How should an aerodrome elevation of 350 feet be expressed in radio communication?

In radio communication, it is essential to express aerodrome elevation clearly and concisely, especially in operational contexts where clarity can affect safety and operations. The correct answer, expressing "Field elevation three fifty," adheres to the standard phraseology used in aviation communications.

In this context, "Field elevation" indicates the specific altitude of the aerodrome relative to sea level, which is crucial information for pilots when approaching or departing from the aerodrome. Using "three fifty" is also a typical shorthand way to convey the altitude, avoiding awkward phrasing.

Other options may not be as precise or conventional in aviation communication. For instance, stating "Aerodrome level is 350" doesn't follow the preferred terminology and could lead to ambiguity. "Field elevation one three zero" is incorrect as it references a false elevation, which could lead to confusion. Lastly, saying "Three hundred fifty feet above sea level," while technically accurate, is often avoided in favor of more concise phrasing in radiotelephony. Therefore, "Field elevation three fifty" is the most appropriate and widely understood way to communicate the aerodrome elevation of 350 feet.