Despite the more than $40 billion in fighter purchases up for grabs soon, governments are concerned about the long-term health of the industrial base for combat aircraft.

Contractors have started to engage in a spate of hotly contested fighter competitions around the world, with decisions pending in the next 24 months.

But in the U.S., the three major military airframers - Lockeed Martin, Boeing and Northrop Grumman - are participating in a far-reaching "war game," a Pentagon-backed study intended to assess the status of the future industrial base and secure capabilities required for future fighters and bombers.

One question is whether a second source is needed for the Lockheed Martin F-35 Joint Strike Fighter. Boeing has briefed the Pentagon about how it could build the F-35, but JSF program officials say the cost is prohibitive and runs counter to the original affordability strategy underpinning the program.

In Europe, the four Eurofighter partner nations are struggling to strike a deal for the third Typhoon production tranche, while France is pushing for further consolidation of the region's combat aircraft sector. Russia is also on the brink of consolidating its fighter manufacturers.

Present fighter competitions - notionally totalling in excess of 400 aircraft - are being given an added edge by the pending arrival of the F-35, and the risk of closure of some of the competitor type production lines if additional orders are not secured in the next few years.

The Pentagon study will consider what technologies, skills and resources are in place for the next generation of strike aircraft beyond the F-35, including potentially an evolution to what some contractors refer to as a sixth-generation capability. This could include unmanned systems eligible for the U.S. Air Force's next-generation bomber as well as the Navy's F/A-XX. Northrop Grumman is vying with a Lockheed Martin/Boeing team for the bomber work.

After the industrial consolidations in the 1990s, the U.S. was left with two manned fighter production lines. A bomber hasn't been built since the 1990s.

Wall St. analysts will participate in the Pentagon study as neutral brokers.

Already, Boeing and Northrop Grumman are trading jabs. Chris Chadwick, president of Boeing Military Aircraft, says, "Does Northrop want to get back into the game? Sure." Boeing's future as a mainstay airframer of tactical aircraft is in question as the F/A-18 and F-15 production lines are expected to wind down in the next decade and the company has yet to secure new military work.