Neutron Hungry Hippo fairing completes qualification ahead of first launch

by Clarence Oxford
Los Angeles CA (SPX) Dec 09, 2025

Rocket Lab Corporation has qualified the captive Hungry Hippo fairing for its Neutron launch vehicle and is sending the structure to Virginia for integration ahead of the rocket's debut mission. The fairing halves remain attached to Neutron's first stage from liftoff through landing, rather than separating and being discarded or recovered at sea. In flight, the halves open to release the second stage and payload, then close again so the combined first stage and fairing can return to Earth as a single reusable element designed to support high-cadence missions for commercial, civil, and national security customers.

Neutron is described as a large carbon composite launch vehicle with a planned lift capacity of up to 13,000 kilograms, or about 33,000 pounds, to orbit. With the Hungry Hippo fairing design, structure, and operations now qualified, the hardware is being shipped to Rocket Lab's Launch Complex 3 at the Mid-Atlantic Regional Spaceport in Virginia for pre-launch test activities. Development of Neutron began in late 2021, and first launch is currently targeted for 2026, a schedule the company presents as placing Neutron among the faster commercially developed rockets in terms of timeline from program start to initial flight.

Rocket Lab Vice President - Neutron, Shaun D'Mello, said: "A rocket like Neutron has never been built before, and we're doing it at a pace and price point that's going to bring the innovation and competition needed in today's industry. Building, qualifying, and shipping Hungry Hippo is a fantastic marker of progress toward Neutron's first launch, and I'm proud of the team for their attention to detail and pulling off this significant milestone."

To qualify Hungry Hippo for flight, Rocket Lab ran a broad structural and systems test campaign intended to validate performance under the aerodynamic and mechanical loads expected during ascent and re-entry. The program combined full-scale testing of the fairing structure with a series of sub-component evaluations. These tests targeted factors such as load-bearing capability, actuation timing, and the interaction between the fairing, the rocket's guidance and control systems, and aerodynamic control surfaces.

Structural qualification work included applying 275,000 pounds of force across the carbon composite fairing to replicate the load regime at Max Q, when aerodynamic pressure on the vehicle peaks. The company also tested fairing actuation under flight-like conditions, opening and closing the fairing halves in 1.5 seconds, which is less than half the time allocated for successful stage separation and reorientation for descent. Additional exercises combined flight software, avionics, guidance, navigation and control systems, and other hardware to operate both canard and fairing actuators using the same avionics, harnessing, and mechanical hardware planned for flight.

Engineers introduced combined torque and bending loads at the canard hubs where Neutron's aerodynamic control surfaces attach to the fairing, with test levels pushed to 125 percent of the loads expected across all phases of flight. The campaign also verified that Hungry Hippo can tolerate handling loads across the vehicle's operational lifecycle, from integration of the second stage inside the fairing through complete vehicle assembly and mating to the launch mount. These handling tests extended through simulated recovery of Neutron after landing on the company's barge, named Return On Investment.

Once in Virginia, Hungry Hippo will be mated to Neutron's first stage in its final flight configuration. Rocket Lab plans additional pre-launch checks at Launch Complex 3, including static fire tests and a Wet Dress Rehearsal that will run the integrated vehicle through a full launch countdown sequence with propellant loading. These steps are intended to verify the performance of the fairing and first stage as a combined reusable system before Neutron's first mission.