Source: https://guthlabs.ai/docs/instruments/hohmann-transfer-delta-v/implementation/

instrument implementation / implementation-contract

# Hohmann Transfer Delta-V implementation

A source-bound implementation contract for Hohmann Transfer Delta-V; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t6-080

**Effect**: Computation or source lookup only

## Input and validation requirements

The zero-radius input causes division by zero and undefined orbital quantities; the instrument must reject it. The specification also leaves signed-versus-magnitude delta-v and unit conventions ambiguous.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "central_body": "Earth",
    "mu_km3_s2": 398600.4418,
    "initial_radius_km": 7000,
    "target_radius_km": 14000
  },
  "expected_outputs": {
    "transfer_semi_major_axis_km": 10500,
    "delta_v1_km_s": 1.16738,
    "delta_v2_km_s": 0.97915,
    "total_delta_v_km_s": 2.14653,
    "transfer_time_s": 5353.83
  },
  "working": "a_t=(7000+14000)/2=10500 km. v_c1=sqrt(398600.4418/7000)=sqrt(56.9429203)=7.546053 km/s. v_p=sqrt(398600.4418*(2/7000-1/10500))=8.713432 km/s. Δv1=|8.713432-7.546053|=1.167379 km/s. v_c2=sqrt(398600.4418/14000)=5.335865 km/s. v_a=sqrt(398600.4418*(2/14000-1/10500))=4.356716 km/s. Δv2=|5.335865-4.356716|=0.979150 km/s. Total=1.167379+0.979150=2.146529 km/s. t=pi*sqrt(10500^3/398600.4418)=5353.83 s."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/hohmann-transfer-delta-v/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/hohmann-transfer-delta-v/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/hohmann-transfer-delta-v/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche6/tranche6-results.json`