An automatic flight coach for student pilots. A small box on the glare shield records the flight. After landing, your phone grades it against the FAA's own training standards.
Learning to fly is expensive, and most of the feedback after a lesson is the instructor's memory of the flight. A student hears “your turns were a bit sloppy” but cannot see which turns, by how much, or whether they are getting better.
Things it records
5
Motion, altitude, heading, GPS position, nearby traffic
ACS altitude standard it grades against
±100ft
FAA Airman Certification Standards
Wires to the airplane
0
Battery powered. Works in any airplane.
Internet needed at the airport
0
The box makes its own Wi-Fi network
1The gap
Newer airplanes can log flight data. The older trainers that flight schools rent out, the ones students can afford to fly, have no such instrumentation. Flight Logger closes that gap with a low-cost box that works in any airplane.
How it works
01 In the cockpit
Press one button and fly. The box records how the airplane moves, its altitude, heading and GPS position, and the other aircraft nearby. It needs nothing from the airplane: no power, no wiring, no modification.
02 After landing
Your phone joins the box's own Wi-Fi, copies the flight and grades it against the FAA's training standards. Did you hold altitude within 100 feet? Were your turns coordinated? Did you level off cleanly? No internet at the airport required.
03 Over time
Flights go to your account when the phone has a connection. Track whether your coordination, altitude control and landings improve across weeks of training. Instructors can follow all of their students.
Fig. 3.1Altitude keeping in cruise, simplified
| Standard | FAA ACS: hold altitude within ±100 ft |
|---|---|
| Measured with | Barometer, set to the local altimeter setting from the airport's weather report |
| In the debrief | Deviation over the flight, and the worst moment on the map |
| Example | ±23 ft, Pass |
Fig. 3.2The turn coordinator: keep the ball centered
| Standard | Coordinated flight: the ball stays centered in every turn |
|---|---|
| Measured with | Side force from the motion sensor |
| In the debrief | Each turn graded. Left turns compared with right turns. |
| Example | 86% of turn time coordinated, Review |
Fig. 3.3Climb to a target altitude and level off
| Standard | Level off at the target altitude, within ±100 ft |
|---|---|
| Measured with | Barometer and motion sensor |
| In the debrief | Each level-off: the overshoot and the time to settle |
Fig. 3.4Left traffic, runway 24. Each circuit is found automatically.
| Found automatically | Each circuit, from takeoff to touchdown |
|---|---|
| In the debrief | Takeoff, pattern altitude, approach and landing for each circuit |
| Context | Nearby airports and their traffic patterns, from FAA data |
Fig. 3.5Aircraft heard by the onboard ADS-B receiver
| Source | Onboard ADS-B receiver, the position broadcasts of other aircraft |
|---|---|
| In the debrief | Who was in the pattern with you, and how close they came |
| Purpose | Debrief context, not a live cockpit traffic display |
I am a student pilot. My debriefs were short, because my instructor had to get to the next student. Stress made me forget parts of the flight. Flight Logger is the debrief I wanted after every lesson.
What it is not
Planning, charts and weather already belong to ForeFlight and Garmin Pilot. Flight Logger works after the flight, not before it.
Traffic is debrief context: who was in the pattern with you. Nothing competes for the pilot's attention in flight.
It is a coaching tool, at a price and setup an individual student or a small flight school can adopt.
Fig. 5.1Store and forward. The phone carries each flight to the cloud.
| Sensors | Motion, pressure altitude, compass, GPS, ADS-B receiver |
|---|---|
| Power | Rechargeable battery |
| Enclosure | Designed around the antennas and sensors. Radio-transparent, heat-resistant plastic for a sunny glare shield. |
| Controls | One recessed button and a status light |
| Next | First custom circuit board, in KiCad |
| Language | C, no RTOS, one cooperative loop |
|---|---|
| Storage | Append-only flight index with CRC-32, safe through power loss |
| Network | Own Wi-Fi access point, HTTP API, Bluetooth LE |
| Robustness | Keeps recording when a sensor fails, and retries it |
| Tests | 63 host tests with address and UB sanitizers |
| Stack | React Native and TypeScript, on iPhone |
|---|---|
| Data | SQLite on the phone, sync engine with an outbox |
| Analysis | On the phone, with no network: phases, turns, level-offs, landings, wind |
| Maps | Flight path, traffic, airports and patterns |
| Tests | 186 unit tests |
| Infrastructure | AWS CDK, defined as code |
|---|---|
| Accounts | Cognito sign-in for each pilot |
| API | API Gateway and Lambda |
| Storage | S3 for flight logs, DynamoDB for the flight list |
| Sync | Each step repeatable, a flight ID never reused |
Roadmap
Bench tested
A breadboard prototype records every sensor and the traffic nearby. The iPhone app copies flights from the box and grades them.
In progress
The first custom circuit board and enclosure. Then the box flies on my own lessons, and each debrief is compared with what my instructor saw.
Planned
The debrief a good instructor would give: a few plain sentences and one thing to focus on next flight. Ask “why was my second landing hard?” Every answer points back to the measured data.
Planned
Trends across weeks of training, a dashboard for instructors, a full replay of nearby traffic, and Apple Watch heart rate to show where workload peaks.