Thermoformed cascades for jet engine thrust reversers

A method of fabricating a cascade grid panel for a jet engine thrust reverser, the method comprising:

• forming a strongback assembly from a plurality of continuous fiber-reinforced thermoplastic strongbacks that are spaced apart to form slots between adjacent strongbacks;
• assembling a plurality of discontinuous fiber-reinforced thermoplastic vanes, a set of hard tool inserts, and a set of expandable soluble mandrels within the slots of the strongback assembly to form a preassembled cascade grid panel wherein forming the preassembled cascade grid panel includes:
• placing the hard tool inserts into alternating ones of cavities defined by the thermoplastic vanes along the slots;
• and
• placing expandable soluble mandrels into remaining ones of the cavities including between the alternating cavities;
• and
• co-consolidating the preassembled cascade grid panel under heat and pressure to form the cascade grid panel, wherein the applied heat and pressure expand the expandable soluble mandrels to compress the thermoplastic vanes against the thermoplastic strongbacks and hard tool inserts during the co-consolidating.