In the event of lost communications while flying IFR, what is the first action a pilot must take?

When a pilot experiences lost communications (often referred to as "lost comms") while flying under Instrument Flight Rules (IFR), the first action is to continue on the route that was assigned by Air Traffic Control (ATC) before the loss of communication occurred. This is a critical step because it ensures that the pilot remains on the intended path for safety and collision avoidance, as ATC has instructed the pilot based on traffic, weather, and other operational considerations.

Following the assigned route helps in predictable navigation, which is essential for maintaining safety in crowded airspace. It also demonstrates compliance with established aviation protocols, minimizing confusion and potential conflicts with other aircraft.

After continuing on the assigned route, a pilot will typically follow additional protocols which include squawking the proper transponder code, adhering to altitude restrictions as per the last communication, and attempting to re-establish communication. However, the initial step after losing communication is to respect the last directives given by ATC, which is why flying the assigned route is the correct answer.