What Mode 1 squawk indicates desire tanker to join?

The squawk code that indicates a desire for a tanker to join is 70. This specific code is used in the context of air-to-air refueling operations to signal the intention of an aircraft to initiate a join-up for refueling with a tanker aircraft. Recognizing and using the correct squawk code is critical for ensuring clear communication and coordination between aircraft during refueling operations.

In the realm of air traffic control and military operations, squawk codes are essential for identifying aircraft and their intentions. The other squawk codes listed do not have designated meanings related to joining a tanker for refueling, making 70 the specific and appropriate choice for this scenario. Understanding these codes helps pilots and air traffic controllers efficiently manage inflight refueling processes and maintain a safe and organized airspace.