The British twin-engined biplane flying boat, known as the English Electric P.5 Kingston, was constructed by the esteemed English Electric Company.
In the year 1918, when the English Electric Company was established through the amalgamation of various entities, the Phoenix Dynamo Manufacturing Company contributed the two initial prototype Phoenix P.5 Cork reconnaissance flying boats.
Following a comprehensive redesign, the Cork resurfaced as the English Electric P.5 Kingston, subsequently receiving a production order for a total of five aircraft.
In 1922, W.O. Manning spearheaded a team of designers tasked with creating a coastal patrol and anti-submarine flying boat that would meet the Air Ministry Specification 23/23.
Drawing inspiration from the Cork, the team developed a design that bore a striking resemblance to its predecessor, but with a hull that adhered to the latest standards.
Additionally, the Kingston boasted redesigned wingtip floats, extended upper-wing ailerons, and a larger fin and rudder compared to the Cork.
Following the Air Ministry’s decision to commission a prototype, English Electric was contracted in January 1923 to construct the new design at its Preston facility.
The prototype was then transported by road to Lytham for flight trials.
On May 12, 1924, the Ministry conducted an inspection of the prototype, which bore the serial number N168.
Ten days later, on May 22, the aircraft was launched into the Ribble Estuary for its first flight.
However, during take-off, N168 suddenly came to a halt “amidst a cloud of spray” and began to sink.
The crew was ejected from the aircraft, which floated with its wings on the surface.
While the crew was being rescued, the aircraft drifted away and was eventually recovered by a tug, which beached N168.
The flying-boat was subsequently repaired and refloated with the aid of a tug.
However, while being towed, the aircraft was caught in a strong current and struck a pier, necessitating another beaching.
The following day, N168 was recovered to the company slipway.
An investigation into the incident determined that the flying-boat had collided with some flotsam.
Despite the occurrence of an accident, the Air Ministry proceeded to order four additional flying-boats, which were designated as the Kingston Mk. I.
The first of these, the Kingston I N9709, was completed a few months later, with only minor modifications made from the prototype, including a slightly larger beam and two-bladed propellers.
In November 1924, the flying-boat was transported by rail to the Marine Aircraft Experimental Establishment at Felixstowe for acceptance trials.
Although the flying-boat met the type and air-handling requirements, it failed to meet the Ministry’s standards for seaworthiness.
As a result, modifications were made to N9709, including the installation of four-bladed propellers.
On 25 May 1925, shortly after take-off, the engines detached from their mountings, causing the wing structure to fail and resulting in cracks in the hull.
Despite this, the crew escaped unharmed.
The second Kingston I, N9710, took its maiden flight on 13 November 1925 at Lytham and was flown to RAF Calshot for service trials, along with the third flying-boat, N9711.
The fourth flying-boat, N9712, was disassembled, and the hull was relocated to RAE Farnborough for testing purposes.
This fourth aircraft was later reintroduced as N9712 at Lytham, with a new duralumin hull, and became the sole Kingston II.
However, it failed to perform during test flights at Felixstowe, and by 1930, the metal hull was utilized for testing at Farnborough.
The final aircraft to be constructed, N9713, featured a completely redesigned hull, which reverted to wooden construction and was known as the Kingston III.
Although more successful than its predecessors, the Kingston III was retained by the Marine Aircraft Experimental Establishment for experimental work and occasionally used as a crew ferry.
Plans were in place to produce a metal-hulled variant of the Kingston III, but the company’s aircraft department closed on the day the Kingston III departed Lytham for Felixstowe in 1926.
Following some sub-contract work during the war, the aircraft department was not reestablished until 1944.