The Bonomi BS.28 Alcione (English: Halcyon or Kingfisher), sometimes known as the Lombarda BS.28 Alcione, was a single seat competition sailplane designed and built in Italy in 1937-8. About four were completed, with two more or less refined fuselages.
The Alcione was the last of many gliders designed by Camillo Silva at Aeronautica Benomi,[1] as the latter was taken over in 1937 by Aeronautica Lombarda.[2] The change of ownership led to the Alcione being referred to as both a Bonomi and a Lombarda. Silva designed at least one further glider for Lombarda, the AL-3[3] which was one of two Italian competitors in the 1939 Olympic Sailplane Competition of 1939.[4]
The Alcione was a refined sailplane in its day, designed in collaboration with the Polytechnic University of Milan. It was a cantilevermid-wing monoplane, its wing built around a single spar at about one third chord. Forward of the spar the wing was plywood covered, forming a torque resisting D-box; elsewhere it was fabric covered. In plan the wings were straight tapered to rounded tips.[5] The whole trailing edge of each wing was moveable, the inner third acting as camber changing air brakes and the rest as differential ailerons.[6]Spoilers of the early, single action Centro Volo a Vela (CVV) type were mounted on the upper wing surface immediately behind the spar and at about one quarter span.[5][6]
Two different fuselages were built for the Alciones. Both had the same general form, deep under the cockpit which was placed forward of the wing leading edge under an enclosing canopy. There was a short landing skid, ending aft at a semi-recessed wheel at about mid chord. However, one fuselage type had a hexagonal cross-section and the other was better shaped aerodynamically as an ovoid. The latter was lower along the dorsal line, so the other's glazed cockpit cover was lengthened aft with a ply covered extension including small side windows. The lower line also required the addition of a very short pedestal for the tailplane, directly mounted onto the hexagonal fuselage. The horizontal tail was straight tapered and round tipped, placed with its trailing edge in line with that of a narrow fin so that no cut-out for rudder movement was needed. On the ovoid fuselage version with its small pedestal the fin reached only about halfway to the top of the rudder, allowing the inclusion of an aerodynamic balance. On the other fuselage the fin continued upwards to the rudder tip. The rudder itself was broad and D-shaped. There was a little tail bumper on the fuselage keel at the rudder's foot.[5]
The ovoid fuselage version became known as the B.28 Aerodinamico.[7]
The Alcione dates from either 1937[6] or 1938,[5] with registration dates[8] supporting the latter. Images[5] identify three examples and the register a fourth.[8]
Operational historyedit
An Alcione took part in the Asiago Gliding Competition of 1938.[5]
bonomi, alcione, english, halcyon, kingfisher, sometimes, known, lombarda, alcione, single, seat, competition, sailplane, designed, built, italy, 1937, about, four, were, completed, with, more, less, refined, fuselages, alcionerole, competition, sailplanenatio. The Bonomi BS 28 Alcione English Halcyon or Kingfisher sometimes known as the Lombarda BS 28 Alcione was a single seat competition sailplane designed and built in Italy in 1937 8 About four were completed with two more or less refined fuselages BS 28 AlcioneRole Competition sailplaneNational origin ItalyManufacturer Aeronautica BonomiDesigner Camillo SilvaFirst flight c 1938Number built c 4 Contents 1 Design and development 2 Operational history 3 Specifications 4 ReferencesDesign and development editThe Alcione was the last of many gliders designed by Camillo Silva at Aeronautica Benomi 1 as the latter was taken over in 1937 by Aeronautica Lombarda 2 The change of ownership led to the Alcione being referred to as both a Bonomi and a Lombarda Silva designed at least one further glider for Lombarda the AL 3 3 which was one of two Italian competitors in the 1939 Olympic Sailplane Competition of 1939 4 The Alcione was a refined sailplane in its day designed in collaboration with the Polytechnic University of Milan It was a cantilever mid wing monoplane its wing built around a single spar at about one third chord Forward of the spar the wing was plywood covered forming a torque resisting D box elsewhere it was fabric covered In plan the wings were straight tapered to rounded tips 5 The whole trailing edge of each wing was moveable the inner third acting as camber changing air brakes and the rest as differential ailerons 6 Spoilers of the early single action Centro Volo a Vela CVV type were mounted on the upper wing surface immediately behind the spar and at about one quarter span 5 6 Two different fuselages were built for the Alciones Both had the same general form deep under the cockpit which was placed forward of the wing leading edge under an enclosing canopy There was a short landing skid ending aft at a semi recessed wheel at about mid chord However one fuselage type had a hexagonal cross section and the other was better shaped aerodynamically as an ovoid The latter was lower along the dorsal line so the other s glazed cockpit cover was lengthened aft with a ply covered extension including small side windows The lower line also required the addition of a very short pedestal for the tailplane directly mounted onto the hexagonal fuselage The horizontal tail was straight tapered and round tipped placed with its trailing edge in line with that of a narrow fin so that no cut out for rudder movement was needed On the ovoid fuselage version with its small pedestal the fin reached only about halfway to the top of the rudder allowing the inclusion of an aerodynamic balance On the other fuselage the fin continued upwards to the rudder tip The rudder itself was broad and D shaped There was a little tail bumper on the fuselage keel at the rudder s foot 5 The ovoid fuselage version became known as the B 28 Aerodinamico 7 The Alcione dates from either 1937 6 or 1938 5 with registration dates 8 supporting the latter Images 5 identify three examples and the register a fourth 8 Operational history editAn Alcione took part in the Asiago Gliding Competition of 1938 5 Specifications editData from Pedrielli 2011 p 107 5 General characteristicsCrew One Length 6 55 m 21 ft 6 in Wingspan 14 50 m 47 ft 7 in Wing area 14 m2 150 sq ft Aspect ratio 15 Empty weight 160 kg 353 lb Gross weight 254 kg 560 lb Performance Maximum glide ratio 22 1 estimated Rate of sink 0 75 m s 148 ft min 6 Wing loading 17 50 kg m2 3 58 lb sq ft References edit Pedrielli Vincenzo Camastra Francesco 2011 Italian Vintage Sailplanes Konigswinter EQIP Werbung amp Verlag GmbH pp 72 107 ISBN 9783980883894 Thompson Jonathan 1963 Italian Civil and Military Aircraft 1930 1945 Fallbrook California Aero Publishers Inc p 293 Pedrielli Italian Vintage Sailplanes p 67 Simons Martin 2006 Sailplanes 1920 1945 2nd revised ed Konigswinter EQIP Werbung amp Verlag GmbH pp 198 9 ISBN 3 9806773 4 6 a b c d e f g Pedrielli Italian Vintage Sailplanes pp 106 107 a b c d Zuerl Hubert 1941 Segelflug im Wettbewerb der Volker Berlin E S Mittler amp Sohn p 42 Bonomi BS 28 Aerodinamico Retrieved 1 January 2014 a b Air Britain pre war Italian register Malcolm Fillmore Portals nbsp Italy nbsp Companies nbsp Aviation Retrieved from https en wikipedia org w index php title Bonomi BS 28 Alcione amp oldid 1087932566, wikipedia, wiki, book, books, library,
