Feasibility Study about the Usage of Composite Material on Conair’s Q400 Air Tanker (Bachelorarbeit)

Kurzfassung

Conair Group, a fire fighting company in Abbotsford, BC, uses the Q400 as an air tanker. This airplane has a retardant capacity of 2,642 US gallons and a flight range of 3.5 hours at maximum take-off weight. An increase in retardant and fuel capacity would position Conair better in the global market. This can be achieved through either increasing OEM limits (e.g. max take-of weight) or by reducing the aircraft’s mass. The latter will be subject to this thesis. The current tank is made of aluminum and consequently offers an immense weight-saving potential if manufactured with composite material. In the presented thesis, the tank and its requirements are analyzed. Along with the mass distribution of the tank the data is used to create two new concepts. The first conceptual tank is made of thermoset composites. The parts are produced through infiltration technologies such as VARI. Due to the low processing temperatures, the costs for this concept are modest. The thermosetting polymers' weakness is to be found in the joining of the pieces and is labor-intensive. The second conceptual tank is made from thermoplastic composites. Through modern technologies, such as automated fiber placement, integral structures can be manufactured automatically. These parts can be joined by welding. The raw material and the tooling are more expensive for the thermoplastic concept compared to the thermoset one. The new concepts are compared to the current tank design using a decision matrix. The composite concepts outperform the aluminum tank assessed on the selected criteria. Since implementing a new tank design is a complicated step, Conair should gain experience with composites in the first step. Simple parts, as the side fairings or torque tubes, are less complex to composites. Also, the fairings cost can be reduced by using a foam core instead of a honeycomb core. In the long term, the tank should be replaced by a composite one.