What is LSA?

In recent years, lightweight small aircraft category called Light Sport Aircraft (LSA), which is inexpensive for two people, is spreading in Europe and the United States.

The LSA belongs to the category between Ultra Light Plane (ULP) and conventional small airplanes. The ULP has gained widespread globally because it is easier to get licenses than conventional small airplane and its operation costs are lower, but in the U.S. survey research was conducted to revise the ULP systems, because there are problems in terms of safety and operation. On the other hand, conventional small aircraft can operate widely as an aircraft and safety is secured, but it is hard to say that it is general as it is costly and expensive to airframe and maintenance costs, and it takes time and expense to get licenses, so there was a need for a new aircraft category that can further enhance the primer aircraft at a low price while ensuring safety and further limiting the performance and flight method compared to small aircraft. As a result, in the United States, targeting small aircraft that is larger, safer and cheaper than ULP, the pilot is given the systems of Sport Pilot License, and the basis of the primary category is now to be set. Also in Europe, They established the category of aircraft and pilot in the form of extending the UL category. In the United States, 6528 LSAs were registered by 2010, since LSA category was regulated in 2005. LSAs are also spreading in China, Korea, India, Australia, and Southeast Asia.

On the other hand, in Japan, The ULP is out of the aircraft category and has been used limitedly by flight permission, but there are many accidents caused by illegal flight that does not comply with illegal remodeling or flight permission because there is no inspection systems, so further development is difficult from the point of safety. There is a limit to managing LSA which is a higher performance aircraft under flight permission, and we think that institutionalization like overseas is an urgent task.

In Europe, there is UL (Ultra Light) as a category close to LSA, and LSA and UL seem to be on sale on the same aircraft. The UL is less restrictive than LSA, it is more performance-oriented, such as retractable landing gear is possible. Currently, in these categories, the propulsion devices are becoming more electrified, and not only the engine of conventional aircraft → motor replacement but also the aircraft registered and sold as electric aircraft have appeared. The biggest problem for electric aircraft is short endurance, which is proportional to the battery capacity, but due to the dramatic improvement in battery technology, aircraft with a cruising time exceeding 1 hour are appearing. The advantages of the electric motor are low noise, zero emissions, simplification of the mechanism around the prime mover, and so on, but above all, the operating cost is overwhelmingly cheaper than the internal combustion engine, and it has quite excellent qualities as an entry aircraft.

Our laboratory conducts research aiming to introduce this LSA category to Japan through designing, prototyping and evaluation of aircraft that conform to LSA, surveying domestic / overseas operations and legal development.



 ULP,軽飛行機とのLSAの比較          LSA登録機数の予想

Definition of LSA

Standard specification for aircraft that conform to the LSA category are not based on the International Civil Aviation Organization (ICAO) applicable to large aircraft, but mainly on the American Society for Testing and Materials (ASTM). Due to this, manufacturing and inspection of the aircraft become dramatically cheaper and become a factor to accelerate the spread.

For example, the main definitions of the US LSA are as follows.

1)Aircraft restriction

・Maximum gross weight of 1,320 lbs (600kg) or less.

・Maximum airspeed of 120 knots CAS (222 km/h) or less.

・Seating for no more than 2 people (including the pilot).

・A single, reciprocating engine.

・A fixed pitched propeller (or ground-adjustable).

・A non-pressurized cabin.

・Fixed landing gear.

・Maximum stall speed of 45 knots CAS (83 km/h).

2)Operation restrictions

・Fly during the daytime using visual flight rules (VFR).

・Limited to personal sports, flight as recreation (however, practice flight is possible)

・Available for leasing of aircraft, sale.

・Obligation of aviation security equipment.

・Obligation of aviation insurance.

・Operation in accordance with aviation law.