Airfield construction

What's in a name?

• Airfields are areas of land where aircraft take off and land. The word ‘airfield’ only covers the land itself – it doesn’t include any buildings or installations.
• Aerodromes are areas of land (or water) where aircraft take off and land, as well as the buildings and installations that are there.
• Airports are aerodromes that may handle scheduled air traffic. Airports often have customs and other travel facilities.

Features of an airfield

• Runway – The area of the airfield used for take-off and landing. Not every runway has a tarmac surface – grass is often used for gliders and light aircraft.
• Perimeter track – The roadway around the outside of most military (and some civil) airfields. This is sometimes used as an aircraft taxiway.
• Control tower – The air traffic control centre of an airfield. They’re marked by a yellow board on the outside showing a black ‘C’.
• Signal square – A square marked on the ground, usually near the control tower, containing details of operations and facilities at that airfield.
• Hangar – A large ‘shed’ that aircraft are kept in.
• Taxiways – Grass or tarmac routes between operational areas.
• Apron – Outside parking for aircraft when they’re not in use.
• Cable dropping area – The area where a gliding, paragliding, or parascending launching cable will fall to earth after being jettisoned (dropped) by the glider at (or near) the top of its climb. It can be a wide area, it’s not necessarily just over the runway strip.
• Tow rope – A length of nylon rope that a light aircraft or winch uses to tow a glider into the air. The glider’s pilot will either decide to land with the tow rope attached or will jettison (drop) it during a ‘dummy’ approach prior to landing. In either case, the rope can be dangerous as it’s not easily visible and has a heavy metal ring at the free end.

A bit of history and context

When airfields were first built, people thought it was best to have a triangular pattern of runways to reduce the need for landings to be made in a crosswind. As aircraft developed and landing speeds increased, the length of the runway became more important than the wind direction. Modern airfields confine operations to one or two runways, which are 50 metres wide and 1,500 metres long. Where large, heavy aircraft operate, main runways can be as wide as 75 metres, and as long as 3,500 metres.

The approach and overrun areas must be kept free of obstructions in case aircraft go beyond the runway when departing or landing. The runway threshold (the beginning of the runway the aircraft can use for landing) is marked by a broad white line across its full width. White chevrons before to the threshold indicate a sterile area (an area pilots shouldn’t use to touch down). A broken white line’s used to indicate the runway centreline. Two numbers painted at each end show the magnetic direction of the runway to the nearest 10 degrees.

Airfield controllers work from a glass control cabin at the top of the control tower, where they have a clear view of the airfield. Approach controllers work from another part of the tower – they use radio and radar equipment. In some cases, ground controllers work from a caravan that’s to the left of the runway being used. The caravan is painted in red and white checks, and it has the elevation of the airfield above sea level in black figures on its side. A white letter ‘T’ that indicates the landing direction being used is displayed close by.

Accessing an airfield

Before entering any airfield, you must get permission from the appropriate controlling body – it doesn’t matter whether it’s a private, civil, or military airfield. The only exceptions to this are the spectators’ enclosures at civil airports, or open days at military airfields.

When you’re walking to a point on the airfield, you should follow access roads and signs if they’re clearly marked. If they’re not, ask the airfield controller for full directions to your intended destination, as well as information about methods and direction of aircraft launching or taking off. If the airfield controller isn’t available, stick close to the perimeter wherever possible. Do not cross the airfield directly.

Be aware of:

• Aircraft approaching, landing, or taking off – they may do this from any direction.
• Glider launching cables and equipment.
• Glider tugs trailing towing ropes.
• Parachutists or paragliders.

1. Each group should come up with the rules of access for their airfield, starting with how someone would obtain permission from the appropriate controlling body. They should write down their rules clearly.
2. Each group should join with another group.
3. The two groups should take it in turns to use their model to demonstrate how someone would gain access to the airfield, following the rules they created.

1. On or next to their models, each group should draw out a circuit pattern showing the typical path aircraft follow when taking off, flying a circuit, and landing.
2. They should cut out arrows from sticky notes or paper and place them on your runway and around the airfield to clearly show the direction of movement (the circuit).
3. They should assign a runway heading, based on compass directions. For example:
   • If your runway points east–west, label one end as Runway 27 (for 270°) and the opposite end as Runway 09 (for 90°).
   • Mark the runway ends with these numbers.
4. Once finished, Write or discuss how aircraft:
   • Use the circuit to take off, land, and move between runways and parking areas.
   • Follow the pattern to avoid collisions and maintain a safe flow of traffic.
5. Include how Air Traffic Control (ATC) uses the circuit to:
   1. Monitor and direct aircraft.
   2. Keep aircraft safely spaced
   3. Communicate takeoff, landing, and taxi instructions with pilots.
6. Let everyone share their models. 

Things to consider

• Aircraft use runways to take off and land.
• They use taxiways to move between runways and parking areas.
• The runway heading is the direction the runway points, expressed in degrees (to the nearest 10, dropping the final zero).
• Runway headings can change over time due to shifts in magnetic variation.

1. Each group should discuss:
   1. What markings and signals are needed on their airfield.
   2. What do pilots need to see when taking off, landing, or taxiing.
   3. How do lights and pyrotechnic signals help aircraft know where to go, especially at night or in poor visibility.
2. Then, they should add Markings to their Models.
3. They should use sticky notes (or paper), along with pens or pencils, to create the markings, lights, and signals — and then attach them to their model to show where everything would go.
4. Once complete, each group should share their newly labelled model for feedback.

Things to consider

Runway markings

• Runway markings are white.
• Each runway is marked with two white painted numerals to show the runway heading or runway number.
• The centreline is shown with a broken white line.
• Where there’s not enough contrast between the runway and its surroundings, or if the runway is more than 45 metres wide, it is bordered by solid white lines known as side-stripe markings.
• The runway threshold (where landing begins) is marked with long white stripes along the runway.
• If the landing threshold has to be moved further up the runway (due to an obstruction), displacement markings are used: four chevrons and a solid bar.

Taxiway markings

• Taxiway markings are yellow
• The centreline is a broken yellow line.
• Where contrast is poor, the taxiway is bordered by dashed yellow edge markings.
• At the junction with a runway, there’s a holding position line: two yellow lines, one solid and one broken, painted across the taxiway.
• Beside the holding position is a sign showing the runway number in white on a red background.

Light and pyrotechnic signals

Airfields use coloured lights to guide aircraft, especially at night or in poor visibility.

Here’s what the colours mean:

• Runway centrelines – white
• Runway threshold – green
• Obstacles or sterile areas – red
• Taxiway centreline – green
• Taxiway edges – blue (used on sharp or dangerous corners only)
• Runway guard lights – orange (warns of an approaching runway)
• Stop bar – red (aircraft must not cross)

Things to Remember:

• Markings and lights are essential for safety, especially in bad weather or at night.
• Pyrotechnic signals can be used where radio communication isn’t possible.
• Pilots rely on clear markings and signals to know where to stop, where to taxi, and when it's safe to take off or land.