FAILURE MAP
← Case archive

FA-69641 / Orbital propagation / Open access

Hohmann transfer budget: Transfer semi-major axis is the sum of radii · case 01

Transfer orbit is twice too large.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

a is taken as r1+r2 instead of the mean.

VERIFIED REPAIR

Use (r1+r2)/2.

Unsuccessful approach: The geometric mean is not the ellipse semi-major axis.

Case contract

Input [r1, r2, mu] circular radii. Transfer a=(r1+r2)/2; burn 1 = |v_peri - v_circ1|, burn 2 = |v_circ2 - v_apo| using vis-viva at each end; time of flight is half the transfer period. Works inward (r2<r1) too. Return [dv1, dv2, total] rounded 6 and tof rounded 3.

Why this case matters

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

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    r1,r2,mu=x
    at=r1+r2
    v1=math.sqrt(mu/r1); v2=math.sqrt(mu/r2)
    vp=math.sqrt(mu*(2/r1-1/at)); va=math.sqrt(mu*(2/r2-1/at))
    dv1=abs(vp-v1); dv2=abs(v2-va)
    tof=math.pi*math.sqrt(at**3/mu)
    return [round(dv1,6),round(dv2,6),round(dv1+dv2,6),round(tof,3)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53])], [('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454])], [('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hohmann transfer budget [7000.0, 7500.0, 398600.4418][1.7489, 1.586968, 3.335868, 8688.264][0.129002, 0.126795, 0.255797, 3071.765]Failed
hohmann transfer budget [1.0, 1.524, 1.0][0.266414, 0.14711, 0.413523, 12.597][0.098912, 0.088971, 0.187883, 4.454]Failed
hohmann transfer budget [6778.0, 6778.0, 398600.4418][1.723487, 1.723487, 3.446973, 7853.773][0.0, 0.0, 0.0, 2776.728]Failed
hohmann transfer budget [10000.0, 7000.0, 398600.4418][1.188052, 1.963876, 3.151928, 11029.463][0.58409, 0.638791, 1.222881, 3899.504]Failed
hohmann transfer budget [7000.0, 8000.0, 398600.4418][1.798061, 1.489807, 3.287869, 9141.509][0.247477, 0.239347, 0.486825, 3232.011]Failed
hohmann transfer budget [8000.0, 7000.0, 398600.4418][1.489807, 1.798061, 3.287869, 9141.509][0.239347, 0.247477, 0.486825, 3232.011]Failed
hohmann transfer budget [1.0, 1.2, 1.0][0.243163, 0.188093, 0.431256, 10.251][0.044466, 0.042483, 0.086949, 3.624]Failed

SHA-256 / 16da4a5b7a22ed327da470141dd07ce68f713a6ca49e1ea0ce0821073c3a7901

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    r1,r2,mu=x
    at=math.sqrt(r1*r2)
    v1=math.sqrt(mu/r1); v2=math.sqrt(mu/r2)
    vp=math.sqrt(mu*(2/r1-1/at)); va=math.sqrt(mu*(2/r2-1/at))
    dv1=abs(vp-v1); dv2=abs(v2-va)
    tof=math.pi*math.sqrt(at**3/mu)
    return [round(dv1,6),round(dv2,6),round(dv1+dv2,6),round(tof,3)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53])], [('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454])], [('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hohmann transfer budget [7000.0, 7500.0, 398600.4418][0.12687, 0.129079, 0.255949, 3069.025][0.129002, 0.126795, 0.255797, 3071.765]Failed
hohmann transfer budget [1.0, 1.524, 1.0][0.090852, 0.101315, 0.192167, 4.309][0.098912, 0.088971, 0.187883, 4.454]Failed
hohmann transfer budget [6778.0, 6778.0, 398600.4418][0.0, 0.0, 0.0, 2776.728][0.0, 0.0, 0.0, 2776.728]Passed
hohmann transfer budget [10000.0, 7000.0, 398600.4418][0.649717, 0.592987, 1.242704, 3808.066][0.58409, 0.638791, 1.222881, 3899.504]Failed
hohmann transfer budget [7000.0, 8000.0, 398600.4418][0.239871, 0.248041, 0.487912, 3221.232][0.247477, 0.239347, 0.486825, 3232.011]Failed
hohmann transfer budget [8000.0, 7000.0, 398600.4418][0.248041, 0.239871, 0.487912, 3221.232][0.239347, 0.247477, 0.486825, 3232.011]Failed
hohmann transfer budget [1.0, 1.2, 1.0][0.042655, 0.044657, 0.087312, 3.602][0.044466, 0.042483, 0.086949, 3.624]Failed

SHA-256 / f2b0dca7a66d6ef90f6d1c20380426442809826df89baa1f13740d1896a6ccf0

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(x):
    r1,r2,mu=x
    at=(r1+r2)/2
    v1=math.sqrt(mu/r1); v2=math.sqrt(mu/r2)
    vp=math.sqrt(mu*(2/r1-1/at)); va=math.sqrt(mu*(2/r2-1/at))
    dv1=abs(vp-v1); dv2=abs(v2-va)
    tof=math.pi*math.sqrt(at**3/mu)
    return [round(dv1,6),round(dv2,6),round(dv1+dv2,6),round(tof,3)]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53])], [('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454])], [('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765]), ('hohmann transfer budget [1.0, 1.524, 1.0]', [1.0, 1.524, 1.0], [0.098912, 0.088971, 0.187883, 4.454]), ('hohmann transfer budget [6778.0, 6778.0, 398600.4418]', [6778.0, 6778.0, 398600.4418], [0.0, 0.0, 0.0, 2776.728]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624])], [('hohmann transfer budget [7000.0, 8000.0, 398600.4418]', [7000.0, 8000.0, 398600.4418], [0.247477, 0.239347, 0.486825, 3232.011]), ('hohmann transfer budget [8000.0, 7000.0, 398600.4418]', [8000.0, 7000.0, 398600.4418], [0.239347, 0.247477, 0.486825, 3232.011]), ('hohmann transfer budget [10000.0, 7000.0, 398600.4418]', [10000.0, 7000.0, 398600.4418], [0.58409, 0.638791, 1.222881, 3899.504]), ('hohmann transfer budget [1.0, 1.2, 1.0]', [1.0, 1.2, 1.0], [0.044466, 0.042483, 0.086949, 3.624]), ('hohmann transfer budget [1.3, 1.0, 1.0]', [1.3, 1.0, 1.0], [0.059197, 0.063219, 0.122416, 3.874]), ('hohmann transfer budget [6778.0, 7178.0, 398600.4418]', [6778.0, 7178.0, 398600.4418], [0.109121, 0.107568, 0.216689, 2900.53]), ('hohmann transfer budget [7000.0, 7500.0, 398600.4418]', [7000.0, 7500.0, 398600.4418], [0.129002, 0.126795, 0.255797, 3071.765])]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hohmann transfer budget [7000.0, 7500.0, 398600.4418][0.129002, 0.126795, 0.255797, 3071.765][0.129002, 0.126795, 0.255797, 3071.765]Passed
hohmann transfer budget [1.0, 1.524, 1.0][0.098912, 0.088971, 0.187883, 4.454][0.098912, 0.088971, 0.187883, 4.454]Passed
hohmann transfer budget [6778.0, 6778.0, 398600.4418][0.0, 0.0, 0.0, 2776.728][0.0, 0.0, 0.0, 2776.728]Passed
hohmann transfer budget [10000.0, 7000.0, 398600.4418][0.58409, 0.638791, 1.222881, 3899.504][0.58409, 0.638791, 1.222881, 3899.504]Passed
hohmann transfer budget [7000.0, 8000.0, 398600.4418][0.247477, 0.239347, 0.486825, 3232.011][0.247477, 0.239347, 0.486825, 3232.011]Passed
hohmann transfer budget [8000.0, 7000.0, 398600.4418][0.239347, 0.247477, 0.486825, 3232.011][0.239347, 0.247477, 0.486825, 3232.011]Passed
hohmann transfer budget [1.0, 1.2, 1.0][0.044466, 0.042483, 0.086949, 3.624][0.044466, 0.042483, 0.086949, 3.624]Passed

SHA-256 / 515df430ed12a3665f5af58e948392f2a189fc8ac94f14e799664e72ef961e89

Verification & scope

A deterministic toy two-body model with stipulated constants and conventions; not flight dynamics software or a validated SGP4 implementation. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:48:13.228570+00:00.

Case digest / 3618280d8067ac10dfd3037288a2bb8b962bc4aa5fe808a5eff43969f4664e92