|Name||No||Yard No||Builder||Laid down||Launched||Comp||Fate|
|D1||S11||SECN, Cartagena||23.9.1933||11.5.1944||17.3.1947||stricken 2.1965|
|D2||S21||SECN, Cartagena||19.11.1934||21.12.1944||23.5.1951||stricken 4.1971|
|D3||S22||SECN, Cartagena||11.12.1934||20.2.1952||20.2.1954||stricken 2.1971|
|Displacement standard, t|
|Displacement normal, t||
1065 / 1399
|No of shafts||
Sulzer diesels / electric motors
|Power, h. p.||
5000 / 1350
|Max speed, kts||
20.5 / 9.5
diesel oil 151
|Endurance, nm(kts)||9000(10) / 100(4)|
1 x 1 - 88/45 SK C/35, 1 x 1 - 20/65 C/38, 6 - 533 TT (4 bow, 2 stern, 16)
|Electronic equipment||GHG hydrophone|
|Diving depth operational, m||60|
Design of large fast oceangoing submarine, known as No22, or "Sigma II", has been developed under the guidance of director of SECN, Cartagena A. F. Avila. Lead D1 was built under the law from 30.8.1932, two others were authorized by the law from 27.3.1934, building was conducted with assistance of Vickers-Armstrong. Originally artillery should consist of one 120mm gun Vickers-Armstrong and two AA MG. Building was quickly suspended in view of insufficient financing, excessive complexity of project for Spanish industry, and also long-term assimilation of licence production of powerful 2500hp "Sulzer" diesels by SECN. To the beginning of Civil war all three submarines were on slipways and in 1937 their building was suspended. Building was renewed in February, 1940 under modified design with replacement of British-made equipment by German and Italian. Instead of 120mm gun there was installed 88mm/45 SKC/35. Defeat of Axis has led to strong delay of commission of D2 and D3 (latter was really completed only in 1956). D class submarines appeared the extremely unsuccessful ships, having vicious constructed ballast system, low stability, numerous hull defects, bad ventilation and habitability. Sulzer diesels of Spanish production suffered from strong vibration and had low reliability, their operation on full speed has been forbidden. Maximum diving depth was been limited by 60m. Actually boats were always unoperable and almost all time conducted in repairs and fittings.
1961, D1: - 1 x 1 - 88/45
1963, D2, 3: hull and conning tower were streamlined; - 1 x 1 - 88/45, 2 - 533 TT (stern, 12 torpedoes at all).
No significant events.