Rocket Lab's Neutron slips to 2027 over voids in a carbon-fibre dome
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What Via Satellite reports: Rocket Lab has pushed the debut of its Neutron rocket to next year, 2027, after finding air pockets between the layers of carbon fibre in a propellant dome made on an automated fibre placement machine. This follows a tank that ruptured in testing in January; Rocket Lab said then that the rupture exposed a manufacturing defect in a tank hand-laid by a contractor. The article does not name the contractor or say the hand-laying caused the defect, and the account is Rocket Lab's own. No launch date beyond 2027 was given. Why it matters for materials: voids between plies are a classic composite-manufacturing defect. They generally lower interlaminar strength and are hard to see without inspection, so they are caught by process control and non-destructive testing, not by the material datasheet. Moving from hand layup to automated placement changes which defects show up; it does not remove them. Our take: we have only a trade-press account of Rocket Lab's statements, with no void size, fraction or location, and no independent inspection. What our data can add is how directional the material is: our CFRP page lists a unidirectional IM7/HexPly 8552 laminate at 2724 MPa tensile strength along the fibres but only 64 MPa across them (Hexcel data, 25 °C, dry). That is in-plane transverse tension, not interlaminar strength, which our archive does not list, but it shows how much weaker the resin side is, and voids between plies mainly hurt resin-dominated properties such as interlaminar strength. What we would watch: whether Rocket Lab publishes inspection findings or a revised process, and how the dome is made after the change. How would you qualify a large composite tank?