Today we’ll be demonstrating the manufacturing process for the carbon fiber, upper and lower fuselage for the Zone 5 CLEAVER, a Cargo Launch Expendable Air Vehicle with Extended Range platform.

We will be showing the fabrication using the Hawthorn Composites Advantage that includes dry fiber fabrics and vacuum assisted resin transfer molding (VARTM) with low-cost infusion grade epoxy resin.

We begin with the lower fuselage.

First 0, +/- 60 degree triaxial carbon fabric from A&P Technology, called QISO, is cut to ply shapes using an automated table cutter.

The aluminum molds being used were precisely engineered to the final part OML, or outside mold line plus coefficient of thermal expansion (CTE) scale factor offset.

The next step is to place the carbon ply into the nose area of the fuselage mold first. For this layup we need a noodle made from hand forming 3 pieces of carbon fiber rope into a triangular shaped noodle. This noodle will help to eliminate resin rich corners in the sharp angular step in the fuselage. Then, 6 QISO plies are laid into the mold and finish trimmed to exact shape by hand and are held in place by a resin compatible tackifier spray.

The lay-up is completed by adding peel ply, flow media, a custom vacuum bag that is placed over the completed lay-up and sealed to the mold; And then another vacuum bag is attached to the mold as a failsafe to the 1^st bag. Vacuum is then pulled inside the vacuum bags, which ensures the plies receive 1 atmosphere of compaction and enables VARTM infusion of the epoxy resin. A proper engineered resin flow strategy and a very low overall vacuum leak rate is critical to the resultant part quality.

The completed lay-up and mold are then transferred into an industrial oven, plumed for infusion, and pre-heated to 178 degrees Fahrenheit while still under active vacuum to both preheat the mold for infusion, and to ensure the fabric is completely dry.

Once drying is complete, the epoxy is VARTM infused into the dry fiber layup and once infusion is complete, the valves are closed and the composite part is cured using the resin manufacturers recommendations.

After the cure is complete and the mold is still at an elevated temperature, the cured composite fuselage is de-molded by technicians, inspected, and then sent to the finishing area.

At the finish area, the composite fuselage is manually trimmed while leaving excess material so the fuselage can be finished trimmed and drilled on a five axis machining center.

Next is the upper fuselage nose.

The main difference in the lay-up of the upper fuselage nose, is that a step lip or flange is added that allows the upper and lower fuselage to be re-joined during the final assembly process.

Here you can see a technician laying up the step lip of the modified upper fuselage mold. A noodle is used on this upper fuselage nose to ensure the area of the joggle joint is not resin rich.

Similar to the lower fuselage, 6 plies of QISO are laid up by hand using the same tackifier spray, followed by peel ply, flow media and a vacuum bags.

Once infusion and cure are complete, the upper fuselage is de-molded and sent to the finishing area to receive the initial trimming and sanding before five axis machining.

Now that the CLEAVER’s carbon fiber fuselage is complete it can be sent to the customer.

Applying the Hawthorn Advantage, including the use of hand applied, dry carbon fabric, combined with VARTM infused epoxy resin, allowed Hawthorn Composites to meet Zone 5’s aggressive price and quality targets and the final solution achieved Zone 5’s expectations for reduced assembly and integration times.

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