J.Davilla Italian Aviation in the First World War. Vol.2: Aircraft A-H (A Centennial Perspective on Great War Airplanes 74)

Ansaldo ISVA

  The ISVA (Idrovolante SVA = SVA seaplane) was a version of the standard SVA 5 which was equipped with tubular floats. The aircraft was fitted with a 200-hp SPA 6A engine and was designed at the request of the Direzione Superiore del’Aeronautica in order to take advantage of the high speed developed by the SVA series.


Technical

  Wings - The Warren truss arrangement of the struts with only one pair per side was found to provide a strong structure. It was not easy to mass produce, however, as it required special machining to complete the assembly.
  Fuselage - The fuselage was of the standard SVA design, meaning it was robust, but at the cost of poor forward and downwards visibility.
  Tail - The areas of the tail planes, at the extremity of the fuselage, had the following surface areas: Fixed horizontal surface 0.70 sq m; horizontal rudders 1.20 sq m; fixed vertical fin 0.45 sq m; rudder 0.85 sq m; elevators 1.25 sq m.
  Flight controls - Maneuvers were performed with the usual lever and pedal system; the controls were very short and straight, given the proximity of the pilot to the maneuvering planes, and remained well protected inside the fuselage. Even the engine or fuel controls were better protected from the elements as compared to the standard Macchi or SIAI flying-boats.
  Floats - Two Guidoni floats with a cylindrical body and two hydroplane vanes, two per float located in tandem. Their dimensions Length 5.60 m, diameter 0.50 m, distance between the floats 2.40 m; volume of each float 0.950 cubic meters; weight 56 kg.
  The entire float assembly weighed about 160 kg, complete with accessories, which represented 15% of the total weight.
  Take off from the water and ditching were made very easy by the use of hydroplane fins; but the possibility that algae or other foreign bodies could become entangled in the latter compromises the rapidity of lifting off from the water. Magaldi, in Gli Idrovolanti in Italia page 152, stated that: Together with M.7 the ISVA is one of the fastest seaplanes in the world, and is on par with many of the best land-based fighters. It could reach 4,000 m in 22 minutes. He felt that it would have seen widespread use had it been produced earlier in the war.


Operational Service

  Only 50 examples were built and saw service with only four naval Squadriglias, four Seaplane Stations, and two training centers. At the end of 1917 the test pilot collaudatore sergente Mario Stoppani achieved a world height record for seaplanes, reaching 6,200 m.
  The Ansaldo ISVAs were assigned for evaluation at Squadriglias in quieter areas of the front. This turned out to be a wise decision, as they were found to be underpowered. Many were returned to Ansaldo as not combat ready. During 1918, ISVAs were assigned to the following units:

Seaplane Stations
  Brindisi - 3 ISVAs
  Civitavecchia - 1 ISVA
  Valona - 1 ISVA
  Varano - 5 ISVAs

Ships
  R.N. Europa - 3 ISVAs

Training units
  Bolesna - 5 ISVAs
  Taranto - 5 ISVAs

Units
  258a Squadriglia
   In the summer of 1918 the unit also began evaluation of the Ansaldo ISVA, a floatplane version of the SVA.

  260a Squadriglia
   This unit had at least four ISVAs. They were described as being useable due to their temperamental engines. In July the ISVAs were returned to Ansaldo.

  272a Squadriglia
   The 9th Sezione FBA was based at Civitavecchia on 1 June 1917 with only two FBAs. On 15 May 1918 it was reactivated as 272a Squadriglia. In the summer, 272a received ISVA 15263. The ISVA was lost on July 10, but close to end war 272a received another ISVA, 15248, 272a was disbanded December 6 1918.

288a Squadriglia
   Formed at the end of October 1918 at Valona with M.5s drawn from Squadriglias 257A and 258a. It also employed some ISVAs.

290a Squadriglia
   Formed at Varano, with the commander Alberto Ghe and pilots Vincenzo Coscione, Pero Guinzani, and Amedeo Formica. It was equipped with M.5 and ISVAs. It was disbanded postwar.


Foreign service

  Brazil - The Aviacao Navale acquired two ISVAs in 1919. They were assigned serials 26 and 27. The aircraft were SOC in 1921.


Ansaldo ISVA single-seat floatplane fighter with one 200-hp SPA 6A engine
  Wing span, 9,10 m.; length, 9,37 m; height, 3,46 m.; wing surface, 24,20 mq.
  Empty weight 850 kg.; payload 225 kg.; loaded weight 1,075 kg.;
  Maximum speed, 195 km/h; climb to 4.000 m. in 22’; endurance 3 h.
  Fifty ISVA s were built