For IFR aircraft, what information must be forwarded to non-approach control towers to adjust traffic flow?

The correct choice is based on the need for effective coordination between air traffic control sectors, especially when dealing with IFR (Instrument Flight Rules) aircraft. Non-approach control towers require specific information to ensure safe and efficient traffic flow, particularly during approaches and landings. The type of approach and estimated time of arrival (ETA) are essential details that help towers anticipate incoming traffic and manage runway assignments accordingly.

The type of approach indicates what procedures will be used for landing, which can affect how the tower prioritizes incoming aircraft and sequences them for a safe landing. Additionally, the ETA provides a timeline for when the aircraft is expected to reach the airport, allowing controllers to plan and make necessary adjustments to accommodate other traffic in the airspace. This information is vital for maintaining safety and efficiency in busy air traffic environments.

While the other options provide useful information, they do not encapsulate the critical elements needed for adjusting traffic flow in the way that the type of approach and ETA do. Current weather conditions, position during takeoff, and altitude and speed are also important, but they serve specific roles that are not directly aimed at coordinating traffic flow adjustments in the same way.