Design of a hoistable helicopter platform for 60m yacht

Abstract

Aesthetic and geometrical constraints are undersigning the key problems in a full certification of a new helideck on a commercial yacht. The complexity it is also governed by the “linkage” that has to be done between the two different operational industries, yacht and aircraft.

Each “flight-capable” vessel is certified for operations with specific helicopter. Before a vessel is certified for a particular helicopter, the entire landing area must pass through a brief structural analysis, to ensure that the decks structure will safely support the operations of the helicopter.

Nowadays it can be found just one example which successfully accomplishes a fully certification for its landing area, the AIR, 81m Motor Yacht. Guidance for landing area design considerations are given in UK Civil Aviation Authority Paper 2004/02, included in the MCA’s, LY2 rules, and the structural safety is governed by Lloyd’s Register SSC Rules.

Hereby the requirement of the research is to design a foldable helideck, creating an aesthetically “link” between the helideck and yacht. The vessel is a 60 m motor yacht; the chosen helicopter is an EC 120, carrying 4 passengers and one pilot.

The work presents a brief structural design, direct FEM analysis and theoretical calculations, and mainly mechanical design. The theoretical and FEM calculations carried out showed a good agreement in using aluminum extrusions in construction of a helideck. The analysis carried out determines the resulting stresses on the helicopter deck structure imposed by the helicopter operations during worst emergency landing condition. The calculated stresses are in safe parameters compared to permissible values imposed by rules. The foldable helideck is composed from 5 main parts (one fix, and 4 foldable). The motion between the helidecks movable parts is imposed by hydraulic pistons.

For a full certification of the landing area, furthermore is mandatory to consider environmental effects-involving CFD analysis-and intact and minor damage (vessel less than 85 m) stability test.