Forgotten Aircraft: Avro’s First Bombers (Part 1)

Avro

The name “Avro” is synonymous in aviation circles with excellence in bomber design thanks to two very special aircraft; the World War II-era Lancaster and the Cold War-era Vulcan. Both aircraft captured the public’s imagination and their hearts and both enjoy a strong enthusiast’s following today. While these aircraft are among the greats of military aviation it’s easy to forget that it took Avro a long time to finally get a bomber in to service. In order to reach that goal there were a series of prototypes and experimental warplanes which although showed promise never made it beyond the prototype stage.

Vulcan & Lancaster

One of the world’s first aircraft manufacturers, A.V. Roe and Company was established at Brownsfield Mill, Great Ancoats Street, Manchester, by Alliott Verdon Roe and his brother Humphrey Verdon Roe on January 1st 1910. The great aeronautical mind behind the company was Alliot’s and Humphrey’s contribution was primarily financial and organizational. Alliot had already constructed a successful aircraft the Roe I Triplane but now with the help of his brother he could push forward with his designs. Between 1910 and 1916 the company primarily produced “flying machines” i.e. aircraft for the sake of flying and had no real specified role.

Avro 504Then in 1913 the company took a more serious tone and produced the Avro 504 biplane. Intended as a combat aircraft it was quickly rendered obsolete as the pace of aviation development rocketed but not before three would make history when they set out from Belfort in north-eastern France on 21st November 1914 armed with four 20 lb bombs each. Their target was the Zeppelin works at Friedrichshafen and the aircraft successfully scored several hits inflicting heavy damage by hitting the hydrogen production facility. The raid suffered the loss of one aircraft to ground fire but it was the first time in history that an Avro aircraft was used in an offensive role.

The 504’s useful life as a combat aircraft was short lived although it did see sporadic combat throughout the war but it would be as a trainer that the aircraft would see its greatest use and throughout the 1920s and early 1930s every RAF pilot gained his wings on the 504K trainer. In this role it was a true success story and gained A.V.Roe enough respect to be taken seriously by the Royal Flying Corps (RFC) and the Royal Naval Air Service (RNAS). So when in 1916 the RNAS demanded a long range multi-role combat aircraft to act as a flying escort to its fleet A.V.Roe went to work on his own design to meet the requirement.


Avro 523 Pike

Avro 523

Avro 523 Pike

The resulting design was the Avro 523 Pike, a large twin engined biplane with a crew of three that was powered by two Sunbeam Nubian engines rated at 162 hp each that were arranged in a pusher configuration (facing the tail). The aircraft was expected to provide fighter escort for the fleet against Zeppelin airship attacks, provide reconnaissance for the fleet and offer a true offensive capability with a bombload of 225lbs (just 15lbs less than the entire complement of bombs dropped by the Avro 504s in 1914). This was a tall order for any aircraft manufacturer whose trade was barely in its teen years.

The design of the aircraft was very contemporary. It was a rather large biplane design with its engines mounted on spars between the upper and lower wings. The crew of three were seated in three open cockpits with the pilot in the centre flanked by a bomb aimer/gunner in the nose and a defensive gunner just behind in the dorsal position. The fully skinned fuselage was rectangular in shape but blended rather attractively throughout its entire length.

Unfortunately results showed that while the aircraft had excellent endurance, around seven hours when flown economically, the rest of the aircraft’s performance was disappointing. The Admiralty assessment said that the aircraft would soon be surpassed by the newer aircraft then in development which offered superior performance. A second prototype was completed with Green E.6 engines and was given the in-house number 523A but the engines offered even lower performance and no production order was placed. The two prototypes would continue on as test aircraft with Avro however.

SPECIFICATIONS (Avro 523)

  • ENGINE: 2 x 160hp Sunbeam Nubian in-line
  • MAX SPEED: 97 mph
  • WINGSPAN: 18.29 m (60 ft 0 in)
  • LENGTH: 11.91 m (39 ft 1 in)
  • HEIGHT: 3.55 m (12 ft 8 in)
  • WING AREA: 75.71 m2 (814.93 sq ft)
  • TAKE-OFF WEIGHT: 2751 kg (6065 lb)
  • EMPTY WEIGHT: 1814 kg (3999 lb)
  • ARMAMENT: 2x .303 Lewis Mchine guns
    225lbs of bombs

Avro 529

Avro 529

The RFC had shown interest in the 523 but like the Admiralty were too concerned with its impending obsolescence in the face of other newer types then in development to place an order. A.V.Roe was undeterred however and he believed that with some development work the 523 could become a war winning aircraft. After the Admiralty declined to order the 523, Roe managed to convince them to fund two prototypes of an improved version.

The resulting Avro 529 was a generally enlarged version of the 523 Pike but incorporated several noteworthy improvements. The most obvious change was the switch to tractor propellers as opposed to pushers as on the 523. These were turned by far more powerful Rolls-Royce Falcon engines that produced 190hp each however this was not enough to counteract the greater weight of this larger aircraft and the result was that the 529 had performance generally inferior to its predecessor. This forced A.V. Roe to promptly finish work on a second prototype powered by 230hp Galloway engines and this improved all round performance. A less obvious change was that the tail on the 529 had also been moderately redesigned.

Other innovations that came with the aircraft was the ability to fold the wings back from a point just beyond the engine mounts indicating that it could be used in some shipboard capacity if the Admiralty renewed their interest. A.V. Roe and his team displayed their genius with the 529 by taking far more consideration of how the three man crew would function under battlefield conditions; something that was barely given a second thought in other designs of the period. The bomb aimer who sat up front was provided with a Gosport tube communication device allowing him to yell instructions back to the pilot so as to help with aiming. The rear gunner was also given duplicate controls so if the pilot became incapacitated the plane would not necessarily be lost.

The 529 displayed good flight characteristics in all areas except the longitudinal plane. This could have been easily rectified with yet another redesign of the tail section but the Admiralty was growing impatient and refused to commit themselves any further. As though history repeated itself, the 529 shared an almost replicated life of its 523 forebear there being two prototypes both of which were powered by different engines and both of which ended their days as trial aircraft.

SPECIFICATIONS (Avro 529)

  • ENGINE: 2 x 190hp Rolls-Royce Falcon
  • MAX SPEED: 93 mph
  • WINGSPAN: 19.20 m (63 ft 0 in)
  • LENGTH: 12.09 m (39 ft 8 in)
  • HEIGHT: 3.96 m (13 ft 0 in)
  • WING AREA: 85.70 m2 (922.50 sq ft)
  • TAKE-OFF WEIGHT: 2862 kg (8309 lb)
  • EMPTY WEIGHT: 2148 kg (4736 lb)
  • ARMAMENT: 2x .303 Lewis Mchine guns
    1000lbs of bombs

Avro 533 Manchester

avro 533 Manchester

The Avro 533 Manchester was the ultimate expression of Avro’s World War I bomber concept. This was yet a further development of the 529 incorporating all that aircraft’s improvements over the 523 and then expanding on them. Design work began in 1917 and originally the aircraft was to be given the number 529B but the changes proved so extensive that it warranted its own number becoming the 533 before adopting the name Manchester (not to be confused with the later Avro Manchester, the Lancaster’s forebear). The 533 Manchester was similar to the 529 but with some subtle changes. Overall the aircraft was marginally smaller and featured a raised centre fuselage roof, a glass window for the bomb aimer and attractive smoothed over engine cowls.

At the time a number British aircraft manufacturers were instructed to design their planes around the Dragonfly radial engine then in development which promised 320hp; nearly twice the power of the 529’s Falcon engines. The Dragonfly ultimately proved to be quite the developmental nightmare and this stalled many of the aircraft under development that was relying on it. With time pressing on and afraid of losing out yet again, Avro installed the 300hp Siddeley Puma engine in the first 533 Manchester prototype as a stop-gap and to allow flight testing to begin but the Dragonfly’s delay had hurt the program badly and by the time the Puma engined aircraft was ready the war was over.

Orders for any aircraft then under development were cut back dramatically and Avro was not promised any firm order for the Manchester. A.V.Roe optimistically pressed ahead with development hoping that the newly established Royal Air Force would see its potential and want to build its post war bomber force on the type but despite the arrival of the long overdue Dragonfly engines in 1919 the program was effectively dead as far as RAF procurement was concerned. A.V. Roe put forward plans for a passenger version but these too were shelved.

It was a sad end to a promising design lineage.

SPECIFICATIONS (Avro 533 Manchester)

  • ENGINE: 2 x 320hp ABC Dragonfly radial engines
  • MAX SPEED: 115 mph
  • WINGSPAN: 18.29 m (60 ft 0 in)
  • LENGTH: 11.28 m (37 ft 0 in)
  • HEIGHT: 3.81 m (12 ft 6 in)
  • WING AREA: 75.90 m2 (817.00 sq ft)
  • TAKE-OFF WEIGHT: 3352 kg (7390 lb)
  • EMPTY WEIGHT: 2217 kg (4887 lb)
  • ARMAMENT: 2x .303 Lewis Mchine guns
    880lbs of bombs
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8 responses to “Forgotten Aircraft: Avro’s First Bombers (Part 1)

  1. Pingback: Forgotten Aircraft: Avro Manchester | Defence of the Realm

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  3. Pingback: Boulton Paul P.29 Sidestrand & P.75 Overstrand | Defence of the Realm

  4. Pingback: Forgotten Aircraft: Avro’s First Bombers (Part 2) | Defence of the Realm

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  6. Pingback: Forgotten Aircraft: Avro’s First Bombers (Part 3) | Defence of the Realm

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