Some Studies on Design, Analysis and Manufacturing Aspects of Surface to Air Article Launching Canister

Surface to Air Guided Flight Articles are launched to intercept and destroy incoming enemy attacking fighter aircrafts, helicopters, unmanned aerial vehicles etc. These articles are generally stored in containers with slight positive pressure such that the articles are protected from external environment conditions to use them for longer periods. The containers used for storing and launching are generally called launch canisters. It is essential to design these launch canister to enable the articles to be loaded, connected electrically and mechanically with a facility to check the health of articles and also launch them remotely in the prescribed direction. The canister size must be as small as possible and it should also be light in weight to facilitate accommodating as many canisters as possible on a single mobile self propelled vehicle. The canister design must also cater for the movement of article during launching and protect its control surfaces which are generally folded and kept during storage, transportation. Applicable load conditions, design considerations, canister configuration and its manufacturing aspects etc are discussed. The clearances that are required to be considered between some parts of moving article and launch canister was studied. A metallic canister is designed with Aluminum alloy material sheets and for withstanding various transportation loads, stacking loads, acceleration and deceleration loads including loads due to articulation of launcher in azimuth and elevation angles. A novel construction is adopted in canister structure to withstand for internal pressure requirement. The launch canisters of smaller in cross section and more than four meter in length are manufactured using number of jigs and fixtures meeting stringent alignment requirements. Structural analysis is carried out for various applicable load cases using finite element modeling using ANSYS software. In addition, effect of impingement of plume in canister while the article is travelling inside is also studied using Computational Fluid Dynamics methods. Various types of hatch covers of launch canister studied for their advantages and disadvantages. The realized launch canisters have been successfully used in live firing thus validating their design adequacy.