ALH is a multi-role, multi-mission, twin-engine Helicopter. There are two versions namely a skid version in the 4.5 ton All up weight (AUW) class and wheel version in the 5.5 ton AUW class (Fig.1).

Cockpit frame is of single piece construction using Carbon/Kevlar prepreg. Cabin structure consists of composite side frames, side shells and roof structure. The sliding door structure is made of composite Carbon/Kevlar prepregs.

The empennage consisting of Vertical fin, Horizontal stabilizer and End plates are of composite construction using Kevlar, carbon and glass.

Main Rotor Blade is made out of glass and carbon composites while the Main Rotor Hub is of carbon composite. Kevlar and Glass composites are used in Tail rotor blades.

Composites are used extensively in ALH. The primary components which are made of composites are Main Rotor blades, Tail Rotor blades, Tail boom, Horizontal stabilizer, Fin , and Side frames. Various structural elements of ALH Airframe and Empennage are indicated in figures 2 and 3.

All the structural components have been validated by Finite element analysis using NASTRAN FE package and extensive ground testing at room temperature and elevated temperature wherever relevant. Figures 4 & 5 show test set ups for tail boom and fuselage

Utilization of advanced composite materials in primary structures and also in secondary structures has made ALH lighter by 25%. Number of parts count involved in fabrication of a component is significantly reduced. It was also possible to tailor the stiffness in the desired direction by the use of composites in the main and tail rotor blades. Other advantages of composites are improved surface finish and ease of repair in case of any damage.