UAL871 United
Boeing 777 300ER · N2140U · SFO → TPE
· 0:59Quality 82nose/tail
Software-steadied: the hops of the camera motor are smoothed out (plane wobble −75%). Download
Trace
Where the aircraft sat in the frame, second by second. Click the chart to jump the video there.
—FOV —az —el —pose —
Loading telemetry…
Lock
Events
Tracking metrics
How well the camera kept the aircraft centred. Tap a metric for what it means and what good looks like.
- Lockshare of the pass
- 59%
- First lockfrom target selected
- 19.8 s
- Centring, medianaz / el while locked
- 0.35° / 0.32°
- Centring, 90th pctaz / el while locked
- 3.23° / 3.08°
- Tightest field of viewhorizontal
- 5.6°
- Time to 8°from first lock
- 30.8 s
- Time to tightestfrom first lock
- 38.7 s
- Time at telefield of view ≤ 5.5°
- 0.0 s
- Jitter at teleaz / el, standard deviation
- —
- Swing at teleaz / el, peak to peak
- —
- Pan reversalsper 10 s at tele
- —
- Largest pan hopin any 1 s at tele
- —
- Largest tilt hopin any 1 s at tele
- —
- Pose error, mediancommand vs camera
- 0.80°
- Largest correctionvision vs prediction
- 6.30°
- Zoom steps
- 40
Aircraft & route
- Flight
- UAL871
- Registration
- N2140U
- Type
- Boeing 777 300ER (B77W)
- Airline
- United
- From
- SFO · San Francisco
- To
- TPE · Taipei
- Ground speed
- 204 kt
- Altitude at closest
- 1,050 ft
- Vertical rate
- +2,112 ft/min
- Category
- A5
- ICAO hex
- a1cac9
Pass geometry
- Max elevation
- 82.6°
- Elevation at start → end
- 0.1° → 11.9°
- Azimuth at start → end
- 116° ESE → 298° WNW
- Closest-approach azimuth
- 19° NNE
- Minimum slant range
- 354 m
- Heading at closest
- 297° WNW
- Aspect at closest
- nose/tail (5°)
- Turn
- straight (0°)
- Departure
- Yes — climbing out after take-off
- Zenith pass
- No
- Dead-zone wrap
- No
- Duration
- 0:59 (58.6 s)
- Lock
- 59%
Build & tuning
The tracker build that flew this pass and the live settings that mattered, so passes can be compared across changes.
- Build
- 2026-10-16e — A/B mountPrior + candidate diagnostics
- Commit
- ffe4b92
- Node
- v22.22.2
- Camera
- TONGVEO 20x PTZ · 1920×1080 @ 30 fps
- Clip
- 29.0 MB · 58.0 s · offset -1.1 s
- pursuit
- velocity
- maxLeadSec
- 3
- panLatencySec
- 0.6
- tiltLatencySec
- 0.4
- rippleDeg
- 0.5
- rippleTeleDeg
- 0.25
- maxSpeedStepFwps
- 0.45
- speedReachFrac
- 0.8
- lockedSigmaDeg
- 0.35
- sigmaGrowthDps
- 0.1
- aimLeadSec
- -0.1
- correctionSlewDps
- 2.5
- kp
- 1
- ki
- 0.6
This clip and poster are © Skylight (Cameron Paczek): free for non-commercial use with credit to skylightceiling.com, not MIT. License