skylight.

UAL1577 United

Boeing 737 MAX 9 · N17436 · SFO → ?

· 0:49side-onDead-zone wrap

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −27%). 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
69%
First lockfrom target selected
6.2 s
Centring, medianaz / el while locked
1.47° / 0.19°
Centring, 90th pctaz / el while locked
7.55° / 0.82°
Tightest field of viewhorizontal
3.4°
Time to 8°from first lock
4.7 s
Time to tightestfrom first lock
38.6 s
Time at telefield of view ≤ 5.5°
5.1 s
Jitter at teleaz / el, standard deviation
0.48° / 0.16°
Swing at teleaz / el, peak to peak
1.57° / 0.58°
Pan reversalsper 10 s at tele
0.0
Largest pan hopin any 1 s at tele
1.60°
Largest tilt hopin any 1 s at tele
0.97°
Pose error, mediancommand vs camera
1.05°
Largest correctionvision vs prediction
1.87°
Zoom steps
48

Aircraft & route

Flight
UAL1577
Registration
N17436
Type
Boeing 737 MAX 9
Airline
United
From
SFO
To
—
Ground speed
295 kt
Altitude at closest
7,825 ft
Vertical rate
+2,816 ft/min
Category
A3
ICAO hex
a12ae9

Pass geometry

Max elevation
36.3°
Elevation at start → end
36.3° → 18.5°
Azimuth at start → end
255° WSW → 207° SSW
Closest-approach azimuth
255° WSW
Minimum slant range
4.1 km
Heading at closest
185° S
Aspect at closest
side-on (70°)
Turn
straight (7°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
Yes — pan pre-positioned across the stop
Duration
0:49 (48.7 s)
Lock
69%

Build & tuning

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

Build
2026-10-13k — centred plane + noisy motion check no longer demotes the zoom
Commit
181d1fa+wip
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
24.0 MB · 48.0 s · offset -0.9 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