Rigid Hang Glider

Overview

A rigid hang glider is a foot-launched soaring wing whose airfoil shape is held by a structural frame rather than by air pressure alone. Where a flexible hang glider relies on the sail tensioning across a simple keel and crossbar, the rigid type carries a stiff Carbon D-Cell leading edge and a row of formed Airfoil Ribs so the section stays close to its design profile across the whole speed range. That dimensional stability is what lets these wings reach glide ratios above 18:1, well beyond a typical flexible wing, at the cost of more parts, more weight, and a longer rig time.

The pilot flies prone, hung from the Keel Tube by a Hang Strap and enclosed in a Prone Harness pod. Control comes from two sources working together: shifting body weight against the Control Frame, and operating Spoileron Panel panels on the wingtips for crisp roll authority that weight shift alone cannot give on a high-aspect-ratio wing.

Wing structure

The structural heart is the Rigid Wing. Its load path begins at the Carbon D-Cell, a closed carbon/epoxy torsion box that forms the front third of the airfoil and resists both bending and twist. Behind it, the Main Spar in 7075-T6 aluminium runs the span and takes most of the bending moment, while roughly 28 foam-cored Airfoil Ribs hold the Dacron Sail to its intended camber. The sail itself is a resin-coated woven Dacron skin, laced and tensioned over the ribs so it does not balloon at speed. Pre-bent Trailing Batten rods set the trailing-edge shape, and moulded Wingtip Fairing fairings clean up the tip flow to cut induced drag. A King Post standing above the keel anchors the upper bracing.

Control system

Pitch is managed mainly by weight shift fore and aft on the Base Bar, the streamlined bar the pilot grips between the two Down Tube uprights. Roll is where the rigid wing differs most. Each tip carries a Spoileron Panel, an upper-surface panel that lifts to spoil lift on one side. Pilot input travels through Control Pushrod pushrods and Bellcrank levers running on Ball Bearing pivots, so a small hand or weight movement raises the spoiler and rolls the glider. A separate variable-geometry circuit of VG Pulley sheaves and a VG Rope lets the pilot retension the whole sail in flight, trading the slow, stable low-tension setting for a flatter, faster profile when on glide.

Rigging and airframe

The Rigging triangulates the airframe with stainless cable. Lower Flying Wires carry flight loads while the wing is loaded in the air, and upper Landing Wires from the king post support the structure on the ground when the load reverses. Spreader Bar bars hold the wires apart to widen the bracing base, and each cable terminates in a swaged Cable Thimble. Turnbuckle adjusters set wire tension and fine trim, and the leading edges plus front wires all converge at the steel Nose Plate. The control triangle bolts together through Corner Bracket fittings and a Fastener Set.

Pilot harness

The Prone Harness is a prone cocoon. After launch the pilot draws their legs into the Harness Pod pod and closes the Pod Zipper to reduce drag. Load passes through a locking Main Carabiner into Suspension Webbing suspension webbing, and a Back Plate stiffens the pod and protects the spine. A hand-deployed Reserve Parachute parachute rides in a front container as the last line of defence in a structural failure or unrecoverable tumble.

Instruments

Soaring flight depends on reading the air, so the Instrument Pod pod clamps to the base bar through a Instrument Mount. The Variometer converts pressure change into an audio tone so the pilot can center thermals without looking down. A GPS Logger logs the track for navigation and competition validation, and a Airspeed Indicator indicator fed from a pitot keeps the pilot above stall and below the never-exceed speed. The electronics build on a Bare PCB carrying an Microcontroller, SMD Passive (R/C/L), and two Pressure Sensor elements for static and pitot pressure.

Materials and use

Rigid hang gliders mix carbon/epoxy in the D-cell and spoilers with 7075 and 6061 aluminium tube in the spar, keel, and frame, plus 4130 steel for the loaded fittings. The result lands around 40 to 55 kg empty, heavier than a flexible wing but light enough for one person to carry to a launch. Pilots fly them in cross-country soaring and competition where the extra glide pays off over long glides between thermals. Setup takes longer than a flexible wing because the ribs, battens, and wires all have to be fitted and tensioned, and the wing is more sensitive to correct VG and trim, which is why these are flown by experienced pilots rather than as a first wing.