Which value represents the maximum speed with the windows open?

Which value represents the maximum speed with the windows open?

• A. 149 knots
• B. 104 knots
• C. 95 knots
• D. 70-80 knots

Answer: (A)

Opening a window changes the loads and airflow around the airframe. The extra ventilation air creates drag and puts bending and shear forces on the window frame and latching hardware. The aircraft is designed to tolerate these loads only up to a certain speed, and for this configuration that limit is about 149 knots indicated. Going faster than that increases the risk of window or seal failure, window blowout, and disruptive wind blast inside the cabin, which can affect control and comfort. So the maximum safe speed with the window open is 149 knots. The other lower speeds would be safe but not the maximum for this configuration.

Opening a window changes the loads and airflow around the airframe. The extra ventilation air creates drag and puts bending and shear forces on the window frame and latching hardware. The aircraft is designed to tolerate these loads only up to a certain speed, and for this configuration that limit is about 149 knots indicated. Going faster than that increases the risk of window or seal failure, window blowout, and disruptive wind blast inside the cabin, which can affect control and comfort. So the maximum safe speed with the window open is 149 knots. The other lower speeds would be safe but not the maximum for this configuration.