Final answer:
Skydivers use automatic activation devices (AADs) like the CYPRES or Vigil for pre-meditated parachute jumps. These devices are part of the safety equipment that automatically deploys the reserve parachute under certain conditions.
Step-by-step explanation:
The question regarding which back automatic parachute model is used for pre-meditated jumps pertains to the safety equipment used in skydiving. While the question does not specify a particular model of parachute, it is important to note that for pre-meditated jumps, often skydivers use an automatic activation device (ADD) such as the CYPRES or the Vigil, which can automatically deploy the reserve parachute if the skydiver fails to do so manually.
In skydiving, the use of reliable equipment is paramount for safety, and thus equipment such as the ADD is commonly used in conjunction with a main parachute system. The main parachute and ADD are typically chosen based on various factors, including the skydiver's weight, experience level, and the specific type of jump being performed, to ensure a controlled descent and a safe landing.
Therefore, while there is no singular model that is universally used for all pre-meditated jumps, it's clear that the choice of back automatic parachute is crucial in providing a layer of safety, allowing for peace of mind during these precisely planned and executed skydives.