FA-69757 / Orbital propagation / Member archive

Clohessy-Wiltshire relative motion: Along-track secular drift is missing the 1/n scale · case 02

Along-track drift from a velocity offset is scaled by n.

Member previewVariant 2 · 3 implementations · 7 checks per implementation

Case contract

Input [x0,y0,z0,vx0,vy0,vz0,n,t] with x radial, y along-track, z cross-track about a circular reference orbit of mean motion n. Return [x,y,z,vx,vy,vz] from the closed-form HCW solution, rounded to 6.

Why this case matters

Orbit determination and mission planning chain many small conversions; one wrong branch or unit silently moves a spacecraft by kilometres.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
clohessy-wiltshire relative motion [0.2, -1.0, 0.1, 0.0005, -0.0003, 0.0, 0.0011, 3000.0]	`[0.236705, -6.952935, -0.098748, -0.000503, -0.000381, 1.7e-05]`	`[0.236705, -4.084008, -0.098748, -0.000503, -0.000381, 1.7e-05]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.