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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