Avro Manchester

[herman1rg]

What if the Avro Manchester was designed from the outset with the Rolls-Royce Merlin and then of course the four engined development of the Lancaster.

Would the need for other two engined mediums been avoided?

 

[Shortround6]

What if the Avro Manchester was designed from the outset with the Rolls-Royce Merlin and then of course the four engined development of the Lancaster.

Would the need for other two engined mediums been avoided?

Not sure when you are talking about.
The class of '36 medium bombers are later in timing to the Vickers Wellington and cousins.
The Class of '36 includes.
Avro 679
Boulton Paul P.91
Bristol P.13/36 (Hercules engines)
Fairey P.13/36 (P.24 engines)
Handley Page HP.56
Hawker P.13/36
Shorts P.13/36
Vickers P.13/36

All of the aircraft design except the ones noted were to use the Vulture engines. 2 had Sabre alternates.
Goals for all was the requirement to carry 8000lb of bombs 2,000 miles and go 3,000 miles with a lighter load.
desired max Cruise speed was 275mph.
There is no way any Merlin being contemplated in 1936-37 could offer that sort of performance so there was no such proposal. Even late war Merlins could not offer the performance desired, max combat is not 30 minute climb performance.

 

[nuuumannn]

What if the Avro Manchester was designed from the outset with the Rolls-Royce Merlin and then of course the four engined development of the Lancaster.

Would the need for other two engined mediums been avoided?

To answer your question about the Manchester, as early as 1937 Avro had considered fitting four engines to the Avro 679 as it was at that stage of development. One idea was to fit Bristol Hercules' to it, although drawings weren't produced until 1939. The decision to convert the Manchester airframe to a four engined aircraft, which required a few changes to the load bearing structure was confirmed in-house at Avro in early 1940 but had been ongoing since 1937. The work was done without an official specification, because the Minister of Aircraft Production had no interest in it, believing its performance would not match the Halifax, which was proving deficient performance-wise in prototype form. Once the prototype of the Manchester Mk.III as the Lancaster was initially designated, an operational requirement was prepared to enable production lines to convert to the new type.

Answering the other part of your question, the twins already in RAF service before the war and early war, the Armstrong Whitworth Whitley and Vickers Wellington were considered heavy bombers at the time. They were not reclassed as medium bombers until the Short Stirling and Halifax entered service. The earlier bombers were developed much earlier than P.13/36, to which the Manchester and HP.56, paper predecessor to the HP.57 Halifax were designed. They were already under development and even if the Manchester had progressed, like the HP.57 as a four-engined bomber, they would have continued in their development line unchanged. At the time that P.13/36 was released, the Air Ministry had also released B.12/36, which Short Bros was offered to contract to build the Stirling.