Private Pilot | Lesson 4 - Airports and Air Traffic Control

TABLE OF CONTENTS:
4.1 RUNWAY MARKINGS
4.2 BEACONS AND TAXIWAY LIGHTS
4.3 VISUAL APPROACH SLOPE INDICATORS (VASI)
4.4 AIRPORT TRAFFIC PATTERNS
4.5 WAKE TURBULENCE
4.6 COLLISION AVOIDANCE
4.7 LAND AND HOLD SHORT OPERATIONS (LAHSO)
4.8 ATIS (AUTOMATED TERMINAL INFORMATION SERVICE)
4.9 GROUND CONTROL
4.10 ATC LIGHT SIGNALS
4.11 RADIO PHRASEOLOGY
4.12 ATC TRAFFIC ADVISORIES
4.13 TERMINAL RADAR PROGRAM

4.1 Runway Markings

Most runways have large white runway numbers painted at the beginning of the runway. Runway numbers indicate the magnetic alignment of the runway in use. Runway numbers are rounded to nearest 10° and divided by 10.

Example:
Runway 26 would be aligned with 260° magnetic, approximately.
Runway 9 would be approximately aligned with 090° magnetic

The runway begins at the Runway Threshold. Some runways have thresholds that are displaced and begin some distance from the actual physical beginning of the runway pavement.

A displaced threshold is marked as a broad solid white line across the runway. This broad solid white line indicates the beginning of the full strength runway pavement.
The remainder of the runway, which follows the displaced threshold, is the portion of the runway that may be used for taxi, takeoff and both phases of landing (touchdown and rollout). The paved area before the displaced threshold, which is marked by white arrows is available for taxiing, the takeoff roll, and the landing rollout - basically, any type of aircraft movement other than the touchdown phase of a landing. (see right half of image below)

The paved area before the displaced threshold, which is marked by chevrons (see left half of image above), is UNUSABLE for landing, takeoff, and taxiing - chevrons indicate blast pad and stopway areas for jet blast protection, and emergency stopping only.

Chevrons mark the portions of pavement extending beyond the usable runway that appears usable, but, due to the nature of its structure, is unusable runway. These areas are not available for any normal use, not even taxiing - these areas are for emergency over-runs only.

Closed runways are marked by an "X" on each runway end that is closed.

4.2 Beacons and Taxiway Lights

Most civilian airports with paved runways and weather reporting capabilities have airport beacons. Civilian airport beacons rotate with alternating green and white flashes. These large rotating lights help to identify that location as an airport, as well as give pilots an indication of the current weather conditions at the airport.

During the day, the airport's rotating beacon is usually not in operation. However, operation of the green and white rotating beacon at an airport located in Class D airspace during the day indicates that the weather is not VFR (the visibility is less than 3 SM, or the ceiling is less than 1,000 ft.).

Heliports are identified by a green, yellow, and white rotating beacon.

Military airports and airfields are identified by beacons with two white flashes between each green flash.

Airport taxiways are lighted with blue edge lights.

Also, some airports are equipped with Pilot-Controlled Lighting (PCL).
Pilot-Controlled Lighting is operated through a specific series of clicks of the microphone.

4.3 Visual Approach Slope Indicators (VASI)

Visual Approach Slope Indicators (VASI) consist of system of lights to that provide visual descent angle information during a landing. One important limitation of a VASI is that it only provides glide path information - it DOES NOT provide any runway alignment information.

According to FAR 91.129,
"...each pilot of an airplane approaching to land on a runway served by a visual approach slope indicator shall maintain an altitude at or above the glide slope until a lower altitude is necessary for landing."
Essentially, this regulation ensures that approaches are made with safe descent angles, thus ensuring adequate obstacle clearance.

Additionally, approaches and landings at night should be made in the same way as they are made during daylight, using the same airspeeds, altitudes, and descent angles. The lack of light can play many illusions on a pilot, and make him/her think that they are higher/lower, faster/slower, than they really are.

2-Bar VASI

The most common VASI is the 2-bar VASI, which consists of two rows of tiered lights.

On a 2-bar VASI the lights are based on the glide path for the particular runway, and change colors from red to white depending on your descent angle.

• If you fall below glide path, both light bars appear red ("red over red, means you're dead").
• If you remain on the optimum glide path, the far bar (top, visually) of lights will appear red and the near bar (bottom, visually) of lights will appear white ("red over white, means you're alright").
• If you are above the glide path, both light bars will appear white.

  

Tri-Color VASI

Another type of VASI is the Tri-Color VASI, a single light unit projecting three colors.

• The below glide path indicator is a red light.
• The above glide path indicator is an amber light.
• The on glide path indicator is a green light.

  

Precision Approach Path Indicator (PAPI)

Another type of VASI is the Precision Approach Path Indicator (PAPI).

• Low is four red lights (less than 2.5°).
• Slightly low is one white and three reds (2.8°).
• On glide path is two whites and two reds (3.0°).
• Slightly high is three whites and one red (3.2°).
• High is four whites (more than 3.5°).
  

Pulsating Approach Slope Indicator

Finally, the last type of VASI is the Pulsating Approach Slope Indicator (it's basically a VASI with flashing/pulsating signals) .

• Low is a pulsating red.
• On glide path is a steady white or alternating red/white (depending on model).
• High is a pulsating white.

  

4.4 Airport Traffic Patterns

To assure that air traffic flows into and out of an airport in an orderly manner, an airport traffic pattern is established. The pattern is appropriate to the local conditions, including the direction and placement of the pattern, the altitude to be flown, and the procedures for entering and leaving the pattern.

The segmented circle system provides traffic pattern information at airports without operating control towers. If there is no segmented circle installed at the airport, traffic pattern indicators may be installed on or near the end of the runway.
The segmented circle system consists of:

• The Segmented Circle – located in a position affording maximum visibility to pilots in the air and on the ground, and providing a centralized point for the other elements of the system;
• Landing strip indicators – showing the alignment of landing runways (legs sticking out of the segmented circle); and
• Traffic pattern indicators – indicators at right angles to the landing strip indicator showing the direction of turn from base to final.

Example:
Runways 09 and 36 above use left traffic, while runways 18 and 27 use right traffic.

Wind direction indicator – a wind cone, wind sock, or wind tee installed near the runways to indicate wind direction.

• The large end of the wind cone/wind sock points into the wind. Land as if you were flying out of the large (open) end of the wind cone.
• The cross bar of the wind tee points into the wind. Land toward the cross-bar end of a wind "T" (visualize the "T" as an airplane with no nose, with the top of the "T" being the wings).

Landing direction indicator – a tetrahedron on a swivel installed when conditions at the airport warrant its use. It is used to indicate the direction of takeoffs and landings. It should be located at the center of a segmented circle and may be lighted for night operations.

• The pointed end points toward the direction in which a takeoff or landing should be made; so, plan to land in the same direction that the tip of the tetrahedron is pointing.

However, not all airports have segmented circles, or even traffic pattern indicators. If you approach an airport without an operating control tower, you must make all turns to the left when landing unless visual displays indicate otherwise. Plus, you must comply with any FAA traffic pattern for that airport when departing.

4.5 Wake Turbulence

All aircraft generate "wake turbulence" or "wingtip vortices" while in flight. This disturbance is caused by a pair of counter-rotating vortices trailing from the wingtips. The vortices from larger aircraft can pose problems to those aircraft that fly through them. There have been instances of smaller aircraft being "tossed around" by the wake of larger aircraft.

Two key concepts to remember:

1. Wingtip vortices (wake turbulence) are only created when airplanes develop lift.
2. The greatest vortex strength occurs when the generating aircraft is heavy, clean, and slow.

Wingtip vortex turbulence tends to sink into the flight path of airplanes operating below the airplane generating the turbulence.
So, to avoid this turbulence, you should attempt to fly above the flight path of a large jet rather than below it. And, you should also fly upwind rather than downwind of the flight path, since the vortices will drift with the wind.

With regard to wake turbulence avoidance while taking off and landing, wind plays a critical part. The most dangerous wind, when taking off or landing behind a heavy aircraft, is the light quartering tailwind. It will push the vortices into your touchdown or takeoff zone, even if you are executing proper procedures. You must maintain extra alertness when operating light aircraft around larger, heavier aircraft.

4.6 Collision Avoidance

Most training aircraft are equipped with navigation lights to aid in collision avoidance. Navigation lights on the aircraft consist of a red light on the left wing, a green light on the right wing, and a white light on the tail. (Note: the navigation lights on the wings cannot be seen when looking at the tail of the aircraft.) These colors and positions are standardized across all aircraft, so that pilots can determine which side of the aircraft they are looking at when they observe an aircraft's light.

• In night flight, When an airplane is crossing in front of you from your right to left, you will observe a red light - you will be looking at the left side of the aircraft.
• When an airplane is crossing in front of you from your left to right, you will observe a green light - you willing be looking at the right side of the aircraft.
• When an airplane is flying away from you, you will observe a steady white light - remember, the navigation lights on the wings cannot be seen from the rear.
• When an airplane is approaching you head-on, you will observe a red and green light but no white light.

  A flashing red light on an aircraft is a rotating beacon and may be seen from any angle.

Prior to each maneuver, a pilot should quickly scan the entire area for collision avoidance.

Also, it is a good practice when climbing or descending VFR on an airway that you execute gentle banks left and right to aid in scanning for other aircraft.

All pilots are responsible for collision avoidance when operating in an alert area.

4.7 Land and Hold Short Operations (LAHSO)

In an effort to safely increase airport operations and improve the flow of traffic through an airport, Land And Hold Short Operations (LAHSO) take place at some airports with an operating control tower. LAHSO operations should only be conducted when the visibility is at least good enough for basic VFR weather conditions (3 SM visibility and the ceilings are at least 1,000 ft. Basic VFR is needed to allow pilots visual contact with other aircraft and ground landmarks.

Basically, LAHSO requires that you land and hold short of an intersecting runway or taxiway, or some other designated point on the runway. However, as the pilot in command, you must feel that you can safely accomplish the Land and Hold Short. Therefore, before accepting a clearance to land and hold short, you must determine that you can safely land and stop within the available landing distance (ALD). ATC will provide ALD data upon your request. Also, if your flight planning takes you to an airport that you know conducts LAHSO, ALD data are published in the special notices section of the Airport/Facilities Directory (A/FD).

• Student pilots should not participate in LAHSO operations.
• The pilot in command has the final authority to accept or decline any land and hold short (LAHSO) clearance.
• You are expected to decline a LAHSO clearance if you determine it will compromise safety.
• You should receive a LAHSO clearance only when there is a minimum ceiling of 1,000 ft. and visibility of 3 SM.

4.8 ATIS (Automated Terminal Information Service)

Most "busy" (you should think of these as airports with air traffic control towers) transmit a continuous broadcast of recorded non-control information called "ATIS" (Automatic Terminal Information Service). The information is essential but it is also very routine.

ATIS information usually includes the latest weather, information on active runways, and other pertinent airport remarks. Ceilings are usually not broadcast if they are above 5,000 ft., and visibility is usually not mentioned if it is more than 5 SM.

4.9 Ground Control

Ground Control is the part of air traffic control that controls aircraft movement around the airport while the aircraft are still on the ground. You contact ground control initially after you've started up, gone through any checklists you may have, and are ready to taxi. After telling them who you are, where you are, and where you want to go, ground control will issue a clearance to taxi.

A clearance to taxi to the active runway is a clearance to taxi via taxiways and across intersecting runways, but not onto the active runway.

Remember:
When cleared to a runway, you are cleared to that runway's run-up area, but not onto the active runway itself.
"Taxi into position and hold" is the instruction to taxi onto the active runway and prepare for takeoff, but not to take off.

After landing, you should contact ground control only when so instructed by the tower.

When departing VFR from controlled airports, you should request radar traffic information from ground control on initial contact.

4.10 ATC Light Signals

In the absence of radio communications (your radio suddenly stops working, or, your airplane doesn't have a radio) the tower can communicate with you by light signals. Light signal meanings have different meanings depending on whether you are on the ground or in the air.

Light Signal On the Ground In the Air

Steady Green Cleared for takeoff Cleared to land

Flashing Green Cleared to taxi Return for landing
(to be followed by steady green at proper time)

Steady Red Stop Give way to other aircraft and continue circling

Flashing Red Taxi clear of landing area (runway) in use Airport unsafe – Do not land

Flashing White Return to starting point on airport Not applicable

Alternating Red and Green General warning signal – Exercise extreme caution General warning signal – Exercise extreme caution

You should acknowledge light signals while in the air by rocking your wings in daylight and blinking your lights at night.

If your radio fails and you wish to land at a tower-controlled airport, you should remain outside or above the airport's traffic pattern until you can determine the direction and flow of traffic, then you should join the traffic pattern, maintain visual contact with the tower, and expect to receive light signals.

4.11 Radio Phraseology

It is important to use proper radio phraseology when communicating with air traffic control. When making your initial contact with air traffic control you should start your aircraft call sign with the make or model aircraft and you should state the entire aircraft registration number individually (for example, "Cessna Eight-Two-Four-Nine-Foxtrot" or "Mooney One-Seven-Six-Juliet-Whiskey").

In fact, it is a good practice to continue to state the aircraft type and entire registration number until the air traffic control responds with a shortened version - then you may use the short version (for example, "Four-Nine-Fox" or "Six-Juliet-Whiskey").

When calling out altitudes, state the separate digits of the thousands, and then hundreds, if appropriate (for example, 2,500 ft. = "two thousand, five hundred"). Also, altitudes are MSL, unless you are advised otherwise.

When contacting a flight service station the proper call sign is the name of the FSS followed by "radio" (for example, "Peoria Radio").
When contacting an En Route Flight Advisory Service (EFAS) the proper call sign is the name of the Air Route Traffic Control Center facility serving your area followed by "flight watch" (for example, "Denver Flight Watch").

4.12 ATC Traffic Advisories

ATC radar traffic information services provide pilots with traffic advisories of nearby aircraft. These traffic advisories provide information based on the position of other aircraft from you in terms of clock direction in a no-wind condition (controllers use your ground track, not your heading, to make the advisories).

• 12 o’clock is straight ahead.
• 3 o’clock is directly off your right wing.
• 6 o’clock is directly behind you.
• 9 o’clock is directly off your left wing,
• Other positions are described accordingly, e.g., 2 o’clock, 10 o’clock.

Traffic advisories also usually include:

• The distance away from you that the other aircraft is, in miles.
• The direction of flight of the other aircraft.
• And, the altitude of the other aircraft.

4.13 Terminal Radar Program

Terminal Radar Programs are broken into 4 classes, for VFR aircraft:

1. Basic
2. TRSA (Terminal Radar Service Area)
3. Class C, and
4. Class B

Basic radar service provides safety alerts, traffic advisories, and limited aircraft vectoring (on a workload-permitting basis).

TRSA radar service provides sequencing and separation for all participating VFR aircraft operating withing the Terminal Radar Service Area.

Lesson 4 - Airports and Air Traffic Control eFlash Cards

Lesson 4 - Airports and Air Traffic Control Study Quiz