Setting up aircraft alerts: notifications for registrations, types and airlines

The Beluga XL is on its way, the special livery is coming in at midday for once, the rare charter aircraft is flying a traffic pattern – and you only find out in the evening from the forum. That is exactly what notifications for aircraft, types and airlines are for. Instead of opening the live map every ten minutes, you define once what interests you and get a message when the time comes. This guide shows you which kinds of alerts exist, how to set them up in Flightradar24 and FlightAware, what community tools like Plane-Alert do differently and why an alert is sometimes silent even though the aircraft has long been on its way.

The short answer

You set up an aircraft alert by defining a criterion in a tracking service – flight number, registration, aircraft type, airline or airport – and allowing the app to send you notifications. Flightradar24 offers custom alerts in the mobile app and email alerts on the website. FlightAware specializes in alerts for individual flights and aircraft. If you want to filter freely and for free, use your own ADS-B receiver with community software like Plane-Alert.

Three kinds of alerts – and which ones you need as a spotter

Not every alert fits every question. Before you set anything up, it is worth distinguishing the three basic logics.

• Flight alerts are tied to a flight number, such as a specific connection of Lufthansa. They report departure, delay, diversion or landing. Handy for passengers and for spotters who know that a target aircraft is used on a fixed rotation. The weakness: tomorrow a completely different aircraft may fly under the same flight number.
• Aircraft alerts are tied to the registration or the ICAO hex code. They follow a specific aircraft, no matter which flight number it is operating. This is the classic for special liveries, new deliveries or aircraft with test registrations.
• Filter alerts react to a condition: an aircraft type, an airline, a destination or departure airport, a squawk code. With them you catch rarities whose registration you do not even know yet – for example every Antonov An-124 heading to your home airport.

Alert type	Key	Typical use	Limit
Flight alert	Flight number	Scheduled flight with a known rotation	Aircraft can change daily
Aircraft alert	Registration or hex code	Special livery, one-off, new delivery	Set up again after re-registration
Filter alert	Type, airline, airport, squawk	Rare types, guest airlines, emergencies	Often only in paid tiers or with your own hardware
List alert	Curated list of hex codes	Military, government, historic	Only as good as the list is maintained

For most spotters, aircraft and filter alerts are the decisive ones. How to find out the registration of a particular aircraft in the first place is explained in the guide Tracking an aircraft by registration.

Flightradar24: custom alerts in the app

For many, Flightradar24 is the first port of call. It is important to know that the service distinguishes between custom alerts, which exist only in the mobile app, and email alerts, which you manage on the website in the account area under Alerts.

Flightradar24 keeps changing which criteria are available in which tier. Custom alerts require a paid subscription; what Silver, Gold and Business each include and whether the upgrade is worth it for you is covered in Is a Flightradar24 subscription worth it?. Check the provider’s current comparison table before subscribing.

For a single flight you are watching right now, there is also the live feature: as a Live Activity on iOS, as a live notification on Android. You mark the flight with “Follow” and see the progress on the lock screen. According to Flightradar24, it is available in all tiers, including the free account. For the last half hour before landing, this is often more convenient than a classic alert.

And if you share your data with your own receiver, Flightradar24 gives you a free Contributor account as long as your feed is active. How to set up the feeder is shown in Setting up fr24feed.

FlightAware: alerts for flights and aircraft

FlightAware approaches the topic from the traveler’s point of view. Its alerts are designed to inform you about delays, cancellations and upcoming landings of a specific flight. Besides the flight number, you can also track an aircraft by its registration – for spotters, that is the more interesting route.

Here is how to go about it:

1. Search for the flight or registration. Enter the flight number or registration in the search and open the detail page.
2. Create the alert. Using the alert function on the detail page, you choose which events interest you, such as delay, cancellation or landing.
3. Choose the delivery method. Depending on your account and device, the alert arrives by email or as an app push notification.
4. Keep an eye on the quota. The Premium subscriptions explicitly advertise unlimited alerts. So check how many alerts your free account allows.

FlightAware’s strength lies in predictability: if you know a particular aircraft is coming from overseas tomorrow, the alert reliably tells you when it departs and when it is expected to land. The service is less suited to questions like “Which rare types are coming today?” How the two services differ overall is compared in Flightradar24 vs. FlightAware.

Community tools: Plane-Alert and your own receivers

If you run your own ADS-B receiver, a second, free world is available to you. The best-known tool is Plane-Alert, part of the open-source project Planefence by the SDR Enthusiasts.

Planefence runs as a Docker container alongside your feeder, such as readsb, dump1090 or ultrafeeder, and reads the data via the SBS output on port 30003. The Planefence part logs aircraft that pass your station within a set radius and below a certain altitude. Plane-Alert, on the other hand, watches for specific aircraft from a list – no matter where in your reception range they show up.

The default list is called plane-alert-db and is maintained by the community on GitHub. It contains “interesting” aircraft, from government and military aircraft through police, coast guard and ambulance aircraft to historic aircraft and curiosities, each with hex code, registration, operator, type and category. You can add your own lists, for example with the hex codes of the special liveries you are still looking for. Aircraft can be excluded by ICAO type, hex code, registration or free text.

Planefence sends the alerts to Telegram, Discord, Mastodon, BlueSky, RSS or MQTT, among others. With that you can build a private channel or supply a group of friends from your region. How such messenger groups work among spotters is described in Messenger groups for spotters.

The advantage of your own hardware: you see what your antenna sees, unfiltered and without a subscription. The drawback: range is limited, so an alert only comes once the aircraft is already in your region. Building your own ADS-B receiver is recommended as a starting point, and for feeding several networks at once, the guide to Ultrafeeder. If you would rather use other people’s data, the unfiltered networks offer an alternative – more in Community trackers compared.

Which route suits you?

Building good alerts: filters that do not annoy

The biggest mistake with alerts is not a missing one but one that is too broad. If you subscribe to “all Boeing 747s” worldwide, you get so many messages that after two days you ignore all of them. A few rules help:

• Narrow it down geographically. A type alert is only useful once it is tied to your airport – for example to arrivals in Frankfurt or Munich.
• Judge rarity realistically. What is everyday at a hub is a sensation at a regional airport. The article How rare is my sighting? helps with calibrating.
• Registration instead of flight number for one-offs. Special liveries change rotation daily. An overview of where to find them is given in Finding special liveries.
• Hex code as a fallback. After a re-registration the registration changes, and with a change of the country of registry the hex code usually does too. Check both when an aircraft suddenly “disappears.”
• Use emergency alerts deliberately. The 7700 alert is exciting, but no reason to race to the fence. What the codes mean is explained in Squawk 7500, 7600 and 7700.

When the alert stays silent

A missing alert is rarely a fault of the app. Check the causes in this order:

Cause	How to recognize it	What you can do
Missing notification permission	Alert is saved, but nothing ever arrives	Grant permission in the system settings, exempt the app from power saving
No coverage	Aircraft appears only sporadically or as estimated on the map	Use a second source or build your own receiver
Filtered aircraft	Aircraft is missing entirely at the commercial service	Check an unfiltered community tracker
Wrong key	Registration misspelled or outdated	Cross-check registration and hex code
No transponder signal with position	Aircraft sends only Mode S without a position	Hope for MLAT coverage or rely on visual reports

The background on missing aircraft is explained in Why an aircraft does not appear on Flightradar, and the article on MLAT covers Mode S targets without a position. If you want to track military aircraft, you run into these gaps especially often – tips in Tracking military aircraft online.

From alert to photo: the spotter routine

An alert alone does not yet give you a picture. What matters is what you do afterward. A two-step approach has proven itself: an early alert at departure from the origin airport tells you whether the trip is worth it. A second look at the live map shortly before arrival tells you where you need to stand. How reliable the displayed arrival time is is explained in How accurate are ETA predictions?. For the right location you need the current runway direction in use, which depends on the wind – the basics are in Understanding the runway direction in use at airports.

At the Munich Airport visitors’ hill, for example, the runway direction in use decides whether your target aircraft rolls past close to you or lands on the other runway. With the alert behind you, you can plan calmly instead of reacting in a rush. And after landing, the sighting belongs in your logbook – how to complete it afterward with ADS-B data is shown in Matching sightings with ADS-B.

Conclusion

Good aircraft alerts start with the right question: do you want to catch a specific aircraft, a type or a whole category? For one-offs, the registration is the most reliable key, in Flightradar24 through the custom alerts in the app, in FlightAware through the aircraft alerts. For rarities you need filters, which the commercial services mostly offer in paid tiers. It becomes free and unfiltered with your own receiver and Plane-Alert. If you combine two sources and keep your filters narrow, your phone rings less often – but always when it is worth it. You can find an overview of more tools in the flight tracking apps comparison.