Purpose

This entry is for developing a persistent near space solid lighter than air reconnaissance and communications platform that would in many instances take the place of a satellite, be considerably more maneuverable, cheaper to make and operate, and produce better quality images while lingering in trouble spots indefinitely. Targets of present satellite based surveillance systems often schedule their day based on exposure to satellites schedule. The proposed solid lighter than air vehicle has the ability to linger over a target at very high altitude (near Space) for indefinite periods requiring no fuel. The parabolic airship is a flying hot air solar furnace, and utilizes the Sun above and the intense cold of the upper atmosphere in its shadow to make the perfect environment for a Stirling powered vehicle. The infinite loop design is a natural for single and especially multiple piston Stirling engines, due to its simplicity, having no connecting rods, crankshaft, flywheel or valve train.

Executive Summary

The communications and imaging platform and vehicle proposed is an adjustable volume remote controlled hybrid lifting body and hot air airship with a unique:

1. Solar Stirling engine/generator allowing the craft to stay aloft almost indefinitely, no fuel required.

2. Polyimide aerogel lighter than air construction.

3. Parabolic shape with stealth characteristics

4. Inertial drive

5. Variable pitch vector propellers

6. High efficiency magnetic levitation electric motors.

Aerogel Parabolic Airship

The lighter than air lifting body is primarily made from polyimide aerogel in which the air is replaced with hydrogen or helium and encapsulated with graphene, resulting in a flexible strong material that is lighter than air. The craft consists of two parabolic dishes of different fineness joined in the middle. The lower dish being flatter than the upper, to create a lifting body. Together they comprise an insulated solar concentrator. Both domes are made primarily of aerogel reinforced with carbon nanotubes the upper being as transparent as possible the lower being coated inside with either aluminized Mylar or some other material to provide reflectivity the purpose of which to create a solar furnace to power the Stirling engine. The hot end of which is at the concentrator focal. The Infinite Loop Stirling engine is cylindrical in shape with the bottom, cold end extending out beyond the lower parabolic dish into the frigid high altitude air in the shadow of the dish below. Besides the internal electric generator, within the Infinite loop Stirling engine the navigational fins are covered with high efficiency thin-film solar cells. Either lightweight electric motors are used or a direct-geared drive shaft transfers the power through a transmission perpendicular to the engine extending out parallel to the air ship to drive variable pitch propellers. Fins are provided at the rear of the ship to provide directional control and stability and additional solar photovoltaic power.

Propulsion

Infinite loop Stirling Engine/Generator

The double acting infinite loop Stirling engine has pistons, but no connecting rods crankshaft or flywheel.

The pistons run in infinite loops subject of patent US6629513 Inertial Engine