Write me a Tableau calculated field to do a moving hourly sum

I have airport data where each row is a departure flight showing its departure date, departure time, number of seats on the flight and the airport the flight is departing from. I wish to create a new column called "Rolling Hour Seats" I need to sum the seats of all flights departing in the next hour for each flight and airport. I'm guessing i need to use a "{fixed [orig] : " to separate the Airports (Orig). For example, a flight has a departure time of 9:10am on the 2/04/2018 at airport AAA; i want to sum the seats of all the flights departing AAA from 9:10am on the 2/04/2018 to 10:09am on the 2/04/2018 (exactly 60 minutes from and including the departure time of the flight in question) I want to do this without using a window calc I also want to use this calculation to determine two factors, shown in the excel file attached I have attached two files: 1. "Peak Hour Data" - the input data 2. "Peak hour Data - Example Calc" - shows the two calculations that need to be done for each flight, as well as the three outputs i wish to create in a table like the one in the document. I have also attached a photo showing the calculation to get the Datetime