Reciprocal Headings A reciprocal heading is the exact opposite direction — 180° away. You'll use this constantly: holding entries, intercepting courses, backtracking, and more. This rule is used almost every single time you fly, especially in IFR scenarios with courses TO and radials FROM, this quick mental math trick will save you so much time and headaches. +2 -2 Say your heading is 180, add 'two' to the first digit and subtract 'two' from the second digit, so 1 plus 2 is 3, and 8 minus 2 is 6, and we leave the third digit alone, so your answer is 3-6-0 which is the exact opposite heading as 180. Again, say your heading is 045, lets add two to the first digit and subtract two from the second and we get 2-2-5, which is the reciprocal heading! If your number starts with a 3, like the heading 327, just do the opposite and subtract two from the first digit and add two to the next one, so we now have 3-2=1 and 2+2=4, leaving the last digit alone and we now have a reciprocal heading of 147! The math behind this is you want to add or subtract 180 degrees, but to make the math easier you just add 200 and subtract 20, or vice versa (if your number is too big) of subtracting 200 and adding 20 back to it. Lets try some more... 090 - plus two since you cant subtract two from zero, then minus two from the next digit = 270 360 - Since you can't add two, start by subtracting first, and adding second, to get = 180 198 - 307 - 144 - 280 - Sometimes it's literally just easier to subtract 180 from it, don't overcomplicate things

Hello team, My aviation journey: USAF Aerospace Physiology; I taught classes on aircraft pressurization, life support, hypoxia and more. I performed various roles in/outside altitude chamber operations. Participated in an exchange with the USN Aviation Physiology, which included helo dunkers, HEEDS bottle obstacle courses, ocean water survival, parachute escape, water retrieval and more. I've logged time as a student pilot in fixed-wing single engine Cessna's 150/2/172, Piper Cherokee, performing solo cross-country flights. I've taken the majority of the classes offered for an 'aviation science' associates degree, which included meteorology, laws & regs, systems and structures, aerodynamics. I've been out of the flying world for a while, but it's still in my blood.