Post by aerofoto - HJG Admin on Apr 5, 2022 10:33:57 GMT
Not sure that the RAF COMET II's could operate in those conditions, but, the RAE COMET IIIB (XP915 .... available here at HJG as part of the DMFS collection) most certainly could, and did, being used to flight test auto-approach/landing equipment in reduced visibility .... in advance of the HS TRIDENT's entry to service.
From my recent COMET history ....
Beyond its civil development and evaluation G-ANLO then entered a new phase in its flight testing career. During June 1961 the aircraft joined the RAE (re-registered XP915). Here it acquired a distinctive nose probe/antennae and was first used to perform blind landing experiments during the development of auto-land systems intended to aid reduced visibility approaches. XP915 was then transferred to the BLEU to perform high-speed runway braking tests to analyze the effectiveness of a variety of developmental retardants aimed at assisting the deceleration of aircraft with braking and undercarriage difficulties. The aircraft was finally withdrawn from RAE service during 1973. It was then transferred to RAF Woodford during 1978 for AEW3 NIMROD development where it underwent extensive airframe modification.
"My weather" was fog with 800 m visibility, better than "200 and a half" for a CAT I ILS. The early Comets already had the Sperry Zero Reader onboard, which was intended to lower the ILS minimum to 100 ft.
The difference of its working to an ILS indicator was to show if you were correcting well and not only how far off from localizer and glideslope you were:
Bad luck, that nobody seems had simulated the Zero Reader for FS, so one has to use an old HSI instead.
It resembles another Sperry Zero Reader out of the F-86 fighter jet, which was a step further combing the Zero Reader with the HSI.
BUT: also the FS HSI (out of the SCS Tu-134) does not give the steering command, which internally gives an AP.
Old and experienced pilots had some difficulties to come to terms with the early FD systems as the FD did not free them (as was promised) from crosschecking the FD commands with the raw datas of ILS, attitude, heading, altitude, speed and vertical speed.