Definition
The deliberate transmission of false signals designed to imitate legitimate ones, causing a receiver — most commonly a GPS or other satellite navigation receiver — to compute and display incorrect position, time, or velocity information.
Plain English
Someone broadcasts fake signals that pretend to be the real ones from satellites, tricking the aircraft's navigation system into showing the wrong location or time without realizing anything is wrong.
Context Anchor
Seen in satellite navigation, signal interference, and flight planning discussions where pilots are warned that onboard position information may be unreliable.
Derivation
From the English word 'spoof,' originally meaning a hoax or parody. In navigation and electronics, it has come to mean a deliberate deception where a fake signal masquerades as a genuine one. Knowing this helps: spoofing is not jamming (blocking signals) — it is impersonating them.
Why Pilots Care
Spoofing can produce large navigation errors, loss of situational awareness, or hazardous flight-path deviations in GPS-reliant operations.
Analogy
Spoofing is like someone putting up a convincing fake road sign that points drivers the wrong way. The sign looks official, but following it leads you off course.
Intuition Check
Do not think of spoofing as simply a weak or missing signal. Spoofing means a false signal is present and looks believable enough to mislead the equipment.
Example Sentence 1
Crews flying near the conflict zone reported GPS spoofing that caused their navigation systems to display positions hundreds of miles from the actual aircraft location.
Example Sentence 2
ATC broadcast a warning that spoofing had been reported near the arrival route.