ENR 1.7 ALTIMETER SETTING PROCEDURES

 

1.7.1 INTRODUCTION

The altimeter setting procedures in use generally conform to those contained in ICAO Doc 8168, Vol. I, Part 2 and are given in full below. QNH reports and temperature information for use in determining adequate terrain clearance are provided in MET broadcasts and are available on request from the air traffic services units. QNH values are given in hectopascals.

1.7.2 BASIC ALTIMETER SETTING PROCEDURES

  1. General
  1. In Taipei FIR, the transition altitude is 11000FT and the transition level is flight level 130.
  2. For mountainous area, disregarding the change in atmospheric pressure, the lowest usable flight level is FL160. This area lies north of 2230N and in the enclosure by landside boundaries of Taipei, Kaohsiung, Hualien and Taitung terminal control areas, see ENR 6, "Taipei FIR En Route Chart".
  3. Vertical positioning of aircraft when at or below the transition altitude is expressed in terms of altitude whereas such positioning at or above the transition level is expressed in terms of flight levels. While passing through the transition layer, vertical positioning is expressed in terms of altitude when descending, and in terms of flight levels when ascending.
  4. To ensure adequate terrain clearance, available weather information for determination of the lowest flight level will be provided by ATC units on request for flight planning and for aircraft in flight.
  5. If a change in atmospheric pressure affects a usable flight level in this area, Taipei Area Control Center will use the following table to determine the lowest usable flight level to clear aircraft at or above 13000FT MSL.
Table - Lowest Usable Flight Level
高度表撥定值
Altimeter Setting 		最低可使用空層
Lowest usable flight level
979.3百帕 (28.92英吋) 或以上
979.3 hPa (28.92 inches) or higher 		130
979.0-945.5百帕(28.91英吋至27.92英吋)
979.0-945.5 hPa (28.91 inches~27.92 inches) 		140
  1. Flight level zero shall be located at the atmospheric pressure level of 1013.2 hPa (29.92 inches). Consecutive flight levels shall be separated by a pressure interval corresponding to 500FT (152.4M) in the Standard Atmosphere.
 
Examples of the relationship between flight levels and altimeter indications are given in the following table, the metric equivalents being approximate:
飛航空層
Flight Level 		高度表指示
Altimeter Indication
Number
數字 		呎
Feet 		公尺
Meters
-90 -1000 -300
-95 -500 -150
0 0 0
5 500 150
10 1000 300
15 1500 450
20 2000 600
50 5000 1500
100 10000 3050
150 15000 4550
200 20000 6100
  1. Take-off and Climb
    1. A QNH altimeter setting shall be made available to aircraft in the routine take-off and climb instructions.
    2. Vertical positioning of aircraft during climb is expressed in terms of altitudes until reaching the transition altitude above which vertical positioning is expressed in terms of flight levels.
  2. Approach and Landing
    1. A QNH altimeter setting shall be made available in the routine approach and landing instructions.
    2. A QFE altimeter setting will be made available in the landing instructions on request from the aircraft.
    3. Vertical positioning of aircraft during approach is controlled by reference to flight levels at or above the transition level and by reference to altitude at or below the transition altitude.
  3. En-Route Transition Procedures-Flight Levels to Altitudes and Vice Versa
    The transition from flight levels to altitudes and vice versa while en route shall be made at the FIR boundary.
  4. Altimeter Setting Procedures
    1. Altimeter Setting Procedure in Terminal Control Areas and in the vicinity of aerodromes:
      Aircraft operating in Taipei, Kaohsiung, Kinmen, Hualien, Taitung, Matsu Terminal Control Areas shall use the QNH of Taipei/Taiwan Taoyuan, Kaohsiung, Kinmen, Hualien, Taitung/Fongnian, Matsu/Nangan Aerodromes respectively. Departure aircraft shall use the QNH of departure aerodrome. After departing from controlled airspace, or the traffic patterns of the departure aerodrome, aircraft shall use the above mentioned QNH in respective terminal control areas. Arriving aircraft shall use the above-mentioned QNH in respective terminal control areas, then when entering the controlled airspace or the traffic patterns of the destination aerodrome, use the QNH of the destination aerodrome.
    2. Altimeter Setting Procedure for operating outside the above areas:
      A line by connecting the following 6 points is the basic line which defines the north airspace and south airspace of Taipei FIR.
      244406.22N 1184713.69E
      240325.23N 1195202.28E
      235010.83N 1204634.06E
      232500N 1211818E
      232500N 1215442.95E
      240201N 1240000E
      All air traffic in the north airspace operating at or below the transition altitude will use Taipei/Taiwan Taoyuan International Aerodrome QNH, while all air traffic in the south airspace operating at or below the transition altitude, will use Kaohsiung Aerodrome QNH.

1.7.3 DESCRIPTION OF ALTIMETER SETTING REGION

NIL

1.7.4 PROCEDURES APPLICABLE TO OPERATORS (INCLUDING PILOTS)

  1. Flight Planning
    The levels at which a flight is to be conducted shall be specified in a flight plan;
    1. In terms of flight levels if the flight is to be conducted at or above the transition level.
    2. In terms of altitudes if the flight is to be conducted at or below the transition altitude.