Launch Vehicles Under Development: Vulcan Centaur and New Glenn

Here we are with a new chapter of the Launch Vehicles Under Development column! In the previous chapter, the lead actors were two Super-Heavy rockets: SLS and Starship; today, the rockets are still big, but they are “just” heavy-lift launch vehicles (in the LV NASA Classification). These are ULA’s Vulcan Centaur and Blue Origin’s New Glenn.

Let’s go into the details to discover all the differences and, more importantly, similarities between Vulcan Centaur and New Glenn.

ULA’s Vulcan Centaur

Vulcan Centaur is a rocket developed by United Launch Alliance (ULA) in the factory in Decatur, Alabama. The focus in the design of Vulcan Centaur is to give a cheaper access to space, compared to Atlas V and Delta IV, with higher performance and greater affordability always assuring unmatched reliability and precision. Moreover, the goal is to have 20 to 25 launches per year. The US military invested in this project, expecting to launch national security satellites with Vulcan Centaur; ULA, in fact, is competing with SpaceX for the contract of 35 missions over the next five years.

The rocket has multiple variants with the possibility to have a different number of boosters and different configurations for the fairing: in fact, Vulcan Centaur can have 0, 2, 4, or 6 boosters and a standard faring with 15.5m-length or a large fairing with 21.3m-length. These characteristics are discussed in the Flight Configuration Key, which will follow shortly:

$VC6L$

where:
VC: Vulcan Centaur
6 = the number of solid rocket boosters (0, 2, 4, 6)
L = Payload fairing length (Standard or Large)

Vulcan’s Stages

The rocket is divided into two stages with an Interstage Adapter between them; the first stage is powered by two engines, the BE-4, that we will encounter again with New Glenn, as they are both designed and manufactured by Blue Origin. The presence of boosters increase the thrust created at liftoff. Those boosters, the GEM-63XL, are designed by Northrop Grumman.

The second stage, called “Centaur V”, instead, is powered by two Aerojet Rocketdyne’s RL10C engines, which are their first 3D printed engines. The Aerojet Rocketdyne engines are a link between Vulcan and its predecessors Atlas V and Delta IV. These had the second stage powered by RL10, itself a predecessor of the RL10C. In this regard, Aerojet Rocketdyne has reported a record order of RL10C engines in April 2022: 116 engines! However, this order is justified with the contract with Amazon for the launch of 38 missions with Vulcan Centaur for the Kuiper Project. The Kuiper Project will be a broadband constellation with more than 3000 satellites in orbit; Amazon signed off on ir with Arianespace, ULA, and, obviously, with Blue Origin.

We will review all the rockets’ numerical specifications in the tables below, so as to compare the two launchers together.

Maiden Flight

The first flight of Vulcan Centaur has been delayed by about two years. One of the reasons is the delays in development and testing of the BE-4 engine. However, ULA said that the maiden flight will be in the first half of 2023. On board Vulcan will have Peregrine-1, a lunar lander developed by Astrobotic Technology; its configuration will be VC2S.

Check here for all the updates on the Vulcan Centaur maiden flight and on future missions.

Blue Origin’s New Glenn

New Glenn is the first orbital rocket developed by Blue Origin, the company founded by Jeff Bezos in 2000. Blue Origin also has a suborbital program for space tourism with the rocket New Shepard. New Glenn is named after John Glenn, the first american astronaut to orbit around Earth, in 1962.

Blue Origin designed New Glenn to decrease costs and, so, increase access; in fact, they have developed a first stage that is reusable for a minimum of 25 missions. Therefore, New Glenn will be competitive for civil, commercial, and national security operators. The project also includes the possibility to carry people, in addition to payload, on Earth’s orbit and beyond.

New Glenn’s Stages

As said before, New Glenn is a two stage rocket: the first stage is powered, as Vulcan, by BE-4 engines. In this case, however, it is powered by 7 engines. BE-4 are very powerful, releasing more than twice the max thrust of a single Falcon 9’s Merlin. The second stage, instead, powered by 2 re-ignitable BE-3U, is designed for highly energetic missions to LEO, MEO, GEO and beyond.

The first stage, as we mentioned, is reusable with minimal maintenance and inspection between flights, thanks to: the introduction of wing-like strakes to create lift and cross-range; four fins used for attitude adjustments; and landing gear to support and secure the first stage during landing.

The aim for Blue Origin is to have a fully reusable rocket; in fact, the Project Jarvis has been created to develop a reusable second stage.

The capacity of New Glenn is very high, capable of lifting 45 MT to LEO and 13 MT to GTO, because the fairing with its 7m-diameter is twice the payload volume of other existing launch vehicles.

Maiden Flight

The New Glenn’s maiden flight is scheduled for 2023. Blue Origin has still not released a more precise date. The date will depend, as with Vulcan, on the developing and testing of the engines. However, the launch pad is already defined; they will launch from the Launch Complex LC-36 at Cape Canaveral. Otherwise, it is not clear if the landing will occur on a platform or on the land. The first idea was to land the rocket on a ship 180m-long and 25m-across; the ship was named Jacklyn after Jeff Bezos’s mother. However, this idea has more or less been abandoned.

Check here for all the updates on the New Glenn maiden flight and on future missions.

Final Comparison

In this last paragraph, we will put together the numerical specifications of the launch vehicles under development in order to compare the two. Not to rank them based on merit, but to relate the different specifications between rockets that are similar at an initial glance.

General

The two rockets are quite different, New Glenn is taller and has a larger fairing envelop; furthermore, the reusability of the first stage make the New Glenn cheaper.

	Vulcan Centaur	New Glenn
Height	62 ÷ 67 m	98 m
Max Diameter	5.4 m	7 m
Gross Lift-off Weight	547 T
Maiden Flight	H1 2023 – Peregrine 1	2023
Reusable?	No	Partially reusable

The capability to LEO of New Glenn, as said before, is higher since the fairing envelope is bigger; but, for the capability to GTO, the larger configuration of Vulcan Centaur, the VC6L, provides a slightly greater capability.

Capability	VC0S	VC2S	VC4S	VC6S	VC6L	New Glenn
To LEO	9.2 MT	16.3 MT	21.6 MT	25.8 MT	26.9 MT	45 MT
To GTO	3.5 MT	8.4 MT	11.7 MT	14.5 MT	15.3 MT	13 MT

First Stage

Both Vulcan and New Glenn have the same engine for the first stage; however, since Vulcan has the possibility to have 2 to 6 boosters, it needs less engines than New Glenn.

First Stage	Vulcan Centaur	New Glenn – “GS1”
Height		57.5 m
Engine Name	BE-4	BE-4
Engine Contractor	Blue Origin	Blue Origin
Engine Number	2	7
Oxidizer / Fuel	CH4/LOX	CH4/LOX
Max Thrust	4.9 MN	17.1 MN
Specific Impulse

Second Stage

For the second stage, Vulcan uses two engines produced by Aerojet Rocketdyne, while New Glenn has two self-produced engines, with a max thrust seven time bigger than Vulcan Centaur.

Second Stage	Vulcan Centaur – “Centaur V”	New Glenn – “GS2”
Height		39.5 m
Engine Name	RL-10C	BE-3U
Engine Contractor	Aerojet Rocketdyne	Blue Origin
Engine Number	2	2
Oxidizer / Fuel	LH2/LOX	LH2/LOX
Max Thrust	212 kN	1400 kN
Specific Impulse	460.9 s