Platform · multi-stage deceleration

High-velocity drogue parachute

Decelerating a very fast-moving object requires carefully engineered multi-stage solutions that withstand extreme aerodynamic forces.

Large orange and white band parachute during a test in a wind tunnel hall

Several stages, several means

Whether in defense, aerospace or UAV recovery, high-velocity recovery systems often combine several steps:

  • Parachute systems with staged deployment using opening sleeves, sliders, reefing devices or staged canopies.
  • Textile drag devices such as deceleration rings, drag cones and drag plates, designed purely to create drag without functioning as a full parachute.
  • Inflatable aerodynamic decelerators — e.g. ballute (attached inflatable decelerator), inflatable drag ring, paraflap, inflatable paraskirt or inflatable ring decelerator. They offer a high strength-to-weight ratio and can function in subsonic, transonic and supersonic regimes.
Rendering of a space capsule with a deployed inflatable decelerator above the earth
Line drawing of a round canopy with a band running around its equator and vent slots in the gores

Common inflatable designs

Inflatable decelerators come in several basic forms:

  • Inflatable drag ring: a circular ring that inflates to create uniform drag with minimal oscillation.
  • Paraflap: textile panels that deploy outward to increase drag and stability.
  • Inflatable paraskirt: an inflatable skirt structure that increases frontal area for enhanced deceleration.
  • Hybrid inflatable-cone devices: designs combining conical drag surfaces with inflatable rings for stability.
Sketches of inflatable decelerators on a projectile body: inflatable drag ring, paraflap, inflatable paraskirt and two cone-shaped designs

Friction is the enemy

A critical design factor is eliminating friction between connected parts during deployment. At extreme speeds, heat and friction can cut through even the strongest materials. Low-friction fabrics such as PTFE (Teflon)-coated textiles are used, and relative movement between elements is minimised by design to prevent abrasion.

Red and white decelerator canopy on a tether line during a wind tunnel test

Damage analysis is part of it

When lines, bridles or risers break, identify whether the cause was tensile overload or friction-induced melting. Metal hardware must be free from burrs, debris and sharp edges. CNC-machined items often require polishing to meet that standard; extruded metal components are generally preferable for high-velocity applications.

Products
Deceleration parachutesInflatables & landing pads
Environments
Supersonic recoveryFire and heat resistance

Source: apcodefense.com (APCO Aviation), as of 25 September 2026.

Frequently asked

Asked in technical terms.

How is a very fast-moving object decelerated?

In multiple stages. Common are parachute systems with staged deployment using opening sleeves, sliders or reefing, plus textile drag devices such as deceleration rings, drag cones and drag plates, and inflatable decelerators like ballute, drag ring, paraflap or paraskirt, working in subsonic, transonic and supersonic regimes. Inflatable decelerators offer a high strength-to-weight ratio.

Why is friction a critical design factor?

Because at extreme speeds heat and friction can cut through even the strongest materials. Low-friction fabrics such as PTFE-coated textiles are therefore used. The design should minimise relative movement between connected components during deployment, as far as possible, to prevent abrasion.

Which inflatable decelerator designs are common?

The inflatable drag ring is a circular ring that creates uniform drag with minimal oscillation. On the paraflap, textile panels deploy outward to increase drag and stability. The inflatable paraskirt uses a skirt structure to increase frontal area. Hybrid inflatable-cone devices combine conical drag surfaces with inflatable rings for stability.

Tell us what the system has to do.

Define a project

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