CYPRES Closing Loop
by Kai KoernerUsing the Cypres loop for closing the main container is not a good idea. The Cypres loop was designed for reserve use only. This loop allows a quick container opening after the loop has been cut. The small diameter (approx. 1.6 mm) reduces the pull force a lot, the use of silicone (all ready made loops provided from Airtec are siliconed on the first 2) reduces the pull force further down to 50% against a regular reserve loop. These features fit perfect for reserve containers where you have a high pressure for a long time on the ripcord pin. The tensile strength is around 180kp.
The loop material consist of polyethylene, all actions that might build up excessive heat by friction should be avoided, because the material will loose tensile strength at tempeatures above 100° C. This requires careful acting from the rigger. Reserve pull up's have to be extracted very slowly and only from below the ripcord pins.
Main container loops have a different task. Sometimes the container has to be closed very quick that not always happens very gently. The reduced tension on the closing pin with a Cypres loop may make a main container open earlier than expected.
Originally published in rec.skydiving
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