I have a Kestrel that I use to get my DA. I then put the DA into Ballistic AE which also asks me for the Temp or Mach. Here's my question. DA is calculated as: Pressure Altitude + [120 x (OAT - ISA Temp)] OAT is local temperature from a thermometer. ISA Temp is always 15 °C at sea level. From that formula, it looks like DA includes temperature already. Why is Ballistic AE asking for Temp. again?