The cracks found in the ageing Space Shuttle's engine could be the tip of the iceberg. NASA needs to face up to finding a replacement

It is not yet clear how serious are the hairline cracks discovered in the propellant lines of Space Shuttle main engines and whether they will delay future launches substantially, but they serve to illustrate the challenges facing the USA's once-transcendent space programme.

NASA spends too much money on space operations and too little on research and development. The International Space Station (ISS) may be nearing the end of its expensive assembly phase, but - in spacecraft terms - the Space Shuttle is entering old age and becoming increasingly costly to operate, even on the reduced number of ISS and science flights now planned.

NASA faces the divergent challenges of having to reduce the Shuttle's operating costs while improving its safety because it has no alternative way to carry crews to and from the ISS. It desperately needs to replace the Shuttle and is spending billions of dollars to develop new reusable launch vehicle (RLV) technology under the Space Launch Initiative (SLI). But an operational second-generation RLV will take billions more in taxpayers' money to develop and will almost certainly not be ready for another 10 years.

Ostensibly, the SLI will develop technology that will make the US launch industry more competitive. In reality, it is a lifeline for NASA's budget. Reducing launch costs is the only way to cut the agency's spending on space operations. And, in reality, developing a second-generation RLV could actually hurt the US launch industry's competitiveness by diverting R&D funding from improving the efficiency of expendable launch vehicles.

But NASA cannot send crews into space on expendable boosters - or so it believes. So it plans to spend billions meeting its own needs, rather than those of the industry it is supposed to serve. Its role as a space vehicle operator continues to eclipse its role as an incubator of technology. And while it spends its budget developing a second-generation RLV for its own needs, it delays critical decisions on extending the service life of the Space Shuttle.

NASA needs to make decisions now about how the Shuttle can be upgraded or replaced - not in 2006 as planned. And whatever happens, the Shuttle's service life will almost certainly have to be extended. The work needs to start now, before another Challenger-like disaster - or, more likely, before a growing catalogue of age-related defects and delays render the once-magnificent vehicle almost impossible to operate.

Build it...then sell it?

In the 1960s, Boeing bet on developing the 747 and then opted not to take on Europe with a Concorde rival. The subsonic widebody proved the right horse, with orders to date for 1,350 aircraft, compared to 14 Concordes. Almost 40 years on, roles are reversed, with Europe going fat and efficient with the A380 and Boeing mulling the need for speed.

The stakes for Boeing today are as high as they were in 1965 when Pan Am's Juan Trippe proposed the idea for a 747, challenging Bill Allen: "If you build it, I'll buy it." The Sonic Cruiser has the potential for shifting the paradigm in air transport, which, if realised, will ensure Boeing a dominant position for years. Failure's price would be a decade of lost development and relegation to a poor second behind Airbus.

The alternative to Sonic Cruiser is a conventional successor to the 757/767, which offers no break from the cost death-spiral of direct competition with Airbus. Boeing already has much ground to make up, having spent the 1990s studying and producing derivative after derivative of older designs, not all sales successes.

Airbus, having amassed a healthy backlog of A320, A330 and A340 orders at Boeing's expense, is not ready to concede ground and has a new 250-seater warming to counter any conventional challenge.

The decision facing Boeing is not easy and, unlike in 1965, there is no Trippe to force the issue. There is instead disagreement among airlines Boeing is confiding in. These are mainly Asia-Pacific carriers with very long routes wanting to cut travel time, but not at any price. There are also airlines just as happy with more of the same, but at even lower operating costs.

Furthermore, no airlines appear willing post-11 September to put cash up front against the promise of technology tomorrow. If Boeing really wants to rewrite the rule book it may have to start with its own preconditions for a new product launch and take a 747-size gamble that if it builds Sonic Cruiser, airlines will buy it.

Source: Flight International