BASE Jumping Malfunctions

Misrigging at Bridge Day 2006 - Jumper incorrectly assembled his reverse riser system as shown. This error, if not noticed by our gear checkers, could have been fatal. The correct method is for the white loop to first pass under the small ring and THEN through the first grommet. Finally, the white loop passes through the second grommet where the yellow teflon cable holds it in place.

Missing Pilot Chute at Bridge Day 2007 - An experienced BASE jumper's pilot chute became disconnected from the bridle immediately after parachute deployment. The jumper landed safely while the pilot chute floated into the top of a 60' tall tree. This document provides full details of the incident, as well as instructions for proper pilot chute installation on a bridle.

Line Overs

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This malfunction occurs when one or both control (brake) lines wrap over the top of the canopy, often causing the canopy to spin and descend rapidly. It can also occur with lines other than control lines.

Cause: Sloppy packing techniques.
Prevention: Perform a line check before packing and directly prior to "cocooning" the canopy. All line groups should be stacked down the center of your canopy, one group on top of the next, in an orderly fashion.

Cause: Failure to use a Tail-gate (on slider-down/removed jumps only!).
Prevention: If jumping slider down/removed, have a BASE gear manufacturer install a Tail-gate. The Tail-gate is a reefing device which promotes nose-first inflations, virtually eliminating the possibility of a line-over on slider-down/removed jumps. As a side-note, NEVER use a tailgate on a slider-up jump for two reasons: 1) the control lines are one of the primary forces that drive a slider down the lines during the opening sequence -- with the control lines reefed shut by the Tail-gate, you may experience a very slow opening if you attempt to use a Tail-gate while jumping slider-up. 2) it is quite possible that the Tail-gate could snag on the slider during the deployment sequence giving you a slider hang-up (very, very bad). Be sure and consult with a BASE gear manufacturer on the proper use of Tail-gate. For slider-down/removed jumping, use of a Tail-gate has become THE standard. Used properly, it virtually eliminates the line-over malfunction.

Cause: Failure to stow brakes.
Prevention: Insure that your brakes are stowed for each jump. By failing to stow the brakes, the control line length is increased allowing them to possibly slip around or over the top of the canopy.

Cause: Routing brake lines outside of the slider on slider up jumps.
Prevention: On all slider up jumps, make sure that the brake lines run through the slider grommets and toggle keepers. Otherwise, the brake lines are free to wrap over top of the canopy while the slider continues to constrict the canopy from opening. In addition, the brake lines cannot help the slider come down, which may cause slider hang-ups.

If you experience a slider up line over, try to pump the brakes and clear the line over. In many cases, line overs clear themselves. Otherwise, using and releasing one of the new line release toggles (i.e. WLO or SuPeR toggles) is another option that will clear the line over. You can also cut the affected brake line with a hook knife. If you have to release or cut a toggle, do not release the 2nd toggle. With one lost toggle, your canopy will only lose stability in 1/2 of the tail, while the loss of both toggles will make the entire tail of the canopy unstable. Without a toggle, the jumper must use the corresponding rear riser to steer and flare. Flare at 50% normal stroke so you won't collapse the canopy and do a PLF. Try to land in the water, if available.

If you experience a line over while using the brake line mod (slider down or off), start by pumping the brakes to try to clear it. If unsuccessful, just release the toggle, which will clear the line over. If you have to release a toggle, do not release the 2nd toggle. With one lost toggle, your canopy will only lose stability in 1/2 of the tail, while the loss of both toggles will make the entire tail of the canopy unstable. Without a toggle, the jumper must use the corresponding rear riser to steer and flare. Flare at 50% normal stroke so you won't collapse the canopy and do a PLF. Try to land in the water, if available.

Dropped Brake Lines

This malfunction involves the accidental release of toggles while using the brake line mod, often occurring while unstowing the toggles from the risers. Toggles are not retrievable after released when using the brake line mod, therefore secondary steering and flaring methods are required.

Cause: Inadvertent manual release of a toggle while using the brake line mod.
Prevention: Don't drop your toggles!

If you have to release or cut one toggle, do not release the 2nd toggle. With one lost toggle, your canopy will only lose stability in 1/2 of the tail, while dropping both toggles will make the entire tail of the canopy unstable. Try to steer and flare using the riser to compensate for the missing toggle. Flare at 50% normal stroke so you won't collapse the canopy and do a PLF. Try to land in the water, if available.

Broken Brake Lines On Opening

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Loss of both brake lines during canopy opening can result if the toggles are improperly stowed or if the jumper used inadequate skydiving toggles with the brake line mod. On opening, the excessive forces presented on normal skydiving toggles are often too much to prevent them from blowing off, rendering them unretrievable.

Cause: Using standard skydiving toggles with the brake line mod.
Prevention: Do not route your brake lines outside of the toggle keepers on slider down/off jumps when using standard skydiving toggles, as this type of toggle will not always stay stowed during openings. This malfunction is virtually nonexistent with BASE specific toggles that are designed to stay stowed during the canopy opening process.

Cause: Improper stowing of BASE specific toggles
Prevention: Consult the owner's manual for the toggle/riser system that is being used, or ask an experienced BASE jumper for the proper method of stowing them.

If you lose only one brake line, maintain what toggles you have. With one missing toggle, your canopy will only lose stability in 1/2 of the tail, while the loss of both toggles will make the entire tail of the canopy unstable. Without a toggle, the jumper must use the corresponding rear riser to steer and flare. Flare at 50% normal stroke so you won't collapse the canopy and do a PLF. Try to land in the water, if available.

Line Twists

Line twists occur most often with skydiving rigs due to their high aspect ratios and can render canopies unsteerable and unlandable. Many Bridge Day injuries have occurred to jumpers who were unable to clear line twists, landing in the rocks or trees.

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Cause: Bad body position on opening, often head down.
Prevention: Practice BASE exits into a swimming pool or on a pendulator until comfortable. Jumpers can also insure that their eyes remain fixed on the horizon while exiting.

Cause: The most common cause is packing a skydiving canopy in a bag, which can tumble when pulled out of the container at low airspeeds.
Prevention #1: Freepack the skydiving canopy in the container if a tailpocket has been sewn into the tail of the canopy.
Prevention #2: Use a BASE specific container in order to reduce the chances of line twists. Regardless, line twists can be cleared by kicking your legs and pulling the risers apart.

Maintain a flat or slightly head high position during deployment to reduce the chance of your canopy or canopy bag snagging on the container and spinning during deployment. Regardless, line twists can be cleared by kicking your legs and pulling the risers apart. Don't give up! If unable to clear the line twists, jumpers can "climb" up the lines and pull on the rear line groups to attempt to steer the canopy from danger. High-performance canopies and canopies with higher aspect ratios (9-cells) are much more likely to have line twists than 7-cell or BASE specific canopies.

Pilot Chute (PC) In Tow

This malfunction occurs when a PC fails to inflate and properly pull the canopy from the container. Failure of the PC to inflate will surely result in death.

Cause: PC is not large enough or does not produce enough drag for the length of freefall delay.
Prevention: Use the following size PC's: 0-2 second delay = 46" ZP, 2-4 second delay = 42" ZP, 4-7 second delay = 38" ZP, 7-terminal = 32" ZP.

Cause: Bridle is too short and/or PC is trapped in the jumper's burble.
Prevention: Increase bridle length to industry standard 9' long.

The solution is to roll on your side slightly to allow the PC to catch more air and inflate properly. Manually grabbing and tossing the PC is also a last ditch effort. In very rare cases, jumpers have been known to reach back and grab their shrivel flaps, pulling the canopy out of the container and off to the side.

PC Trapped in Lines

This malfunction occurs when the pilot chute is trapped in the lines of the canopy, causing excess drag on one side.

Cause: 9' bridles are the likely culprit, allowing pilot chutes to reach the brake lines in most cases. While a rare malfunction, it can be easily dealt with if recognized.
Prevention: If this malfunction occurs more than once on the same parachute, try using a different (longer) brake setting as your canopy may be near collapse with no forward speed shortly after opening, thereby facilitating this type of malfunction.

If you do experience this malfunction, the solution is to use opposite side toggle pressure to allow the canopy to fly straight. Be careful when flaring, as the canopy may still want to turn (1/2 to 3/4 flare is advised). The author of this document actually experienced this malfunction.

PC Over Front of Canopy

This malfunction occurs when the pilot chute gets wrapped over the front of the canopy, causing excess drag.

Cause: 9' bridles are the likely culprit, allowing pilot chutes to reach the front of the canopy. While a rare malfunction, it can be easily dealt with if recognized.
Prevention: If this malfunction occurs more than once on the same parachute, try using a different (longer) brake setting as your canopy may be near collapse with no forward speed during opening, thereby facilitating this type of malfunction.

If you do experience this malfunction, the solution is to fly the canopy in 1/4 brakes in order to prevent the PC from inflating and producing too much drag.

Bridle or PC Wrapped Around Arm/Leg

As the jumper pitches or releases his PC, the PC or bridle becomes wrapped around his arm or leg. Failure to remove the bridle or PC from this position will result in death.

Cause: Bad body position is often the main culprit.
Prevention: Make sure that you are flat and stable during pull time.

Cause: Incorrect pitching of the PC from a BOC, usually toward the front of your body.
Prevention: Make sure you always pitch your PC away from your body to the side, and not toward your head or legs where it can wrap around your appendages. Hand-held PCs are more prone to this malfunction because a large portion of the bridle is exposed to the wind during freefall, however this method is safer because the jumper doesn't have to hunt for the PC handle.

If you are head down, the PC or bridle may wrap around your foot or leg, in which you should kick your legs to allow for the air to remove it. Never wear shoes with hooks on them, or simply put duct tape over them so they won't snag anything. If the bridle is wrapped around your arm, wave your arm and point it to the sky to remove it.

Overrotation

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This error occurs often with inexperienced jumpers by exiting in a bungee-jump diving style position (head down).

Cause: Failure to leave the object in a head-high position, causing over rotation of the body.
Prevention: Practice BASE exits into a swimming pool or on a pendulator (available within our Bridge Day jump courses) until comfortable. Jumpers can also insure that their eyes remain fixed on the horizon while exiting. Jumpers who fixate on the ground will often overrotate, which can lead to line twists, bridle or PC entanglements, and other malfunctions that can cause serious injuries or death.

If you do find yourself in a serious head-down position, depending on the height of the object, you may chose to wait one additional second to try to come back to a belly-to-earth position. Keep in mind that it's always better to deploy in a bad body position than to deploy too late, so use your own best judgment on this one.

BASE Jumping Malfunctions

Line Overs

Dropped Brake Lines

Broken Brake Lines On Opening

Line Twists

Pilot Chute (PC) In Tow

PC Trapped in Lines

PC Over Front of Canopy

Bridle or PC Wrapped Around Arm/Leg

Overrotation

Other Malfunctions or Potential Problems