How does the UAV airbag inflate without gas or pumps?

The airbag is based on proven paragliding airbag technology, using a self-inflating design that draws air directly from ambient airflow during descent. No compressed gas cylinders, pumps or pyrotechnic inflators are needed. An internal mast with a ducted fin inflates first, then relative airflow fills the full airbag through a ram-air intake.

What is the purpose of the internal mast and ducted fin?

The internal mast inflates first and almost instantly due to its small volume. The ducted fin inside the mast initiates airflow, creating a stable and efficient pathway for rapid airbag inflation. Once pressurized, the mast directs airflow into the forward-facing ram-air intake, which expands the full-size airbag.

Project · UAV airbag

Self-inflatable airbag for a 75 kg UAV

Q: Which UAV size is the airbag designed for, and how was it tested?

The system is specifically designed for UAVs weighing up to 75 kilograms, providing energy absorption and structural protection during landing. Extensive drop trials and real UAV recovery tests confirmed inflation speed, durability and impact-force reduction. Acceleration and force measurements were used to refine the optimal outlet size and configuration.

A self-inflatable airbag for a 75 kg UAV fills a very large volume in the shortest possible time – synchronised with parachute descent, with no compressed gas or pump.

Landed fixed-wing UAV resting on its inflated airbag in a desert landscape

The challenge

Designing a reliable recovery system for UAVs requires ensuring safe landings with minimal impact forces. For a 75-kilogram UAV, the greatest challenge was inflating a very large airbag volume in the shortest possible time. The inflation process needed to perfectly align with the descent phase after parachute deployment – any delay would compromise protection at impact. Meeting this requirement demanded a lightweight, compact and ultra-fast deployment solution.

Proven self-inflation concept

APCO adapted technology from paragliding harness airbags, which have demonstrated reliability for decades. These systems are self-inflating, drawing air directly from ambient airflow and eliminating the need for heavy compressed-gas cylinders or pumps.

Internal mast with ducted fin

The UAV airbag incorporates an internal mast that inflates almost instantly due to its low volume. This mast includes a ducted fin that initiates airflow, creating a stable pathway for rapid inflation.

Fixed-wing UAV descending with an inflated airbag below the fuselage against a blue sky — Airbags

Ram-air assisted inflation

Once the mast is pressurized, it directs airflow into a forward-facing ram-air intake. As the UAV descends under parachute, the relative airflow rams into this intake, rapidly expanding the full-size airbag. This dual-phase sequence – ducted fin plus ram-air intake – delivers complete inflation significantly faster than conventional systems.

Airbag compartment on the underside of a UAV fuselage with a red safety flag

Results

Fast deployment: inflation is synchronized with the UAV’s parachute descent profile.
Lightweight and compact: requires no heavy components, minimizing battery and payload burden.
Proven reliability: built on decades of paragliding airbag expertise, validated in thousands of impact events.
Controlled deflation: engineered valves release air at touchdown, preventing damage and absorbing energy for softer landings.

Testing and validation

Extensive drop trials and real UAV recovery tests confirmed the system’s inflation speed, durability and impact-mitigation capability. Acceleration and force measurements were used to refine the optimal outlet size and configuration. Results consistently demonstrated safe landings, protecting sensitive avionics and structural components while ensuring mission-ready recovery.

Technical data per manufacturer documentation from APCO Aviation Ltd , as of 2026-09-22.