Roller shutter cutter LS3
|Roller shutter cutter LS3|
4th February 1976
|Number of pieces:||
The LS3 is a single-seat glider of the "old" racing class , with a 15 m wingspan and flap. It was designed by Wolf Lemke and manufactured by Rolladen Schneider Flugzeugbau GmbH in Egelsbach near Frankfurt. The first flight was on February 4, 1976. Unusual on this aircraft are the wings with continuous flaperons ( ailerons over the entire length of the wing are operated simultaneously as a flap ) and "single trapezoidal plan".
All controls (landing gear, flaps and trim) are located on the left side. The spring-loaded chassis can be retracted and extended very easily and is braked with the feet. Since the flap lever is guided directly on the push rod for the airbrakes, the flaps are automatically pushed into the landing position (+10) when the airbrakes are extended, which significantly reduces the risk of incorrect operation.
The LS3 was never really successful in competitions. The aerodynamics of the aircraft only got under control after various improvements (ventilation of the flap gap and cover parts for the wing-fuselage transition). The heavy weight of the LS3 (rudder mass balance) also bothered many pilots, which gave it the nickname “LS lead”. In addition, the wing profile of the LS3 with a relative thickness of 17% is quite sensitive to mosquitoes and rain.
The objective performance is convincing, however: The LS3 has shown very good glide ratios (> 40) and excellent high-speed flight performance in several measurements . Despite its heavy weight, the aircraft climbs extremely well in the thermal. In the meantime, mosquito cleaners have been introduced, which compensate for the problems of the wing profile when dirty. What is less well known is that in the original version all oars are automatically connected during assembly. The robust aircraft has extremely effective airbrakes that give the pilot reserves when landing in unfamiliar terrain. All in all, the LS3 is an inexpensive glider with very good flight characteristics and performance.
In addition to the LS3, the LS3a, which is about 30 kg lighter, was built from 1978 onwards, which was later marketed in a 17-m version with attachable surfaces. With this lighter LS3a, which has now been built again with separate ailerons and flaps, the discussion about weight should end. With the same maximum take-off weight, the water ballast also increased the leeway . Recently, variants with winglets were also seen. In addition, an LS3 with automatic flap was built based on the principle of the Mü 28 .
|design type||Surfaces: GRP foam sandwich, hull: GRP|
|Wing profile||Wortmann FX-67-K-170 (modified)|
|class||Racing class||Racing class||18 meter class|
|span||15 m||15 m||17 m|
|Wing area||10.5 m²||10.5 m²||11.22 m²|
|Masses and payload|
|Empty mass||270 kg||243 kg||255 kg|
|Water ballast||150 kg||150 kg||-|
|Max. Takeoff mass||472 kg||472 kg||370 kg|
|Wing loading||approx. 35-45 kg / m²||approx. 33-45 kg / m²||approx. 30-33 kg / m²|
|Demolition speed||64 km / h||62 km / h||60 km / h|
|Slightest sinking||0.62 m / s||0.60 m / s||0.55 m / s|
- Georg Brütting : The history of the LS aircraft. DG Flugzeugbau GmbH, archived from the original on December 15, 2010 ; accessed on March 16, 2019 .
- Type certification of the LS series - EASA-TCDS-A.095 (PDF; 409 kB)
- Richard H. Johnson, A FLIGHT TEST EVALUATION OF THE LS-3 ( Memento from February 6, 2005 in the Internet Archive ) (PDF file; 966 kB)
- Richard H. Johnson, A FLIGHT TEST EVALUATION OF THE LS-3A ( Memento from February 6, 2005 in the Internet Archive ) (PDF file; 628 kB)
- Richard H. Johnson, A FLIGHT TEST EVALUATION OF THE LS-3/17 ( Memento from February 6, 2005 in the Internet Archive ) (PDF file; 1.1 MB)
- ↑ Idaflieg report books ( Memento from June 14, 2011 in the Internet Archive )