A solution to the problem one person tying down the rotor blades of a helicopter when the rotor blades are too high to be reached by a person standing on the ground involves a rotor blade tie down having a flat structure of two adjacent layers attached along three sides and open on one side to facilitate the placement of an end of the rotor blade in an interior of the device. When pressurized water from the hot water heater reaches the desired temperature level at the fixture, the bypass valve closes and hot water is made available to the fixture. A local routing node includes a unit for passing signaling of communication between a base station and the gateway according to a protocol of the mobile communication system, for extracting and decapsulating bearer data transferred between the base station and the gateway, and for thereby obtaining and transferring user data and a unit for encapsulating and transferring user data. Events on different links are uncorrelated. A separate air duct, which forms an incoming-air flow, is provided to blow out incoming air underneath latent heat accumulator bodies by utilizing he Koanda effect, while air is sucked in parallel to the surface of the latent heat accumulator bodies.