My flying club sells introductory flights to the general public. How can I track the expenses of the flight against the revenue from selling the flight?

I can share some information that can help you with tracking expenses and revenue from selling introductory flights, @ESTreas.

You can set this flight as a product or a service item in QuickBooks Online (QBO). Make sure to set the sales price/rate and the cost of this flight. Once done, use that item in your invoices and sales receipts when there's a sale. Check out this article for more information on how to set up product and service items you buy and sell: Add product and service items to QuickBooks Online. 

Check out this article for detailed guidance on how and when to create a sales receipt and invoices in QBO:

• Create and send sales receipts in QuickBooks Online
• Create invoices in QuickBooks Online

Once done, you can run reports to check your expenses and revenue: Customize reports in QuickBooks Online.

Let me know if you have any other concerns with tracking your expenses and revenue. I'll do my best to help! Have a great rest of the day!