8/15/19 1/30/20  Pilot/Controller Glossary Pilot/Controller Glossary  traffic rules, unless otherwise authorized by air traffic  control. Not all areas listed in 14 CFR Part 93 are  designated SFRA, but special air traffic rules apply to  all areas described in 14 CFR Part 93.  SPECIAL USE AIRSPACE- Airspace of defined  dimensions identified by an area on the surface of the  earth wherein activities must be confined because of  their nature and/or wherein limitations may be  imposed upon aircraft operations that are not a part of  those activities. Types of special use airspace are:  (See INSTRUMENT APPROACH PROCEDURE.)  a.  Alert Area- Airspace which may contain a high  volume of pilot training activities or an unusual type  of aerial activity, neither of which is hazardous to  aircraft. Alert Areas are depicted on aeronautical  charts for the information of nonparticipating pilots.  All activities within an Alert Area are conducted in  accordance with Federal Aviation Regulations, and  pilots of participating aircraft as well as pilots  transiting the area are equally responsible for  collision avoidance.  b.  Controlled Firing Area- Airspace wherein  activities are conducted under conditions so  controlled as to eliminate hazards to nonparticipating  aircraft and to ensure the safety of persons and  property on the ground.  c.  Military Operations Area (MOA)- Permanent  and temporary MOAs are airspace established  outside of Class A airspace area to separate or  segregate certain nonhazardous military activities  from IFR traffic and to identify for VFR traffic where  these activities are conducted. Permanent MOAs are  depicted on Sectional Aeronautical, VFR Terminal  Area, and applicable En Route Low Altitude Charts.  Note: Temporary MOAs are not charted.  (Refer to AIM.)  d.  Prohibited Area- Airspace designated under  14 CFR Part 73 within which no person may operate  an aircraft without the permission of the using  agency.  (Refer to AIM.)  (Refer to En Route Charts.)  e.  Restricted Area- Permanent and temporary  restricted areas are airspace designated under 14 CFR  Part 73, within which the flight of aircraft, while not  wholly prohibited, is subject to restriction. Most  restricted areas are designated joint use and IFR/VFR  operations in the area may be authorized by the  controlling ATC facility when it is not being utilized  by the using agency. Permanent restricted areas are  depicted on Sectional Aeronautical, VFR Terminal  Area, and applicable En Route charts. Where joint  use is authorized, the name of the ATC controlling  facility is also shown.  Note: Temporary restricted areas are not charted.  (Refer to 14 CFR Part 73.)  (Refer to AIM.)  f.  Warning Area- A warning area is airspace of  defined dimensions extending from 3 nautical miles  outward from the coast of the United States, that  contains activity that may be hazardous to  nonparticipating aircraft. The purpose of such  warning area is to warn nonparticipating pilots of the  potential danger. A warning area may be located over  domestic or international waters or both.  SPECIAL VFR CONDITIONS- Meteorological  conditions that are less than those required for basic  VFR flight in Class B, C, D, or E surface areas and  in which some aircraft are permitted flight under  visual flight rules.  (See SPECIAL VFR OPERATIONS.)  (Refer to 14 CFR Part 91.)  SPECIAL VFR FLIGHT [ICAO]- A VFR flight  cleared by air traffic control to operate within Class  B, C, D, and E surface areas in metrological  conditions below VMC.  SPECIAL VFR OPERATIONS- Aircraft operating  in accordance with clearances within Class B, C, D,  and E surface areas in weather conditions less than the  basic VFR weather minima. Such operations must be  requested by the pilot and approved by ATC.  (See SPECIAL VFR CONDITIONS.)  (See ICAO term SPECIAL VFR FLIGHT.)  SPEED- (See AIRSPEED.)  (See GROUND SPEED.)  SPEED ADJUSTMENT- An ATC procedure used to  request pilots to adjust aircraft speed to a specific  value for the purpose of providing desired spacing.  Pilots are expected to maintain a speed of plus or  minus 10 knots or 0.02 Mach number of the specified  speed. Examples of speed adjustments are:  a.  “Increase/reduce speed to Mach point  (number).”  PCG S-6  SPECIAL INSTRUMENT APPROACH PROCE- DURE-