This article guides readers through the steps required to determine the ultralight aircraft longest flight. The article describes the factors affecting an aircraft's range, and ends by detailing the maximum theoretical flight range for a powered ultralight aircraft.
An ultralight aircraft is one of the newest ways to enjoy the experience of flight. Ultralights can be both powered (equipped with an engine) or unpowered (similar to gliders). For people who are interested in the design of ultralight aircraft, planning to choose an ultralight for personal use, or even simply saw one fly overhead, one of the most common questions is "How far can one of those things fly?!" Some aspiring pilots may even consider using an ultralight for traveling. To discover what the ultralight aircraft longest flight can make is, read on.
Basic Specifications: Set by Law
In the United States, the Federal Aviation Administration sets the rules regarding air traffic, including ultralight aircraft. The exact rules for ultralight aircraft are established in the Federal Aviation Regulations, or FARs. FAR part 103 is the section regarding ultralights.
Although the FAA does not specify a maximum range for ultralights, limits are set regarding the maximum fuel capacity and speed for the ultralight aircraft; this allows a general estimate to be made regarding the longest flight for an ultralight. This section of the FARs specifies that powered ultralights must have a maximum, full-power level flight speed of 55 knots. In addition, the ultralight must have a fuel capacity of no more than 5 gallons. So how far can an ultralight fly?
Final Range: It Depends!
The final range of an ultralight aircraft will depend heavily on the fuel consumption of the engine, and the prevalent winds at altitude. The average fuel consumption of a Rotax 2-stroke aviation engine, which is a commonly used ultralight powerplant, is between 5.5 and 6 gallons per hour. This means that an ultralight with the largest possible fuel tank - 5 gallons - could only fly for just under an hour before it ran out of fuel. If that same ultralight was capable of the maximum legal speed of 55 knots in still air (calm winds), this gives the ultralight a range of around 50 nautical miles - or around 58 statute miles.
However, the prevailing winds in an area will heavily affect the range of the ultralight. A 20-knot headwind reduces the range of the ultralight by nearly 50 percent. Likewise, a 20-knot tailwind would extend the range of the ultralight to somewhere around 75 to 80 statute miles.
As noted, the range of an ultralight aircraft is heavily dependent on winds and fuel consumption, both of which can be fickle. An ultralight pilot could depart in still air, expecting a 55 nautical mile range, and encounter an unforecast headwind which may cause him or her to fall short of their destination. Likewise, the powerplant will only use 6 gallons per hour under certain circumstances - changes in temperature and altitude may increase the fuel consumption heavily, decreasing the range.
Ultralights are not meant for long-distance travel, and attempting maximum-range travel could be very dangerous for an amateur pilot. Instead, ultralights should be used to enjoy the feeling of flight in a local area - perhaps even remaining within power-off gliding distance of a field at all times, since no fuel gauge is required on board.