THE TRANSMISSION GALLERY
|Photos by Various||Page last updated: 2023-05-31|
|On 10 August 2021 a fire broke out in one of the transmitter buildings close to the base of the mast. The onsite engineer called the fire brigade at 1319 stating that he could see smoke coming from below the first stay level, around 50 - 60 metres from the ground. A local hill walker also noticed a huge black cloud of smoke coming from one of the buildings at the base of the mast, with smoke coming out of the top "a bit like a chimney".|
Eight pumps from North Yorkshire Fire and Rescue Service attended and "worked to control the fire in difficult circumstances and extinguished a fire in a single-storey stone building and transmitter mast." Only one of the four buildings at the mast was affected.
The fire took all services off air. Survey work was undertaken by drones to ascertain structural stability, and a 300m exclusion area was put in place. The mast was subsequently deemed structurally unsound and was demolished on 6-Oct-2021 (see video link at bottom of page).
All services, including digital TV, DAB, BBC national, BBC local and commercial FM radio were put off air for a considerable period. Bilsdale is an important site, providing over 1 million people with TV and radio services in an area stretching from Hartlepool in the north to York and Harrogate in the south, most of North Yorkshire, including Stockton, Middlesborough and Whitby.
In order to restore services to as many people as possible as quickly as possible, emergency work at the Eston Nab relay was immediately undertaken. On 11 August the three TV PSB transmitters were retuned from their normal allocations of 23/26/48 to the Bilsdale allocations of 27/24/21, the transmit log periodic antennas were changed from vertical to horizontal polarisation, the receive (RBL) antenna was swung around to point at Pontop Pike, and the transmitter powers were doubled from 10W to 20W. This action restored PSB services to viewers in Hartlepool, Redcar and the eastern edges of Middlesbrough, although all viewers who were using Eston Nab prior to this change then needed to retune their equipment. Subsequently on 12 August a temporary mast and additional transmitters were installed, allowing the PSB services to be transmitted at higher power over a larger area on the Bilsdale channel allocations. The existing Eston Nab transmitters were then tuned back to their original allocations and repurposed to broadcast the three COM services. It was not possible to use the Bilsdale allocations for the COM services as they are adjacent channel to the incoming feed from Pontop Pike. Transmissions from the temporary mast were increased in power on 19 August extending coverage to over 250,000 households. Radio services for Radio Tees (95.0 MHz) and TFM Radio (96.6 MHz) were installed on 11 & 12 August, and the other commercial radio services were then added on 13 August: Heart FM (North East) on 100.7 MHz, Capital FM (North East) on 106.4 MHz, and Classic FM on 101.6 MHz, thus restoring all local radio services to the majority of their previous audience. Although Eston Nab was originally primarily a low power television relay, the FM radio installation covers a wide area, including Hartlepool, Stockton, Middlesborough, Guisborough, Darlington and Scotch Corner. On 17 August DAB services for Digital 1 and SDL were also added.
A temporary 15m mast was erected at the BT Microwave site at Arncliffe Wood on 20-Aug-2021, with transmissions commencing later that same day. This measure restored reception to the areas around Darlington, Barnard Castle, Richmond, Leyburn, Catterick, Masham and Ripon. PSB services were initially on channels 40, 43 & 46, but from 13-Oct-2021 they were changed to channels 29, 31 & 37 when the temporary mast at Bilsdale Quarry came into service.
A temporary site at Sutton Bank commenced transmissions on 8 September extending coverage to Northern parts of York, Harrogate, Pickering, Ripon, Masham and Leyburn. PSB services were on channels 27, 24 & 21. This was discontinued on 13 October when the temporary mast at Bilsdale Quarry came into service.
TV services at Bilsdale's biggest dependent relays Whitby, Guisborough and Limber Hill were restored on 13-Aug-2021, either by changing the RBL from Bilsdale to Pontop Pike, or in the case of Whitby for PSB 1 & 3 by changing the feed to D-Sat 27.5W. The same is also likely to have happened at Guisborough. BBC Tees on 95.8 MHz from Whitby, which was also dependent on Bilsdale, was also restored. Services from Peterlee were restored on 18 August, again by changing the incoming feed to Pontop Pike. Skinningrove was put back on the air on 20 August, initially only the PSB2 multiplex with the other PSB services following shortly after.
The remaining Bilsdale relays were gradually restored by changing their RBL feeds to Pontop Pike or satellite. This was completed on 3rd September when the Rosedale Abbey relay returned to air. A temporary transmitter has also been added for Radio Tees on 104.0 MHz at Darlington (Patches Lane) also known as Beaumont Hill. This covers Darlington and surrounding areas.
The next stage of recovery was to install a temporary mast at Bilsdale Quarry, just to the south of the main Bilsdale site, which restored TV services to about 95% of viewers. A 80m mast was erected at a nearby disused quarry site, and despite some initial delays due to the legal/planning process and bad weather, transmissions from this site came into service on 13-Oct-2021. This mast remained in service until a second more substantial tower (also 80m in height) was built. Planning consent for Bilsdale Tower was granted on 25-Oct-2021 and TV transmissions were transferred from the quarry site on 23-Feb-2022. The Bilsdale Quarry mast was not designed to survive the harsh winter conditions on the moor as it was not that substantial and the stay anchors were only concrete blocks resting on the ground.
These works are no simple endeavour, given that the area is a Site of Special Scientific Interest which is valued for a mix of habitats of rare fauna and flora. Ground needs to be prepared, power cables run, temporary transmitter units and feeders installed. It should be borne in mind however that the replacement structures were 240m shorter than the felled mast, so a reduction in coverage area was inevitable. The extent of this reduction was assessed, and Arqiva published a map showing the areas predicted still to have no signal when Bilsdale Quarry was in service.
The areas shown in red remained unserved by the temporary mast and tower. This includes areas on the coast, the Dales of North Yorkshire and County Durham, and some other areas. Consequently several temporary transmitters were installed by Arqiva to serve many of these areas, together with modifications to some of the existing Bilsdale relays.
30-Oct-2021 Loftus temporary transmitter in service
31-Oct-2021 Thirsk temporary transmitter in service
29-Nov-2021 Kirkbymoorside temporary transmitter in service and a horizontally polarised beam added at Bainbridge
3-Dec-2021 Ripon temporary transmitter in service and a horizontally polarised beam added at Castleton
14-Dec-2021 Masham temporary transmitter in service
21-Dec-2021 Leyburn temporary transmitter in service
23-Dec-2021 Helmsley temporary transmitter in service
14-Jan-2022 A horizontally polarised beam added to the Pontop Pike relays at Seaham and Sunderland
8-Mar-2022 Northallerton temporary transmitter in service
26-May-2022 Blackhall Colliery temporary transmitter in service
The final phase is the restoration of a service approximately equivalent to that prior to the incident. The fire damaged mast was demolished on
6-Oct-2021, see the link at the base of this page for a video of the demolition. Arqiva submitted a planning application with North Yorkshire Moors Planning on 16-Dec-2021 for the construction a 306.2m high lattice mast which was approved on 18-Feb-2022. Planning application NYM/2021/1004/EIA Construction of the new mast was completed in the spring of 2023 with TV services going live on 22-May-2023.
|Image credit: DB Aerial & Satellite, Hartlepool|
The remaining pictures were taken by Martin Brown on the 20th August 2021, 10 days after the fire.
|Starting at the bottom|
|The first stay level|
|This is the area southwest of the main site, where the temporary mast was to be sited. Just a solitary digger on the site on the afternoon of Friday 20th.|
Bilsdale mk1 index
Arqiva Bilsdale update 8-Sep-2021 (YouTube video)
Arqiva Bilsdale update 17-Sep-2021 (YouTube video)
Bilsdale Mast Restoration - Exploring The Technicalities
Bilsdale Incident: Temporary Mast Construction
Mast demolition 6-Oct-2021 (YouTube video)
Bilsdale fire - Ofcom review
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