skylight.

UAL2649 United

Airbus A319 131 · N831UA · SFO → ?

· 2:09Quality 77lost lockside-onturned left 49°

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −73%). Download

Trace

Where the aircraft sat in the frame, second by second. Click the chart to jump the video there.

—FOV —az —el —pose —
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
90%
First lockfrom target selected
5.6 s
Centring, medianaz / el while locked
0.11° / 0.12°
Centring, 90th pctaz / el while locked
0.39° / 0.32°
Tightest field of viewhorizontal
3.4°
Time to 8°from first lock
4.6 s
Time to tightestfrom first lock
79.2 s
Time at telefield of view ≤ 5.5°
115.4 s
Jitter at teleaz / el, standard deviation
0.20° / 0.15°
Swing at teleaz / el, peak to peak
1.16° / 1.02°
Pan reversalsper 10 s at tele
0.1
Largest pan hopin any 1 s at tele
7.96°
Largest tilt hopin any 1 s at tele
1.73°
Pose error, mediancommand vs camera
0.57°
Largest correctionvision vs prediction
2.34°
Zoom steps
17

Aircraft & route

Flight
UAL2649
Registration
N831UA
Type
Airbus A319 131
Airline
United
From
SFO
To
—
Ground speed
251 kt
Altitude at closest
6,475 ft
Vertical rate
+1,920 ft/min
Category
A3
ICAO hex
ab5dd4

Pass geometry

Max elevation
30.3°
Elevation at start → end
18.5° → 12.7°
Azimuth at start → end
334° NNW → 201° SSW
Closest-approach azimuth
266° W
Minimum slant range
3.9 km
Heading at closest
185° S
Aspect at closest
side-on (80°)
Turn
turned left 49°
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
2:09 (129.1 s)
Lock
90%

Build & tuning

The tracker build that flew this pass and the live settings that mattered, so passes can be compared across changes.

Build
2026-10-16a — main b067f99 (review cleanup)
Commit
b067f99
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
63.2 MB · 128.1 s · offset -1.2 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
-0.03
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