NBAA IFR reserves
NBAA IFR reserves are the fuel allowance that business jet manufacturers assume when publishing range figures: enough to fly to an alternate airport 200 nautical miles away (100 nm for smaller aircraft), hold for 30 minutes and land with a margin, on top of the fuel for the trip itself. Because the assumption is standardised, brochure ranges from different manufacturers are comparable, but they still represent a best case with a light passenger load, no headwind and ideal routing. In practice an operator's flight planning will often demand more reserve for weather or remote alternates, which is why the achievable range on a real day can be 10–15% less than the number in the brochure.