skylight.

AIC4174 Air India Limited

Boeing 777 337ER · VT-ALJ · SFO → CCU

· 0:53Quality 66nose/tail

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −77%). 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
61%
First lockfrom target selected
19.2 s
Centring, medianaz / el while locked
1.03° / 0.78°
Centring, 90th pctaz / el while locked
4.44° / 4.88°
Tightest field of viewhorizontal
3.4°
Time to 8°from first lock
30.1 s
Time to tightestfrom first lock
—
Time at telefield of view ≤ 5.5°
2.7 s
Jitter at teleaz / el, standard deviation
—
Swing at teleaz / el, peak to peak
—
Pan reversalsper 10 s at tele
0.0
Largest pan hopin any 1 s at tele
—
Largest tilt hopin any 1 s at tele
—
Pose error, mediancommand vs camera
1.53°
Largest correctionvision vs prediction
1.46°
Zoom steps
52

Aircraft & route

Flight
AIC4174
Registration
VT-ALJ
Type
Boeing 777 337ER (B77W)
Airline
Air India Limited
From
SFO · San Francisco
To
CCU · Kolkata
Ground speed
212 kt
Altitude at closest
975 ft
Vertical rate
+3,072 ft/min
Category
A5
ICAO hex
8003e2

Pass geometry

Max elevation
80.7°
Elevation at start → end
0.0° → 11.9°
Azimuth at start → end
116° ESE → 299° WNW
Closest-approach azimuth
27° NNE
Minimum slant range
327 m
Heading at closest
297° WNW
Aspect at closest
nose/tail (5°)
Turn
straight (0°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
0:53 (52.5 s)
Lock
61%

Build & tuning

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

Build
2026-10-15p — selection hysteresis; auto-cal drops stale bias
Commit
b8aa462
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
26.0 MB · 52.0 s · offset -1.1 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