If you build anything that touches drones (a flight logger, a mapping pipeline, a fleet dashboard, a hobby receiver on an ESP32), you'll run into Remote ID. It's the FAA rule that makes most drones broadcast who and where they are, and it's also one of the topics on the FAA Part 107 Remote Pilot knowledge test.
Here's a developer-friendly breakdown of both: the data, and the exam angle.
What Remote ID is, in one paragraph
Remote ID is 14 CFR Part 89. Since the compliance date (September 16, 2023, with FAA enforcement discretion that ended March 16, 2024), drones that are required to be registered must broadcast identification and location data while they fly, unless they're flown inside an FAA-Recognized Identification Area (FRIA). It's a local broadcast, not a network service: there's no cloud API you can query for every drone in the country.
The three ways to comply
- Standard Remote ID drone. Remote ID is built in by the manufacturer. Broadcasts from takeoff to shutdown.
- Broadcast module. An add-on for drones without built-in Remote ID. Rule of thumb from the test: with a module, the person manipulating the controls must be able to see the drone throughout the flight (visual line of sight).
- FRIA. A defined area (usually requested by community-based organizations or educational institutions) where drones without Remote ID can fly. Both the drone and the pilot stay inside it, with visual line of sight.
What's in the message
This is the part developers usually care about. A standard Remote ID broadcast includes (14 CFR 89.305):
- UA identification: the serial number, or a session ID
- Latitude, longitude, and geometric altitude of the drone
- Latitude, longitude, and geometric altitude of the control station (the pilot)
- Velocity of the drone
- A time mark
- Emergency status
A broadcast module sends a slightly different set (14 CFR 89.315): the module's serial number, the drone's position, altitude and velocity, a time mark, and the takeoff location instead of the live control station location.
That difference is a classic exam trap: standard RID tells observers where the pilot is; a module tells them where the drone took off.
How it's carried
The FAA accepted the ASTM F3411 standard as a means of compliance, and the open-source ecosystem around it is called OpenDroneID. Messages go out over Bluetooth (legacy advertising and long range) and Wi-Fi (Beacon / NAN), so a normal phone can receive them. If you want to play, the OpenDroneID project publishes receiver code for Android, and there are ESP32 transmitter and receiver projects for test benches. (Transmit only on your own bench or in compliance with FCC rules, and never spoof real IDs.)
What the Part 107 test asks
The knowledge test isn't a protocol exam. The Remote ID questions are about rules and judgment, for example:
- A Part 107 drone weighing under 0.55 lb still has to be registered, and registered drones need Remote ID (or a FRIA). The "it's light, so I'm exempt" idea only applies to some recreational flying.
- With a broadcast module, you must keep visual line of sight.
- In a FRIA without Remote ID equipment, both drone and pilot stay inside the FRIA.
- A camera feed doesn't count as visual line of sight (14 CFR 107.31).
The test is 60 multiple-choice questions in 2 hours at a PSI testing center, and you need 70% to pass. Remote ID is a small slice. The big point-losers are usually sectional charts and METAR/TAF weather codes. One recent change worth knowing: since October 26, 2026, some chart questions use images from current sectional charts that aren't in the printed testing supplement, so practice on a current FAA sectional.
Free resources
- FAA: Remote Identification of Drones (faa.gov/uas/getting_started/remote_id)
- eCFR: 14 CFR Part 89 and Part 107
- FAA Remote Pilot Study Guide (FAA-G-8082-22) and the Remote Pilot ACS
- OpenDroneID on GitHub
Disclosure: I run Astra Pilot Academy, which makes Part 107 study materials. If you're actually taking the test, I put 25 of the most-missed questions (Remote ID traps included) into a $1 PDF, and everything we make is in one $19 kit. The free FAA materials above are enough if you practice. Not affiliated with the FAA. Always check the current eCFR before you fly.
