for calculating the Threshold QFE for various runways at Ronaldsway. Most
aircraft in thos days landed using the QFE pressure setting, so that the
altimeter indicated 0 feet on the ground. Because the various runway threshold
differed in elevation, ATC would calculate the required QFE for each runway,
based on the Airfield QFE supplied by the Met Office and rounded down to
the nearest whole Millibar. Note use of the 'Q' code still, QFU = Runway
- or in the words of the 1937 Air Ministry book of 'Q' codes 'The Prescribed
Direction of Landing, expressed as the Magnetic Course to Steer'