Yes, pilots are allowed to sleep during flights, but it is a highly regulated and structured safety procedure rather than an informal nap. On long-haul flights, aircraft are often "augmented" with a third or fourth pilot, allowing them to take turns sleeping in dedicated crew rest compartments (bunks) while the other two pilots remain at the controls. On shorter flights, pilots may use "Controlled Rest in the Cockpit." This allows one pilot to take a short nap (typically 10–20 minutes) while the other pilot maintains full control of the aircraft. This is designed to combat "micro-sleeps" and ensure the crew is fully alert for the critical landing phase. This rest is only permitted during the "cruise" phase of the flight when workload is low, and it must be agreed upon by both pilots. Both pilots are strictly prohibited from sleeping at the same time; one must always be awake and actively monitoring the systems.