skylight.

UAL44 United

Boeing 787-9 · N81105 · SFO → ZRH

· 0:38Quality 68side-on

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −69%). 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
80%
First lockfrom target selected
5.1 s
Centring, medianaz / el while locked
0.73° / 1.83°
Centring, 90th pctaz / el while locked
6.94° / 6.21°
Tightest field of viewhorizontal
6.6°
Time to 8°from first lock
31.8 s
Time to tightestfrom first lock
32.1 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
4.96°
Largest correctionvision vs prediction
1.34°
Zoom steps
35

Aircraft & route

Flight
UAL44
Registration
N81105
Type
Boeing 787-9
Airline
United
From
SFO · San Francisco
To
ZRH · Zurich
Ground speed
179 kt
Altitude at closest
1,200 ft
Vertical rate
—
Category
A5
ICAO hex
ab0f89

Pass geometry

Max elevation
73.1°
Elevation at start → end
15.0° → 13.3°
Azimuth at start → end
111° ESE → 299° WNW
Closest-approach azimuth
17° NNE
Minimum slant range
371 m
Heading at closest
298° WNW
Aspect at closest
side-on (79°)
Turn
straight (0°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
0:38 (38.2 s)
Lock
80%

Build & tuning

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

Build
2026-10-14n — vision skyline mask 31x cheaper (loop back to ~15 Hz)
Commit
af2a83e
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
19.0 MB · 38.0 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
-0.16
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