Project of a 155 MM Forest Firefighting Projectile

Resumo

Thousands of square meters are burnt every year during fire season. Preventive measures have been proving to be insufficient and the capabilities of firefighting means are conditioned by rough terrain, low visibility conditions and the inability to operate with adverse weather conditions. The introduction of the proposed projected in this thesis aims to fill the void left by these constraints. This project gives continuity to the FIREND® project, which is the latest evolution of a concept idealized in 2005 that is being developed in a partnership between Academia Militar and Instituto Superior Técnico. The knowledge obtained from the literature review of patents, previous FIREND® projects and artillery manuals was complemented with the knowledge of ballistics and mechanical design to achieve a solid development of a 155mm electronic detonated projectile. The projectile concept is based on micro gas generators that, upon actuation, produce high pressure values within the projectile vessel, therefore ejecting the transported cargo. The tridimensional capabilities of SolidWorks® software were used for drawing and computation of weight, volume, inertia moments of the projectile components and the available cargo capacity. This data is crucial for the project to assure its compatibility with the howitzers and tabular firing tables that are in use by the Portuguese Army Artillery. The result of the present Master Thesis is the project of a firefighting projectile that complies with the conventional 155mm artillery projectiles in terms of weight, external dimensions (length and diameter)and center of mass, which is capable of transporting 7,5 dm3 of cargo and that it has the capability to act on an area with approximately 75 m2.