Synthetic vision is an aviation display system that gives pilots a computer-generated view of the outside world. It shows terrain, obstacles, runways, horizon lines, and flight guidance even when clouds, darkness, or haze block the real view. This matters because many accidents happen when pilots lose awareness of their position relative to terrain or the runway.
A synthetic vision display acts like a virtual window, helping pilots understand the aircraft's situation quickly.
Key Facts
- Synthetic vision combines aircraft position, attitude, heading, and a terrain database to draw a 3D view.
- Groundspeed formula: v = d/t, where v is speed, d is distance, and t is time.
- Descent angle can be estimated by tan(theta) = altitude loss / horizontal distance.
- A common glide path is about 3 degrees, which gives about 318 ft of descent per nautical mile.
- GPS position, inertial sensors, and air data help the system place the aircraft correctly in the virtual scene.
- Synthetic vision improves situational awareness but does not replace pilot judgment, instrument procedures, or visual requirements.
Vocabulary
- Synthetic Vision System
- A cockpit system that creates a 3D computer image of terrain, runways, and flight guidance using aircraft data and stored databases.
- Primary Flight Display
- The main cockpit screen that shows essential flight information such as attitude, altitude, airspeed, heading, and navigation cues.
- Terrain Database
- A stored digital map of ground elevations, obstacles, airports, and runways used to build the synthetic scene.
- Flight Path Vector
- A symbol on the display that shows where the aircraft is actually moving through the air.
- Situational Awareness
- A pilot's understanding of the aircraft's position, motion, environment, and possible hazards.
Common Mistakes to Avoid
- Treating synthetic vision as a live camera view is wrong because it is a computer drawing based on databases and sensor inputs, not a real-time optical image.
- Ignoring database currency is wrong because outdated terrain, obstacle, or runway data can make the displayed scene incomplete or misleading.
- Assuming the display proves the aircraft is safely clear of terrain is wrong because GPS errors, sensor faults, or database limits can still create risk.
- Confusing the flight path vector with the nose of the aircraft is wrong because the aircraft can point one way while wind and momentum carry it along a different path.
Practice Questions
- 1 An aircraft is 6 nautical miles from the runway threshold and is on a 3 degree glide path. Using 318 ft of descent per nautical mile, what approximate altitude above the runway should it be at?
- 2 A plane travels 24 nautical miles in 8 minutes while approaching an airport. What is its groundspeed in knots?
- 3 A pilot is flying at night in clouds and sees a runway and terrain on the synthetic vision display. Explain why this display improves situational awareness, and explain one reason the pilot must still follow instrument procedures.