There is a problem with the air endurance rules that has just turned up. To keep things as simple as possible, the endurance rules deal only with distance, not with time. At cruise throttle setting, all other things being equal, you burn one nautical mile for each nautical mile of distance you cover. But what if you travel at less than cruise speed? Sea Harrier FA.2 Altitude Cruise Full Mil Reheat V/Low: 450 (1.9) 650 (2.7) -- Med: 450 (1.9) 583 (2.4) -- High: 450 (1.9) 516 (2.2) -- Cruise Range: 600 nm Drop Tank Desc. 190 IGal drop tank Fuel Wt. 690 kg Range Add. 180 nm Example: A Sea Harrier with two 190 IGal drop tanks has a cruise range of 960 nm, and cruises at 450 kts. At that speed, it takes it 2.12 hours to cover that distance. But what if it flies at 350 knots? Its time aloft becomes 2.7 hours. In fact, according to the existing rules, you could cruise at minimum speed (20% of max) and stay aloft for an unrealistically long time. A Sea Harrier at High altitude has a max speed of 516 knots. Twenty percent of this is 103 knots. At that speed, the plane can stay aloft for over nine hours! Some people have tried to use this discrepancy to have CAP “loiter” for unrealistically long periods. A fixed-wing aircraft can indeed stay aloft at 20% of its max speed, but that is its stalling speed, the lowest possible speed before the wing stops working. It is true that at lower power settings, you burn less fuel, but at the same time drag starts to assert itself. Fuel efficiency, in terms of fuel burned per nm covered, is lousy, and other restrictions, like limits on maneuvering, make this unusable in the game. In rule 3.3.2 (page 3-6 of the 4.1 rules), in the second paragraph from the bottom, change “Aircraft must move at least 20% of their maximum speed...” to “Aircraft must move at least 50% of their speed at Full Military throttle...” This means that the Sea Harrier could fly at 258 knots, at High altitude, giving it an endurance of 3.7 hours while it “loiters.” This is a gross oversimplification of the lift/drag/power relationship, but we’re trying to keep it simple here. Also, please note that the rule also changes “maximum speed” to “full military.” This excludes afterburner, which is an aerodynamically unnatural act, and would drive mini-mum speed above cruise for most high-performance aircraft. This is an official change, and will be incorporated in the next printing of the rules. BT Back to The Naval Sitrep # 25 Table of Contents Back to Naval Sitrep List of Issues Back to MagWeb Master Magazine List © Copyright 2003 by Larry Bond and Clash of Arms. This article appears in MagWeb.com (Magazine Web) on the Internet World Wide Web. Other military history and related articles are available at http://www.magweb.com