TOPER Tool (Boeing 737NG) - Updates in Nikola Jovanovic Support Forum Posted Thursday at 11:35 AM · Report reply 6 hours ago, jonesm35205 said: Hello Nikola, I just bought TOPER CALCULATOR TOOL - B737 NEXT GENERATION (TAKEOFF PERFORMANCE CALCULATOR) and I cannot get it to work properly. I fly 737 800 all the time, but it will give Flex Temp of 70 with anything u put in their for the 700, 800 and 900. The only only aircraft it gives me a different Flex Temp is the 600. Something is not right. I have updated it with the new Airac Cycle of 1901 but SimMarket has me downloading most likely a old version, but I still wouldn't think that would cause the app to give a better result by updating it. I need to know what I need to do to get this fixed. Or get my money back. I look forward to hearing back from you. Thanks, Mark Jones Dear Mark, please try using: shorter runway lower flap settings higher take-off weights You should be getting temperatures that are less than 70deg.