Today we’re looking at an aircraft that was built with somewhat old-school thinking,
but still managed to outlive other models that were later designed
to replace it: this was the Curtiss SOC Seagull. In the early 1930s the US Navy was looking for a
new catapult launched observation plane to replace the Vought O2U and O3U floatplanes, and in answer
to a new specification, they received submissions from Vought, Douglas, and Curtiss in early 1933.
The design submitted by Curtiss appeared to be a throwback to the 1920s, at least on first
appearance. Their prototype proposal, the model 71 - which would later be known as the XO3C-1-
was an equal span biplane design with moderate wing stagger. The fuselage was constructed of
welded steel tube framing, and although it was covered with aluminium panelling on the front,
the rear was clad in fabric. The wings too were covered in fabric,
and they were built on an aluminium frame with fabric covered control surfaces; as with most
aircraft of this type, these wings could be folded back against the fuselage for shipboard storage.
The prototype had a pair of open cockpits for the pilot and the observer, something that was
rapidly falling out of fashion by this time, and it featured an amphibious landing gear that
retracted into the large single float. As it was to serve at sea, and possibly also crash at sea,
the crew had a fair amount of kit on board. A lift raft was stowed under the pilot’s seat,
a first aid kit was stowed under the rear gun, a toolkit was on the forward side of the firewall,
and a watertight map case was on the lower portside of the front cockpit,
and both crewmembers of course had a flare gun. The features that could be considered ‘modern’
on the plane were relatively few: it had full-span leading edge slats on the upper wing,
trailing-edge flaps on the upper wing, and a streamlined cowling around the engine,
which was a 9-clyinder Pratt & Whitney Wasp that produced approximately 500hp…and
as far as modern things go that was about it. Although aspects of the Curtiss prototype could be
considered basic, or even outdated, this did not represent any sort of regression in their design
thinking. In a time of American isolationism and reduced budgets, courtesy of the great depression,
Curtiss designers knew they needed a plane that was cheap to build, relatively modern, and
sturdy enough for a life at sea. And so they had made their design modern where it needed to be:
with the new control surfaces improving the aircraft low speed handling, and cheap
where it could afford to be; having most of it covered in fabric and made from basic materials.
This design approach paid off, as after competing in trials against the Douglas and Vought
prototypes, the Curtiss prototype was deemed the overall winner and the company was awarded
a contract for 135 production aircraft. The aircraft was first built as the Curtiss XO3C-1,
but then this was updated to the SOC-1 after approximately six months. This change in
designation followed the merging of the scouting and observation roles for ship-launched aircraft;
previously, observation types were deployed on battleships, and scouting types were deployed
on cruisers, now they performed both roles, Compared to the prototype, there were some
improvements made to the production model. Firstly a large canopy was added that enclosed both
cockpits, this was streamlined into the tail by a collapsible turtledeck that could be
lowered to allow the rear-gunner a clear field of fire. The production model also
featured a more powerful version of the Wasp engine, now producing 550hp, and the
engine now had a full NACA-style cowling. Changes were also made to the undercarriage;
the amphibious unit was removed, and production models would either come
with a standard float for use aboard ships, or a fixed undercarriage for use aboard carriers
or when deployed to coastal airfields. Deliveries of the first SOC-1s began
on November the 12th 1935, with the light cruiser USS Marblehead being the first ship
to officially receive its aircraft. In terms of operational use, with the exception of carriers,
all SOCs operated on a single float and were launched from shipboard catapults while at sea.
After completing a mission, the recovery procedure was rudimentary but effective. The ship would make
a large, sweeping turn by which the ship’s wake would produce a relatively calm area
of sea for the plane to land upon. Once on the water, the pilot would taxi alongside the ship,
which would be towing along a so-called ‘plane trap’, which was basically a giant reinforced net.
The plane had a rearward angled bar that acted like a hook, so that when it came up over this
net the pilot simply had to power down for the plane to be caught. The observer would
then attach a hook that was lowered down by the ship, and the plane could be hauled up.
Multiple versions of the SOC1would be built during the 1930s. After the completion of the initial
production order for 135 SOC-1s, an order for 40 land-based SOC-2s was placed. Aside from the fixed
landing gear, this model also had another improved version of the Wasp engine, this one being the
R-1240-22. And not long after this, an order of 83 SOC-3s was placed, these were identical to the
SOC-2, but their landing gear was designed to be easily interchangeable with a float.
Additionally, some versions of these two models were later used for carrier operations,
and they would be known as the SOC-2A and 3A respectively. The last three SOC-3s
from the production order were modified and given to the US Coast Guard as the SOC-4,
however these were later reacquired by the Navy in 1942 and modified to SOC-3As.
To comply with a Navy policy to build 10 percent of its own service aircraft,
64 SOCs were ordered from the Naval Aircraft Factory. These were generally equivalent to
the SOC-3, but they were designated as the SON-1, and then later SON-1A for the
aircraft modified again to operate on carrier. The SOC was not known as the Seagull until 1941,
when it became commonplace for the Navy to adopt popular names as an addition to the
aircraft’s official designation. However, by mid-1941 all battleship observation squadrons
had now been equipped with the newer Vought OS2U and most Seagulls were in reserve units.
Following the attack on Pearl Harbour things quickly changed. The SOCs were quickly pressed
back into frontline service, with almost all cruisers in the US Navy operating the plane
in 1942. A new type of operation for the aircraft began in 1941, when several SOC-3s were converted
to the SOC-3A for carrier use. The first twelve of these served with Brewster Buffalos aboard
the first escort carrier, USS Long Island. By late 1942 four other escort carriers were operating the
Seagull in the Pacific Fleet, and they were also operated by the USS Charger in the Atlantic.
Their return to service life was partly due to the war, but also due to the fact that the Seagul
had managed to remain superior to the aircraft designed to replace it. By the Spring of 1938
the production of the Seagull had ended, as work had already begun on a monoplane scout aircraft to
replace it. However, this new plane – the Curtiss SO3C- proved to be a colossal disappointment,
and its hasty withdrawal from service kept the old Seagulls relevant until 1945.
Ultimately, 322 Seagulls would be produced, and they would see service in the Atlantic and
Pacific Oceans, as well as the Mediterranean. Generally, they were very well liked by both
their pilots and the crews that serviced them. Unfortunately, no example this naval workhorse
can be found today, which is a shame as it’s an often-underappreciated plane.
Along with the failed SO3C, they would be the last aircraft of this type developed by Curtiss,
and indeed it was one of the last mass-produced aircraft designed to be carried and launched
by US naval vessels, as they were soon replaced in this role by Naval helicopters.