I’m sure it’s been this way for years, but:
1). Aircraft type evaluation tool lists “Fixed costs total”, which should really just be “Total Cost”… which is the sum of variable and fixed costs for the flight.
2). Within the “Corporate Finance” menu, viewing the loan details of an aircraft’s contract, “Principal/Week” implies that interest is not included. I feel that “Weekly Payment” is more accurate, which is the sum of principal and interest.
Hi Pilatus, thanks a lot for your input! I get far too few corrections for the English localisation, which is odd, since I am not a native speaker and these financial terms in particular are very tricky to translate 
Regarding your first example: I think the label “fixed costs” is correct here as the number does not include variable costs per pax. All costs incurred by simply operating the flight, no matter how well or not it gets booked, are technically “fixed”. Does that make sense?
And the second one: Any other native speakers who could weigh in here? This is one of those subtleties that are near impossible for me to judge
English can be a pain, thank you for hearing me out.
Perhaps others have input on the first example as well. Especially on a financial table which consists of fixed and variable costs, the addition of the word ‘fixed’ is not necessary and leads to confusion. Perhaps “total cost per flight” or “cost per flight” is better to indicate the sum of all costs associated with the flight.
On the finance side. Principle is referring to the Balance without interest. Some places will use the term instalment or weekly instalment to refer to the payment which includes the main loan and all the extras like interest.
Installment: A set amount you pay on a regular schedule, like every month.
Principal: The portion of your payment that lowers the actual payoff balance of the vehicle.
Interest: The portion that goes directly to the lender as profit based on your Annual Percentage Rate (APR).
Principal-Only Payment: An extra, separate payment you can make to lower your balance faster without paying extra interest
