GENERAL INFORMATION 1. The requirements within this specification are the least restrictive of the National Procurement Specifications@ if the requirements are not the same. As minimum performance requirements related to the use of air-dropped@ expendable sonobuoys used in airborne ASW systems@ these requirements are those which all participating countries are encouraged to include in the detailed equipment specification when procuring their service approved equipments. 2. The parameters are provided for information and design guidance. Each nation initiating a new sonobuoy design is encouraged to reflect these parameters and shall on request@ provide to the other nations@ drawings and technical information relating to launcher interface and aircraft separation. 3. Where practicable@ new types should be made compatible with existing systems. Where it is not practicable@ the developing nation is invited to provide notification of deviation from the specification at an early date. 4. Nothing contained herein is intended to limit the development of an improved system to meet new service requirements. No amended issue of this specification shall make any less acceptable any existing sonobuoy or any sonobuoy already under development whose design is compatible with the issue of the specification in force at the time the development was commenced. 5. The provision of sample sonobuoys or replicas to enable the verification of launcher compatibility is encouraged. Launcher modifications@ or the provision of adaptive components@ shall be the responsibility of the nation possessing the launcher.