The European project to develop a space jet for fare-paying passengers is still very much alive, says EADS Astrium.
The plane, which would make short hops above the atmosphere, was announced in 2007 and then almost immediately put on hold because of the global downturn.
But Astrium, Europe's largest space company, says internal development work continues and it will spend a further 10m euros (£9m) on the concept in 2011.
"We keep the investment going," said Astrium CEO François Auque.
"We continue to mature the concept, maintaining the minimum team, in order that when we find the relevant partnership we are ready and have progressed sufficiently," he told reporters on Wednesday at the company's rocket manufacturing facility at Les Mureaux just north of Paris.
The Astrium vehicle would be about the size of a business jet and would take off from a standard runway, using normal aircraft engines to climb to about 12km. It would then ignite a liquid oxygen-methane rocket to push the vehicle to about 100km.
At this altitude, the five passengers onboard could experience a few minutes of weightlessness before strapping themselves back in their seats for the return flight to the ground.
Astrium has done considerable work already on the Romeo rocket engine that would power the climb to space, and wind tunnel testing has proven the aerodynamic shape.
What is currently missing is the investment of a partner that would move the project from concept to production.
"As you know, we had discussions in the Gulf before there was a change in the financial situation. Now we have other discussions in other parts of the world and I'm quite optimistic," said Mr Auque.
Much more advanced is British billionaire Sir Richard Branson's Virgin Galactic project. This will use an American rocket plane developed by California's Scaled Composites company to send fare-paying passengers on sub-orbital trips.
Enterprise, as this rocket plane is known, is already built and conducting glide tests. It is expected Enterprise will fire its rocket motor and make demonstration flights above the atmosphere later this year.
Mr Auque was speaking at the annual New Year press conference of the European Aeronautic Defence and Space (EADS) group. In addition to owning the Astrium satellite and rocket concern, EADS also owns the airline manufacturer Airbus.