Thrust is generated by your legs as you run forwards to launch the wing. Obviously, there’s only a certain amount of force a human can produce, so to achieve flight, a small engine is required to turn a propeller to push you into the air.

Paramotors will produce an average of 60 kilograms of thrust, but here’s always an opposing force that’s doing it’s best to slow you down, and pull you back the other way, this is known as drag.

paramotor lessons theory of flight forces

LIFT

Lift is generated by the flow of air over the paramotor wing. The shape of an airfoil causes air to flow faster over the top surface than it does past the bottom surface. The faster flowing air decreases the surrounding air pressure. Because the air pressure is greater below the airfoil than above, a resulting lift force is created. This can be explained by bernoulli’s principle.

To generate more lift, the angle of attack can be changed to push, or deflect air downwards. This is in accordance with newton’s third law of motion. But if the angle of attack keeps increasing, the wing will eventually stall, this point is known as the critical angle of attack, and is somewhere around 15 degrees for all wings, and all aircraft.

paramotor lessons bernoulli's principle
paramotor lessons wing angle of attack

THRUST

The required thrust is generated by the spinning propeller. The speed at which the propeller spins is controlled by a hand held throttle. Once the pilot is airborne, airspeed always remains constant depending on the trimmer position (trimmers can be opened to give a slightly higher top speed).

By increasing throttle, more thrust is generated, giving you more lift. And decreasing throttle will have the opposite effect, decreasing the amount of lift generated, this is how we descend.

DRAG

Paramotors aren’t the most aerodynamic aircraft, and they produce a lot of drag. This high amount of drag means that top speeds are pretty low, with an average cruising speed of a beginner wing being around the 50 kilometer per hour mark.

As previously mentioned, trimmers can be used to increase the speed, and also the stability of a paramotor wing, we’ll look at trimmers later.

PITCH AND ROLL

Pitch and roll movements happen with brake and throttle input, and as the paramotor moves through turbulent air.

Pitch is the movement of the wing forward or backwards, this happens as you increase power to climb, or decrease power to descend. Roll are side to side movements, these movements happen as brake is pulled, and generally makes the wing bank and turn.

Paramotors are quite sensitive to turbulence, so you may experience pitch and roll as the paramotor moves through lumpy air. This will usually correct itself on stable beginner wings without the need for any pilot input.

Another common roll movement is known as penduluming. This is something you’ll experience on most flights after making turns. Turbulence will also trigger penduluming, and these movements are usually nothing to be concerned about while flying stable beginner wings. Penduluming can be corrected with very light brake input, or left alone will often correct itself..

paramotor pitch and roll eBook

Paramotor wing design

Paramotor wings are very loosely based on ram-air parachutes. They use the same basic design, but they are much more efficient. A typical ram-air parachute will have a glide ratio of around 5:1, but a modern paramotor wing will be around 9:1. This means you can fly nine feet forward, without using power, and you will only lose one foot in altitude.

A paramotor wing uses two layers of fabric, top and bottom, connected by fabric ribs that form multiple cells. These cells face forward on the leading edge, allowing air to pass through into the wing. As the wing moves forward these cells fill with high pressure air that inflates the wing. This forward motion keeps the wing inflated, and allows it to form the necessary aerofoil shape.

When a paramotor wing inflates, it forms a basic aerofoil that will create the lift needed to get you airborne. Lift will be created as you run, and as the thrust of the engine pushes you forward. The faster you run, the more lift the wing will produce, this continues until you reach the required speed to lift you into the air.

To get off the ground, you will need to overcome the drag holding the wing back, and the weight holding it down. If the take off speed of a wing is 10 MPH, you will have to keep running until you reach 10 MPH in order to leave the ground. If you’re running into a 5 MPH wind, you will only have to run at 5 MPH to get airborne.

Modern reflex wings will have a trim system, that can be adjusted to give slower takeoff speeds, and faster in-flight speeds. The trim system allows pilots to adjust the lift point, centre of pressure, and angle of attack of the wing, by changing the profile of the aerofoil. This is achieved by changing the length of the D and C risers, with a simple buckle release.

Trim systems have improved the safety of paramotor wings immensely. By activating the trim system, you will be moving the centre of pressure further forward. You will also be flying faster which creates higher pressure inside the wing. This lowers the risk of a dangerous type of wing collapse known as a front tuck.

When it comes time for your practical paramotor lessons, ask your instructor to demonstrate using the trimmers. Practice releasing them, and returning them to landing position on the ground before using them in flight.

The brakes can also be used to achieve slower take-off speeds, but you must be very careful not to stall the wing. By pulling down on the brakes just before take-off, a pilot can increase lift, similar to how flaps work on fixed wing aircraft, this will assist the take-off.

The brakes must then be gently released as soon as the pilot leaves the ground to avoid a stall. This must be done very gently and progressively, a sudden release of the brakes may cause a loss of altitude, or the wing may dive if it hasn’t reached the required speed to maintain level flight.

Risers and lines

The risers are used to connect the wing to the paramotor, and are made from strong and durable nylon webbing. Strong carabiners are used to easily clip the wing in before each flight, these stay attached to the paramotor.

You will usually find four or five points which connect to the lines. Looking at the picture below you can see the A, B, C, and D risers / lines. These lines connect to the wing, A’s are closest to the front, and D’s are at the rear.

You’ll also find the brake lines, which pass through pulleys on the D risers, and are held in place by magnets. These lines connect to the trailing edge of the wing to allow turning and flaring. As you pull the brakes, the rear of the wing will be pulled down, slowing that side and making the wing change direction.

The lines are very strong, and are made from tough materials called Kevlar and Dyneema. It’s possible for lines to snag on rough surfaces, or to catch on sharp prickly plants during take-off, so regular inspections should be carried out to check for possible damage.

paramotor lessons risers and lines

I hope you’ve enjoyed your first lesson on paramotor theory of flight, and the basics of paramotor wings. Go back and read this article again until it’s all crystal clear in your head. Remember, the better your understanding of the theory of flight, the better your first flight will go.

Test your paramotoring knowledge by taking the paramotor pilot exam HERE

When you’re ready to take things further you’ll need to arrange some training. You can read all about my training experience way back in 2013 so you know what to expect > HERE.

Find out if you can teach yourself to paramotor here

And find out all of the equipment that you’ll need to get before you can start flying > HERE < and all of the essentials for your kit bag > HERE.

Find out whether paramotoring is as safe as everybody’s telling you here

Still wondering what the difference is between paramotoring and paragliding? THIS POST will explain everything.

Learn how to forward and reverse launch your paramotor here

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