# How a Host Spacecraft Refuels Another Satellite Without Using Its Fuel Tank

> A system where a host satellite carries and attaches small, non-propelled fuel modules to other satellites, feeding propellant directly into their engines to bypass damaged or empty onboard storage.

- **Patent:** US 11124318
- **Original title:** Spacecraft servicing devices and related assemblies, systems, and methods
- **Owner:** Northrop Grumman Systems Corp
- **Granted:** 2021
- **Status:** Active
- **Times cited:** 1
- **Field:** aerospace, mechanical

## What it does

This system describes a 'mothership' spacecraft that carries multiple small, independent servicing devices. When a target satellite needs a boost but cannot use its own fuel system, the host deploys one of these devices. The device attaches to the target and connects directly to the propulsion system, bypassing the target's existing fuel tanks entirely. This allows the host to service multiple satellites in one mission by dropping off these 'external fuel packs' one by one.

## What it does NOT cover

- Does not cover servicing devices that have their own independent propulsion systems for maneuvering.
- Does not cover traditional refueling methods where fuel is transferred into the target's existing storage tanks.
- Does not cover autonomous docking systems that do not involve a host spacecraft deploying a separate servicing device.

## The clever bit

The system bypasses the target's fuel storage entirely. By feeding propellant directly into the propulsion lines, it ignores the target's potentially broken or incompatible internal plumbing.

## Real-world examples

1. Northrop Grumman Mission Extension Vehicles (MEV)
2. Future orbital satellite life-extension missions

## Why it matters

As satellites age, they often run out of fuel while their electronics remain functional. This patent provides a path for extending the life of expensive orbital assets by providing a 'plug-in' fuel source, potentially saving operators billions in replacement costs.

## Frequently asked questions

### What does How a Host Spacecraft Refuels Another Satellite Without Using Its Fuel Tank cover?

A system where a host satellite carries and attaches small, non-propelled fuel modules to other satellites, feeding propellant directly into their engines to bypass damaged or empty onboard storage.

### Who owns patent US 11124318?

Northrop Grumman Systems Corp owns this patent, granted in 2021.

### When does this patent expire?

This patent is expected to expire on September 21, 2041, when the invention enters the public domain.

### What is patent US 11124318 cited by?

This patent has been cited by 1 later patents that build on its ideas.

### What problem does this patent solve?

As satellites age, they often run out of fuel while their electronics remain functional. This patent provides a path for extending the life of expensive orbital assets by providing a 'plug-in' fuel source, potentially saving operators billions in replacement costs.

### What does this patent NOT cover?

Does not cover servicing devices that have their own independent propulsion systems for maneuvering.

**Full plain-English explainer:** https://patentbrief.org/patent/us/11124318/starship-belly-flop-maneuver

**Original patent:** https://patents.google.com/patent/US11124318

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_Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._