Would an EMALS failure endanger British or French carriers?

Would Britain be in trouble if EMALS failed?

No. Britain's ski-jump carriers do not rely on EMALS, while France would have to adapt its less mature future-carrier design.

Britain's Queen Elizabeth-class carriers use short takeoff and vertical landing aircraft with ski jumps, so their operation does not depend on EMALS. Project Ark Royal and related catapult-conversion concepts are described as design studies without a promised conversion programme. France would face a larger problem because its future carrier plans depend on catapults. The French design is judged early enough in this discussion that an alternative could probably still be incorporated if necessary.