ATC 용어집 (m)

1. Mach No - The ratio of true airspeed to the speed of sound

활용) Mach No이 1이하인 경우 Mach No 0.5 Mach point five, Mach No 1.5 One Point five

2. MAINTAIN-

a. Concerning altitude/flight level, the term means to remain at the altitude/flight level specified. The phrase "climb and" or "descend and" normally precedes "maintain" and the altitude assignment; e.g., "descend and maintain 5,000."

b. Concerning other ATC instructions, the term is used in its literal sense; e.g., maintain VFR.

활용) 한 가지 고도만 유지, 상승 후 얼마를 유지하세요, 하강후 얼마를 유지하세요, VFR을 유지하세요

ATC : Climb and maintain 6,000/ Climb and maintain 4,000 / Maintain VFR

(cf) Cruise

Tip) VFR 유지 Wx minimum : Airspace 별로 조금씩 차이가 있음

Control airspace의 기본 : 구름으로부터 거리와 visibility

구름으로부터 거리 : 위로 1,000ft 아래로 500ft 옆으로 2,000ft

Visibility : 3sm(statue mile)

3. MAYDAY- The international radiotelephony distress signal. When repeated three times, it indicates imminent and grave danger and that immediate assistance is requested.

활용) mayday call은 평생 안하는 것!!!, Emergency Frequency는 7700

Tip) Emergency ABC

A : best glide air speed - 가장 멀리갈수 있는 속도 (고도가 생명, 기수를 약간 받쳐준다)

B : best emergency site - gliding performance를 고려해서 갈수 있는 반경

e.g. Mooney의 경우 1000ft 에 2miles

C : Cockpit management ? - 시간의 여유가 생겨 한번 살려보겠다는 노력

해보고 나서 squawk 7700을 맞추고 Frequency in use한다(무조건 비상주파수는 아니다)

비상 착륙시에는 mixture cut off하고 전기 계통도 다 끈다. 허나 플랩, 기어, 문만 열어 놓고 남겨두고 나머지는 다 끈다. 착륙시에 문등이 Jam되어 열리지 않을 수 있다.

4. MAKE SHORT APPROACH(Final) - Used by ATC to inform a pilot to alter his/her traffic pattern so as to make a short final approach.

활용) Separation시 사용하는 용어.

(cf) extend downwind

5. Make (방향) Three Sixty = Make Orbit (방향) = Make anchor (방향)

활용) 360도 선회하세요, 한 바퀴 도세요

ATC : make left three sixty : '왼쪽으로 한 바퀴 도세요' 처럼 방향을 지정해 주기도 한다.

Tip) 군 : starboard = right turn / port = left turn

ATC : orbit starboard / orbit port

Anchor = Orbit : anchor와 orbit이 정확히 같지는 않음, 허나 거의 동일한 의미로 사용

Anchor : 어떤 상황에서도 정확한 원을 그려서 선회

Orbit : 한 바퀴 선회만하라 정확한 원을 그리지는 않아도 됨

6. Minimum / Maximum Altitude

1) MOCA (Minimum Obstruction Clearance Altitude) : Radio를 켰을 때 Signal을 잡을 수 있는 고도

Tip) MINIMUM OBSTRUCTION CLEARANCE ALTITUDE (MOCA)- The lowest published altitude in effect between radio fixes on VOR airways, off-airway routes, or route segments which meets obstacle clearance requirements for the entire route segment and which assures acceptable navigational signal coverage only within 25 statute (22 nautical) miles of a VOR.

2) MEA (Minimum En route Altitude) : MOCA + Airway 전 구간에서 NAV Signal을 잡을 수 있는 고도

Tip) MINIMUM EN ROUTE IFR ALTITUDE (MEA)- The lowest published altitude between radio fixes which assures acceptable navigational signal coverage and meets obstacle clearance requirements between those fixes. The MEA prescribed for a Federal airway or segment thereof, area navigation low or high route, or other direct route applies to the entire width of the airway, segment, or route between the radio fixes defining the airway, segment, or route.

3) MCA (Minimum Crossing Altitude) : 해당 FIX를 일정 고도로 통과, 항공기의 Performance를 고려하여 도착 전부터 상승해야 한다

(cf) MCA가 설정 되어 있지 않을 경우에는 Fix에 도착한 이후에 고도를 상승한다

Tip) MINIMUM CROSSING ALTITUDE- The lowest altitude at certain fixes at which an aircraft must cross when proceeding in the direction of a higher minimum en route IFR altitude (MEA).

4) MRA (Minimum Reception Altitude) : 해당 Airway에 있는 Fix를 ID내는 데에 있어 Off Course 로부터의 NAVAID로부터 항로상의 Fix ID를 내기 위한 최저고도

Tip) MINIMUM RECEPTION ALTITUDE- The lowest altitude at which an intersection can be determined.

5) MAA (Maximum Authorized Altitude) : 동일주파수로 인해 주파수 혼선을 방지하여 VOR Signal을 받을 수 있는 최대고도

(cf) 국내에서는 모든 VOR이 다른 주파수를 사용한다. → MAA 존재 X

6) MHA (Minimum Holding Altitude) : Radio Communication, Radio Signal, Clear of Obstacle, 도착 지연이 예상될 때 먼저 온 항공기를 가장 낮은 고도에 위치시키는데 이때의 고도

Tip) MINIMUM HOLDING ALTITUDE- The lowest altitude prescribed for a holding pattern which assures navigational signal coverage, communications, and meets obstacle clearance requirements.

7) MVA (Minimum Vectoring Altitude) : 관제사가 Vectoring할 때 안전을 위한 최저고도 (조종사는 알수 없다)

Tip) MINIMUM VECTORING ALTITUDE (MVA)- The lowest MSL altitude at which an IFR aircraft will be vectored by a radar controller, except as otherwise authorized for radar approaches, departures, and missed approaches. The altitude meets IFR obstacle clearance criteria. It may be lower than the published MEA along an airway or J-route segment. It may be utilized for radar vectoring only upon the controller's determination that an adequate radar return is being received from the aircraft being controlled. Charts depicting minimum vectoring altitudes are normally available only to the controllers and not to pilots.

8) MSA (Minimum Safe/Sector Altitude) : Navigation facility 기준 반경 25mile 이내 장애물로부터 1000ft 이상 Clear 한 최저고도. Emergency에 사용

Tip) MINIMUM SAFE ALTITUDE-

a. The minimum altitude specified in 14 CFR Part 91 for various aircraft operations.

b. Altitudes depicted on approach charts which provide at least 1,000 feet of obstacle clearance for emergency use within a specified distance from the navigation facility upon which a procedure is predicated. These altitudes will be identified as Minimum Sector Altitudes or Emergency Safe Altitudes and are established as follows:

1. Minimum Sector Altitudes. Altitudes depicted on approach charts which provide at least 1,000 feet of obstacle clearance within a 25-mile radius of the navigation facility upon which the procedure is predicated. Sectors depicted on approach charts must be at least 90 degrees in scope. These altitudes are for emergency use only and do not necessarily assure acceptable navigational signal coverage.

(See ICAO term Minimum Sector Altitude.)

2. Emergency Safe Altitudes. Altitudes depicted on approach charts which provide at least 1,000 feet of obstacle clearance in nonmountainous areas and 2,000 feet of obstacle clearance in designated mountainous areas within a 100-mile radius of the navigation facility upon which the procedure is predicated and normally used only in military procedures. These altitudes are identified on published procedures as "Emergency Safe Altitudes."

7. MISSED APPROACH-

a. A maneuver conducted by a pilot when an instrument approach cannot be completed to a landing. The route of flight and altitude are shown on instrument approach procedure charts. A pilot executing a missed approach prior to the Missed Approach Point (MAP) must continue along the final approach to the MAP.

b. A term used by the pilot to inform ATC that he/she is executing the missed approach.

c. At locations where ATC radar service is provided, the pilot should conform to radar vectors when provided by ATC in lieu of the published missed approach procedure.

활용) 실패 접근이 아니라 정상적인 접근이나 기상등의 이유로 Go-around 한 경우

8. MODE- The letter or number assigned to a specific pulse spacing of radio signals transmitted or received by ground interrogator or airborne transponder components of the Air Traffic Control Radar Beacon System (ATCRBS). Mode A (military Mode 3) and Mode C (altitude reporting) are used in air traffic control