Orbital Launch Vehicles Roadmap

Roadmap Overview

Orbital launch vehicles (LV) are internally propelled vehicles used to carry payloads from Earth’s surface to Earth orbit or beyond. They are powered by rocket engines that generate large amounts of thrust even in vacuum by means of expelling hot gas through a nozzle. The propellants burnt to generate that gas can be liquid or solid (or hybrids) and are stored inside the LV. Most launch vehicles are divided into stages to discard non-used structure and some of them are reusable.

This roadmap will be an L1 roadmap from the point of view of the LVs as a technology that enables the Human race to transport cargo from the surface of the Earth to outer space. ==

Roadmap model using OPM

The following Object Process Diagram describes the Orbital Launch Vehicle technology point of view for this roadmap. The main object of the diagram is the different launch vehicles, its decomposition into main components/subsystems like propulsion system, structures, tanks, avionics, payload adapters, and the main attributes. Finally, the processes in the lifecycle are described as the integration of the payloads and the actual launch.

Figures of merit

The table below shows a list of FOMs by which Orbital Launch Vehicles can be assessed. The first four (shown in bold) are used to assess the aircraft itself. They are very similar to the FOMs that are used to compare traditional aircraft which are propelled by fossil fuels, the big difference being that 2SEA is essentially emissions free during flight operations. The other rows represent subordinated FOMs that impact the performance and cost of solar electric aircraft but are provided as outputs (primary FOMs) from lower level roadmaps at level 3 or level 4, see the DSM above.

Figure of Merit	Units	Description
Payload to LEO	[Kg/Year]	Payload mass that can be put into a 500 Km circular low earth orbit for a specific launch vehicle every year. This takes into account the production rate of the rockets and, if applicable, the reusability.
Payload to mass Ratio	[Kg/Kg]	A performance FOM on how much mass is the payload of the total mass of the launch vehicle.
Cost per Kg	[USD/Kg]	The (advertised) cost of putting a Kg to the reference orbit when buying an entire rocket. Here it is not considered the effects of brokers and rideshares.
Reliability	[non-dimensional]	Rate of success over total launches per launch vehicle.