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Ultralight aircraft

 
Sci-Tech Dictionary: ultralight aircraft
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(′əl·trə′līt ′er′kraft)

(aerospace engineering) An extremely lightweight, single-seat aircraft with low flight speed, power, and fuel capacity, used for sport or recreation.

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Sci-Tech Encyclopedia: Ultralight aircraft
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A lightweight, single-seat aircraft with low flight speed and power, used for sport or recreation. Ultralights evolved from hang gliders. See also Glider.

There have been tremendous variety of ultralight airframe configurations and control systems. Airframe types include powered weight-shift hang gliders, flying wings, canard designs, antique biplane replicas, and traditional, monoplane structures with conventional tail designs. Control systems can be either weight-shift systems, two-axis controls, or conventional three-axis controls. In weight-shift designs pilots must shift their weight, using a movable seat, to change the attitude. Two-axis designs use controls to the elevator and rudder only; there are no ailerons. Modern designs use three-axis control systems; weight-shift and two-axis control systems are no longer in production. Three-axis controls resemble those of a standard airplane and include either ailerons or spoilerons (spoiler-type systems used to make turns). Some more sophisticated ultralights are equipped with wing flaps, used to steepen approach profiles and to land at very slow airspeeds. See also Airframe; Flight controls.

Typically, ultralight airframes are made of aircraft-grade aluminum tubes covered with Dacron sailcloth. Areas of stress concentration are reinforced with double-sleeving or solid aluminum components. Most ultralights are cable-braced and use aircraft-grade stainless steel cables with reinforced terminals. Wingspans average 30 ft (9 m), and glide ratios range from 7:1 to 10:1, depending primarily on gross weight and wing aspect ratio. See also Airfoil; Aspect ratio; Wing.

Ultralight engines are lightweight, two-stroke power plants with full-power values in the 28–35-hp (21–26-kW) range. They operate on a mixture of gasoline and oil, and most transmit power to the propeller via a reduction or belt drive, a simple transmission that enables the propeller to rotate at a lower, more efficient rate than the engine shaft. See also Airplane; Propeller (aircraft); Reciprocating aircraft engine.

Wikipedia: Ultralight aircraft (United States)
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Pterodactyl Ascender ultralight aircraft
An Ultraflight Lazair
Eipper Quicksilver

Ultralight aircraft in the United States are much smaller and lighter than ultralight aircraft in all other countries.

In the USA ultralights are classified as vehicles and not aircraft and are thus not required to be registered or for the pilot to have a pilot licence or certificate.[1][2]

Contents

US definition of "ultralight"

Regulation of ultralight aircraft in the United States is covered by the Code of Federal Regulations Title 14 (Federal Aviation Regulations) Part 103 or 14 CFR Part 103, which defines an "ultralight" as a vehicle that:

  • has only one seat[1][2]
  • Is used only for recreational or sport flying[1][2]
  • Does not have a U.S. or foreign airworthiness certificate[1]
  • If unpowered, weighs less than 155 pounds[1]
  • If powered:
    1. Weighs less than 254 pounds (115 kg) empty weight, excluding floats and safety devices[1]
    2. Has a maximum fuel capacity of 5 U.S. gallons (19 L);[2]
    3. Has a top speed of 55 knots (102 km/h; 63 mph) calibrated airspeed at full power in level flight[1]
    4. Has a power-off stall speed of 24 knots (45 km/h; 28 mph) calibrated airspeed or less[1]

Certification

  • Ultralight vehicles and their component parts and equipment are not required to meet the airworthiness certification standards specified for aircraft or to have certificates of airworthiness.[1]
  • Operators of ultralight vehicles are not required to meet any aeronautical knowledge, age, or experience requirements or to have airman or medical certificates.[1]
  • Ultralight vehicles are not required to be registered or to have registration markings.[1]

Operations

  • Ultralight vehicle cannot be flown except between the hours of sunrise and sunset.[1]
  • Ultralight vehicles may be operated during the twilight periods 30 minutes before official sunrise and 30 minutes after official sunset or, in Alaska, during the period of civil twilight as defined in the Air Almanac, if:
    1. The vehicle has an operating anti-collision light visible for at least 3 statute miles[1]
    2. The flight is only in uncontrolled airspace[1]

Ultralight vehicle cannot be flown over any congested area of a city, town, or settlement, or over any open air assembly of persons.[1]

Weight allowances can be made for two-seat trainers, amphibious landing gear, and ballistic parachute systems.[1]

In the United States, while no license or training is required by law for ultralights, training is highly advisable.[2]

References

  1. ^ a b c d e f g h i j k l m n o p Federal Aviation Administration (January 2007). "Title 14: Aeronautics and Space, Part 103 - Ultralight Vehicles". http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=550836984d4438af2f5c15d80dff5c99&rgn=div5&view=text&node=14:2.0.1.3.16&idno=14. Retrieved 2008-01-23. 
  2. ^ a b c d e United States Ultralight Association (2009). "Frequently asked Questions". http://www.usua.org/faq.htm. Retrieved 2009-08-16. 

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

 
 

 

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