SAILPLANE CARRY-THROUGH STRUCTURES MADE WITH COMPOSITE-MATERIALS

The carry-through structure, which joins and transmits toads between a ircraft wings and fuselage, is a box-and-beam configuration made from composite materials In the RP series of all composite sailplanes, Incr eases in the size and weight of these aircraft increased the complexit y of their carry-through structures, RP-1 has an interference-fit, box -and-beam configuration that was repeated in RP-2, but it failed durin g static testing because of peeling of the box capstrips at about 95% of design load, Because of this failure, the RP-2 carry through was re designed with clearance between the box and beam and with pins transfe rring the bending loads: this redesign was adopted and modified for RP -3, The RP-1, RP-2, and RP-3 carry throughs and associated flight-wort hiness tests are presented here and their implications for aircraft de sign with composite materials are discussed.