skylight.

UAL889 United

Boeing 777 224ER · N78002 · PEK → SFO

· 0:24Quality 70side-on

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −68%). 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
50%
First lockfrom target selected
5.1 s
Centring, medianaz / el while locked
0.54° / 0.51°
Centring, 90th pctaz / el while locked
1.16° / 3.41°
Tightest field of viewhorizontal
4.1°
Time to 8°from first lock
10.8 s
Time to tightestfrom first lock
14.7 s
Time at telefield of view ≤ 5.5°
2.1 s
Jitter at teleaz / el, standard deviation
0.00° / 0.00°
Swing at teleaz / el, peak to peak
0.00° / 0.00°
Pan reversalsper 10 s at tele
0.0
Largest pan hopin any 1 s at tele
2.96°
Largest tilt hopin any 1 s at tele
0.63°
Pose error, mediancommand vs camera
1.20°
Largest correctionvision vs prediction
1.08°
Zoom steps
21

Aircraft & route

Flight
UAL889
Registration
N78002
Type
Boeing 777 224ER
Airline
United
From
PEK · Beijing
To
SFO · San Francisco
Ground speed
258 kt
Altitude at closest
11,200 ft
Vertical rate
+64 ft/min
Category
A5
ICAO hex
aa92f9

Pass geometry

Max elevation
26.9°
Elevation at start → end
21.2° → 26.9°
Azimuth at start → end
336° NNW → 354° N
Closest-approach azimuth
354° N
Minimum slant range
7.6 km
Heading at closest
114° ESE
Aspect at closest
side-on (59°)
Turn
straight (2°)
Departure
No
Zenith pass
No
Dead-zone wrap
No
Duration
0:24 (23.7 s)
Lock
50%

Build & tuning

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

Build
2026-10-13h — no zoom-focus direct while the lens is still zooming (wedge race)
Commit
181d1fa+wip
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
11.9 MB · 24.0 s · offset -1.4 s
pursuit
velocity
maxLeadSec
3
panLatencySec
0.6
tiltLatencySec
0.4
rippleDeg
0.5
rippleTeleDeg
0.25
rateFloorDegPerDps
2.5
rateFloorMaxDeg
12
lockedSigmaDeg
0.35
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