In the case of a collision, what is essential to do immediately after checking altitude?

After checking altitude in the event of a collision, establishing communication is essential. This step is vital because it allows you to connect with your fellow skydivers or any ground personnel who may be in a position to help. Open lines of communication help share information about the situation, assess the conditions of all parties involved, and decide on next steps. Timely communication can enhance safety and facilitate effective responses to the incident.

In the scenario of a collision, other actions might be necessary, but they would typically follow after communication has been established. While assessing injuries is important, it should not take precedence over ensuring that everyone involved is aware of the situation and can contribute to managing it. Deploying a reserve parachute is also critical in the case of a malfunction but is not applicable as an immediate reaction to a collision situation where altitude has just been monitored. Attempting to separate might seem logical, but without proper communication, this could lead to further complications or even additional collisions.