Centaurus
12th May 2009, 13:53
Recent discussion on flap non-normals reminded me of a paragraph in the FCTM (since deleted I presume because I could find no reference to it anymore) that recommended one moveable white airspeed bug be set to the current Flap Five manoevering speed. B737-300 EFIS.
For the life of me I cannot remember for what situation that was required. It might have been a windshear precaution take off or possibly a non-normal flap operation, but I am certain it was somewhere in the FCTM. A colleague also vaguely recalls the recommendation but other experienced 737 pilots I know have not heard of the techique.
The discussion was about the setting of a single moveable airspeed bug at Vref + 15 knots during the ASI set up for a trailing edge flaps up landing. Is it correct to set one bug at Vref +15 in this configuration? Vref for this config is Vref 40 plus 40 knots. At 48,000 kgs this worked out as 170 knots Vref. In other words does Boeing require a single bug at 185 knots (Vref plus 15). If so, why?
For the life of me I cannot remember for what situation that was required. It might have been a windshear precaution take off or possibly a non-normal flap operation, but I am certain it was somewhere in the FCTM. A colleague also vaguely recalls the recommendation but other experienced 737 pilots I know have not heard of the techique.
The discussion was about the setting of a single moveable airspeed bug at Vref + 15 knots during the ASI set up for a trailing edge flaps up landing. Is it correct to set one bug at Vref +15 in this configuration? Vref for this config is Vref 40 plus 40 knots. At 48,000 kgs this worked out as 170 knots Vref. In other words does Boeing require a single bug at 185 knots (Vref plus 15). If so, why?