Rocket Lab completes Neutron’s Hungry Hippo fairing tests

At Rocket Lab’s facility in Wallops, Virginia, the two halves of Neutron’s Hungry Hippo fairing are back in a hangar, waiting for the rocket’s interstage. The company says the fairing has completed all required testing, including opening and closing in flight-like conditions, and has received its thermal protection, control surfaces and avionics.

The hardware is designed to stay attached to Neutron’s first stage instead of falling away. Its halves open during flight to deploy the second stage. Rocket Lab says that approach removes the need for recovery vessels and the refurbishment required when a fairing reaches the ocean after splashdown. It targets a recurring task around launch operations without asking a ship to retrieve the hardware.

Neutron is a 43-meter partially reusable, medium-lift rocket. Its first stage uses nine Archimedes engines powered by methane (CH4) and liquid oxygen (LOX), a propellant combination called methalox, for a stated liftoff thrust of 6,450 kilonewtons. Rocket Lab says the vehicle can carry at least 13,000 kg to low-Earth orbit in a reusable configuration, and claims a capacity of 1,500 kg to Mars and Venus. The upper stage hangs inside the interstage, the section joining the stages, so its tanks do not carry the main flight loads and can be built lighter.

The first Neutron is targeted to launch by the end of this year from Launch Complex 3 at the Mid-Atlantic Regional Spaceport on Wallops Island. The site, completed in 2025, includes a 30-foot launch mount weighing over 700 tons and propellant storage for liquid oxygen, liquefied natural gas and liquid nitrogen. Neutron’s first stage is designed to land on a specialized barge downrange or return to the launch site, but Rocket Lab does not plan to recover any stage on the debut; that flight will focus on data collection.

Concretely, the near-term change is a new Rocket Lab vehicle aimed at satellite constellations, national-security missions and planetary exploration, with the fairing design potentially reducing recovery work if it performs as intended. The company has also been selected to develop and test communications systems for the U.S. Space Force’s Space Data Network, including an on-orbit demonstration with a Photon satellite. The over 400 hot-fire tests and completed fairing campaign mark development milestones ahead of the first flight, while its performance and recovery claims remain company targets rather than results from a completed Neutron mission.