Space

The Reagan Administration made its first move in the direction of a private ELV industry more than two years ago, when commercial rights to key launchers were transferred to private industry. Transpace Carriers. Acquired the MDC Delta in. an interim arrangement, Martin Marietta the Titan 34D and General Dynamics the Atlas-Centaur. Until the Mission 51-L disaster occurred prospects were bleak – subsidised Shuttle and Ariane flights catered for most of the market’s needs.

With the Shuttle absent for two years and available for few commercial· payloads in the following years, Ariane solidly committed, China’s Long March untried and Russia’s Proton questionable given the possibility of unauthorized technology acquisition, the US private ELV industry has a clear opportunity to get off the ground. Some US sources have questioned the long-term viability of the industry, given the transient nature of the situation. Much will depend on the growth in Ariane’s capacity and the level of utilization of Shuttle payload capacity in the 1990s.

At this instant, Martin Marietta appears to be in the lead with pending orders for 23 Titan 34D-7s issued by the US DoD and with the largest number of customer enquiries. Transpace had run into difficulties with NASA in the last quarter of 1986, following protracted negotiations over the terms of the privatization agreement, with NASA subsequently declining to enter a commercial agreement with the Delta manufacturer McDonnell Douglas.

Germany Proposes Saenger Spaceplane As Alternative to Hotel

While the radical British Aerospace Hotol captured much of the limelight in 1986 (refer p116 Nov 86 AA), Germany has moved ahead with its own proposal for a post-shuttle generation launch vehicle.

In July last year German officials approached the European Space Agency (ESA) with a request that studies of Hotol be conducted in parallel with the studies of the MesserschmittBolkow-Blohm (MBB) Saenger. The Seanger is a two-stage vehicle conceptually similar to some of the rejected early shuttle configurations using a winged reusable first stage and winged reusable orbiter.

The first stage is an air-breathing hypersonic aircraft powered by a bank of turbo ramjets, a robust technology as evidenced by the Foxbat family. With an empty weight around 150t and gross weight about the 350t mark, the vehicle would use any facility able to support 747 size aircraft. A runway length of 8,200ft for a takeoff speed in the 280kt range is envisaged. After takeoff, this vehicle, with a piggyback orbiter, designated Horus, would climb above commercial air traffic and accelerate toward Mach 6 (1,800m/s – although Mach 10 is apparently under consideration it would involve major powerplant development) hypersonic cruise. At an altitude of 110,000ft (35km) the second stage would ignite its 500kN class rocket powerplant, separate and accelerate to 8560,:n/s at an 80km altitude with a 280sec burn.

This would be the first phase of a minimum energy (Hohmann) ascent trajectory which would carry the orbiter up to an apogee of 400km where it would inject itself into orbit with a short 4-second burn. Having completed the launch manoeuvre the first stage vehicle would cruise back to its launch site and carry out a conventional runway landing MBB. who have paid for most of the project studies with company funds, see the first stage vehicle as having a lot of commonality with a TransAtmospheric Vehicle (TAV) aerospace plane and hypersonic commercial transport with 200 seat capacity.

The orbiter vehicle has a· gross weight of about 55 tons, of which 40 tons is LH2/LOX (liquid hydrogen/oxygen) fuel. A crew of two is carried with payload options of four tons of cargo or twelve passengers and two tons of cargo. MBB envisage a design life of 100 flights for the first stage and airframe/systems of the orbiter, with an orbiter powerplant life of 50 flights. The orbiter will be skinned with an advanced lightweight metallic sandwich using titanium and new alloys. ·

An option proposed is the use of an expendable second stage which would carry up to 1 0 tons of payload to a low orbit. Mission profiles envisaged by MBB include space station replenishment and crew exchange, servicing of low and polar orbit platforms, low orbit passenger and freight transport.

While the Saenger vehicle cannot offer the performance of the projected BA Hotol its supporters point out that the vehicle involves far fewer technological risks than Hotol with its hybrid air-breathing rocket powerplants; which could conceivably cause difficulties in a development programme. It promises to be an interesting contest.

And Closer to Home…

A planned ‘Space Research Options . for Australia’ seminar hosted by the Institution of Engineers Australia and the US-based Space Test Irie scheduled for last September and covering practical engineering aspects of space-based equipment design was cancelled.

Speakers to have taken part included several specialists with experience encompassing the Apollo, Skylab and Shuttle programmes. The seminar failed to attract enough interest and was subsequently cancelled, advised the IEAust. Needless to say, it is most disappointing to see an event that is aimed at the practical aspects of getting into space not receiving attention. We can only hope this won’t discourage any organizations with plans for other such events.

On a much brighter note, the South Australian Government has entered a joint venture with British Aerospace Australia involving the development, design and manufacture of medium-sized satellite earth stations. Designated SA-Satcom, the two-phase programme will lead up to a pilot link in 1987-88. The eventual objective is to provide low-cost communications for State Government departments while also providing a technology base for a commercially marketable product.