Powered Parachute Flying Handbook

Chapter 7 — Takeoffs and Departure Climbs

Before Takeoff Check

The before takeoff check is the systematic procedure for making a final check of the engine, controls, systems, instruments, and avionics prior to flight. In addition, it gives the pilot an opportunity to establish a go or no-go decision. The engine temperatures should be rechecked, especially if any considerable amount of time has passed since the engine warm-up was completed, to make sure the engine and fluids are still within the manufacturers’ recommended minimums. If the air temperature is cold, the engine will cool down faster than when the air temperature is warmer; take a few minutes to bring the engine temperature back up to minimums. Recheck the wind direction. If the wind has changed, adjust your takeoff position so you remain into the wind. Double check the steering and suspension lines are not in the way of the forward movement of the tires and the steering lines are not tangled in the riser cables.

Start the Engine/Initial Rollout

Prime the engine, if so equipped, switch magnetos to the ON position, recheck that the throttle is not open beyond idle, and turn the electric master switch to the ON position. Visually check the area, shout “CLEAR PROP” and start the engine. Monitor the engine temperatures and check security of harnesses and helmets. Check that the strobe lights are ON, electric fuel pump is ON (if applicable), oil pressure is within limits (if applicable), and complete a final ignition system check.

Once again, the pilot has this opportunity to establish a go or no-go decision point. Check the intended runway and traffic pattern for existing traffic, and if radio equipped and a nontowered airport, announce field, type of aircraft, runway heading, and flight intentions; if a tower-controlled airport, contact ground or tower control to request a departure clearance. By adding thrust smoothly to about half to three-quarter throttle, the powered parachute will begin the takeoff roll.

Wing Inflation and Kiting

During the takeoff roll of an airplane, the goal is to build sufficient airflow over the wing to generate the lift required to lift the aircraft off the ground. Powered parachutes have two goals during the takeoff roll: to pressurize and raise the wing overhead making sure proper inflation exists for takeoff, and to create the airflow over the wing to generate the necessary lift. [Figure 7-3]

Make a final check to confirm that the cart is pointed in the right direction and nothing has moved into the way. Look over your shoulder to observe the canopy inflation. Advance the throttle smoothly and firmly to about one-half to two-thirds takeoff power. Too abrupt an application of power may cause the cart to yank the wing too roughly forward. This can damage the riser system and shorten wing life. This is more of a problem with higher horsepower engines than in lower powered aircraft. As the cart starts to roll forward, make sure both feet are on the steering bars to begin steering the parachute immediately.

As the wing starts to rise off the ground and climb, it is acting like a parachute with lots of drag; the cart does not move forward much. As soon as the wing passes through the 50° angle to the ground, the drag dramatically decreases as the parachute becomes a wing and the cart will begin to pick up forward speed very rapidly. You must reduce the engine thrust enough at this point to prevent the powered parachute from becoming airborne prematurely. If the initial thrust reduction is too great, the wing will begin to lose pressurization and settle back to the ground. If the thrust reduction is not adequate, the powered parachute will continue to accelerate and become airborne. On occasion the wing can become locked-out, or stuck in the prop wash; easing back on the throttle will allow the wing to settle out of the prop wash. Once again, easing the throttle smoothly forward will assist the wing in climbing through the prop wash and climb overhead above the fuselage.

As the wing is coming up in back of the cart, one side of the wing may inflate and rise faster than the other side. That higher side should be given a little bit of steering control to allow the other side of the wing to catch up. If you don’t make the correction early, the wing will want to fly over to the slower-inflating side. This may create wing oscillations, especially if combined with too slow a takeoff speed. While it is important to not over-control, remember that wing controls during kiting are sluggish and more control inputs are needed than during flight.

Now is the most critical point during takeoff and possibly during the entire flight. While the parachute is inflating and rising overhead, most of the powered parachute’s weight is still being carried by the wheels and the suspension system. The goal is to get the wing overhead and then transition the load from the wheels to the wing.

During the inflation and takeoff roll, you need to divide your attention between the direction the cart is going and the wing. When the wing is overhead, perform the “rolling preflight.” You need to quickly inspect the wing to make sure it is fully inflated and there are no line-overs, end cell closures, pressure knots, or huge oscillations before adding full power for takeoff. This all has to be done with quick glances.

Line-overs are very easy to detect because the wing will be obviously deformed and look like it is pinched by the line that is over the top of the wing. If you see a line-over, shut down and set up again.

End cells of the wing not inflating are something additional to watch for. Most powered parachute wings have large cross-venting in the cells to allow the entire wing to pressurize evenly. Generally, the wing will pressurize in the middle first. As the pressure evens out across the wing sometimes the end cells of the wing simply do not want to inflate. It is imperative that the pilot visually sees end cells inflate before taking off. Sometimes all you have to do is wait for the end cells to open. On some wing configurations it is recommended that the steering tubes be “pumped” lightly to help open the end cell openings.

Pressure knots are harder to determine during a rolling preflight. It may be very hard to see what is going on with the lines themselves, so the pilot may find it better to look for deformations on the bottom surface of the wing caused by one line being pulled more than it should be. Trying to take off with a pressure knot will result in the powered parachute turning very sharply to the side of the pressure knot. It will be nearly impossible to correct for that turn without nearly stalling the wing with the input on the other side. The engine will have to be kept at a very high setting just to maintain what little altitude is gained.

Wing oscillations occur for several reasons. There may not have been enough power added initially to kite the wing, or the pilot may have waited too long to correct for a wing that was flying to one side. Some light oscillation is okay, and will merely lift one side of the powered parachute into the air before the other. On the other hand large oscillations will actually change the lift from a straight upward vector to an upward and side-pulling force. An oscillating wing forced into takeoff will most likely roll the airframe, which is an undesirable cause and effect.

Oscillations are easier to prevent with good inflation techniques than they are to correct. However, if a wing is oscillating, it is possible to correct by steering the wing opposite to the side that the wing is drifting towards. In other words, manage the wing, steer it straight. The wrong inputs can make the problem worse. If the oscillations become too severe, it is best to abort the takeoff and set up again.

It is critical for the wing and lines to become verified, or fully inflated, directly overhead and centered, with the lines free of tangles. An acronym of LOC is often used to verify the wing is ready for takeoff: L – Lines Free, O – Cells Open, C – Wing Centered. Once the wing is fully pressurized, centered above the cart and the suspension and steering lines are free of tangles, slowly increase the throttle to takeoff thrust. The increased thrust accelerates the powered parachute forward until the airflow over the wing generates enough lift to get the PPC airborne. Continue to increase throttle gradually to the desired pitch attitude. Your feet have been resting on the steering bars throughout all the ground operations, and can be used to steer.

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