Today we’re taking a look at the Airspeed A.S.4 Ferry, an adorably unique plane that
was developed in the early 1930s.
It was the second aircraft produced by the Airspeed company, and their first powered
model, the previous AS1 Tern being a glider.
Its origins can be found in the first company board meeting after Airspeed was officially
formed.
Sir Alan Cobham, one of the company’s original directors, wanted a small multi-engine airliner
that could be used as a touring aircraft during his National Aviation Day displays.
Sir Alan was enthusiastic about aviation and like many others he wanted to bring it closer
to the everyday public, something of singular importance after the bleak early days of the
great depression.
Because the displays would be operated from relatively small airfields, the proposed aircraft
would need to have very short take-off and landing requirements while being able to carry
a maximum of ten passengers.
After some preliminary design work, a proposal was submitted and accepted, and towards the
end of 1931 an order was placed for two aircraft with an expected delivery date of April 1932.
Design and construction of these aircraft was carried out at Airspeed’s new facilities
at York.
In its design, the ferry was unusual in a number of ways, and this was usually due to
a decision that was made to improve the viewing experience of the intended passengers.
The Ferry was designed as an equal span biplane, but both wings were positioned much higher
than on traditional biplanes, and this was done to provide an unobstructed view for the
passengers.
The centre section of the lower wings had a pronounced anhedral so that the essential
part of the wing structure connecting to the fuselage did not impede the headroom of the
cabin.
This downward sloping section of wing almost exactly matched the horizontal support for
the fixed undercarriage, which was housed in an aerofoil-shape fairing – giving it
the appearance of a very small third wing.
This was apparently installed for its ground cushioning effect, but it may also have provided
some level of additional lift, though there is no written evidence to support this.
Along with keeping the wings out of the way, the monocoque fuselage was fitted with large
windows that gave commanding views of the outside world.
The interior of the cabin was spartan but practical, and it also offered passengers
a view of the pilot’s cockpit, so that they could see what the pilot’s job was like.
Much like the passengers, the pilot was also afforded excellent visibility, and this was
thanks to the Ferry’s unusual engine layout.
Two de Havilland Gypsy 2 engines were mounted on the lower wing, and an inverted Gypsey
3 engine was mounted on the centre section of the upper wing, above and slightly behind
the cockpit.
Other aircraft had been designed in such a way, but they had been considerably larger
in size, and the Ferry was one of the first aircraft in its weight-class to feature such
a layout.
These engines were fed by a 65-gallon fuel tank mounted above and behind the central
engine.
To facilitate rapid refuelling, as a quick turnaround time between flights was required,
a pipeline was installed that ran down to the side of the fuselage that allowed fuel
to be pumped in more easily from the ground.
Though this was a useful feature, the aircraft was rarely fuelled to maximum capacity.
Its designer, Hessell Tiltman, made the comment that the ferry was an aircraft with a ‘large
cabin and a small petrol tank’.
This was not because the 65-gallon tank was considered small, indeed it provided enough
fuel for five hours of flight at cruising speed, but rather because the Ferry could
not carry its maximum payload of ten passengers if the tank was full.
This was not considered a critical issue, as the Ferry was designed for local flying
when carrying 10 passengers, and this required nowhere near the maximum fuel load.
But the large tank could come be useful for long-distance ferry flights, demonstration
flights, and longer-range charter services where only four or six passengers were accommodated.
Although it was originally intended for pleasure flights or short-haul duties, the designers
took some time to calculate its performance in these other roles.
A six-passenger payload could, for instance, be carried for four hours at cruising speed,
as well as maintain flight at 5000 feet with the loss of one engine.
Safe cruising could also be done at altitudes of 8,000 feet on two engines, but the passenger
load would have to be reduced down to five.
During the early phases of the Ferry’s development, Airspeed ran into regulation difficulties
when it came to the aircraft’s required equipment.
The ruling at the time was that any aircraft with 10 or more passenger seats had to have
radio equipment on board, but, in order to fit the required radio equipment one passenger
seat would be sacrificied…thus removing the legal requirement for said radio in the
first place.
In the end, and after some behind-the-scenes deliberation, the Ferry was allowed to be
completed without the radio equipment as it would only be used for short flights during
the upcoming air displays.
Construction of the first Ferry was completed in under 10 months, and it was ready to be
prepared for its first flight in March of 1932.
Instead of dismantling, transporting, and re-assembling the aircraft at the nearest
airfield, the decision was made to transport it by road.
This was done at night with a police escort, which proved just as well as it nearly collided
with the giant rudder of the SS Berengaria, which was being transported down the same
road in the opposite direction.
On the 5th of April, after complete assembly and inspection, the first flight was made
with Capt H.V Worral at the controls and following some minor adjustments to correct an overbalanced
rudder, and a tendency for it to fly nose-heavy, the Ferry began its loaded weight tests.
During said tests the take-off run was not considered satisfactory at 570 feet, and the
time of 45 minutes to climb to 10,000 feet was also disappointing.
It was noted however, that the rpm at take-off was lower than expected, and following the
installation of finer-pitch propellers the take-off and climbing performance of the aircraft
significantly improved.
These changes delayed the things enough that the Ferry was going to miss the beginning
of the National Aviation events.
But with the help of the Air Ministry and RAF test pilots, the Ferry blazed through
its official trials at Martlesham heath in just four days, and it was officially delivered
and deemed flightworthy on the 24th of April.
Though it had missed the opening ceremony of the event, a special showing was arranged
for the Ferry on the 4th of May, after which it joined the fleet of touring aircraft that
took excited passengers into the air, many of whom were flying for the first time.
Flying with the official name Youth of Britain II, its unique appearance allowed it to stand
out from the other aircraft and it quickly became one of the tours most popular planes.
The second Ferry was completed not too long after the first, and it joined its sibling
on the tour at the beginning of June.
Unfortunately, it would be damaged in an accident in July, and so the first ferry would do more
of the lifting work.
Despite this though, they would together log over 640 flight hours in the first season
of the tour, making 9,100 landings and carrying 92,000 passengers.
They proved remarkably easy to fly, and their design allowed very quick turnarounds between
flights, some of them being accomplished within 30 seconds, and refuelling only took on average
one-and-a-half minutes.
Considering they were the first powered designs built by airspeed, they had proven to be incredibly
successful, and they allowed airspeed to gain a good early reputation, as well as some much-needed
income.
Individually, they brought in 400 pounds per-week in revenue, the amount paid by Sir Alan for
using them in the Air Displays.
But despite this apparent early success, only four of these curious aircraft would be built.
The only two others that were built after the initial pair were sold to Midland and
Scottish Air Ferries.
These ferries, being painted in a distinctive red and white styling, were used by the company
for a variety of operations, mostly charter flights, but their use was short lived, and
services were suspended in September 1934, after little more than 18 months of operations.
This early curtailment, and the fact that only four Ferries were ever produced, can
be partly owed to the emergence of the new De Havilland Dragon, which very quickly assumed
dominance in the small transport market.
One of the first two ferries, originally built for the air tours, remained unsold all the
way up to 1939.
The other one was sold to the Himalaya Air Transport and Survey company, who used it
for about six or so months before it was destroyed by arson in a hangar fire in 1936.
Throughout the rest of the decade, the remaining ferries would bounce between hangars, owners,
and various uses.
With the outbreak of the second world war, the first aircraft, then currently without
an owner, found itself impressed into service with the Royal Air Force in 1940.
Details are sparse on what exactly it was used for, but it is known that it occasionally
flew about in the latter half of the year, being based out of RAF Halton, and then after
that it served for a time as an instructional airframe.
The third Ferry would also see similar use during the war, but despite their novel appearance,
the decision was not made to preserve any of these weird, little planes, and it appears
that none of them survived past 1944.
This is a bit of a shame, as Airspeed owes its existence to the modest success of these
aircraft, who provided the necessary early income to get their manufacturing facilities
operating and their early reputation established.
Airspeed would continue to have mixed success with its powered aircraft, though this was
often due to poor circumstances rather than poor design, and their most produced airframe
would in-fact be a glider: the A.S 51 Horsa, this featured prominently during multiple
allied operations in the second world war, including operations around Normandy.
As always, thank you all so much for watching, and a big thank you of course to the patreons,
with a special shoutout to Kevin, Delliardo, Bane, FB, Christopher R, Tronathon, Erik Hindman,
John Austin Jr, Ray Culotta, Keith Tarrier, and Greenseaships for their support as wing
commander tier patrons.
Thank you all so much, and I’ll catch you all next time.