SCOPE OF REQUIREMENTS

The Defence Standard includes within its scope, requirements and recommendations which arise from the operational function of Service Rotorcraft. It covers the following main categories of requirements:

The comfort and safety of the crew, guidance being given in such matters as the placing of controls and seats, the pilot's view and other allied subjects.

The basic considerations of design, strength and stiffness which are intended to ensure that the rotorcraft can carry out its duties safely and with an acceptably low risk of structural failure.

The aerodynamic and flying qualities of the rotorcraft.

The installation of engines, of fuel and oil systems and of the various other rotorcraft services.

The reliability and maintainability of the rotorcraft in order to ensure efficient operation and a reasonable service life.

The flight tests to be made by the contractor prior to delivery, for acceptance trials, of a new type or converted rotorcraft to an Experimental Establishment.

Reference Pages contain a list of publications which give useful amplification or explanation of the requirements and recommendations of a Chapter and its Leaflets or which promulgate additional requirements or information of which the designer should be aware. In addition to listing applicable Volume 1 Leaflets (see para 2.3 above), Reference Pages in this Volume will also include references to other publications (e.g., DEF STANS, DERA/RAE (Ex) Reports) which contain useful information applicable to rotorcraft only, together with publications from Volume 1 Reference Pages which may apply wholly or partly to rotorcraft.

* Formerly called Appendices in AvP970 Volume 3

APPLICABILITY OF THE REQUIREMENTS

The requirements given in the Chapters of Volume 2 of this Defence Standard apply when they are specifieidn Ministry of Defence Contracts for the new design and conversion of rotorcraft, and are intended to ampli@ the requirements contained in the Rotorcraft Specifications. In the event of any conflict between the requirements of an Rotorcraft Specification and those contained in this Defence Standard, the requirements in the Rotorcraft Specification shall take precedence.

Derogation from the requirements of the Chapters (indicated by the words "shall" or "must") is not open to the designer without formal agreement in writing from the MOD Rotorcraft Project Director.

Information and recommended practices amplifLing the Chapter requirements are given in the Leaflets* immediately following the Chapter, and also in a number of Leaflets of Volume 1 of this Standard. The Volume 1 Leaflets applicable are listed on the Reference Pages given at the end of each Chapter (see para 3.2 below). (These Volume 1 Leaflets have in general been written for aeroplanes and hence in some cases may not be wholly applicable to rotorcraft).

Leaflet contents are not mandatory except where for special reasons the Rotorcraft Specification calls up a particular Leafleto r part thereof Designers are expected, however, to consult the Leaflets and to incorporate their provisions in their designs unless, in the designer's opinion, there are good reasons for not doinsgo