BURKHART GROB has flown its Strato 2C high-altitude research aircraft successfully for the first time, in an hour-long test flight on 31 March.

The Strato 2C, the largest all-composite aircraft in the world, took off from Grob's Mindelheim site in Bavaria with former NASA test pilot Einar Enevoldson and Hans-Ludwig Meyer at the controls. After landing at Memmingberg, the crew described the aircraft's performance and handling as "excellent" and "trouble-free".

The company is still struggling to get the project's Government sponsor, the Federal Ministry of Research and Technology, to cover a DM30 million ($20 million) budget over-run to fund avionics and testing. A decision on this additional money had been expected in January, following the freezing of Government funding for the programme in June 1994 - leaving Grob DM10 million short of the DM72 million the ministry had promised to pay towards the DM93 million programme.

Grob says that the ministry is now "slowly" paying off this last tranche of the original funding. Grob, however, has meanwhile been forced to fund the two-and-a-half-year-old programme itself.

The Strato 2C is to be a one-off aircraft for use by the German Aerospace Research Establishment. The aircraft will be used to transport two pilots and two researchers into the upper stratosphere to carry out atmospheric and meteorological research, Earth observation or telecommunications work. The manufacturer says that it is having preliminary discussions with other unspecified commercial customers, but has not yet begun to market the aircraft for military applications.

The 24m-long aircraft has a wingspan of 56.5m and a maximum take off weight of 13.35t. It can carry a full crew complement and 1t of cargo, at 59,000ft (18,000m) for 48h on a single tank of fuel and can be operated for 8h at 78,700ft.

With the air density at these altitudes only some 3.5% of that at sea-level, Grob - with partner IABG - has developed a compound propulsion system which uses compound turbochargers to supply sea-level pressure air to the Teledyne Continental Voyager TSIOL-550 piston engines, maintaining a 300kW power output up to 24km altitude.

Source: Flight International