Abstract: A spring element for connecting two components, the two components having substantially the same direction of extension, where one component is fixed relative to the other component, with the latter component having angle of rotation mobility relative to the fixed component. In the component extension direction, a T-shaped sectional piece is provided having a base section extending in the component extension direction and a section extending substantially perpendicularly from the base section. The section extending from the base section has a connecting device for connecting this section to the component with angle of rotation mobility. The base section has torsional flexibility and includes a connnecting device at each end for connecting the base section to the fixed component. The connecting devices for connecting the base section to the fixed component are limited to both ends of the base section.

Abstract: A rotor, in particular a helicopter rotor, whereby the movement of the pitch angle of the rotor blade relative to a rotor hub is provided either by a blade neck with torsional flexibility disposed between a blade root and a blade wing or by a blade connection on a rotor hub arm with torsional flexibility. The pitch angle control for the blade is provided by a steering rod coupled to a torsionally stiff blade control casing extending coaxially without making contact along the blade neck or the rotor hub arm up to the blade wing or to the blade root. The control casing is supported on the blade root or rotor hub by at least one brace, which brace, in the longitudinal direction of the blade, has a T-shape. The vertical section of the T-shape is coupled to the blade control casing and the T-base is coupled with torsional flexibility to the blade root or the rotor hub arm, whereby the connection to the base is limited to both of the extremities of the base.

Abstract: A rotor, especially for rotary wing aircraft, has a rotor hub (1) with one r more torsionally stiff rotor hub arms (1.1) projecting radially outwardly. A rotor blade (2) having a blade root (2.1), a blade wing section (2.3), and a torsionally flexible blade neck (2.2) is attached by bolts (3) to each rotor hub arm (1.1). A torsionally rigid blade angle control sleeve (5) extends without contact along each blade neck (2.2) and is rigidly connected at its radially outer end to the blade wing section (2.3) and is movably connected at the radially inner end to the blade root (2.1). In order to isolate the blade control from any blade flapping movements, and to reduce the distance between the flapping hinge point and the rotor hub (1), the rotor hub arm (1.1) is flat in a direction perpendicular to the blade rotation plane and is more flexible to blade flapping movements than the blade neck (2.2) is. The blade root (2.1) is in the form of a yoke or fork for attachment to the rotor hub arm (1.

Abstract: A rotor blade, for example for a rotary wing aircraft, has a wing section d a root section interconnected by a neck section surrounded by a blade angle adjustment sleeve which is stiff against torque moments for transmitting blade angle adjustment movements through the sleeve to the wing section. The trailing edge of the sleeve is provided with a gap which extends, at least partially, alongside the rear edge of the neck section for visually inspecting the neck section inside the sleeve even when the root section is connected to a rotor hub. A reflecting mirror may be used for inspecting all sides of the neck section through the gap.

Abstract: A rotor blade has a neck section which connects the blade proper to a rotor ead at the blade root. The neck section is flexible against bending in the lead-lag direction and in the flapping direction. A carrier member is located alongside or inside the neck section but spaced from the neck section. The carrier member is resistant against bending at least in the lead-lag direction or in the flapping direction. The carrier member is rigidly connected at its one end to the blade proper. A layer of a damping material is operatively interposed between the carrier member and the neck section, preferably at the blade root end of the neck section, whereby blade vibrations preferably in the lead-lag direction are damped and substantially prevented from entering into the rotor head.