I am very sorry that you are frustrated.
But the campaign is designed for people who already have certain piloting skills. And the fact that there are missions in the campaign in which the helicopter is used in extreme regimes is part of the gameplay and the mission's plan is just that, this is not a bug. With careful piloting, all missions are passable without loss of RPM and turning off the generators. The author always monitors the performance of the campaign and quickly fixes bugs that have arisen.
Specifically, in the mission of Radio Hunt, everything works as it should, carefully monitor the messages. Beacons also work in all missions.
Sincerely.