Reading your own flight log after a scare

First: preserve the evidence

Before anything else, stop using the equipment in ways that can overwrite the record. Logs live on the controller and, depending on the aircraft, partly on the aircraft itself and in the app. All three have limited space and all three eventually roll over.

1. Do not fly again on the same controller until you have copied the filesAnother flight is another set of records competing for the same space.
2. Copy, do not moveKeep the originals untouched. Work on copies.
3. Note the wall-clock time and the placeLogs are timestamped, but your memory of the weather and the surroundings is not stored anywhere.
4. If the aircraft is missing, get the log before you get discouragedThe last recorded position is the single most useful thing you own, and it is in the file.

The channels that actually matter

A log has dozens of columns and most of them are noise for your purposes. These are the ones that explain incidents.

Finding the moment

1. Start at the end and walk backwardsYou know roughly when it went wrong. Find that point, then scroll back until everything looks normal. The interesting part is between those two marks.
2. Look for the first channel that movedNot the loudest one. If satellites fell four seconds before the mode change, the mode change is a consequence, not a cause.
3. Line up the stick inputsWas the aircraft moving because you asked, or on its own? This single comparison answers most "it flew away" questions.
4. Check the two altitudes against each otherA divergence between barometric and GPS altitude around the event narrows the cause quickly.
5. Read the warnings in orderThe sequence of warnings is a narrative. It often names the cause outright.

Patterns worth recognising

What a log cannot tell you

• What the air was doing. Wind is inferred from how hard the aircraft worked, never measured directly.
• What was physically there. A log will not show you the cable, the branch or the bird.
• Why a component failed. It shows the symptom and the moment, not the metallurgy.
• Anything after the recording stopped. The last entry is the last thing you know, and it is often several seconds before the end of the flight.
• Intent. It records what the sticks did, not what you meant.

Using logs when nothing went wrong

The most valuable reading is done on ordinary flights, because that is where you learn what normal looks like for your aircraft. Someone who reviews good flights recognises a bad one immediately.

1. Learn your normal hover currentSo an abnormal one is obvious the first time you see it.
2. Track how battery capacity agesThe same flight profile costing more each month is a pack telling you it is finishing.
3. Compare wind daysSeeing what a 20 km/h day actually cost you turns a forecast into a number you understand.
4. Check your own smoothnessStick traces are honest about how jerky your inputs are, and that is where better footage comes from.

If it becomes a formal matter

If an incident involves other people, property or an authority, the log stops being a curiosity and becomes a record. Treat it accordingly: keep originals unedited, note who has copies, and be careful about publishing an interpretation before you are sure of it. A log read in a hurry has convicted plenty of innocent components, and an early confident wrong answer is hard to walk back.

Where Fly4cast fits

Fly4cast reads DJI flight logs directly, draws the track on a map with a timeline you can scrub, and puts the technical channels beside it. You get the moment and the numbers in one place instead of staring at a spreadsheet — and because your earlier flights are there too, you have something to compare against.