Volanti Development Story – Part 2

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As already mentioned, being able to ‘mix and match’ different airframe elements is vital to satisfying different specific mission requirements. The base structural component is what we call the ‘wing-box’ which is effectively the central fuselage and inboard wing-roots including the main carry-through spar.

Modular Elements

The wing-box contains all the motor mounts, a fuel tank, and a dedicated avionics area. The base wing-box can be combined with different nose shapes that are essentially fairings around the payload. These nose-cones can be one of several off-the-shelf sizes we can make from existing tooling, or customised as needed. They accommodate different shapes and sizes of payload, from simple fixed cameras, to multispectral arrays and other specialised sensors.

Some examples of nose shape options. The length of the rear booms can also be adjusted to optimise for different weight and balance requirements.

Conventional take-off Cometa in the background, and VTOL version in the foreground. Airframe in the foreground has a removable nose fairing. The one in the background has a fixed nose with access hatch on top.

Another nose option, with modular payload shelves mounted on carbon rails so they can easily be swapped out.

In Production

To wrap things up, here are some notes about translating our extensive prototyping and testing to ongoing production.

All production tooling is either carbon or metal. Metal is used for small and shallow components where crisp/fine detailing is required. The hard and non-porous surface can be repeatedly polished and gives a clean release with virtually no mould deterioration. Carbon tools are more suitable to larger parts with deep curvature, and where thermal expansion considerations start to matter. We source our tooling resins from various suppliers and have an extensive history of experimentation to adjust tooling properties to suit the application. As always, the parts are almost exclusively made from prepreg carbon, with various moulding and curing techniques used, according to part characteristics.

We have perfected an effective closed-mould technique to make tubular and conical parts in a single-cure process. The extra material visible on the left forms a slip-joint that ties the top and bottom halves of the part together as one during cure.

Carbon mould for lower skin of wing-box. The mould includes all information necessary for downstream processes. For example, outlines for cut-outs and screw centre witness-marks are machined into the master plug/pattern. And the mould flanges contain guides for aligning the booms and spars.

Metal moulds for our off-the-shelf VTOL motor pods.

Assorted parts in production.

Since the airframe is modular and comes apart for packing into a compact transport case, we identified some great opportunities for making gains through innovative solutions for the various interfaces and joints. The outer wings unplug at roughly one-third span, near the root of the longitudinal booms. So an effective spar joining method had to be devised to transfer the bending moment and locate the outer wing securely. After testing various configurations of axial screws, transverse pins, and even magnets, we developed and optimised the T-Latch system that allows secure, tool-free assembly without needing access to the inside of the airframe, and leaving a flush surface on the wing.