skylight.

UAL990 United

Boeing 777 224ER · N77012 · SFO → CDG

· 1:27Quality 97side-on

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −85%). 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
84%
First lockfrom target selected
12.6 s
Centring, medianaz / el while locked
0.41° / 0.24°
Centring, 90th pctaz / el while locked
9.41° / 6.35°
Tightest field of viewhorizontal
4.1°
Time to 8°from first lock
50.5 s
Time to tightestfrom first lock
65.8 s
Time at telefield of view ≤ 5.5°
13.1 s
Jitter at teleaz / el, standard deviation
0.16° / 0.16°
Swing at teleaz / el, peak to peak
0.74° / 0.67°
Pan reversalsper 10 s at tele
3.0
Largest pan hopin any 1 s at tele
0.78°
Largest tilt hopin any 1 s at tele
0.55°
Pose error, mediancommand vs camera
0.78°
Largest correctionvision vs prediction
6.63°
Zoom steps
54

Aircraft & route

Flight
UAL990
Registration
N77012
Type
Boeing 777 224ER (B772)
Airline
United
From
SFO · San Francisco
To
CDG · Paris
Ground speed
182 kt
Altitude at closest
1,350 ft
Vertical rate
+2,304 ft/min
Category
A5
ICAO hex
aa6b9d

Pass geometry

Max elevation
80.0°
Elevation at start → end
0.1° → 12.0°
Azimuth at start → end
116° ESE → 298° WNW
Closest-approach azimuth
27° NNE
Minimum slant range
442 m
Heading at closest
297° WNW
Aspect at closest
side-on (90°)
Turn
straight (0°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
1:27 (86.6 s)
Lock
84%

Build & tuning

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

Build
2026-10-16f — A/B mountPrior, cand diagnostics, clip-short flag
Commit
3ea7ff5
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
43.5 MB · 87.0 s · offset -1.3 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