Calculating slope takeoff distance for C172
Hi everyone,
I have a question. I'm flying the Cessna 172. I wanted to know if there is a formula to calculate how much distance is needed to add or subtract regarding runway slope. I know how to obtain the runway slope gradient. I just need to know how.
For example, I was fooling around with Jeppesen FliteMap which has a takeoff distance calculator. KLVK (400 ft), Runway 25R (5253 feet) has a downslope of 0.5% which Jeppesen say it decrease the takeoff distance by 43 feet, assuming the temp in KLVK is 14C and winds calm. how did Jeppesen calculate that?
Information for KLVK
Density altitude of 400 feet
has added 78 to the standard takeoff distance.
Runway 25R (5253 feet) takeoff distance is 1665 feet.
0.5% downslope has decreased your
takeoff distance by 43 feet.