In 1990 I built a two pin BASE rig. Effectively a pin closed Perigee (classic). It was, and is, in use as a pilot emergency rig. Not legal I know, but that was a different era. In early 1997 we built a one pin BASE rig. Totally different in appearance and function. The thinking at the time was that skydiving had gone from two (or more) pins to one pin so it must be better - less loops, grommets etc. What we found with this rig was in fact a number of undesirable traits that could all be addressed by introducing a second pin.

Also, we examined why single pin reserve containers were more popular in skydiving. It was related largely to the fact that 2-pin designs used steel cables with multiple pins. This forced both pins to move simultaneously. We were able to avoid this with the use of a flexible webbing bridle. Additionally, as skydiving rigs got smaller and smaller the extra closing surface and security wasn't required because the whole package was the size of small book. Conversely, a BASE rig holding just one parachute is bigger than many conventional skydiving rigs and could benefit from the greater closing area.

A single pin rig was by default "fatter" something that I personally don't believe is appropriate in a single parachute container mostly because I did a lot of tower jumping and had to deal w/ confined spaces. It also had a very wide variance in pin tension when it was placed on the body. This was a result of all the additional tension being focused on a single point.

Moderate pin tension on the ground could become dangerously high in the air.

More importantly, a single pin means a single grommet and when the full length of a long flap narrows to that grommet and/or it's reinforcing plastic you have a scenario that is ripe for catching (and holding) a line. This has killed many a skydiver back in the early 80's when free stowing was "cool". Interestingly, this month's Parachutist magazine has revisited this scenario in an article that addresses the recent grommet related incidents in skydiving.

Basically, I didn't like the rig and it never saw production.

Ultimately, I designed a rig from the ground up to use two pins. There are no shared parts (except leg pads) between the first Perigee Pro (1997) and the earlier Velcro closed perigees.

What we gained by going to 2-pins: more consistent pin tensions, lower overall pin tension, reduced line entanglement potential, a flatter profile and safer use if people (against recommendation) jump hand held. Safer because if a pin is accidentally pulled the rig will remain closed.
The Perigee Pro has a lot of features beyond what I mentioned above that I believe really enhance it's function and safety but this isn't the forum for that.

Suffice it to say, since it's introduction, the Perigee Pro has been copied by one European mfg and the two pin approach has also been adopted by two US manufacturers.

Adam Filippino
Consolidated Rigging, Inc.
http://www.crmojo.com

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