Computational fluid dynamics studies of horizontal flight for a vertical take off and landing reusable launch vehicle are underway at the Japanese Aerospace Exploration Agency (JAXA).

The studies are in preparation for a flight test programme for the Reusable Vehicle Test demonstrator (RVT), which would likely be called RVT-4.

The flight campaigns RVT-1, -2 and -3, organised by JAXA’s Institute of Space and Astronautical Science, came to an end in 2003.


The RVT is a 4m (13ft) high, cone shaped vehicle with landing struts and a liquid hydrogen, liquid oxygen engine. This demonstrator project has a team of ten researchers and an annual budget of less than $1 million a year.

“It will cost tens of millions of dollars to pay for the next flight programme. We are aiming for flight demonstrations every two years,” says the project’s leader and JAXA’s Institute of Space and Astronautical Science’s research division’s space systems professor Yoshifumi Inatani, speaking on 18 October at the 2nd International Symposium for Personal Spaceflight, held in Las Cruces, New Mexico.

RVT-4 could involve horizontal flight where the vehicle transitions from vertical thrust to forward thrust. This transition and necessary horizontal flight control is the subject of the studies.

Wind tunnel testing has taken place at ISAS’s Sagamihara facility’s wind tunnels, of which there are four. They are the low speed, transonic, supersonic and hypersonic tunnels.

Much of the RVT team’s work is focused on vehicle reusability and reliability with goals of highly reliable sub-systems and high levels of fault tolerance at the system level.