In U.C. 0075, the Earth Federation Forces ordered the construction of eight Lockwood-class submarines as part of the defense buildup plan. Vessels No.1 and 2 were laid down by the end of U.C. 0075, with vessels No.3-7 being carried out in U.C. 0077. Lockwood-class submarines No.1-3 were commissioned and launched in U.C. 0078 and vessels No.4-7 followed after in January, U.C.0079. After the second Earth drop operation, all Lockwood-class submarines were captured by Zeon commando units. The eighth vessel was completed at the occupied construction facility. The Lockwood-class submarines that were seized would be refurbished at the California Base as Mad Angler-class submarines and commissioned by the end of September, U.C. 0079.