The module closes with the aerodrome's exceptions and its safety net: the paint that says a surface must NOT be used, the fire service whose category and stopwatch the exam quizzes by number, the pecking order on the apron, and a supplementary return to two subjects (declared distances and approach lighting) that the syllabus asks once more, from the design side.
Closed and unusable surfaces
A closed marking shall be displayed on a runway or taxiway, or portion of one, that is permanently closed to all aircraft, and should be displayed on a temporarily closed one, except that it may be omitted when the closing is of short duration and adequate warning by air traffic services is provided. The colour follows the surface: WHITE on a runway, YELLOW on a taxiway, each a cross laid on the pavement. On a runway the crosses appear at each closed end and at intervals of not more than 300 m between; on a taxiway, at least at each end of the closed portion. When the closure is permanent, all normal runway and taxiway markings are obliterated, and the lighting is not operated except for maintenance. Where a usable runway or taxiway used at night crosses the closed area, unserviceability lights are placed across the entrance at intervals not exceeding 3 m.
Two more warnings complete the vocabulary. Shoulders of taxiways, turn pads, holding bays and aprons (non-load-bearing surfaces that cannot readily be distinguished from load-bearing ones and could damage an aircraft) have the boundary marked by a taxi side stripe marking: a pair of solid yellow lines, each 15 cm wide and 15 cm apart, the outer edge approximately on the edge of the load-bearing pavement, in the same colour as the taxiway centre line. And when the paved surface before a threshold exceeds 60 m in length and is not suitable for normal use by aircraft, the whole length is marked with a chevron marking pointing in the direction of the runway: a conspicuous colour contrasting with the runway markings, preferably yellow, at least 0.9 m in overall width. Chevrons say: this pavement is not usable by aircraft at all — not for landing, not for take-off, not for taxiing.
Rescue and firefighting
The principal objective of a rescue and firefighting service is to save lives in the event of an aircraft accident or incident occurring at, or in the immediate vicinity of, an aerodrome: creating and maintaining survivable conditions, providing egress routes, and rescuing occupants who cannot escape unaided. Everything else about the service (vehicles, agents, the category itself) serves that sentence.
The aerodrome category for RFF is determined from the overall LENGTH of the longest aeroplanes normally using the aerodrome, and their FUSELAGE WIDTH: evaluate the length first, and if that aeroplane's fuselage width exceeds the maximum for the length-derived category, the category becomes one higher. One relief valve exists: where the aeroplanes of the highest category make fewer than 700 movements in the busiest consecutive three months, the protection provided may be one category below the determined one, a take-off or a landing each counting as a movement.
The stopwatch is the most examinable number in the section. Response time is the time between the initial call to the rescue and firefighting service and the time when the first responding vehicle is in position to apply foam at a rate of at least 50 per cent of the specified discharge rate. The operational objective: a response time not exceeding THREE minutes to any point of each operational runway (with a recommendation to achieve TWO minutes), and, likewise as a recommendation, not exceeding three minutes to any other part of the movement area, all in optimum visibility and surface conditions: daytime, good visibility, no precipitation, the response route uncontaminated.
The apron: right of way and refuelling fires
Where traffic warrants it, an apron management service regulates movement on the apron, coordinates entry and exit with the tower, and keeps vehicles orderly. Its pecking order is a learning objective: an emergency vehicle responding to an emergency has priority over ALL other surface movement traffic, and a vehicle operating on an apron shall give way to an emergency vehicle and to an aircraft taxiing, about to taxi, or being pushed or towed; other vehicles sort themselves by local regulations. Against a vehicle, the aircraft always wins; against the fire truck, nobody does.
During the ground-servicing of an aircraft, fire extinguishing equipment suitable for at least initial intervention in a fuel fire, and personnel trained in its use, shall be readily available, along with a means of quickly summoning the rescue and firefighting service in the event of a fire or major fuel spill. And when refuelling takes place while passengers are embarking, on board or disembarking, ground equipment is positioned to keep a sufficient number of exits usable for expeditious evacuation, and a ready escape route from each of those exits: the airbridge and the steps stay where the slides and doors need them.
Declared distances, from the design side
The syllabus returns to the four declared distances: take-off run available (TORA), take-off distance available (TODA), accelerate-stop distance available (ASDA) and landing distance available (LDA). It asks when they collapse into one number: all four equal the runway length when the runway has no clearway and no stopway, and the threshold is located at the extremity of the runway. Each departure from that plain runway moves exactly one distance: a clearway increases TODA by its length; a stopway increases ASDA by its length; and a displaced threshold reduces the LDA for approaches made to that threshold, leaving the take-off distances untouched.
Approach lighting: groups, versions and the threshold
The supplementary material sorts approach lighting into two main groups: simple approach lighting systems, and precision approach lighting systems (categories I, II and III). The simple system (the 420 m centre line with its crossbar at 300 m) comes in two versions, by the form of each centre line light: a single light source, or a barrette at least 3 m long; where 420 m of centre line cannot physically be provided, it is extended to 300 m so as to include the crossbar, or as far as practicable with every light a barrette.
The category I system (900 m of centre line, crossbar at 300 m, fixed lights showing variable white) likewise has two basic versions. In the distance-coded version, each centre line position carries a single source in the innermost 300 m, two sources in the central 300 m and three in the outer 300 m (the pilot literally counts distance), with additional crossbars at 150, 450, 600 and 750 m. In the barrette version, each position is a barrette at least 4 m long, each usually supplemented by a sequenced flashing light, flashing twice a second from the outermost light inward to the threshold: the "rabbit" running home. For category II and III, the inner 300 m is the picture the previous lesson drew: white centre-line barrettes flanked by two rows of red side barrettes, with crossbars at 150 m and 300 m.
Finally, the arrangement and the threshold are one geometry: every approach lighting system is measured FROM THE THRESHOLD, the crossbar at 300 m from it, the centre line running 420 or 900 m out from it. Displace the threshold, and the whole system displaces with it: the approach lights then stand over the runway portion before the threshold (the portion whose centre line now wears white arrows pointing to the displaced threshold), so the runway stays fully lit for the approach while the arrows deny that surface to landings.