Pilot/Controller Glossary STATIONARY ALTITUDE RESERVATION (STATIONARY ALTRV)" An altitude reservation which encompasses activities in a fixed volume of airspace to be occupied for a specified time period. Stationary ALTRVs may include activities such as special tests of weapons systems or equipment; certain U.S. Navy carrier, fleet, and anti-submarine operations; rocket, missile, and drone operations; and certain aerial refueling or similar operations. STEP TAXI- To taxi a float plane at full power or high RPM. STEP TURN- A maneuver used to put a float plane in a planing configuration prior to entering an active sea lane for takeoff. The STEP TURN maneuver should only be used upon pilot request. STEPDOWN FIX- A fix permitting additional descent within a segment of an instrument approach procedure by identifying a point at which a controlling obstacle has been safely overflown. STEREO ROUTE- A routinely used route of flight established by users and ARTCCs identified by a coded name; e.g., ALPHA 2. These routes minimize flight plan handling and communications. STNR ALT RESERVATION" An abbreviation for Stationary Altitude Reservation commonly used in NOTAMs. (See STATIONARY ALTITUDE RESERVATION.) STOL AIRCRAFT- (See SHORT TAKEOFF AND LANDING AIRCRAFT.) STOP ALTITUDE SQUAWK- Used by ATC to instruct a pilot to turn off the automatic altitude reporting feature of the aircraft transponder and ADS-B Out. It is issued when a verbally reported altitude varies by 300 feet or more from the automatic altitude report. (See ALTITUDE READOUT.) (See TRANSPONDER.) STOP AND GO- A procedure wherein an aircraft will land, make a complete stop on the runway, and then commence a takeoff from that point. (See LOW APPROACH.) (See OPTION APPROACH.) STOP BURST- (See STOP STREAM.) STOP BUZZER- (See STOP STREAM.) STOP SQUAWK (Mode or Code)- Used by ATC to instruct a pilot to stop transponder and ADS-B transmissions, or to turn off only specified functions of the aircraft transponder (military). (See STOP ALTITUDE SQUAWK.) (See TRANSPONDER.) STOP STREAM- Used by ATC to request a pilot to suspend electronic attack activity. (See JAMMING.) STOPOVER FLIGHT PLAN- A flight plan format which permits in a single submission the filing of a sequence of flight plans through interim full-stop destinations to a final destination. STOPWAY- An area beyond the takeoff runway no less wide than the runway and centered upon the extended centerline of the runway, able to support the airplane during an aborted takeoff, without causing structural damage to the airplane, and designated by the airport authorities for use in decelerating the airplane during an aborted takeoff.