skylight.

CPA879 Cathay Pacific

Boeing 777 367ER · B-KQY · SFO → HKG

· 1:05Quality 86nose/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
65%
First lockfrom target selected
5.3 s
Centring, medianaz / el while locked
0.30° / 0.47°
Centring, 90th pctaz / el while locked
2.08° / 4.50°
Tightest field of viewhorizontal
4.1°
Time to 8°from first lock
41.8 s
Time to tightestfrom first lock
55.9 s
Time at telefield of view ≤ 5.5°
9.0 s
Jitter at teleaz / el, standard deviation
0.36° / 0.37°
Swing at teleaz / el, peak to peak
1.15° / 1.16°
Pan reversalsper 10 s at tele
2.2
Largest pan hopin any 1 s at tele
0.71°
Largest tilt hopin any 1 s at tele
0.95°
Pose error, mediancommand vs camera
0.78°
Largest correctionvision vs prediction
0.98°
Zoom steps
50

Aircraft & route

Flight
CPA879
Registration
B-KQY
Type
Boeing 777 367ER (B77W)
Airline
Cathay Pacific
From
SFO · San Francisco
To
HKG · Hong Kong
Ground speed
208 kt
Altitude at closest
1,150 ft
Vertical rate
+3,072 ft/min
Category
A5
ICAO hex
780a97

Pass geometry

Max elevation
86.1°
Elevation at start → end
0.1° → 11.8°
Azimuth at start → end
116° ESE → 299° WNW
Closest-approach azimuth
41° NE
Minimum slant range
372 m
Heading at closest
297° WNW
Aspect at closest
nose/tail (3°)
Turn
straight (0°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
1:05 (65.1 s)
Lock
65%

Build & tuning

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

Build
2026-10-15q — drive speed latched at the lens position; measured speed bytes only; auto-cal keeps gains
Commit
44f2d6a
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
31.4 MB · 63.2 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
-0.27
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