Civil Aviation

Handley Page HP.42 “Giant British Airliner”

The Handley Page HP.42 and HP.45, four-engine biplane airliners built by the British Handley Page company, became the world’s largest regularly used airliners upon their 1931 debut.

Responding to a 1928 specification from Imperial Airways, these models were designed with notable similarities: the HP.42 prioritized range over payload.

While the HP.45 reversed these preferences, accommodating more passengers for shorter journeys. Imperial Airways commissioned four units of each variant to be the long-distance flagships of its terrestrial fleet.


The prototype, “Hannibal,” took its first flight on 14 November 1930.

Once integrated into Imperial Airways, these planes became pivotal to its land-based fleet throughout the 1930s, becoming icons alongside the company’s famed flying boats.

Although eight aircraft were built (all with “H” starting names), and three were conscripted into Royal Air Force service during World War II, none survived beyond 1940 due to various accidents.

Handley Page HP 42 at an airfield
Imperial Airways at Cairo. 1932. Note the refueling equipment, including the ladders resting on the upper engines. Also note the modest terminal building.


Initiated by a 1928 Imperial Airways specification for a sizable, long-distance airliner, British manufacturer Handley Page began developing what would become the HP.42.

With a reputation for producing large aircraft, they found the opportunity alluring and created designs accordingly.

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Handley Page designed two closely related aircraft, the HP.42 and H.P.45, to meet different needs: the former for Imperial Airways’ extended Eastern routes and the latter for shorter European paths.

Impressed, Imperial Airways ordered four of each variant. Commonly, the HP.42 was referred to as the HP.42E (E indicating “Eastern” routes like India and South Africa), while the H.P.45 was known as the HP.42W (W representing “Western” or European routes) in service.

The H.P.42 and H.P.45 labels were internal designations from Handley Page and were not widely used during the aircrafts’ operational years.

Attempts have been made to create additional HP.42s for preservation. In 2015, a fundraising campaign aimed to create an HP.42 replica.

Given the lack of surviving models, construction of the replica must incorporate a degree of originality, although authentic blueprints and period materials are available.

While the replica is intended to be airworthy, regulatory safety barriers prevent it from carrying paying passengers.

Innovative Features

The Handley Page HP.42 distinguished itself as a substantial unequal-span sesquiplane, notable not just for its size but also its myriad of innovative features throughout its design.

Handley Page HP 42 Hannibal
Handley Page HP 42 Hannibal – was lost over the Gulf of Oman on 1 March 1940, with eight aboard, including the First World War ace Group Captain Harold Whistler and the Indian politician Sir A. T. Pannirselvam

An assessment by the American National Advisory Committee for Aeronautics (NACA) highlighted several unique elements, including a fuselage that extended further forward beyond its wings compared to most of its contemporaries.

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Adopting an all-metal construction methodology, with exceptions like the fabric coverings on the wings, tail surfaces, and rear fuselage, the HP.42 was divided into two main sections.

The forward section employed a metal monocoque, while the rear was constructed from welded steel tubes, providing notable strength albeit at a relative cost.

The aircraft’s wings utilized a Warren truss for bracing and were equipped with automatic slots on the top wing.

Which benefited from a novel construction technique that employed single z-section spars and planking, both made of duralumin.

It featured slot-type ailerons, mounted on four hinges and supported by four box-section brackets, which were both statically and aerodynamically balanced, ensuring relatively light control.

Spar Obstruction

The lower wings were uniquely designed to slope upwards, inboard of the lower engines, to cross above the fuselage and avoid cutting through it, thereby preserving potential cabin space by preventing spar obstruction.

Cut-away view of the Handley Page 42
Cut-away view

The control for both elevators and ailerons was executed via a large diameter Y-tube, with core controls being duplicated.

Furthermore, the tailplane was designed in a biplane configuration and was equipped with three distinct fins. The HP.42 was equipped with four Bristol Jupiter XIFs engines, each possessing the ability to produce up to 490 hp (370 kW).

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In contrast, the H.P.45 variant was powered by four Jupiter XFBM supercharged engines, each capable of generating up to 555 hp (414 kW).

Bristol Jupiter radial aero engine on display at the Royal Air Force Museum Hendon

Both models positioned their engines identically: two on the upper wing and one on each side of the fuselage on the lower wing, an unusual but not unprecedented configuration, previously seen on Blériot-produced aircraft.

The upper engines were placed as closely together as the propellers’ diameters would allow.

These engines were mounted on sturdy duralumin plates, which were connected to the rear wing spar using welded steel tubing.

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The upper wing housed the fuel for the engines, utilizing a gravity-fed system to supply all four engines.

Throttle controls of the engine incorporated a ‘lost motion’ mechanism, utilizing the initial degrees of movement from the idle position to activate the fuel.

Handley Page HP.42 Had Two Distinct Passenger Cabins

Situated at the aircraft’s very front, the crew compartment was fully enclosed, a feature that was relatively new and unusual at the time.

Cabin of an British Imperial Airways Handley Page HP-42 in 1931.
Cabin of an British Imperial Airways Handley Page HP.42 in 1931.

The HP.42 included two distinct passenger cabins, one situated forward of the wings and another aft. The HP.42E accommodated six (later modified to 12) passengers in the forward compartment and twelve in the aft, with significant space designated for baggage storage.

Conversely, the enhanced HP.42W variant provided seating for 18 passengers in the forward section and 20 in the aft, albeit sacrificing some baggage capacity compared to the earlier model.

Designed with a nod to luxury, the cabins were intentionally styled to mirror the elegance of Pullman railway carriages, akin to those of the Orient Express.

Featuring notable spaciousness, relatively large windows, and comprehensive onboard services to enhance passenger comfort.

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Seatbelts were initially absent from the seating, and only after an unrelated air accident did Imperial Airways introduce this feature.

Furthermore, the low positioning of the doors and the overall fuselage allowed passengers to board and disembark without the need for steps or ladders on the ground.

First Flight of Handley Page HP.42

On November 14, 1930, G-AAGX, which would later be named Hannibal, executed its inaugural flight, piloted by Squadron Leader Thomas Harold England.

By May 1931, it received its airworthiness certificate, facilitating the commencement of commercial operations.

RAF Hendon Airport, London, 1937. Royalty arrives: King George VI, center, and Queen Elizabeth on the aircraft’s steps.
RAF Hendon Airport, London, 1937. Royalty arrives: King George VI, center, and Queen Elizabeth on the aircraft’s steps.

The first flight bearing fare-paying passengers to Paris took place on June 11 of the same year.

Given the elevated cost of air travel at that juncture, passengers typically belonged to the upper echelons of society, including royalty, celebrities, and high-ranking business individuals.

Perceived as the flagships of Imperial Airways, the HP.42/45 fleet, was thus outfitted with exceptional onboard service and a meticulously embellished interior.

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The model earned a favorable reputation among travelers, especially regarding its reliability, and logged a collective fleetwide mileage exceeding 10 million miles during its nine-year service tenure with Imperial Airways.

Imperial Airways demanded its airliners to land safely at low speeds on grass or unpaved airfields. This requirement, differing from conventional airport practices, necessitated a large wing area, similar to a Boeing 767, but with much less weight.

Paris to London

In 1951, Peter Masefield noted the challenges of a slow-moving aircraft with a notably low wing loading, citing its tendency to wallow in turbulent air.

He posited that the substantial reduction in airsickness in contemporary aircraft, compared to pre-war models, significantly contributed to the sevenfold increase in passengers flying to Paris since 1931.

Handley Page 42 airliner ready for a night flight. London’s Croydon aerodrome, 1931.
Handley Page HP.42 airliner ready for a night flight. London’s Croydon aerodrome, 1931.

Another commentator recalled instances of the HP.42 making refueling stops at Lympne during headwind conditions while traveling from Paris to London – its typical cruising speed being 90 mph.

Nonetheless, 90 mph was triple the speed of the former fastest travel mode, involving a mix of steamships and trains. When the HP.42s were retired from civil service on September 1, 1939, they boasted nearly a decade free from significant accidents or fatalities.

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In 1933, confronted with a surge in demand and a simultaneous capacity reduction due to accidents, Imperial sought to acquire two additional HP.42s, intended to be powered by Armstrong Siddeley Tiger engines.

However, price negotiations failed (Handley Page proposed £42000 each, versus the £21000 average in 1931), leading Imperial to opt for two Short Scyllas, landplane variants of the Short Kent flying boat, which could be rapidly integrated into service.

Side Hustle

When not transporting celebrities or business leaders, the HP.42 fleet facilitated popular “flips” over London and Sunday lunch “specials” to Le Touquet, France, for customers desiring firsthand experiences.

These joy rides, including a Le Touquet trip with limousine transfers to central London, were priced just under £4—no small fee considering the £150 average annual wage in 1936. Nonetheless, many individuals saved to experience this glimpse into a lavish lifestyle.

More Orders

Imperial Airways, content with its HP.42s, sought to order two more for 1934 delivery, which was not feasible for HP.

Shorts provided a solution by combining the S.17 flying-boat airliner’s wings, engines, and “tail feathers” with a new, box-section fuselage, creating the 39-seat L.17 landplane.

Khartoum, Sudan. Boarding a handley-page 42 for the flight south.
Handley Page HP.42 at Khartoum, Sudan. Boarding for the flight south. Only one more overnight and then they will be taking in the sights of Lake Victoria.

Named Scylla and Syrinx, these aircraft serviced European routes with HP.42s until September 1939.

The HP.42’s legacy is primarily its safety and reliability, with no fatalities during a fleet mileage of 2.3 million by fall 1939.

Despite its old-fashioned appearance and calm performance, the HP.42 created a lasting impression.

Known for excellent hospitality, supreme comfort, a quiet cabin, and stunning views, it became a symbol of elite travel. Being seen boarding or disembarking an HP.42 was a status symbol for many.

Concorde, the Anglo-French supersonic transport, debuted on January 21, 1976, enjoying a passenger allure akin to the Handley Page biplane that started its airline journey 45 years earlier.

It’s plausible that an elderly Concorde passenger, crossing the Atlantic at bullet speed, might recall HP.42 travels, lamenting the jet’s small windows, tight aisle, and less spacious seats—progress has its nuances.

Who Was Handley Page?

Sir Frederick Handley Page, CBE, stood out as an innovative English aeronautical engineer and the “father” of the heavy bomber.

He earned acclaim for designing groundbreaking aircraft, crucial to efforts in both world wars. In 1942, the crown knighted him for his noteworthy contributions.

Frederick Handley Page
Frederick Handley Page

Initially, Frederick pursued electrical engineering at Finsbury Technical College in Clerkenwell. Subsequently, he furthered his studies at City, University of London.

Frederick was born on November 15, 1885, in Cheltenham, as the second son of Frederick Joseph Page and Ann Eliza Handley.

His parents were Plymouth Brethren, originating from an evangelical Christian movement in Dublin. In 1902, defying his parents’ wishes, Frederick moved to London.

He sought to study electrical engineering at Finsbury Technical College in Clerkenwell. Notably, the City of London’s livery companies established the college, and it was England’s first technical college.

In 1906, Frederick graduated from Finsbury Technical College.

A year later, he joined the Royal Aeronautical Society (RAeS), which holds the distinction of being the world’s oldest aeronautical society.

Aeronautical Experiments

Additionally, RAeS is the only professional body dedicated to the aerospace community. During his time at RAeS, Frederick encountered José Weiss, an artist and pioneer in stable wing glider technology. Weiss, who painted the Sussex landscape, used his earnings to finance his aeronautical experiments.

After his appointment, Frederick left his RAeS post due to misinterpreted experimental work with Johnson and Phillips, seeming like fraud.

Nonetheless, this setback didn’t dampen his aeronautic enthusiasm. In 1909, he founded Handley Page Ltd (HP), initially in a modest Barking factory.

There, using José’s glider wing design, he constructed his first aircraft: the Bluebird.

The company expanded, relocating to Cricklewood factories and producing the world’s initial strategic bombers: H.P.11, H.P.12, and H.P.15. T

hese were the pioneering aircraft, featuring twin-engines and the capability of carrying 815kg of bombs. Thus, Handley Page Ltd emerged as the renowned heavy bomber manufacturer.

In Cricklewood, HP built the Cricklewood Aerodrome near its factories, later transforming into Britain’s largest film studios between 1920 and 1938.

Soon after relocating to Cricklewood, Frederick assumed a role at Northampton Polytechnic Institute (now City) in 1911. He lectured on electrical engineering and established a wind tunnel there.

Presently, City maintains advanced wind tunnels, utilized by its Centre for Aerodynamics and Flow Control for research.

After World War I, Handley Page Ltd persisted in developing military aircraft, constructing the Halifax, a heavy bomber with four Rolls-Royce engines.

Throughout World War II, over 6,000 Halifax aircraft participated, executing 75,000 flights collectively. In 1942, a year post the Halifax’s active duty commencement, Frederick received knighthood for his contributions across both world wars.

From initial steps in Cheltenham to pioneering heavy bombers in two global conflicts, and eventually a knighthood, Sir Frederick Handley Page experienced an illustrious career, spanning fifty years, with City playing a role.