Rocket Lab Neutron

Neutron

Function	Reusable orbital launcher
Manufacturer	Rocket Lab
Country of origin	United States
Size
Height	42.8 m 140.4 ft
Diameter	7 m 5 m
Mass	480,000 kg 1,060,000 lb
Associated rockets
Comparable	Falcon 9
Launch history
Status	In development
Launch sites	MARS (planned)
First flight	2024 (planned)
Payloads Payload to low Earth orbit Mass 13,000 kg 28,660 lb 15,000 kg 33,000 lb Payload to Moon Payload to Venus Mass 1,500 kg 3,300 lb Payload to Mars Mass 1,500 kg 3,300 lb
Stages information First stage Diameter 7 m 23 ft Powered by Archimedes (9) Maximum thrust 7,300 kN 1,640,000 lbf Specific impulse 320 s Propellant liquid methane liquid oxygen Second stage Height 11.5 m Diameter 5 m 16 ft Powered by Archimedes Vacuum (1) Maximum thrust 1,110 kN 200,000 lbf Propellant liquid methane liquid oxygen

Neutron is a medium-lift two-stage launch vehicle under development by Rocket Lab. Announced on 1 March 2021, the vehicle is being designed to be capable of delivering a payload of 13,000 kg (28,700 lb) to low Earth orbit in a partially reusable configuration, and will focus on the growing megaconstellation satellite delivery market. The vehicle is expected to be operational sometime in 2024. It uses LOX and liquid methane propellant on both stages of the vehicle.

Design

An earlier design of Neutron, featured at the initial unveil in March 2021, featured a rocket 40 m (130 ft) tall with a 4.5 m (15 ft)-diameter payload fairing. Rocket Lab stated that they intended for the first stage of the vehicle to be reusable, with landings planned on a floating landing platform downrange in the Atlantic Ocean.

On 2 December 2021, Rocket Lab unveiled a revised design for Neutron, featuring a tapered shape with a maximum diameter of 7 m (23 ft). Rocket Lab abandoned plans for landing Neutron on a floating platform, instead opting for a return-to-launch-site reusability profile. Instead of a conventional payload fairing that is jettisoned and recovered at sea, the fairing is integrated into the vehicle, and opens during stage separation to release the second stage and payload, and then closes before the first stage lands back on earth. The rocket features a unique interstage design where the second stage is "hung" from the first stage structure.

On the 22nd of September 2022, another revised design was unveiled at an investor day, with the first stage engine count increased from seven to nine, and the engine architecture changed from gas-generator to oxygen rich staged combustion. This was done primarily to allow for a lower turbine temperature, while maintaining the same specific impulse. The engine will run with a significantly lower chamber pressure than other similar engines, at the cost of some performance. They have also reduced the number of fairing segments from four to two.

On the 27th of July 2023, new concept art on the Rocket Lab website showed a further revised design, with a reduction in the number of payload fairing sections from 4 to 2, redesigned landing legs, and small changes to the overall shape of the rocket. The number of payload fairing sections was reduced in order to allow for simpler fairing opening mechanisms while the landing legs were redesigned in order to be optimized for landings on floating platforms, allowing for an increase in launch availability. The redesigned legs feature a folding mechanism similar to the SpaceX Falcon 9 landing legs.

Operations

On 28 February 2022, Rocket Lab announced that Neutron will launch from the Mid-Atlantic Regional Spaceport (MARS) within NASA's Wallops Flight Facility on the eastern coast of Virginia. It was also announced that the company will build a 250,000 square feet manufacturing and operations facility adjacent to the Wallops Flight Facility. Ground was broken for this facility on 11 April 2022. As of December 2021, Rocket Lab is planning for the first launch to take place no earlier than 2024. Test firing of Neutron's Archimedes engine will occur at NASA's Stennis Space Center in Hancock County, Mississippi.

Development timeline

Past and future development timeline of Neutron.

Date	Milestone	Status
Q2 2022	Moulds and tooling for Neutron completed	Completed
Q3 2022	Full-scale prototype hardware for Archimedes and Neutron being made	Completed
4 Nov 2022	Opening Archimedes test complex at NASA Stennis Space Center	Completed
Q4 2022	Hot firing Archimedes hardware for the first time	Completed
10 Jan 2023	Testing engine ignition on development hardware	Completed
Q1 2023	Test stand infrastructure completed for Neutron Stage 2 tank	Completed
8 Aug 2023	First Stage 2 build	Completed
4 Oct 2023	Stage two structural and cryogenic testing	Completed
NET 2023	Flight mechanisms test program	In Progress
NET 2023	Testing of all avionics and communications devices with critical onboard software and GNC algorithms	In progress
NET 2024	First Archimedes development engine build	In progress
NET 2024	First Archimedes engine hot fire	In progress
NET 2024	Stage 1 build	In progress
NET 2024	Stage 2 static fire	Not started
NET 2024	Stage 1 static fire	Not started
NET 2024	Launch complex 3 complete	In progress
NET 2024	Final integration	Not started
NET 2024	Wet dress rehearsal	Not started
NET 2024	Launch	Not started

Applications

Neutron can lift up to 15,000 kg (33,100 lb) while expended, 13,000 kg (28,700 lb) while landing the booster downrange and up to 8,000 kg (17,600 lb) with the first stage returning to the launch site. Rocket Lab forecasts Neutron will be able to launch 98% of all payloads launched through 2029. Rocket Lab also intends the design to be able to support constellation deployment, deep space missions, and eventually human spaceflight.

External links

• Neutron update on YouTube (2 December 2021)