Whenever you open a tower frequency at an airport, do you take note of your transition altitude?
Often overlooked, transition altitude is still important to know off the top of your head for your specific airfield. One of the first things I do before or when I open is determine my airfield’s transition altitude by using the well-known transition altitude formula: 2500ft AAL rounded up to the nearest 500 feet. Why? A transition is when an aircraft flies through your tower airspace, or innermost circle on the map, but above your pattern. Pattern altitude is 2500 feet AAL at a minimum so that transition aircraft are 1000 feet above pattern aircraft at either 1000 or 1500 feet AGL, so that they still maintain separation with pattern aircraft. This is then rounded up to the nearest 500, as it is rare to have an airfield be at a perfect 0 or 500. For example, if your airfield’s elevation is 542ft MSL, your transition altitude would be 3500ft MSL.
Always know your transition altitude every time you open a tower frequency.