Davening on plane and sefirat ha omer

Question

I am travelling on Wednesday to Australia. Leaving Atlanta at 5:50 pm, then departing Los Angeles at 11 pm. When I land in Australia it will be 8 am on Friday morning. When should I daven and when should I count the omer? On the return, it is a little less problematin because I leave Sunday morning and return to Atlanta Sunday evening. All of these are local times. The flights are very long. Thanks, Jim