The History of Armstrong Siddeley and its Associated Companies

For most people, the Armstrong Siddeley name is only associated with motor cars, few if any would expect the Siddeley name to have a connection with aircraft or aero-engines, add in the names Armstrong Whitworth Aircraft, Hawker Siddeley or Bristol Siddeley and confusion abounds! Yet all of these companies are associated through one John Siddeley.

To appreciate how over a period of some 40 years the Siddeley name prevailed, it is convenient to start our investigation as the first World War came to an end. The years which followed would see mergers, take-overs and the creation of new subsidiaries due to market demand and technical developments. Sadly, there would be not a little interference from successive governments, especially in the aero industry and wherever government contracts were involved.

Appointed in 1909 as General Manager of the Deasy Motor Company, John brought the Company into substantial profit and created an organisation to which he was proud to add his name. In June 1915 the now, Siddeley Deasy Company, was awarded one of only five government contracts given for the production of aircraft and aero engines despite being the smallest of those selected. This sudden turn of events caused Siddeley Deasy to expand the workforce and turnover in the most dramatic way. How to replace this volume of business when the Government no longer required 'war work' was now the foreseeable problem. So it was in 1918 most of British Industry found itself with massive overcapacity. Failing to see alternative work for their employees some companies simply closed down their facilities.  Not so John Siddeley, who having already given thought as to how he should prepare for the future took a very different approach. He was convinced there was a future beyond warfare for aircraft and looked around for some other company with whom he could work. 

Sir W.G. Armstrong Whitworth Co. (1897) had during the war years supplied casting to Siddeley Deasy and indeed had been involved in the early days of aircraft construction. However, they held the popular view and decided that there no future lay in continuing with aircraft development. John Siddeley approached this company and suggested a merger as being beneficial to both and persuaded them to continue aircraft production under his management. So it was a deal was struck in May 1919  and the Sir W.G. Armstrong Whitworth Development Co. was formed. Despite the Siddeley Deasy board accepting the agreement, John was not appointed to the board of the Development Company.  


and persuaded them to continue aircraft production under his management.
Late in October 1919 the subsidiary Siddeley Deasy was renamed Armstrong Siddeley Motors to take over the car and aircraft interests of the group with John Siddeley appointed as Managing Director. 

All former aircraft production was transferred from Newcastle to Coventry Parkside. These changes created a stable organisation which proved able to withstand the vagaries of the following years thus ensuring the continuation of employment for many of John Siddeley's workforce and for the few who chose to move south from Newcastle. The new company structure is shown in the attached chart.     

Note ---Change required to chart below.                    

In 1926 John Siddeley became a member of the main board .....Page 62/63 Parkside Story basically here.....................................


Armstrong Siddeley Development company structure looked like this together with future acquisitions.

In 1935 


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