HFL Stratos

HFL Stratos
	; HFL Stratos 300 K
Type:	Microlight
Design country:	BR Germany
Manufacturer:	HFL light aircraft construction
First flight:	1985
Production time:	1985-1990
Number of pieces:	> 40

HFL Stratos is the name of a series of single-seat ultralight aircraft produced by the German HFL Leichtflugzeugbau GmbH in Lüneburg .

history

Georg Blech, Manfred Kleimann and Konrad Herz were involved in the construction of the B12 in the early 1970s as members of the Academic Aviation Group Berlin . After completing their studies, they founded HFL Leichtflugzeugbau GmbH with the support of the Ministry of Research and Technology . In 1984 the construction of the ultra-light aircraft "Stratos" was completed, which was exhibited at the Aero in Friedrichshafen in 1985 and in August of the same year in Oshkosh two awards from the Experimental Aircraft Association for design and constructionreceived. At the turn of the year 1985/1986 it was further developed into the Stratos II, which finally led to the Stratos 300 and 300 K (with spoilers ) in 1988 with the help of Ulrich Horn .

Ivo Amic won the German UL championships in 1990 with a Stratos 300.

construction

The cantilever wing monoplane with a rectangular wing was under the operational worthiness requirements for ultralight aircraft DAeC developed (BFU, Issue 10/84). The vertical stabilizers of the double stabilizer are connected to an intermediate horizontal stabilizer . Thanks to a patented construction, the outer wings can be dismantled and installed under the inner wing on the fuselage in a double-decker configuration .

Wings and tail boom are in shells - sandwich construction of carbon fibers manufactured in the rudder also be aramid fibers used. The wing is profiled with the high-lift profile Wortmann FX 63-137. At the end of with Dacron -covered steel tube truss fuselage under a is Cowling a two-stroke - radial engine mounted by King, who in pusher propeller configuration via a toothed belt acts on a four-wing propeller, which was optionally available as a folding propeller. The nose wheel landing gear is sprung.

The further development of the Stratos 300 was built almost entirely in fiber composite construction. The cockpit with the acrylic glass canopy that folds to the right is similar to that of a glider , the main landing gear swing arm is made up of carbon fiber rovings . A version of the Stratos 300 K with spoilers on the top of the wing is easier to land because the aircraft no longer floats in the ground effect as long as it is used. The two-seater Stratos 400 was planned, as was a motor glider , a mock-up of which was exhibited at the ILA in Hanover in 1990 .

All versions are equipped with a total rescue device.

Technical specifications

Parameter	Data Stratos II	Data Stratos 300
crew	1
length	6.60 m	6.30 m
span	13.60 m	12.60 m
Wing area	15 m²	13.86 m²
Elongation	12.3	11.5
Wing profile	Wortmann FX 63-137
Glide ratio	23	25th
Empty mass	155 kg	170 kg
Max. Takeoff mass	280 kg	300 kg
Wing loading	18.7 kg / m²	21.6 kg / m²
drive	a König SD 570, 21 kW	a König SC 430, 18 kW
Tank capacity		32 l
Minimum speed	45 km / h
Maneuver speed	92 km / h
Top speed	117 km / h
Rate of climb	2.5 m / s
Range	400 km

Web links

Commons : HFL Stratos 300 - Collection of images, videos and audio files

Equipment data sheet 61045, DAeC-Luftsportgeräte-Büro, Edition 6, 2012

Individual evidence

↑ ^a ^b ^c aircraft construction in Lüneburg, HFL a short interlude. (PDF; 9.6 MB) Luftsportverein Lüneburg, accessed on January 15, 2019 .
↑ ^a ^b ^c ^d ^e ^f ^g ^h G. Brinkmann, K. von Gersdorff, W. Schwipps: Stratos . In: Sport and travel aircraft - guidelines for a diverse development . 1st edition. Bernard & Graefe Verlag, Bonn 1995, ISBN 3-7637-6110-1 , p. 290-292, 377 .
↑ Heiko Müller: HK-12 . Successful first flight in Rechlin-Lärz. In: aerokurier . No. 6 , 1995, pp. 72 f .
↑ ^a ^b ^c ^d ^e ^f ^g DAeC device data sheet no. 61045. (PDF; 20 kB) Edition 6. In: daec.de. DAeC Air Sports Equipment Office, February 9, 2012, accessed January 7, 2019 .
↑ ^a ^b ^c ^d Klaus Fritz: Stratos II, Stratos 300. In: aeroklaus.foxflieger.de. Retrieved January 15, 2019 .

[LSV-1] aircraft construction in Lüneburg, HFL a short interlude. (PDF; 9.6 MB) Luftsportverein Lüneburg, accessed on January 15, 2019 .

[SportReise-2] ↑ ^a ^b ^c ^d ^e ^f ^g ^h G. Brinkmann, K. von Gersdorff, W. Schwipps: Stratos . In: Sport and travel aircraft - guidelines for a diverse development . 1st edition. Bernard & Graefe Verlag, Bonn 1995, ISBN 3-7637-6110-1 , p. 290-292, 377 .

[aerokurier0695-3] Heiko Müller: HK-12 . Successful first flight in Rechlin-Lärz. In: aerokurier . No. 6 , 1995, pp. 72 f .

[Kennblatt-4] ↑ ^a ^b ^c ^d ^e ^f ^g DAeC device data sheet no. 61045. (PDF; 20 kB) Edition 6. In: daec.de. DAeC Air Sports Equipment Office, February 9, 2012, accessed January 7, 2019 .

[aeroklaus-5] Klaus Fritz: Stratos II, Stratos 300. In: aeroklaus.foxflieger.de. Retrieved January 15, 2019 .