Hinkley Point A was one of three Magnox power stations located close to the mouth of the River Severn and the Bristol Channel, the others being Oldbury, and Berkeley.

[12] The design followed the principles established by the Calder Hall nuclear power station, in that it used a reactor core of natural uranium fuel in Magnox alloy cans within a graphite moderator, all contained in a welded steel pressure vessel.

The gas circulators could be driven by induction motors supplied with mains electricity or, when steam was available, from one of the three 33MWe dedicated variable speed turbo alternator sets (One serving each reactor with one spare).

While primarily planned for peaceful electricity generation, Hinkley Point A was modified so that weapons-grade plutonium could be extracted for military purposes should the need arise.

[13][14] Five 1,050 hp English Electric 8CSV emergency diesel generators were installed at Hinkley Point A, for use in the event of loss of grid supplies.

[16] In August 1963, during a hot run test on the first reactor, which had not then been loaded with nuclear fuel, problems were encountered due to noise from the single stage axial flow gas circulators.

Large sections of the diffusers had broken away, and extensive fatigue cracking was found in the outer tapering shell and central axial cone.

Much pioneering experimental laboratory work on resonance and sound pressure levels was performed at English Electric's Gas Turbine and Atomic Power Division (APD) facilities at Whetstone, Leicestershire, to support the redesign work, and instrumentation to measure stress and sound pressure levels in the gas circuit during testing was developed.

The delay caused severe financial difficulties for the consortium and set the construction schedule back; the station began generating electricity two years late in February 1965.

process was temper embrittled during slow furnace cooling after heat treatment and therefore had poor fracture toughness, i.e. low tolerance of very sharp crack-like defects in highly stressed regions.

At the time of the manufacture of these discs, it was not possible to quantify the effect of embrittlement on the material's ability to tolerate small cracks in the most highly stressed regions.