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DAL1559 Delta Air Lines

Airbus A321-271NX · N520DE · SFO → ?

· 1:34Quality 91side-on

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −75%). 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
92%
First lockfrom target selected
7.6 s
Centring, medianaz / el while locked
0.12° / 0.11°
Centring, 90th pctaz / el while locked
0.46° / 0.36°
Tightest field of viewhorizontal
3.4°
Time to 8°from first lock
8.3 s
Time to tightestfrom first lock
59.7 s
Time at telefield of view ≤ 5.5°
69.9 s
Jitter at teleaz / el, standard deviation
0.22° / 0.20°
Swing at teleaz / el, peak to peak
1.34° / 1.79°
Pan reversalsper 10 s at tele
0.0
Largest pan hopin any 1 s at tele
4.55°
Largest tilt hopin any 1 s at tele
3.14°
Pose error, mediancommand vs camera
0.79°
Largest correctionvision vs prediction
2.35°
Zoom steps
41

Aircraft & route

Flight
DAL1559
Registration
N520DE
Type
Airbus A321-271NX
Airline
Delta Air Lines
From
SFO
To
—
Ground speed
281 kt
Altitude at closest
6,825 ft
Vertical rate
+2,496 ft/min
Category
A3
ICAO hex
a6893e

Pass geometry

Max elevation
35.0°
Elevation at start → end
21.3° → 15.6°
Azimuth at start → end
322° NW → 205° SSW
Closest-approach azimuth
266° W
Minimum slant range
3.6 km
Heading at closest
185° S
Aspect at closest
side-on (81°)
Turn
straight (6°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
1:34 (93.6 s)
Lock
92%

Build & tuning

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

Build
2026-10-16h — lock-first association on (A/B −40% tele gaps)
Commit
dfc3684
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
47.0 MB · 94.0 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
-0.06
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