True, probably because Slingsby are a relatively small foreign company, and Textron Lycoming a large US company...
Still hooked on that foreign/domestic matter?

Perhaps the plane manufacture was the target for the lawsuit is because they're the one who holds the actual contract with the Air Force. The powerplant manufacture holds a contract with the plane manufacture, not the Air Force. If the fault is actually with the powerplant manufacture, it is the responsibility of the plane manufacture to sue them.
Here's an analogy: Say you have a house built. You get into your sparkling new whirlpool tub and turn it on. Lo and behold, you become electrocuted by defective manufacturing of the tub. You end up in the hospital and loose time at work, etc. Now, given that you have a contract with the home builder and not the whirlpool tub manufacture, who are you going to go after?
...the answer is obvious. Now back to the subject of the airplane. Going after the plane manufacture rather than the powerplant manufacture is the same concept, not some notion of American vs British, which is silly to me.

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