13 Aug 21
Posted by: Rear Admiral R. G. Melly
Copies are available by contacting the author at [email protected]

From Fellside to Flyplane is a son’s tribute to the remarkable story of his father’s contribution to anti-aircraft fire control.  Iville Porteous’ success in designing and introducing an effective fire control system for the Royal Navy, in the face of official resistance, is indeed inspiring and deserves to be placed on record.  With much of the narrative drawn from Iville Porteous’ personal papers, which now reside in the Churchill Archives Centre, the book details Porteous’ journey from his early experiences in the run-up to the Second World War to the introduction of his Flyplane system, immediately post-war.

Porteous joined the Navy in 1921 as one of the very first naval ordnance artificers, completing his five-year apprenticeship top of his class.  His early appointments and swift promotions meant that he quickly gained an unmatched experience of the early, ineffective fire control system which was based on estimated target movements rather than tachymetric measurements.

Porteous’ opportunity to make a difference came, at the start of 1942, when he was appointed to the Directorate of Naval Ordnance.  This was not entirely by chance, as his presence had been arranged by Lieutenant Commander Larken, with whom he had served four years earlier, impressing him with his intelligence and with his knowledge of fire control and gunnery equipment at sea.

By mid-1942, Larken and Porteous had agreed that there were three priorities to be pursued in addressing the dismal performance of the Navy’s existing fire control system, known as the High Angle Control System or HACS.  The first two priorities would lead to improvements in the existing arrangements, whilst the third priority would build on the earlier work, with a view to developing an entirely new, fully automatic, anti-aircraft fire control system – Flyplane.

The book goes on to explain how Porteous pursued his ideas, working in his own time, with three like-minded colleagues, and in the face of stiff opposition from the Establishment.  He went on to develop a device (the GRUDOU) which produced, automatically and continuously, vertical and lateral deflections, followed by a mechanism to make the line of sight to the target independent of a ship’s movement (the GRU Stabiliser).  Both of these devices were integrated into the HACS, resulting in significant improvements to gunnery, not least because the Americans then agreed to supply the British with their proximity fuzes. The Flyplane system received official sanction in December 1944 and was introduced into service post-war.  Subsequently, the contribution made by Porteous and his small team was recognized with modest cash prizes from the Royal Commission of Awards to Inventors.

The author has produced an engaging account of a remarkable man who, despite his junior rank and a lack of formal education, persisted with his innovative ideas and made a very real contribution to the Navy’s self-defence capabilities.  It is an inspiring story of someone who made a difference – and who, as the author proudly observes, “left footprints on the sand of time”.