Ram air inlets for use with aircraft environmental control systems and other aircraft and non-aircraft systems are described herein. In one embodiment, a ram air inlet configured in accordance with the present invention includes an inlet lip spaced apart from an inlet housing. An inlet door is moveably attached to the inlet housing, and includes a first surface portion, a second surface portion, and a transition region extending between the first and second surface portions. The first surface portion is moveably positioned at least approximately forward of the inlet lip. The second surface portion is fixed at an angle relative to the first surface portion, and is moveably positioned at least approximately aft of the inlet lip. The transition region is positioned at least approximately adjacent to the inlet lip to form an inlet opening therebetween. Movement of the inlet door in a first direction reduces the size of the inlet opening to thereby decrease the flow of ram air through the inlet. Conversely, movement of the inlet door in a second direction enlarges the inlet opening to increase the flow of ram air through the inlet.