In addition, Lockheed has also indicated that it will offer manufacture of major components, maintenance work and engine assembly of the F-35 to Japanese firms.

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And the Volt is likely to fare even better on maintenance since it only uses the engine about 40% of the time.

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However, the existence of two different engine designs increases the likelihood of something going wrong either with the basic design or with maintenance procedures because additional complexity is introduced into the fleet.

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