Questions and answers

What is Akashlipi?

Akashlipi is a Linux app that keeps a running log of every aircraft an RTL-SDR radio dongle receives over ADS-B. Each pass is written down with the aircraft’s registration and type, its owner and operator, the airline and flight number, the route, the weather at both ends, winds and autopilot data, and a fuel and CO₂ estimate. It has its own app window with a live radar, and a second dongle adds aircraft text messages (ACARS and VDL2) decoded into plain English.

What does the name mean?

आकाशलिपि (Akashlipi) joins two Sanskrit-derived words: आकाश (ākāśa), the sky, and लिपि (lipi), a script or way of writing. It writes down what crosses your sky. The app was previously called ADS-B Logger and, before that, SkyLogger. Its package and command are still named adsb-logger.

What hardware do I need?

A Linux computer (a 64-bit PC, laptop or Raspberry Pi with a 64-bit OS), an RTL-SDR USB dongle and an antenna for 1090 MHz. For aircraft messages you need a second dongle and a VHF dipole of about 110 cm. The RTL-SDR Blog V4 driver comes with Akashlipi.

Which download should I pick?

The .deb if your Linux installs software with apt (Debian, Ubuntu, Mint, Raspberry Pi OS, Kali), the .rpm if it uses dnf or zypper (Fedora, RHEL, AlmaLinux, Rocky, openSUSE), and the AppImage for anything else. Take amd64/x86_64 for a PC and arm64/aarch64 for a Raspberry Pi or other ARM board. The download page has all of them.

Does it work on a Raspberry Pi?

Yes, with a 64-bit operating system such as Raspberry Pi OS (64-bit): use the arm64 .deb. There is no build for 32-bit (armhf) systems. On a Pi without a screen, adsb-logger start runs it without the app window.

Does it run on Windows or macOS?

No. Akashlipi is for Linux only.

Does it work outside India?

Yes. ADS-B is the same everywhere, and the aircraft database, route data and weather are worldwide. The owner, lessor and charter-operator details come from India’s DGCA register, so they are filled in for Indian (VT-) aircraft only.

Does it need an internet connection?

Not for receiving and logging. The aircraft database, routes, airports, the DGCA register and cached map tiles are kept on your computer. It goes online only to fill gaps: adsbdb.com and hexdb.io for unknown aircraft or routes, aviationweather.gov for weather reports, OpenSky when you ask for an aircraft’s history, and OpenStreetMap for map tiles not yet cached.

Is anything I receive shared?

Not unless you turn it on. Your log stays in ~/adsb-log on your computer. Sharing aircraft messages with airframes.io and taking part in MLAT are both off by default.

Can I use it alongside SDR++ or other radio software?

Yes, but only one program can use a dongle at a time. Run adsb-logger stop --release-dongle to free the dongles, and adsb-logger start to take them back.

I already run readsb. Will it conflict?

No. If you have your own readsb installed, Akashlipi uses it instead of the one it brings.

What are aircraft messages?

Short texts that aircraft send to their airline and to air traffic control over VHF, using ACARS and VDL2: position reports, gate times, weather requests, clearances, maintenance reports and free text. Akashlipi decodes them into plain English, keeps the original text one click away, and links each message to the aircraft’s logged pass.

How do I check the download is genuine?

Each release includes a SHA256SUMS file. Put it next to the package and run sha256sum --check --ignore-missing SHA256SUMS; it should print the file name followed by OK.

Where is my log, and is it kept when I upgrade or uninstall?

In ~/adsb-log, mainly flights.db and flights.csv, with messages in messages.jsonl. Upgrades keep it and back it up first, and uninstalling never removes it.

Something isn’t working. Where do I start?

Run adsb-logger doctor, or open Manage › Health in the app and use the Fix buttons. The setup guide lists the common problems.