Reading every think that all of you wrote, I think my speech could be:
"Hello everyone, is the captain speaking.... due to technical reasons we are unable to proceed to our destination at this time, so we need to return to the airport and the estimate time to arrive will be in about 15 minutes. The company will provide more informations for all of you and about the continuation of your trip upon landing. We appologize about this inconvenience, thank you for your attention."