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Safety Check | Spinning Line Twists

By Jim Crouch

Safety Check | April 2019
Monday, April 1, 2019

The Rolling Stones sang a popular song titled “Time is on My Side.” Obviously, Mick Jagger never had a high-speed malfunction. After receiving a letter from a concerned skydiver who witnessed an incident resulting from a low cutaway, the Safety and Training Committee discussed the hazards of one high-speed malfunction—spinning line twists—during the February 1-3 USPA Board meeting in Dallas, Texas. Following the discussion, the board added the following to Skydiver’s Information Manual Section 5-1.E: “Spinning main parachute malfunctions can lose altitude significantly faster and require a rapid response.  Checking your altitude more frequently is required to ensure cutting away the main parachute and deploying the reserve is done above your decision altitude.”

Over the last 20 years, at least 24 jumpers have died after failing to handle spinning line twists properly. There are several possible explanations for why so many have fallen prey to this tricky and deceptive malfunction.

  • From the first jump, a skydiver learns that line twists are just a nuisance that they must fix in order to steer the parachute. Although this is usually true for large, docile student canopies, it is not true if the parachute is not flying level and is spinning.
  • A quick look through YouTube videos shows skydivers spending anywhere from six to 30 seconds trying to untwist risers and suspension lines before pulling their cutaway handles to release their main parachutes, all while their parachutes spin rapidly toward the ground. The jumpers who are not using reserve static lines or main-assisted-reserve-deployment devices lose additional time and altitude falling away from their jettisoned mains before pulling their reserve ripcords.
  • During a spinning malfunction, jumpers can lose as much as 300 feet of altitude per revolution. It does not take long to end up dangerously low for a cutaway and reserve deployment.
  • Unforeseen issues add complexity to emergency procedures. Some jumpers have reported an inability to sheer the Velcro and pull the cutaway handle because it was sandwiched tightly between the harness and torso due to tension on the main lift web.
  • During a spin, centrifugal forces cause a jumper’s blood to move toward the feet and away from the brain, which can affect judgment and slow reaction times. In one case, a jumper spinning under a very small experimental main parachute lost consciousness and struck the ground in a hard, diving spin.

Skydivers need to start treating spinning line twists as high-speed malfunctions that require immediate cutaway and reserve deployment. Usually caused by a brake release or uneven risers trapping suspension lines, the situations are almost never recoverable, and trying to kick out of the twists is just wasting time and altitude.

Fortunately, there’s a lot you can do to respond to spinning line twists correctly. As soon as you find yourself orbiting around your spinning main parachute, immediately pull the cutaway handle and deploy the reserve. A faster reaction maximizes the altitude remaining for a reserve deployment and makes it easier to extract the cutaway handle from the main lift web, because the harness is not yet highly loaded. Sooner is better. Additionally, use an RSL or MARD. Many fatalities occur after the jumper releases the main parachute at a sufficient altitude but fails to pull the reserve in time. An immediate reserve deployment via an RSL or MARD can mean the difference between life and death.

You can prevent spinning line twists by jumping larger canopies at lighter wing loadings, packing carefully, stowing your brakes securely and deploying in a stable body position with your shoulders level with the horizon. Practice your emergency procedures in a training harness on a regular basis to help ensure you handle malfunctions correctly when the time comes. Don’t spend too much time trying to fix an unfixable malfunction. Pull your cutaway handle. And pull it immediately. Mick Jagger had time on his side. You don’t.

Jim Crouch | D-16979
USPA Coach Examiner and Tandem Instructor Examiner; AFF, IAD and Static-Line Instructor; PRO

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1 comments on article "Safety Check | Spinning Line Twists"

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Andres

4/22/2019 8:19 PM

Good article, I just don't agree with using a Skyhook or MARD after a spining malfunction specially if you also fly a small reserve, I had a double mal because of a Skyhook, the reserve came with assimetrical line twist and was spinning and diving rapidly towards the ground, O was lucky I had a lot of experience saving other spining malfunctions and was able to grab the rears of the reserve and pull one of them to make it fly leven and then kick out if it, I was doing and aff and my student pull at the correct altitude and I pull at 4500 ft, start my emergency procedures at 3500 after realizing I was no going to be able to came out of it, I fought with the reserve and came out of the twist at 600 Feet !!! Although I still have my RSL Skyhook connected if i had a spining malfunction I first disconnect it and follow my normal procedure this obviously required some extra time hence I try to always open above 4000 Feet whenever I fly a crossbrace canopy !! Good day to you all and safe skydives !!

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