|Date||Location||Category||Age||# Jumps||AAD?/RSL?||Dropzone.com Report||Dropzone.com Discussion|
|26/05/2008||Skydive Arizona, AZ||CCOL||49||2250||Y/||336||#3221640|
|DropZone.com Description: During a large formation load the jumper was making a straight in approach and overtook another jumper in front of him. The jumpers canopy partially collapsed and he hit the ground with a semi inflated canopy.|
|USPA Description: Following an uneventful multi-aircraft freefall skydive and initial canopy descent, this jumper flew his parachute directly above and behind another skydiver's canopy at approximately 40 feet above the ground. This jumper's canopy collapsed, and he struck the ground hard under his partially inflated main, suffering multiple broken bones and internal injuries. He received immediate medical attention and was airlifted to a local hospital, where he died of his injuries several hours later.|
This jumper was taking part in a large formation skydive with approximately 60 other skydivers. Large formations often require each jumper to fly in heavy canopy traffic in an orderly pattern for landing. On his final approach, this jumper's canopy apparently hit the wake turbulence of the canopy in front of him and immediately collapsed.
Jumpers need to be aware of turbulence hazards to parachutes, which can come from many different sources. Each canopy creates a wake vortex capable of collapsing any parachute behind it; the turbulent air is found directly behind and above the canopy as it flies through the air. Additionally, wind passing over obstacles such as trees and buildings is disrupted, causing turbulence that can be found on and near the ground directly downwind of the obstructions. Skydiver's Information Manual Section 4 explains the effects of turbulence on canopies in Category C of the Integrated Student Program and cautions jumpers to anticipate turbulence 10 to 20 times the height of an obstacle on the downwind side. If possible, this jumper should have avoided the wake turbulence of the canopy in front of him by flying to the side of the canopy, rather than directly behind it.