Timeline for Why does a steeper approach cause an increased landing rollout?
Current License: CC BY-SA 3.0
7 events
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| Sep 21, 2017 at 6:21 | comment | added | Jan Hudec | @Adwaenyth, also, approaches are generally flown on the back of the power curve. Increasing speed decreases drag! This is because drag has the induced component, which decreases with (square of) speed and therefore there is certain speed at which drag is minimal. Extending flaps decreases that speed, but not below Vref in most aircraft. So you would have to be a lot faster to increase drag and you can't do that, because you must be slow for landing. | |
| Sep 21, 2017 at 6:17 | comment | added | Jan Hudec | @Adwaenyth, remember, we are talking about powered approach. If you descend faster, more energy is converted from potential, so less energy is converted from fuel. | |
| Sep 20, 2017 at 12:01 | comment | added | Adwaenyth | @JanHudec from a pure physical point of view energy is retained. If you descend faster, more energy is converted from potential energy to kinetic energy. The only way to shed that energy is via drag. Drag is depending on velocity. So unless you are pretty fast, drag will not compensate for a larger speed increase. | |
| Sep 20, 2017 at 10:43 | comment | added | Sanchises | Unless your aircraft has an minimal L/D in landing configuration (including air brakes) such that the increased glideslope results in a higher speed than Vref with engines idle, I see no reason for a higher landing airspeed. As for C, the pilot is following the VASI, which guides the pilot to a fixed point on the runway (excluding flare). Under the assumption that the pilot follows the VASI, they have no choice where to land. | |
| Sep 20, 2017 at 1:54 | vote | accept | lemonincider | ||
| Sep 19, 2017 at 18:21 | comment | added | Jan Hudec | Why would you be faster? Is it for safety reason? And is it actually included in typical Vref calculation? | |
| Sep 19, 2017 at 15:55 | history | answered | Sebo | CC BY-SA 3.0 |