Huchez develops aircraft pressure testing winch for Airbus24 January 2012
Designed to the specific technical requirements requested by Airbus, the aluminium winch includes a pressure sensor, which is attached by the rope to a tube that measures atmospheric pressure outside the aircraft during flight.
While the tube is being dragged 60–120m behind the aircraft’s tail, it feeds back data to the pressure sensor on the winch via a pneumatic rotating collector, and this value is used as the reference point (marked as zero).
Resulting from a year’s worth of design work at Huchez Engineering, the firm’s design and engineering department, the winch collects a range of data including the stress on the rope, the rope’s unwound length and the pressure value to within 1Pa.
The rope was also cross-wound to enable precision monitoring of the rope winding quality.
Huchez engineer Stéphane Guillossou, who headed up the work for Airbus, said: “The four winches we made for Airbus are reliable, tested tools that met the requirements of Airbus. They allow the performance of a plane to be adjusted, measured and assessed. These are working tools.”
Airbus ordered another three of these winches, which have already been delivered and installed.
The specially designed winches had to take into account the constraints of the aircraft, which meant its weight and size had to be carefully considered, not only to enable its passage between the seats, but also to factor into its crash resistance during a significant impact.
Constructed from aluminium, the winch weighs 165kg, and has a haulage capacity of 150kgs at hoist speeds of up to 30m per minute. The 140m-long wire rope used has a 9.5mm diameter.
Functions featured on the winch include a variable speed drive and a rope anti-stretch system, along with a position measurement system that measures the amount of rope released.
It can be controlled directly using its control panel or from the airplane’s flight deck, and features communication links to Airbus’ own integrated data systems. Other software includes a maintenance mode for diagnosing problems, and it also includes hardware and software limit switches.