Developments in Air
Traffic Control
Control was carried
out from the second floor of the tower, the Navy 'Watch
Office' on the roof not appearing to be used operationally. At first Control
was by M/F and VHF radio, with ground direction finders and radio
reports from aircraft being the only means of determining aircraft positions.
Flight Progress strips came into use in this era showing aircraft details
and control instructions issued. The M/F services including the direction
finding station (on March 1st 1951) were withdrawn from use, as more aircraft
were equipped with VHF radios. Right at the end of the decade, in 1959,
the new Control Room was installed on top of the Navy Watch Office, resulting
in some major modifications to the internal structure. Also in this period
a former Royal Navy FV5 VHF direction finder was installed, bringing near
instantaneous bearings on aircraft transmissions into the control room.
Previously they would have been passed on paper slips from the D/F operator
in the room behind control
  
     
Operations and facilities
in 1951
Based on some local
charts and text pages from the RAF Radio Facilities Charts book dated 31st
December 1951.
'Airways' had been established
in 1950 for positive control of en-route aircraft, 'Red Three' going overhead
the Isle of Man between Liverpool and Belfast. A 'radio-range' had been
installed at Cregneash, operating on 391 Khz with an identification of
'MYI' This radiated four 'legs', towards Belfast, Wallasey, Dean
Cross (Cumbria) and Dublin with associated VHF 'Fan Markers' at Wallasey,
Dean Cross and Portaferry (N. Ireland). The radio range transmitted audio
morse code 'A - .' and 'N .
-' letters. iI the aircraft was left of track the pilot
would here the letter 'N' in his headphones, if right of track the
letter 'A'. When on track they would merge to a continuous tone. It must
have been quite tiring! There was also an non directional beacon (NDB)
at Cregneash 'GCF' on 312.5 KHz, which was more for marine use, operating
as part of an Irish Sea network on the same frequency, transmitting according
to a set timetable.
Ronaldsway
ATC
Ronaldsway is shown
equipped with an NDB 'GJE' (the old w/t radio callsign for Ronaldsway)
operating on 322 KHz and SBA 'Standard beam Approach' on runway 27, also
coding 'GJE', operating on 33.3 Mhz with an Inner Marker beacon on 38 MHz.
SBA was a development of the pre-war 'Lorenz' approach aid developed in
Germany and installed at Croydon Airport in the 1930s. SBA gave similar
indications to the radio range, providing what we now know as a Localizer
approach to the runway. It also provided a rudimentary glideslope indication
on a cockpit instrument, the pilot choosing which of several paths to follow
down. The approach would commence overhead the 'GJE' NDB and an outbound
leg would be flown away from the airfield, descending to a intermediate
height. After a set time period, probably 2 minutes, an inbound turn would
be commenced to establish on 'the beam' before commencing a final descent
until the airport came into sight. The inner marker beacon was situated
inside the airport boundary and indicated imminent arrival over the runway
threshold. There would have also been approaches published based on the
GJE NDB for both runways 27 and 09.
For communications,
Ronaldsway is show having HF radio on 3255 KHz, with Approach Control on
VHF 119.7 MHz and Tower on 118.7 Mhz. Also available was 121.5 MHz (Civil
Emergency) and 116.1 MHz (Military Emergency. VHF Direction finding was
available on 119.7, 121.5 and 116.1. In the 1950s an Instrument Landing
System was commissioned on runway 27. This gave pilots an accurate indication
of both lateral (Localizer) and vertical (Glidepath) position on final
approach, displayed on a Course Deviation Indicator instrument in the cockpit.
The Localizer aerial was at the far end of the runway with the Glidepath
aerial by the side of the runway close to the touchdown point. An Outer
Marker beacon was installed on Santon Head, with the Inner Marker inside
the airfield boundary. With this precision system, landings could be accomplished
in much poorer weather conditions than before.The SBA continued in operation
for non ILS equipped aircraft.
   
Area Control
The new Airways were
controlled from Preston Air Traffic Control Centre at Barton Hall, one
of three civil units established in the UK, the others being Scottish,
at Prestwick and Uxbridge in London. Preston used VHF 119.3 KHz (with HF
3270 KHz as backup) for all its airways, with VHF 118.5 KHz and HF 5692
KHz available for Flight Information Service. The Flight Information
Service was the natural follow on from the old 'Communication Areas' and
would provide weather and airfield details together with information on
other aircraft know to be operating outside controlled airspace. Area Control
within the airways was by 'procedural' means, with separation being either
vertical or lateral, using time intervals between aircraft, proved by aircraft
reports over defined 'reporting points'. The RAF had their own Control
Centre at Preston for control of military aircraft. Weather reports and
forecasts for Ronaldsway (and other northern airports) were broadcast from
Preston on frequencies 404.4, 3953 & 8942 Khz, the forerunner of the
present VOLMET and ATIS services.
New Control Room
(1959)
At the end of
the decade a new control room was built on top of the old RN Watch Office.
This provided accommodation for the Aerodrome Controller, Approach Controller
and the Air Traffic Control Assistant. For the first time all of the airfield
and surrounding airspace could be seen from one location, without having
to walk outside onto a balcony! The former Control Office was vacated and
used by Air Traffic Engineering to house the ever increasing amount of
technical equipment.
Below are external plans
of the control tower for before and after the new Control Room and two
internal plans of the tower layout before the new control room was installed.
   
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