How to get an alert when something unusual is flying

A flight alert is only as useful as the question behind it. "When does my sister's flight land?" needs a different tool from "tell me when a tanker is circling near here" or "tell me when anything unusual happens at Heathrow".

Status alerts: one flight you care about

These follow a single flight by its number: delays, gate changes, departure, a heads-up before landing. Airline apps send them for your own bookings. FlightAware's free Basic account includes five flight alerts, and its paid plans unlimited ones.

Aircraft alerts: a particular aircraft, airline or type

These tell you when something you have chosen is flying:

• Flightradar24. Alerts on a flight number, registration, airline or aircraft type: 10 on its Silver plan, 25 on Gold and 60 on Business, as of October 2026, by push notification in the app or by email from the website.
• Plane Finder. Paid custom alerts on an airline or flight number, aircraft type, registration, squawk code or transponder address, anywhere or within an area you choose.
• Your own receiver. Hobbyists who run a receiver at home use open-source tools such as Planefence with plane-alert-db, an open list of more than 17,000 interesting aircraft, to post an alert to Discord, Mastodon, Telegram or other services when one flies overhead.

They work best when you already know what you are looking for: a registration, a type, a callsign.

Emergency alerts

The Flightradar24 app can notify you when an aircraft squawks 7700 or 7600, and Plane Finder has a built-in emergency alert for 7700. On X, AirNav Radar's Flight Emergency account posts flights squawking 7700 with a link to follow them. See how to track emergency flights.

Event alerts: something unusual, wherever it happens

The hardest question for a flight tracker is "tell me when something unusual happens", because the tracker does not know what unusual is. A hold, a go-around or a diversion is not in any single message an aircraft sends; it is a shape in the track, and someone has to measure it.

That is what FlyScout does. It watches the world's flights around the clock, measures each track against fixed rules, and an alert fires when a flight matches what you asked for. With FlyScout Pro, an alert is a filter, built the same way as the feed's:

• What happened: any kind of unusual flight, or some, from emergency codes and diversions to long holds, go-arounds, circuits, military tankers on station and rare types.
• Where: near you, within a distance from 25 to 500 km; near any place you pick, such as your home airport, so it keeps working while you travel; or by continent or country.
• Which aircraft: wide-bodies, narrow-bodies, regional jets, private jets, cargo airlines, military aircraft, or the giants and rare types.

Suggested alerts, such as emergencies anywhere, military aircraft, unusual flights near me and the giants, are one tap away. Before you save one, FlyScout shows roughly how many a day it would have sent recently, so you can tune it before it fires.

Keeping alerts useful

• Start narrow. "Emergencies anywhere" meant about five a day between 18 September and 16 October 2026, while an alert for one kind of event near a small airport may stay quiet for weeks. Widen it if it is too quiet.
• Watch a place, not just yourself. An alert on your home airport keeps telling you what happens there when you are away.
• Expect a cap. FlyScout sends one notification per flight and at most six an hour; past that, a single quiet notification counts the rest, so a busy day does not flood your phone.