HELICOPTER AIRFRAME STRUCTURE Russian patent published in 2015 - IPC B64C1/00 B64C27/04 

FIELD: transport.

SUBSTANCE: invention relates to production of helicopters. Helicopter airframe comprises torsion box with propulsion reduction gear support and shaped element extending along the height of said torsion box, undercarriage attachment brackets, support element for engine attachment, bottom with lengthwise elements, cabin floor deck and outer skin coupled with torsion box. Torsion box comprises first zone its cavity being composed by fuel compartment and second zone arranged above the first one and partially composed by the support made as structural panel with L-like flanges with shaped cut-outs made thereat. One of said flanges accommodates propulsion reduction gear attachments while another flange makes the torsion box rear side. Note here that torsion box sides as-extended form the bottom lengthwise elements. Torsion box walls in fuel compartment area can be composed of sandwiched panels with cellular filler while torsion box bottom is composed by panel with larger height of cellular filler compared with that of said walls.

EFFECT: integrity of airframe critical parts at emergency.

2 cl, 8 dwg