During the late 1970s and early
1980s, many people sought to be able to fly affordably. As a result, many
aviation authorities set up definitions of lightweight, slow-flying
aeroplanes that could be subject to minimum regulation. The resulting
aeroplanes are commonly called ultralight or microlight,
although the weight and speed limits are rarely the same between any two
countries.
The safety regulations used to
approve microlights vary between countries, the strictest being the United
Kingdom, Italy,
Sweden and Germany, while they are almost non-existent in France and the United
States. The disparity between regulations is a major barrier to international trade and overflight, as is the
fact that these regulations are invariably sub-ICAO, which means
that they are not internationally recognised.
In most affluent countries,
microlights or ultralights now account for about 20% of the civil aircraft
fleet.
Aeroprakt A22 Foxbat 3-Axis ultralight
United States
Main article: Ultralight aircraft (United
States)
The USA FAA's definition of an ultralight
is significantly different from that in most other countries and can lead to
some confusion when discussing the topic. The governing regulation in the United
States is FAR 103, which specifies a powered
"ultralight" as a single seat vehicle of less than 5 US gallons (19
L) fuel capacity, empty weight of less than 254 pounds (115 kg), a top speed
of 55 knots (102 km/h), a maximum stall
speed not exceeding 24 knots (45 km/h), and are only allowed to fly
during daylight hours and over unpopulated areas. An unpowered
"ultralight" (hang-gliders, ect.) is limited to a weight of 115 lb
(52 kg). Weight allowances can be made for two-seat trainers, amphibious
landing gear, and ballistic parachute systems.
In 2004 the FAA introduced the
"Light-Sport Aircraft" category, which closely resembles other
countries' ultralight categories.
Ikarus C42, a German ultralight
In the United States no license
or training is required by law for ultralights, but training is highly
advisable. For light-sport aircraft a sport pilot certificate is required,
which is similar in requirements to other countries' ultralight license.
Ultralight aviation is
represented by the United States Ultralight Association (USUA), which
represents the US portion of the sport to the world through its affiliation with
the FAI.
Canada
Main article: Ultralight aircraft (Canada)
Europe
The definition of a microlight
according to the Joint Aviation Authorities document JAR-1
is an aeroplane having no more than two seats, maximum stall speed (VS0)
of 35 knots (65 km/h) CAS, and a maximum take-off mass of no more than:
- 300 kg for a
landplane, single seater; or
- 450 kg for a
landplane, two-seater; or
- 330 kg for an
amphibian or floatplane, single seater; or
- 495 kg for an
amphibian or floatplane, two-seater, provided that a microlight capable
of operating as both a floatplane and a landplane falls below both MTOM
limits, as appropriate.
Foot-launched aircraft are
excluded from this definition.
Australia
Main article: Recreational Aviation Australia
In Australia a
"Sport/Recreational aircraft" must have:
- a maximum all-up
weight (MAUW) of 544 kg or 1,200 lb or less;
- a stalling speed under
45 knots in landing configuration and
- a maximum of two
seats.
New Zealand
In New Zealand microlight
aircraft are separated into two classes, basically single and two seat
aircraft. All microlights are required to have a prescribed endurance testing
period when they are first flown, and all microlights must have a minimum set
of instrumentation to show airspeed (except powered parachutes), altitude and
magnetic heading.
NZ Class 1
Single seat aircraft with a
design gross weight of 544 kg (1,200 lb) (landplanes) or 579 kg (1,275 lb)
(seaplanes or amphibians), or less, and a stall speed in the landing
configuration of 45 knots or less. Requires aircraft registration, and annual
condition inspections, but does not require a permit to fly.
NZ Class 2
Two seat aircraft with a design
gross weight of 544 kg (landplanes) or 614 kg (seaplanes or amphibians), or
less, and a stall speed of 45 knots or less in the landing configuration.
Must meet minimum type acceptance standards which may be foreign standards
which have been deemed acceptable, or via a temporary permit to fly and
flight testing regime. Requires aircraft registration, annual condition
inspections, and a current permit to fly.
Types of aircraft
Quicksilver MXII
While ultralight-type planes date
back to the early 1900s (such as the Santos-Dumont Demoiselle), there have
been three generations of modern, fixed-wing ultralight aircraft designs,
which are generally classed by the type of structure.
The first generation of modern
ultralights were actually hang gliders with small engines added to them, for
self-launching. The wings on these were braced by wires, and steered by
shifting the pilot's weight under the wing.
The second generation ultralights
began to arrive in the mid-1970s. These were designed as powered aircraft, but
still used wire bracing and usually single-surface wings. Most of these have
"2-Axis" control systems, operated by stick or yoke, which control
the elevators (pitch) and the rudder (yaw) -- there are no ailerons, so may
be no direct control of banking (roll). A few 2-Axis designs use spoilers on
the top of the wings, and pedals for rudder control. Examples of 2-Axis
ultralights are the "Pterodactyl" and the "Quicksilver
MX".
The third generation ultralights,
arriving in the early 1980s, have strut-braced wings and airframe structure.
Nearly all use 3-Axis control systems, as used on standard airplanes, and
these are the most popular. Third generation designs include the
"T-Bird," "Kolb" and "Challenger" families.
There are several types of
aircraft which qualify as ultralights, but which do not have fixed-wing
designs. These include:
- Weight shift - while the first generation ultralights were
also controlled by weight shift, most of the current weight shift
ultralights use a hang glider-style wing, below which is suspended a
three wheeled pod which carries the engine and aviators. These aircraft
are controlled by pushing against a horizontal bar in roughly the same
way as a hang glider pilot flies. Trikes generally have impressive climb
rates and are ideal for rough field operation, but are slower than other
types of fixed-wing ultralights.
- Gyroplane - rotary wing with cart mounted engine (see autogyro),
a gyrocopter is different from a helicopter in that the rotating wing is
not powered, the engine provides forward thrust and the airflow through
the rotary blades causes them to autorotate
or "spin up" to create lift. Most of these use a design based
on the Bensen Gyrocopter.
- Helicopter - there are a number of single-seat and two-place
helicopters which fall under the microlight categories in countries such
as New Zealand. However, few helicopter designs fall within the USAs
more restrictive ultralight category. One of these is "Mosquito."
- Hot air balloon - there are numerous ultralight hot air balloons in the US, and several more
have been built and flown in France and Australia in recent years. Some
ultralight hot air balloons are hopper
balloons, while others are regular hot air balloons that carry
passengers in a basket.
Safety
A foot-launched powered hang glider.
Historically, ultralights have
had a poor safety reputation. Most of the early designs were fragile or unstable,
and this resulted in a number of accidents. However, the reputation came
largely from rumor and distrust of the new type of aircraft.[citation needed]
As designs matured, pilot error
was shown to be the cause of the vast majority of incidents involving
ultralights. As a result, most countries now require an Ultralight Pilot's
license/certificate, often regulated by one or more officially-delegated pilots'
organizations. The United States does not have any such requirement, but
pilots advise training for anyone interested in flying ultralights. For this
purpose, the FAA permits instruction to be given in two-place versions of
ultralights.
The build quality and
airworthiness of ultralight aircraft (and homebuilt light-sport aircraft in the USA) now
equals that of Certified light aircraft [citation needed]. Some
types satisfy both sets of requirements and are available for registration to
either Ultralight or Certified status. When registered as an ultralight (or Experimental), the pilot is permitted to do
more of the simple maintenance tasks, resulting in a lower cost of operation,
although this comes at the cost of restrictions such as avoiding densely
populated urban areas, bad weather, or night. Many older pilots are willing
to trade these operational restrictions for a lower drain on their retirement
incomes, [citation needed] and as
a result many ultralights are now flown by experienced General
Aviation (GA) pilots or ex-commercial pilots. One other reason for this
increase in acceptance is that any pilot is "only one medical away from
being an ultralight pilot" -- a reference to the requirement that most
other pilots must pass periodic physical examinations, but not to fly
ultralights. These effects mean that the experience level of the average
ultralight pilot has risen and now probably equals, and may even exceed, that
of the average GA pilot. [citation needed]
The future
Weight Shift Ultralight ("Trike")
Ultralight/microlight aircraft
were once regarded as "flying clotheslines", since early aircraft
were typically completely open, wire, tube and rag aircraft – these aircraft
were seldom used for anything more than local area flying.
However, ultralights are rapidly
transforming into high performance aircraft, capable of very respectable
speed and range. In recent years there has been a dramatic rise in the number
of General Aviation pilots flying high performance
ultralights due to the cost benefits.
These aircraft are now often
referred to as recreational aircraft.
A rapidly growing area of the
class is scale-replica "warbirds", such as the offerings from Titan
Aircraft and Loehle Aircraft.
