Basic Aerodynamics / Trigonometry for Pilots. Flare Distance. How much real estate should
Photo: KTEB Rwy 06 Flight Path Vector and 3 ° Line, from Tom ' s notes.
We all agree that aiming for
“ brick one” is a bad idea and when we see someone else do it, we shake our heads and give a little tsk, tsk. Of course, when we aim for brick one, well that is just superior airmanship. Right? I grew up aiming for brick one and once in the B-737 got that nonsense beaten out of me. There are several issues here: Runway Markings. What do those hash marks mean to you, the pilot? The answer depends on the size of the runway and there are minor variations depending on what country you are in. In just about every case on a runway long enough for a jet, the runway aim point will be around 1,000 feet down the runway and the touchdown zone markers occur every
500 feet. Look Down Angle. Where
will your wheels touch the runway in relation to your aim point?( If you don ' t flare.) In a G450 the answer is 300 feet before the aim point for a 3 degree glide path. But the pilot ' s eyes are only 40 feet ahead of the wheels. How can this be? The answer lies with angles. More about this:
a flare take? Of course this depends heavily on pilot technique but there is an answer: it shouldn’ t take more distance than necessary. Some aircraft may specify a touchdown rate or other metric which makes the flight manual performance numbers possible. Most of this comes from the references listed at the bottom of the page, but a lot of the math and opinion is just mine, shown in blue. Runway threshold markings come in two configurations. They either consist of eight longitudinal stripes of uniform dimensions disposed symmetrically about the runway centerline, as shown in [ the figure ], or the number of stripes is related to the runway width
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