AllWeather Operations		5

Visual Reference

For Category IIIA and Category IIIB operations conducted either with fail passive flight control systems, or with the use of an approved HUDLS, a pilot may not continue an approach below decision height unless a visual reference containing a segment of at least 3 consecutive lights being the centre line of the approach lights, or touchdown zone lights, or runway centre line lights or runway edge lights, or a combination of these is attained and can be maintained.

For Category IIIB operations with fail-operational flight control systems using a decision height, a pilot may not continue an approach below decision height, unless a visual reference containing at least one centre line light is attained and can be maintained.

For Category III operations with no decision height there is no requirement for visual contact with the runway prior to touchdown.

Category III RVR Requirements

The lowest minima to be used by an operator for Category III operations are:

Category III minima

	Approach	Decision Height (ft)	Roll-out Control/	RVR (m)
	Category		Guidance System
	IIIA	Less than 100 ft	Not required	200 m
	IIIB	Less than 100 ft	Fail-passive	150 m
	IIIB	Less than 50 ft	Fail-passive	125 m
	IIIB	Less than 50 ft or no DH	Fail-operational	75 m

Figure 5.6: RVR for Cat III approach vs DH & roll-out

Circling

An option will always be available to make an instrument approach to one runway and then carry out a circling manoeuvre to land on another runway more suitably into wind or to meet ATC requirements. This is called Visual Manoeuvring Circling (VM(C)) and is covered in detail in Air Law (010). The instrument approach will terminate at the defined MDH for (VM(C)) and this will be maintained throughout the circling manoeuvre until established on visual final for the landing runway. EU-OPS 1 defines visibility for (VM(C)) as defined in Figure 5.7. These figures are different from the requirements of Annex 6.

All Weather Operations 5

		Aeroplane Category
	A	B	C	D
MDH	400 ft	500 ft	600 ft	700 ft
Minimum Met Visibility	1500 m	1600 m	2400 m	3600 m

Figure 5.7: Visibility & MDH for circling vs aeroplane category

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5		AllWeather Operations

Operations Weather All 5

Visual Approach

A visual approach is defined as an IFR approach completed with visual reference to terrain. There is no requirement for the pilot to see the aerodrome of the landing runway at the commencement of the approach, however, the pilot must be capable of navigating the aeroplane with reference to the underlying terrain. EU-OPS 1 states that an operator is not to conduct visual approaches when the RVR is less than 800 m.

VFR Operating Minima

An operator is to ensure that VFR flights are conducted in accordance with the visual flight rules and in meteorological conditions shown below.

Airspace Class	A B C D E (Note 1)	F G
		Above 900 m (3000 ft)	At and below 900 m
		AMSL or above 300 m	(3000 ft) AMSL or 300 m
		(1000 ft) AGL whichever is	(1000 ft) AGL whichever is
		the higher	the higher
Distance from	1500 m horizontally		Clear of cloud and in sight
cloud	300 m (1000 ft) vertically		of the surface (CCISG)
Flight visibility	8 km at and above 3050 m (10 000 ft) AMSL		5 km (note 3)
	(note 2) 5 km below 3050 m (10 000 ft) AMSL
		Figure 5.8: VMC criteria
Notes:

Note 1: VMC minima for Class A airspace are included for guidance but do not imply acceptance of VFR Flights in Class A airspace

Note 2: When the height of the transition altitude is lower than 3050 m (10 000 ft) AMSL, FL100 should be used in lieu of 10 000 ft.

Note 3: Cat A and B aeroplanes may be operated in flight visibilities down to 3000 m, provided the appropriate ATS Authority permits use of a flight visibility less than 5 km, and the circumstances are such, that the probability of encounters with other traffic is low, and the IAS is 140 kt or less.

Special VFR

Special VFR flights are not to be commenced when the visibility (flight or ground) is less than 3 km and not otherwise conducted when the flight visibility is less than 1.5 km.

Note: The criteria defined in ICAO Annex 6 is slightly different

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AllWeather Operations		5

All Weather Operations 5

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		5			Questions
					Questions
					1.	What is the speed range for a category C aeroplane?
						a.	Up to 90 kt
						b.	91-120 kt
						c.	121-140 kt
						d.	141-165 kt
	5
					2.	What constitutes Low Vis Procedures?
	Questions
						a.	RVR less than 400 m
						b.	Precision approaches
						c.	Low Vis Take-off and Cat II/III approaches
						d.	Low Vis Take-off and precision approaches
					3.	What is the minimum RVR for a Cat D aircraft taking off from an aerodrome with
						full facilities and multiple RVR information?
						a.	200 m
						b.	150 m
						c.	125 m
						d.	400 m
					4.	What is the system minima for an SRA approach terminating at 2 miles?
						a.	250 ft
						b.	300 ft
						c.	350 ft
						d.	400 ft
					5.	Unless otherwise cleared, what is the minimum RVR for a non-precision approach?
						a.	700 m
						b.	750 m
						c.	800 m
						d.	850 m
					6.	What is the system minima for a Cat I approach manually flown by a single pilot?
						a.	200 ft/550 m
						b.	200 ft/800 m
						c.	100 ft/350 m
						d.	100 ft/550 m
					7.	What is the minimum met vis for a cat B aircraft on a circling approach where the
						aerodrome stipulates a minimum circling height of 900 ft?
						a.	1500 m
						b.	1600 m
						c.	2400 m
						d.	3600 m

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Questions 5

8.For VFR flight (in a cat C aircraft) what is the minimum horizontal visibility below 10 000 ft?

a.8 km

b.5 km

c.1500 m

d.300 m

Questions 5

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