During my ground school with sporty’s, there is a density altitude chart that is confusing. Can someone please explain this to me? I’m having trouble with it.
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If you’ve already calculated the Pressure Altitude, you simply get your OAT and draw a line up to the pressure altitude you calculated. From there draw another line from that point to the left of the chart and that’ll give you Density Height
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I’m sure there are clearer explanations. But thought I’d try to wing it (no pun):
Upward slope of pressure lines is the stark picture of higher temp making the aircraft feel higher (less airfoil and engine bite). Upward slope says, you thought you were here, but your airplane feels like it’s there. Higher the temp, worse it gets.
As temperatures decline regularly with altitude, a standard temp defined at sea level has to decline as you go higher (redline leans left).
Temp higher than standard makes you feel higher - grey lines go up to the right of red line; Temp lower than standard makes you feel lower - lines go down to the left of red line.
Conversion factor. The atmosphere is a staircase (predictable layering) of pressure and temperature decline with height. Changes in weather don’t erase the staircase, but move the entire staircase up and down. The staircase placement needs a home starting point (average over time is the best choice): altimeter pressure of 29.92 Any difference in actual sea level pressure translates to an altitude factor to move the “floor of the staircase,” to remove the error caused by weather fluctuations.
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PM me. Certified ground instructor here. I’ll explain it to you. :)
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Handling via pm