Pitch Control and Aborts During Launches

 

The safety of all launching methods is dependent on a stable and controlled wing overhead. In reverse launches, most troubles happen when the wing gets in front of the pilot and collapses during any of these stages. Reverse launches require some kiting ability, and pilots have a wide range of skills with regard to how well they can center the wing if it drifts to the side. All aspects of kiting are important, but pitch control and knowing when to abort are the most powerful skills that will help prevent launch accidents.

To simplify the process of launching, I have broken it down into 5 specific segments (Lift – Check – Stabilize – Turn – Launch). The following is a discussion of these phases of launch and common issues that become involved. For the more critical of these issues, the best practice is to know how and when to abort the launch. For other scenarios, awareness of pitching behavior and how to anticipate and manage this should be the priority during the launch phases.

Launch Sequence – 5 segments

  • Lift  Helping the wing ascend to a point overhead.

  • Check During or after the wing lift, use the brakes, C risers or D risers to stop the wing from surging upwind of overhead.

  • Stabilize Continuing to move backward and using power and the brakes, C or D riser to get the wing to a stable overhead position.

  • Turn The transition occurs when the pilot rotates from facing the wing to facing forward.

  • Launch/Torpedo Launch in a torpedo position.

Running forward under the glider. In a torpedo, the torso is bending forward to near 90 degrees or horizontal, the knees are bent with a low position, and the hands are back and up (this allows releasing the brakes up to trim and the ability to feel the wing. ).

BE ABORT READY – During the launch steps, prior to the Turn and Torpedo phases, an abort needs to be executed if anything starts to get out of control. To execute an abort, it must be something that you are ready to do once you begin lifting the wing. A good way to make this natural is to practice and learn different forms of aborting so that you can handle different situations that might arise.

The very powerful abort is the C or D riser pull (pull firmly, all the way to your belly button). This is one of the biggest benefits of launching with this style of lift, as the pilot has both of these risers already in hand. During A/C or A/D launches, you can also pull the brakes fully (behind your back while still facing the wing), but in high winds, there will be a much stronger burst of power as you first pull. This can sometimes convert to a force that pulls the pilot into the air or downwind quickly.

Below are some events and situations that happen somewhat frequently during launches. With each, there is some discussion to help pilots understand the factors and perspectives that can build their pitch management skills and awareness of when to execute an abort.

Events during the Lift, Check, and Stabilize phases of launch:

 Abort- When Wing is Not Centered

During the lift stage, an abort needs to be ready if the wing is not lifted close enough to the center for your skills to check and center. It is better to abort any time the wing is further to the side.   It can get messy trying to fix that and launch at the same time. After aborting, You can just restart, but without the extra issues and risk. Iit gets messy when done later, when the wing can get in front of the pilot. Launches where you try to do too much should be avoided. An abort is a form of enhanced safety, and pilots can increase their safety padding by practicing and learning how powerful aborts can be.

Abort when – Yanked into the Air

Another time to abort is when the check of the wing pulls you into the air while still reversed. Sure, some pilots have managed a launch when the yank happens. But, bad things can happen quickly. By limiting the tricky situations by using an abort, you will not get far from the ground and have an easy “do over”.

With A/C or A/D launches, if you abort quickly in this situation, you will not climb much higher into the air. If you decide to abort with the C or D risers, make sure you pull firmly and fully on the risers (all of the way to your belly button!) so that it fully kills the lift.

The kill from the brakes gathers much more of a bursting force before the wing runs out of energy. When doing so with the brakes as the check method (the standard or “straight-handed” method), the yank into the air has more potential to take you higher than you would want to stall the wing from. Timing is much more critical when using the brakes to check the wing.

With the brakes in hand, an alternative form of abort is to grab the C or D risers and kill the wing with a full and firm pull. If you do get lifted into the air further than a kill can be safely executed, flying the glider and not aborting might be the only choice.

Abort when – Wing overflies and collapses

If the wing has surged up and collapsed upwind of you, hopefully you are not in the air. If the result was that you fell down after the frontal, pull the brakes fully (or grab and pull C or D risers) and use this to keep the wing stalled and unable to come back overhead. If you were yanked into the air, likely after the collapse, you ended up on the ground anyway, so the same answer will usually suffice. Nasty stuff can happen when there is a partial or full collapse after you have been yanked into the air. There is no one answer for all of these scenarios, but this is a good time to make a huge point. Learning to over-check or abort a wing during launch is much better than letting the collapse happen.

Over-checked wing or wing checked too early

Regardless of which method of launch you use, sometimes the wing will be too far back after the check is released. This can happen when the wing is checked too hard or too long, or when you check the wing too early.

A common thing that pilots do at this point is to transition (turn) forward quickly and try to power the wing overhead. When power is applied to a paraglider that is aft of where it should be, the result will usually be a surge. This can lead to the wing jumping in front of the pilot and collapsing or needing a big check to keep it from collapsing.

A better way of dealing with the over-checked wing is to stay reversed while adding power to the hips. Whether you try re-lifting the A-risers or not, if the wing starts to come back overhead, it will often need a re-check. This continued motion backward and pitch management is the Stabilize phase. The key is to stay facing the wing after the check and to have awareness of what the wing is doing at this point. Is it all the way overhead? Is it about to surge? Is it overhead but still needs some checking  to keep it from flying ahead of the pilot? Learning to stay facing the wing for a step or two until it seems stable is one of the keys to better reverse launches.

A wing that is stable overhead will not do too much when the turn transition part of the launch happens. A wing that is surging or falling back will not launch well and can often be dangerous.

After the wing check, the brakes were released too quickly

When you need to do a harder check of the wing with the brakes, if you let the brakes up too quickly, the wing will surge. This can also happen with a C or D riser check, but is less common. So, learn to release your check device smoothly and manage the pitch by remaining facing the wing until the wing is stabilized (see below). Again, this is the Stabilize phase of launching that helps ensure that the wing is not moving forward or back and is overhead at a good angle for the turn to happen.

Stabilize pitching after the check:

The goal here is to make sure that the wing is not surging or in a situation where it might surge ahead of the pilot during or just after the turn. In a sense, this is simply a brief moment of kiting after the check where the pilot synchronizes with what the glider is doing. In some situations, this can be a split second. For example, the wing came up quickly in a light wind, and the pilot checked it hard with the C-risers. The wing stopped overhead perfectly, and it is not moving. The pilot will not have issues rotation forward with this, well handled, lift.

In some situations (mostly in light winds when the wing does not come up fast), it requires the pilot to continue moving backwards for a couple of steps prior to the turn. A common issue in light winds is that pilots stop as they check the wing. They then turn forward, and in a light wind, the wing normally pitches forward as a result of the motion of the pilot stopping, and often the wing gets in front and collapses. This is where backing up helps the wing stabilize during the turn transition.

If the wing has been checked and is slightly back behind the pilot. It is better to release the check (brakes or  C or D riser) while still facing the wing and back up but not turn until the wing is either back over head or has been checked again (if it surged upon the release).

Turning forward:

While turning from reverse to forward, keep your attention on the wing. Even if the wing surges during the turn, you can feel it from the risers and brakes. If during the turn, something goes wrong and your control diminishes, you can still abort! The abort begins to get much trickier once you become airborne or are running fast, so at this point the stability should continue to be solid.

Launching and torpedo:

Pitch control needs to continue during the run. In light and steady winds, you can have your hands at or near trim to allow the glider to have more speed and achieve the best L/D speed that will get the wing away from the ground. Keeping some brakes on during the run will help stabilize the wing on steeper launches or when there is more active air. Keep in mind that brakes pulled to around shoulder height help make the wing more resistant to collapse.

If you have the brakes pulled a bit more during the start of the run, avoid letting the brakes up quickly. This can cause the wing to surge in front of you. Instead, if you want to get closer to Best L/D (i.e., trim speed), make sure you let the brakes up smoothly as you accelerate.

The torpedo position helps with much of the above. In a good torpedo, the hands are free to keep a light touch that allows more feel for what the brakes are doing. It is hard to hold the brakes up near the pulleys when the pilot is upright and not in the “bent at the hips” position that is key to the torpedo launch.

The launch is not finished until the pilot is well away from the ground. Make sure this has been achieved before trying to get seated fully in your harness. The glider can be flown while the pilot remains in a torpedo or in an upright, running position, but the attention should be on the feel of the brakes and awareness of the glider’s pitching movements. Whatever technique you use, keep your legs down and at the ready to run should the glider come back down after leaving the ground.

Keep an abort at the ready and the pitching steady in your launches and you will be the one in control of your safety.