The SP-2H Neptune patrol aircraft was quite a change from the RA-5C. Still, there were enough challenges in the tranition to make it interesting. Learning the fundatmentals about antisubmarine warfare was one such challenge. Aboard an attack aircraft carrier we didn't bother about such things, but in the real world the Navy placed a very high priority in countering the soviet submarine threat.
In the early '70's, when I affiliated with the reserves, the reserve patrol forces were tranitioning from the SP-2H to the P-3A Orion. In addition having an avionics suite generations more advanced from that of the SP-2H, was a robust and efficient airframe based on the commercial Electra transport built by Lockheed. VP-94 was the last US Navy squadron to operate the model, retiring its last SP-2H in 1978.
Designed during World War II, the P-2 (originally P2V) was designed as a twin reciprocating engine patrol bomber. As time passed, additional requirements let to inclusion of additinal equipment, including the APS-20 radar in a large chin radome. This in turn led to installation of two auxillairy jet engines in underwing pods.
As a navigator , my station was aft of the "Jezebel" operator and forward of the tactical coordinator's station. The acoustic equipment on the SP-2H was the AQA-4 acoustic processor. It was capable of displaying data from up to four sonobuoys. The spectral content of the signal was printed on to special paper, with the frequency on one axis and time on the other.
General layout of the SP-2H interior
View of Navigator's Station. The DRT tracker is in the foreground, with nav instruments directly above.
SP-2H TACCO station. ASA-16 tactical scope on the right, with the APS-20 radar control panel on the left
The acoustic sensor station, also know as the "Jezebel" station was located forwardmost in the cabin and is shown at left. The relative featureless equipment taking up the lower right hand part of the station in the control and display unit for the AN/AQA-4 acoustic sensor. This allowed a crew to monitor four sounobuoys at one time, or 8 with degraded sensitivity. In comparison, the P3A/D with its AQA-7could monitor 16 sonobuoys at once with greatly enhanced senstitivity (13 dB of subclutter visibility) to boot.
The P-2 was also an uncomfortable aircraft to boot. It cruised at 180 knots and thus many transits were quite long. The cabin was unpressurized and could be on the hot side. The aircraft was, like most reciprocating engined aircraft also noisy. Getting around the fuselage required some occasional acrobatics, like climbing over the main spar to get to the aft fuslage.
It wasn't all bad, of course. The glass nose and the large ports in the fuselage made it an excellent platform for visual search. The wing was fairly flexible and smoothed out turbulent air to some extent, especially compared to the stiff-winged P-3. No galley, but electrical connections for hot plates.