[Code of Federal Regulations]

[Title 46, Volume 4]

[Revised as of October 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 46CFR108.235]



[Page 131]

 

                            TITLE 46_SHIPPING



                  (This book contains parts 90 to 139)

 

   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)

 

PART 108_DESIGN AND EQUIPMENT--Table of Contents

 

                 Subpart B_Construction and Arrangement

 

Sec.  108.235  Construction.



    (a) Each helicopter deck must be designed to accommodate the 

loadings (static and dynamic) imposed by operation and stowage of 

helicopters intended to use the facility as well as environmental 

loadings (wind, wave, water, snow, etc.) anticipated for the unit.

    (b) The adequacy of each helicopter deck for the loadings required 

in paragraph (a) of this section must be shown by design calculations. 

Where the placement of a load affects the suitability of a structural 

member, the load must be evaluated in the most unfavorable position for 

each member.

    (c) The analysis required in paragraph (b) of this section must be 

based on the dead load of the structure, existing stresses in the deck 

when it is an integral part of a unit's structure, and each of the 

following loading conditions:

    (1) Uniform distributed loading. A loading of 2kg/m\2\ (42 lb/ft\2\) 

applied to the helicopter deck area.

    (2) Helicopter landing impact loading. The limit load established by 

the limit drop test in 14 CFR 29.725, or a load of not less than 75 

percent of the helicopter maximum weight taken on a square area of 

0.3x0.3 m (1 ft.x1 ft.) under each main landing gear unit applied 

anywhere on the helicopter deck area.

    (3) Stowed helicopter loading. The helicopter maximum weight plus 

inertial forces from the helicopter due to anticipated unit motions, and 

applicable environmental loadings including wind loads.

    (d) The landing area of each helicopter facility must--

    (1) Have a non-skid surface;

    (2) Have drainage facilities that prevent the collection of liquids 

and prevent liquids from spreading to or falling on other parts of the 

unit;

    (3) Have recessed tie-down points; and

    (4) Be free of projections, except that landing lights or other 

projections may be installed around the periphery of the landing deck 

provided they do not interfere with landing and take-off operations.

    (e) The unprotected perimeter of each helicopter facility must have 

a safety net at least 1.5 meters (4.92 ft.) wide. The outer edge of the 

net must not extend more than 15 centimeters (6 in.) above the surface 

of the deck.

    (f) Each helicopter facility must have both a main and an emergency 

access/egress route located as far apart from each other as practicable.