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Concept render of ANGEL, a solar-electric high-altitude platform with an ultra-long wing and twin propellers flying above a cloud layer.

Aerospace · CONCEPT

ANGEL: A European HAPS Concept for Persistent Stratospheric Operations

ANGEL is a conceptual solar-electric high-altitude platform built around an ultra-high-aspect-ratio wing, twin electric propulsion and day-night energy storage. This review examines the proposed design envelope, its potential mission value and the engineering work still required before any claim of validation.

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