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The Civil Aviation (Units of Measurement to be used in Air and Ground Operations), Regulations 2018

Legal Notice 120 of 2018

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The Civil Aviation (Units of Measurement to be used in Air and Ground Operations), Regulations 2018
Citation
Legal Notice 120 of 2018
Primary work
Civil Aviation Act
Date
31 December 2022
Language
English
Type
Legal Notice
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LAWS OF KENYA

CIVIL AVIATION ACT

THE CIVIL AVIATION (UNITS OF MEASUREMENT TO BE USED IN AIR AND GROUND OPERATIONS), REGULATIONS 2018

LEGAL NOTICE 120 OF 2018

  • Published in Kenya Gazette Vol. CXX—No. 69 on 8 June 2018
  • Commenced on 31 May 2018
  1. [Revised by 24th Annual Supplement (Legal Notice 221 of 2023) on 31 December 2022]

Part I – PRELIMINARY

1. Citation

These Regulations may be cited as the Civil Aviation (Units of Measurement to be used in Air and Ground Operations), Regulations.

2. Interpretation

In these Regulations, unless the context otherwise requires—“ampere (A)” means that constant electric current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in a vacuum, would produce between these conductors a force equal to 2 × 10-7 newton per metre of length;“becquerel (Bq)” means the activity of a radionuclide having one spontaneous nuclear transition per second;“candela (cd)” means the luminous intensity, in the perpendicular direction, of a surface of 1/600 000 square metre of black body at the temperature of freezing platinum under a pressure of 101 325 newtons per square metre;“celsius temperature (t°C)” means the Celsius temperature is equal to the difference t°C = T-T0 between two thermodynamic temperatures T and T0 where T0 equals 273.15 Kelvin;“coulomb (C)” means the quantity of electricity transported in 1 second by a current of 1 ampere;“degree celsius (°C)” means the special name for the unit Kelvin for use in stating values of Celsius temperature;“farad (F)” means the capacitance of a capacitor between the plates of which there appears a difference of potential of 1 volt when it is charged by a quantity of electricity equal to 1 coulomb;“foot (ft)” means the length equal to 0.3048 metre exactly;“gray (Gy)” means the energy imparted by ionizing radiation to a mass of matter corresponding to 1 joule per kilogram;“henry (H)” means the inductance of a closed circuit in which an electromotive force of 1 volt is produced when the electric current in the circuit varies uniformly at a rate of 1 ampere per second;“hertz (Hz)” means the frequency of a periodic phenomenon of which the period is 1 second;“human performance” means human capabilities and limitations which have an impact on the safety and efficiency of aeronautical operations;“joule (J)” means the work done when the point of application of a force of 1 Newton is displaced a distance of 1 metre in the direction of the force;“kelvin (K)” means a unit of thermodynamic temperature which is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water;“kilogram (kg)” means the unit of mass equal to the mass of the international prototype of the kilogram;“knot (kt)” means the speed equal to 1 nautical mile per hour;“International System of Units (SI)” means a complete, coherent system which includes three classes of unit’s base units, supplementary units; and derived units;“litre (L)” means a unit of volume restricted to the measurement of liquids and gases which is equal to 1 cubic decimeter;“lumen (lm)” means the luminous flux emitted in a solid angle of 1 steradian by a point source having a uniform intensity of 1 candela;“lux (lx)” means the illuminance produced by a luminous flux of 1 lumen uniformly distributed over a surface of 1 square metre;“metre (m)” means the distance travelled by light in a vacuum during 1/299 792 458 of a second;“mole (mol)” means the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12;“nautical mile (NM)” means the length equal to 1,852 metres exactly;“newton (N)” means the force which when applied to a body having a mass of 1 kilogram gives it an acceleration of 1 metre per second squared;“Ohm (Ω)” means the electric resistance between two points of a conductor when a constant difference of potential of 1 volt, applied between these two points, produces in this conductor a current of 1 ampere, this conductor not being the source of any electromotive force;“pascal (Pa)” means the pressure or stress of 1 newton per square metre;“radian (rad)” means the plane angle between two radii of a circle which cut off on the circumference an arc equal in length to the radius;“second (s)” means the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom;“siemens (S)” means the electric conductance of a conductor in which a current of 1 ampere is produced by an electric potential difference of 1 volt;“sievert (Sv)” means the unit of radiation dose equivalent corresponding to 1 joule per kilogram;“steradian (sr)” means the solid angle which having its vertex in the centre of a sphere, cuts off an area of the surface of the sphere equal to that of a square with sides of length equal to the radius of the sphere;“tesla (T)” means the magnetic flux density given by a magnetic flux of 1 weber per square metre;“tonne (t)” means the mass equal to 1 000 kilograms;“volt (V)” means the unit of electric potential difference and electromotive force which is the difference of electric potential between two points of a conductor carrying a constant current of 1 ampere, when the power dissipated between these points is equal to 1 watt;“watt (W)” means the power which gives rise to the production of energy at the rate of 1 joule per second;“weber (Wb)” means the magnetic flux which, linking a circuit of one turn, produces in it an electromotive force of 1 volt as it is reduced to zero at a uniform rate in 1 second.

3. Application

These Regulations shall apply to all aspects of civil aviation air and ground operations.

Part II – STANDARD APPLICATION OF UNITS OF MEASUREMENT

4. SI Units

(1)The International System of Units developed and maintained by the General Conference of Weights and Measures (CGPM) shall, subject to regulations 5 and 6, be used as the standard system of units of measurement for all aspects of civil aviation air and ground operations.
(2)The prefixes and symbols listed in Table 1 of the Schedule shall be used to form names and symbols of the decimal multiples and submultiples of SI units.

5. Non- SI Units alternative units permitted for temporary use with the SI

The non-SI units listed in Table 3 of the First Schedule shall be permitted for temporary use as alternative units of measurement but only for those specific quantities listed in Table 4.

6. Application of specific units

(1)The application of units of measurement for certain quantities used in civil aviation air and ground operations shall be in accordance with Table 4 of the first schedule of these regulations.
(2)In instances where the mole is used, the elementary entities shall be specified and may be atoms, molecules, ions, electrons, other particles or specified groups of such particles.

7. Design, procedures and training

The means and provisions for design, procedures and training shall be established for operations in environments involving the use of standard and non-SI alternatives of specific units of measurement, or the transition between environments using different units, with due consideration to human performance.

8. Use of alternative non-SI units

The use in civil aviation operations of the alternative non SI units (Knot, Nautical Mile and foot) shall be terminated on the dates to be established by International Civil Aviation.

9. Offence

Any violation to these Regulations shall be subject to the general penalty provisions as provided in section 80 of the Civil Aviation Act.

Schedule

 Table 1. SI unit prefixes
  Multiplication factorPrefixSymbol
1 000 000 000 000 000 000 = 1018exaE
1 000 000 000 000 000 = 1015petap
1 000 000 000 000 = 1012teraT
1000000 000 = 109gigaG
1000000 = 106megaM
1 000 = 103kilok
100 = 102hectoh
10 = 101decada
0.1 = 10-1decid
0.01 = 10-2centic
0.001 = 10-3millim
0.000 001 = 10-6microμ
0.000 000 001 = 10-9nanon
0.000 000 000 001 = 10-12picop
0.000 000 000 000 001 = 10-15femtof
0.000 000 000 000 000 001 = 10-18attoa
 Table 2. Non-SI units for use with the SI
Specific quantities in Table 3-4 related toUnitSymbolDefinition (in tenns of SI units)
masstonnet1 t= 103 kg
plane angledegree°10 = (π/180) rad
minute'11 = (i/ 60)0 = (π/10 800) rad
second"1" = (1/60)' = (π/648 000) rad
temperaturedegree Celsius°C1 unit °C = 1 unit Ka}
timeminutemin1 min= 60 s
hourhlh=60min=3600s
dayd1 d = 24 h = 86 400 s
week, month, year— 
volumelitreL1 L = 1 dm3 = 10-3 m3
 Table 3. Non-SI units for temporary use with the SI
Specific quantities in Table 3-4 related to UnitSymbolDefinition(in tenns of SI Units)
distance (long)nautical mileNMl NM = 1 852 m
distance (vertical)a)footft1 ft = 0.304 8 m
speedknotkt1 kt=0.514 444 m/s
a) altitude, elevation, height, vertical speed.   
Table 4. Standard application of specific units of measurement
Ref No.QuantityPrimary unit (symbol)Non-SI alternative unit (symbol)
1.Direction/Space/Time  
1.1altitudemft
1.2aream2 
1.3distance (long)a)kmNM
1.4distance (short)m 
1.5elevationmft
1.6enduranceh and min 
1.7heightmft
1.8latitude0 ' " 
1.9lengthm 
1.10longitude0 ' " 
1.11plane angle (when required, decimal subdivisions of the degree shall be used)0 
1.12runway lengthm 
1.13runway visual rangem 
1.14tank capacities (aircraft)b)L 
1.15time s
   min
   h
   d
   week
   month
   year
1.16visibilityc) km
1.17volume m3
1.18wind direction (wind directions other than for a landing and take-off shall be expressed in degrees true; for landing and takeoff wind directions shall be expressed in degrees magnetic) 0
2.Mass-related  
2.1air density kg/m3
2.2air density kg/m2
2.3cargo capacity kg
2.4cargo density kg/m3
2.5density (mass density) kg/m3
2.6fuel capacity (gravimetric) kg
2.7gas density kg/m3
2.8gross mass or payload kg
   t
2.9hoisting provisions kg
2.10linear density kg/m
2.11liquid density kg/m3
2.12mass kg
2.13moment of inertia kg . m2
2.14moment of momentum kg . m2/s
2.15momentum kg . m/s
3.Force-related  
3.1air pressure (general) kPa
3.2altimeter setting hPa
3.3atmospheric pressure hPa
3.4bending moment kN.m
3.5force N
3.6fuel supply pressure kPa
3.7hydraulic pressure kPa
3.8modulus of elasticity MPa
3.9pressure kPa
3.10stress MPa
3.11surface tension mN/m
3.12thrust kN
3.13torque N.m
3.14vacuum Pa
4.Mechanics  
4.1airspeedd) km/h
4.2angular acceleration rad/s2
4.3angular velocity rad/s
4.4energy or work J
4.5equivalent shaft power kW
4.6Frequency Hz
4.7groundspeed km/h
4.8Impact J/m2
4.9kinetic energy absorbed by brakes MJ
4.10linear acceleration m/s2
4.11Power kW
4.12rate of trim °/s
4.13shaft power kW
4.14Velocity m/s
4.15vertical speed m/s
5.Flow  
5.1engine airflow kg/s
5.2engine waterflow kg/h
5.3fuel consmnprion (specific)  
 piston engines kg/(kW · h)
 turbo-shaft engines kg/(kW · h)
 jet engines kg/(kN · h)
5.4fuel flow kg/h
5.5fuel rank filling rare (gravimetric) kg/min
5.6gas flow kg/s
5.7liquid flow (gravimetric) g/s
5.8liquid flow (volumetric) L/s
5.9mass flow kg/s
5.10oil consumption  
 gas turbine kg/h
 piston engines (specific) g/(kW · h)
5.11oil flow g/s
5. 12pump capacity L/min
5.13ventilation airflow m3/min
5.14viscosity (dynamic) Pa.s
5.15viscosity (kinematic) m2/s
6.Thermodynamics  
6.1coefficient of heat transfer W/(m2.K)
6.2hear flow per unir area J/m2
6.3hear flow rate W
6.4humidity (absolute) g/kg
6.5coefficient of linear expansion oC-1
6.6quantity of heat J
6.7temperature oC
7.Electricity and magnetism  
7.1capacitance F
7.2conductance S
7.3conductivity S/m
7.4current density A/m2
7.5electric cunent A
7.6electric field strength C/m2
7.7electric potential V
7.8electromotive force V
7.9magnetic field strength A/m
7.10magnetic flux Wb
7.11magnetic flux density T
7.12power W
7.13quantity of eleclticity C
7.14resistance Q
8.Light and related electromagnetic radiations  
8.1illuminance Ix
8.2luminance cd/m2
83luminous exitance Im/m2
8.4luminous flux Im
8.5luminous intensity cd
8.6quantity of light Im · s
8.7radiant energy J
8.8wavelength m
9.Acoustics  
9.1frequency Hz
9.2mass density kg/m3
9.3noise level dBe)
9.4period, periodic time s
9.5sound intensity W/m2
9.6sound power W
9.7sound pressure Pa
9.8sound level dBf)
9.9static pressure (instantaneous) Pa
9.10velocity of sound m/s
9.11volume velocity (instantaneous) m3/s
9.12wavelength m
10.Nuclear physics and ionizing radiation  
10.1absorbed dose Gy
10.2absorbed dose rate Gy/s
10.3activity of radionuclides Bq
10.4dose equivalent Sv
10.5radiation exposure C/kg
10.6exposure rate C/kg .s
a) As used in navigation generally in excessof 4 000 m.b) Such as aircraft fuel, hydraulic fluids, water, oil and high pressure oxygen vessels.c) Visibility of less than 5 km may be given in m.d) Airspeed is sometimes reported in flight operations in terms of the ratio MACH number.e) A conversion of 1 kt = 0.5 m/s is used in ICAO Annexes for the representation of wind speed.f) The decibel (dB) is a ratio which may be used as a unit for expressing sound pressure level and sound power level. When used, the reference level must be specified.
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History of this document

31 December 2022 this version
08 June 2018
31 May 2018
Commenced