Main and Reserve Entanglements

A jumper should prepare for their 'personal-best' PLF on landing. The descent rate under entangled parachutes may be close to terminal velocity.

When sport parachuting used surplus military gear, it had canopy release systems (Capewells) that were never intended to be used in flight. Capewells were developed for the paratrooper scenario: one of low exit altitude and only enough time to deploy a reserve by hand if the main did not open. The release's intended use was on the ground, after the paratrooper landed.

As the surplus gear made its way into the sport, many adaptations to the release mechanism were made. The release system became slightly easier to use, but still required pulling the release on each riser separately.

The jumper community was split as to whether it was better to cutaway or not. Some believed that 'something was better than nothing'. Also the way the reserve was deployed was significantly different than today's sport rigs. Most reserves were chest mounted and may or may not have a pilot chute.

There was the occasional mis-match of procedures with the type of reserve. For the chest mounted reserve, no pilot chute was installed if the procedure called for 'not cutting away'. A reserve pilot chute was installed if the procedures called for cutting away first.

From 1969 to 1973, eleven of 193 US fatalities were because of a main and reserve entanglement. Circa 1974 was the time when cutaways from any type of unlandable partial malfunction was beginning to be strongly encouraged.

The 3-ring release mechanism was introduced in 1976 and realized wide spread use very quickly. This allowed jumpers to cutaway both risers by pulling on one handle. Altitude loss was minimal and a reserve could be deployed into clear air.

Main and reserve entanglements continued to occur because of improper emergency procedures and lack of altitude awareness by AAD equipped jumpers.

Some jumpers would pull the reserve and then cutaway or not cutaway at all when faced with a partial malfunction.

Some jumpers would have both parachutes deploy simultaneously if they pull their main within the activation altitude of their AAD.

1981: There were 3 main-reserve entanglement US fatalities in 1981. Two of the jumpers, with 313 and 29 jumps respectively, did not cutaway a malfunctioned main before pulling the reserve. The reserve and main pilot chute entangled, preventing the reserve from opening. The third jumper with 3 jumps had a suspension line catch on the container, so the main could not separate.

A very recent main-reserve entanglement fatality in 2001, was because a jumper held a freefly tube in his left hand during main deployment. The main and tube entangled. Instead of dropping the tube and cutting away the main, this jumper tried to clear the tube from the main. At the activation altitude of his AAD, the reserve opened. That too entangled in the mess above him.

Another 2001 main-reserve fatality was because the main first entangled with the jumper's camera equipment and would not clear the jumper even after a cutaway. The reserve entangled with the main.

Another 2001 main-reserve entanglement was because a jumper did not cutaway before deploying the reserve. This Scottish jumper sustained severe injuries.

A rather unusual way for simultanoeus deployment happened to an AFF student in 2000 at a Southern California DZ. He rolled as he deployed his main. The left main riser apparently pulled hard enough on the reserve static line (RSL) to open the reserve. He cutaway the main and it entangled with the still deploying reserve.

Main-reserve entanglements also happen when a jumper has a pilot chute in tow, pulls the reserve and then the main deploys at the same time as the reserve. Entanglements have occured whether or not the jumper cut the main away first. This is one reason why the jumper community is split about whether or not to cutaway from a pilot chute in tow.