
Fan Blades
Hercules are very proud to supply fan blade maintenance and refurbishment services to the Aircraft Research Association's transonic wind tunnel.
In operation since 1956, the ARA tunnel continues to carry out cutting edge aerodynamic research at air velocities of up to mach 1.4.
The blades are carved from mahogany, many if which date back to the 1950's.
We have developed detailed inspection, repair and refurbishment schemes including composite coverings and high performance paint finishes to increase the blade's protection from high velocity debris when in service.



FAN BLADES




New Manufacture
Using the same techniques and standards as our wooden aircraft propellers, Hercules manufactures blades for wind tunnels and fans. Blades can be designed and manufactured for bespoke applications, made from current designs or reverse engineered from existing blades. Provision for mounting blades can be incorporated and manufactured as required. Plates, bushes or adaptors can be made from aluminium or steel.


Blade Finishing
Hercules are experienced in the application of fibre glass coverings to wooden blade structures. Finishes and colours are then applied to the same high specifications as our aircraft propellers, in our standard colours or to bespoke customer requirements. Hercules considers Safety and Quality to be as important for ground-operated blades as it is for blades used in flight.
Wind Tunnel Fan Manufacture
Narvik University in Norway run a wind tunnel as part of their aerodynamics department. The fan became damaged during one experiment, doing terminal damage to all the blades.
The university needed an exact copy to replace the damaged fan, so they sent it to us to reproduce.
The blade profiles were recreated using our Coordinate Measuring Machine (CMM), then a 3D CAD model created. From there the first challenge was to build the laminated four blade blank, using the traditional method of alternating solid and split layers to create a consistently strong blank.
The blank was then machined using our CNC, one blade at a time, prior to having the hub hand crafted and the hub shroud created using the traditional plywood method. Once complete the fan and nose-bowl (which also needed some repair for dents it had received during the incident) were painted using a colour matched paint.





