The Supermarine Air Yacht was a British luxury passenger-carrying
flying boat
A flying boat is a type of seaplane with a hull, allowing it to land on water. It differs from a floatplane in having a fuselage that is purpose-designed for flotation, while floatplanes rely on fuselage-mounted floats for buoyancy.
Though ...
. It was designed by
Supermarine
Supermarine was a British aircraft manufacturer. It is most famous for producing the Spitfire fighter plane during World War II. The company built a range of seaplanes and flying boats, winning the Schneider Trophy for seaplanes with three cons ...
's chief designer
R. J. Mitchell and built in
Woolston, Southampton in 1929. It was commissioned by the brewing magnate
Ernest Guinness, and was the first British flying yacht built to the order of a private owner. Only one machine was built.
The Air Yacht was intended to cover without re-fuelling, with a
cruising speed
Cruise is the phase of aircraft flight from when the aircraft levels off after a climb until it begins to descend for landing. Cruising usually comprises the majority of a flight, and may include small changes in heading (direction of flight), ...
of . It resembled the
Dornier Do J
The Dornier Do J ''Wal'' ("whale") is a twin-engine German flying boat of the 1920s designed by ''Dornier Flugzeugwerke''. The Do J was designated the Do 16 by the Reich Air Ministry (''RLM'') under its RLM aircraft designation system, aircraft ...
, with the rectangular flat-sided wing spanning and held high above the fuselage. The three
engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
s were mounted on the leading edge of the wing, and the single braced
tailplane
A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...
had three vertical fins and
rudders
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually aircraft, air or watercraft, water). On an airplane, the rudder is used primarily to c ...
. The interior was fitted in a luxurious fashion, with an enclosed cabin for the owner, and a separate cabin for five other passengers.
It first flew in February 1930, before undergoing trials the following year at
Felixstowe
Felixstowe ( ) is a port town and civil parish in the East Suffolk District, East Suffolk district, in the county of Suffolk, England. The estimated population in 2017 was 24,521. The Port of Felixstowe is the largest Containerization, containe ...
. During the trials it handled well, but was underpowered and
climbed poorly; the three engines were subsequently replaced with
Armstrong Siddeley Panthers. Guinness refused to complete the purchase, and the plane was put into storage. In October 1932 it was bought by a local wealthy American, Mrs June Jewett James. Soon afterwards it left England for Egypt, but stormy weather forced it to land off
Cherbourg
Cherbourg is a former Communes of France, commune and Subprefectures in France, subprefecture located at the northern end of the Cotentin peninsula in the northwestern French departments of France, department of Manche. It was merged into the com ...
, and the crew, along with James and her fellow passengers, were rescued. On 25 January 1933 engine failure caused the plane to ditch into the
Gulf of Naples
The Gulf of Naples (), also called the Bay of Naples, is a roughly 15-kilometer-wide (9.3 mi) gulf located along the south-western coast of Italy (Metropolitan City of Naples, Campania region). It opens to the west into the Mediterranean ...
, causing several injuries. The airplane was recovered and impounded by the Italian authorities, but was too damaged to be repaired, and was sold for scrap.
Development
Supermarine
Supermarine was a British aircraft manufacturer. It is most famous for producing the Spitfire fighter plane during World War II. The company built a range of seaplanes and flying boats, winning the Schneider Trophy for seaplanes with three cons ...
's chief designer
R. J. Mitchell was responsible for the design of two
air yachts, both of which originated from military commissions. The
Supermarine Nanok, an armed version of the
Supermarine Southampton
The Supermarine Southampton was a flying boat of the interwar period designed and produced by the British aircraft manufacturer Supermarine. It was one of the most successful flying boats of the era.
The Southampton was derived from the expe ...
built at the company's works at
Woolston, was designed for use by the Danish government, but the airplane performed poorly and was rejected by the Danes. The
hull was refitted as a luxury cruiser—the
Supermarine Solent—and was sold in 1928 to
Ernest Guinness, a member of the
Guinness family
The Guinness family is an extensive Irish family known for its achievements in brewing, banking, politics, and religious ministry. The brewing branch is particularly well known among the general public for producing the dry stout beer Guinnes ...
. In 1930 Guinness, who then possessed the air yacht and three other aircraft, owned more private planes than anyone else in Britain.
The Solent was
registered as a civilian aircraft and given the registration GAAAB. Guinness made regular trips to and from
Southampton Water to
Lough Corrib, near his family home. However, the Solent's hull had a restricted height and passengers were unable to stand up fully once inside.
Guinness commissioned Mitchell's second luxury craft, the Supermarine Air Yacht, as a replacement for the Solent. The Air Yacht was to be used by Guinness for pleasure cruising around the
Mediterranean
The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...
.
It was the first British flying yacht built to the order of a private owner, and the first of Supermarine's
monoplane
A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings.
A monoplane has inherently the highest efficiency and lowest drag of any wing con ...
s to be
multi-engined. Based on a 1927 design originally made for the requirements of
specification R5/27 for a
reconnaissance
In military operations, military reconnaissance () or scouting is the exploration of an area by military forces to obtain information about enemy forces, the terrain, and civil activities in the area of operations. In military jargon, reconnai ...
flying boat for the
Royal Air Force
The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...
,
it was built at the Supermarine works in 1929. The price agreed was £34,888 (), but the production costs reached £52,000 ().
Design
The resulting modified design was a flying boat that weighed , powered with three
Armstrong Siddeley Jaguar engines.
It included hull-mounted
sponson
Sponsons are projections extending from the sides of land vehicles, aircraft or watercraft to provide protection, Instantaneous stability, stability, storage locations, mounting points for weapons or other devices, or equipment housing.
Watercra ...
s instead of the wing-mounted
floats common on aircraft of this type, which caused it to resemble the German
Dornier Do J
The Dornier Do J ''Wal'' ("whale") is a twin-engine German flying boat of the 1920s designed by ''Dornier Flugzeugwerke''. The Do J was designated the Do 16 by the Reich Air Ministry (''RLM'') under its RLM aircraft designation system, aircraft ...
;
a Supermarine employee afterwards wrote of Mitchell that "he had allowed himself to be lured by some of his bright boys into following other people's ideas." Instead of a wooden
biplane
A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...
, Mitchell designed a
monoplane
A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings.
A monoplane has inherently the highest efficiency and lowest drag of any wing con ...
made of metal, with the wing held high above the fuselage on
struts and stabilised laterally.
The rectangular flat-sided
parasol
An umbrella or parasol is a folding canopy (building), canopy supported by wooden or metal ribs that is mounted on a wooden, metal, or plastic pole. It is usually designed to protect a person against rain. The term ''umbrella'' is traditionall ...
wing had a span of and sloping V struts for support, and was strengthened with horizontal corrugations. The three
radial engine
The radial engine is a reciprocating engine, reciprocating type internal combustion engine, internal combustion engine configuration in which the cylinder (engine), cylinders "radiate" outward from a central crankcase like the spokes of a wheel. ...
s were mounted on the leading edge of the wing. The single braced
tailplane
A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...
had three vertical fins and
rudders
A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually aircraft, air or watercraft, water). On an airplane, the rudder is used primarily to c ...
. The aircraft's surfaces were covered with fabric.
When loaded with a full tanks of petrol, of baggage, and a minimum crew of three, the Air Yacht was designed to cover a distance of without re-fuelling. It was designed to have a
cruising speed
Cruise is the phase of aircraft flight from when the aircraft levels off after a climb until it begins to descend for landing. Cruising usually comprises the majority of a flight, and may include small changes in heading (direction of flight), ...
of . and a top speed of .
The crew were accommodated in open
cockpit
A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle.
The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...
s in the nose. There was an enclosed cabin for the owner, with its own toilet, bath and bed, and a separate cabin and seating for the other five passengers. The
galley
A galley is a type of ship optimised for propulsion by oars. Galleys were historically used for naval warfare, warfare, Maritime transport, trade, and piracy mostly in the seas surrounding Europe. It developed in the Mediterranean world during ...
was located beneath the wing.
The passenger areas were fitted with deep-pile carpets and luxurious furniture; their cabin was long, high and wide.
Performance

The Air Yacht, which was designated G-AASE,
made its first flight in February 1930 at
Hythe, Hampshire
Hythe () is a town in Hampshire, England. It is located by the shore of Southampton Water, and has a ferry service connecting it to Southampton. Hythe has a shopping area, a pier, and a marina for yachts.
History
The name Hythe means land ...
. During the summer months of 1931 it underwent trials at the
Marine Aircraft Experimental Establishment (MAEE) at
Felixstowe
Felixstowe ( ) is a port town and civil parish in the East Suffolk District, East Suffolk district, in the county of Suffolk, England. The estimated population in 2017 was 24,521. The Port of Felixstowe is the largest Containerization, containe ...
. When tested carrying loads of , the plane handled well, but couldn't keep height when the fuel flow was reduced. Excess
drag was created by the sponsons, one of which suffered from
structural failure
Structural integrity and failure is an aspect of engineering that deals with the ability of a structure to support a designed structural load (weight, force, etc.) without breaking and includes the study of past structural failures in order to ...
. The aircraft lost power in one engine and so failed to maintain a high enough altitude needed to be considered safe.
Tests also revealed the aircraft was underpowered with a long
takeoff
Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff.
For aircraft that take off horizontally, this usually involves starting with a tr ...
run, and poor
climb.
The three engines were replaced with three
Armstrong Siddeley Panthers, which increased the flying boat's maximum speed, but which still left it incapable of maintaining height when fully loaded with passengers, stores and fuel. It was certified as being airworthy on 22 December 1931, but the aircraft was rejected by Guinness for failing to meet his specifications. He later purchased a
Saro Cloud.
Operational history
Having failed to be purchased, the Air Yacht was put into storage by Supermarine.
In October 1932, it was seen by chance and then bought by a local wealthy American, Mrs June Jewett James, who knew little of the practicalities of flying an aircraft. James publicised her intention to use the flying boat to establish a regular trans-Atlantic service for passengers and
cargo
In transportation, cargo refers to goods transported by land, water or air, while freight refers to its conveyance. In economics, freight refers to goods transported at a freight rate for commercial gain. The term cargo is also used in cas ...
, once trials had been completed.

A month after having been bought by James,
the flying boat, now named ''Windward III'', left Woolston on a flight to Egypt. It took off on 11 October 1932, with June James, her daughter, a
governess
A governess is a woman employed as a private tutor, who teaches and trains a child or children in their home. A governess often lives in the same residence as the children she is teaching; depending on terms of their employment, they may or ma ...
, and two crew members on board.
During the flight deteriorating weather conditions forced it to land off the coast near
Cherbourg
Cherbourg is a former Communes of France, commune and Subprefectures in France, subprefecture located at the northern end of the Cotentin peninsula in the northwestern French departments of France, department of Manche. It was merged into the com ...
.
On October 14, whilst in Cherbourg harbour, the crew and passengers had to call to be rescued and were landed onshore by
tugboats
A tugboat or tug is a marine vessel that manoeuvres other vessels by pushing or pulling them, with direct contact or a tow line. These boats typically tug ships in circumstances where they cannot or should not move under their own power, such ...
, where they remained to await better flying conditions.
The plane then flew on to
Naples
Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...
, where James obtained audiences with
Pope Pius XI
Pope Pius XI (; born Ambrogio Damiano Achille Ratti, ; 31 May 1857 – 10 February 1939) was head of the Catholic Church from 6 February 1922 until his death in February 1939. He was also the first sovereign of the Vatican City State u ...
and the Italian dictator,
Benito Mussolini
Benito Amilcare Andrea Mussolini (29 July 188328 April 1945) was an Italian politician and journalist who, upon assuming office as Prime Minister of Italy, Prime Minister, became the dictator of Fascist Italy from the March on Rome in 1922 un ...
.
The flight to Egypt resumed on 25 January 1933, but an engine failed on take-off and later stalled, causing the flying boat to ditch into the
Gulf of Naples
The Gulf of Naples (), also called the Bay of Naples, is a roughly 15-kilometer-wide (9.3 mi) gulf located along the south-western coast of Italy (Metropolitan City of Naples, Campania region). It opens to the west into the Mediterranean ...
off
Sorrento
Sorrento ( , ; ; ) is a City status in Italy, city and overlooking the Gulf of Naples, Bay of Naples in Southern Italy. A popular tourist destination, Sorrento is located on the Sorrentine Peninsula at the southern terminus of a main branch o ...
.
The crew and passengers were rescued by local fishermen, who later recovered the aircraft from the water.
The most serious casualty was James, who suffered two broken ribs and a broken leg.
The crash caused the aircraft's wing to break. The authorities in Capri impounded the plane against a
salvage claim. Too damaged to be repaired, it never flew again, and was sold for scrap the following year; only the engines were returned to England.
James was declared
bankrupt
Bankruptcy is a legal process through which people or other entities who cannot repay debts to creditors may seek relief from some or all of their debts. In most jurisdictions, bankruptcy is imposed by a court order, often initiated by the de ...
in July 1933.
Specifications
See also
*
List of flying boats and floatplanes
The following is a list of seaplanes, which includes floatplanes and flying boats. A seaplane is any airplane that has the capability of landing and taking off from water, while an amphibian is a seaplane which can also operate from land. (They d ...
Notes
References
Sources
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Further reading
*
External links
Image of a surviving part of the Supermarine Air Yacht(Wick Antiques Ltd.)
Image of the Air Yacht's civil registration certificate
{{Supermarine aircraft
1930s British civil utility aircraft
Flying boats
Air Yacht
Parasol-wing aircraft
Trimotors
Aircraft first flown in 1930