1962 – RV Spenser F. Baird – The Proa Expedition, Leg 2, returned Fisher to the Challenger Deep on 12–13 April 1962 aboard the Scripps research vessel Spencer F. Baird (formerly the steel-hulled US Army large tug LT-581) and employed a Precision Depth Recorder (PDR) to verify the extreme depths previously reported. They recorded a maximum depth of 10,915 metres (35,810 ft) (location not available).[34] Additionally, at location "H-4" in the Challenger Deep, the expedition cast three taut-wire soundings: on 12 April, the first cast was to 5078 fathoms (corrected for wire angle) 9,287 metres (30,469 ft) at 11°23′N 142°19.5′E﻿ / ﻿11.383°N 142.3250°E﻿ / 11.383; 142.3250 in the central basin. (Up until 1965, US research vessels recorded soundings in fathoms.)