How we know a flight is real — and how we decide what counts.
Shheletar names aircraft, so the method has to be defensible. Every curfew movement goes through two checks before it reaches the record. Here's how each one works.
Is it real?
Did more than one independent source see it? Provisional → Confirmed
Is it exempt?
Does the leg look like a permitted medevac or emergency? Flagged → or counted
Provisional the same night. Confirmed the next morning.
A movement publishes the same night it happens, marked Provisional. The next morning we check it against other sources and either upgrade it to Confirmed or leave it Provisional. A movement's record number never changes.
Tail number, operator, route and the exact minute, live on the record the same night. So far, only we have seen it.
We saw it with our own antenna. We confirm by checking whether someone else's antenna saw it too. Two independent witnesses means Confirmed. Only us means it stays Provisional.
An independent witness was found. The movement carries a green confirmed badge on the public record.
No independent witness yet. It stays flagged and on the record, never dropped, and can still be upgraded later.
Medevac, or violation? We judge the leg, not the aircraft.
Medical evacuations, diversions and emergencies are permitted inside the curfew. We test each flight leg, because the same jet can fly a medical leg one night and a plain charter the next. For every movement we check what each source reported, then run two tests.
What did it squawk tonight?
“Squawk” just means the identifier a plane broadcasts over the radio so ground systems know who it is. The callsign is set per flight, so it's the strongest signal that this leg is medical.
e.g. MEDIC25
Who operates it?
Used only when there's no medical callsign. It's a weaker signal, since operators fly mixed fleets.
attribution from adsbdb, FR24 override
Any signal, from any source, is a match.
If any source, on any sighting, shows a medical signal, we treat the whole leg as medical. Once a leg looks medical it stays that way: a later data update can't un-flag it.
Something looked medical. Marked with a note on the record.
- Still logged and shown in full
- Excluded from the violation count
- Reader can see why it was exempted
No medical signal on the leg. It goes into the tally.
- Aircraft, route, operator and time
- Counts toward the Frequent Offenders board
- Eligible for the printable record
Three rules that keep the record honest.
We flag, we don't filter.
An exempt-looking flight is never hidden. It stays on the public record, just outside the violation tally, with a note explaining why.
The leg, not the aircraft.
A charter jet that occasionally flies medical is exempted only on the leg it squawks a medical callsign. It's never blanket-cleared as “a medevac”.
We're honest about doubt.
Public ADS-B data can't confirm or rule out a real emergency. Where an operator declares an exemption we say so; otherwise we mark it possible and let you judge.
Every source, and what it's for.
We use only public flight data, not noise readings or anonymous reports. Here's what each source contributes, and whether it counts as independent corroboration:
| Source | Role | What it gives the record |
|---|---|---|
| Our receiver | Primary | Detects the aircraft over Seletar in real time. It's the first sighting of every curfew movement. |
| adsb.lol | Coverage | Additional overnight coverage; its next-day archive gives the authoritative route, origin / destination and path. |
| airplanes.live | Coverage | Additional overnight coverage and bearing on the same movement. |
| adsbdb | Lookup | Route and aircraft-owner attribution: who the operator is. |
| FR24 override | Lookup | Operator-name override where attribution needs correcting. |
| OpenSky | Independent | Someone else's antenna; its sighting is the independent witness that confirms a movement. |
We log what flew and when, nothing more. Shheletar reads open ADS-B records; it doesn't measure noise or take complaints. The curfew window is 2200–0700 SGT, a purely time-based quiet period.
Where the data is uncertain, the record says so rather than guessing. That's why we publish the method: you don't have to take our word for any single movement. You can check it yourself.
Now you've seen the method. See the record.
Every movement on the record was run through both checks. Browse the confirmed log of curfew movements at Seletar.