Mapping Mountains – Trimble Surveys – Beacon Hill

 

17.07.21  Farrington Bank (SO 305 699) 

Farrington Bank (SO 305 699) and the Spaceguard Centre

I’d visited Farrington Bank previously and when last there, Trimbled its summit.  This hill is classified as a Pedwar and the Trimble survey de-twinned it from its adjacent summit positioned beside the observatory at the Spaceguard Centre.  Each summit is given a 417m spot height on contemporary Ordnance Survey 1:25,000 Explorer maps. 

On my last visit the summit area of Farrington Bank consisted of a closely cropped grazing field.  Today it was awash in breeze blown barley.  Prior to visiting I had contacted the Spaceguard Centre and gained permission to park and visit the triangulation pillar which is placed at the rear of the observatory.  This is close to where LIDAR gives the high point of this part of the hill, which is beside a fence and picnic table a few metres from the trig pillar.  Although the summit of Farrington Bank is higher, it is always worthwhile visiting the other top, purely as having an observatory so near the top of a hill is an experience in itself. 

I left my car parked on a flat area of land at the end of the track leading to the access gate to the upper field of Farrington Bank.  Beyond the gate was barley, which was a surprise as I expected the same closely cropped grass that I encountered on my last visit. 

Following the vehicle track through the barley on Farrington Bank

Looking toward the summit of Farrington Bank

Heading through the barley were a number of vehicle tracks, these we followed until close to the high point, which was only a short detour to get to.  Recently I’d visited a summit on the outskirts of Meifod planted in wheat.  Again a vehicle track led close to this hill’s high point and again the wheat swayed in unison with a cooling breeze.  Today the barley did likewise, it was softer than the wheat and gave a gentler feel and formed a lush crop that meandered across the hill swaying this way and that, all greened with emerald touches accentuated by the afternoon light.  It was wonderful to walk through. 

Approaching the summit of Farrington Bank

Crossing the summit of Farrington Bank

Afterward we visited the other top leaving the car in the small parking area for the observatory, and the woman who I had spoken to on the phone came out to greet us.  She told us the history of the observatory and its purpose, before we sauntered around the side of the building to visit the high point beside the fence and picnic table and then the trig pillar at the rear of the building. 

The Spaceguard Centre

Once back at the car I drove down the narrow lane to Knighton and then up the B4357 and turned on to the B4355 where I parked in a convenient lay-bi beside the road.  This gave easy access to Hawthorn Hill (SO 287 677); a Pedwar whose summit was about a mile away.  I was tempted to join Aled, but as I had visited the hill and as the heat was still uncomfortably warm I remained at the car and waved Aled off watching him disappear down the track over the connecting bwlch and out of sight up the hill. 

Aled heading off toward Hawthorn Hill

The ascent didn’t take him long.  I was happy enough waiting at the car, which was parked in shade.  I changed in to dry clothes and luxuriated in getting my walking boots off, cooling down and taking on lots of liquid.  It was good to just stop and do little.  I watched sheep doing the same in the opposing field, some hardened souls still munched in the sunlight, but the majority were slumbered down lying in shade.  It had been another good day on the hill with lots achieved.  It had also been an exceedingly warm day on the hill, with what we did just enough to enjoy and not too much to hinder. 

 

Survey Result: 

 

Farrington Bank (significant name change)

Summit Height:  416.7m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)

Summit Grid Reference:  SO 30500 69937 (from previous Trimble GeoXH 6000 survey) (summit relocation confirmed)

Bwlch Height:  c 294m (interpolation)

Bwlch Grid Reference:  SO 27464 69909 (interpolation)

Drop:  c 123m (Trimble GeoXH 6000 summit and interpolated bwlch)

Dominance:  29.52% (Trimble GeoXH 6000 summit and interpolated bwlch)

 

 

For details on the survey of Farrington Bank

 

For further details please consult the Trimble Survey Spreadsheet

 

 

 

 

 

 

Mapping Mountains – Trimble Surveys – Beacon Hill

15.02.18  Farrington Bank (SO 305 699)

Farrington Bank (SO 305 699)

There is a certain form of fulfilment when de-twinning twinned tops, these are the hills that according to map spot heights have summits of the same height and are adjoined to one another via a direct connecting bwlch.  Farrington Bank is such an example as it has two summits, both of which are given a 417m spot height on the Ordnance Survey 1:25,000 Explorer map.  They are aligned north-east to south-west of one another, with a conifer plantation between.  The north-east summit is crowned by a trig point given a 416.960m flush bracket height in the OS Trig Database and which is situated at the back of buildings that accommodate The Spaceguard Centre which is an observatory giving itself the moniker of The National Near Earth Objects Information Centre, whilst the 417m south-westerly summit is positioned in a closely cropped grazing field.

With an appointment to meet friends in Newtown at 6.00pm and wanting to survey the critical col of The Warren after these two tops I could not linger, so I drove up the partly rough track that leads to the observatory and parked on the grass beside the continuation of the track which gives access to the centre’s car parking area.

Leaving the car the chilled wind blew from the west, from where masses of dark winter shower clouds had, and were still, rolling in depositing sleet, snow and rain as they did so.  I’d been fortunate during the day and only experienced one snow flurry but the one now massing looked to be the largest of the day so I quickly walked toward the large field where the summit of the south-west top is situated.

I placed my rucksack where my initial preference was for the high point and quickly assembled the Trimble on top, measured the offset between its internal antenna and the ground at its base and waited for five minutes of data to be gathered and stored.  During this I had time to assess the placement and decided to take a second data set a few metres from its present position.

Gathering data at the summit of Farrington Bank

As I gathered this second data set the mass of murk forever pushed nearer and by the time I had closed the equipment down the sun had disappeared and the edge of murk was directly above, I quickly packed the Trimble away and headed back to the track and up to the observatory.

Dark clouds massing

As I walked up the access track a number of people were leaving the building, they had just had a conducted tour of the observatory, so I knocked on the door, introduced myself and asked if I could visit the trig pillar at the rear of the buildings and explained what I wanted to do.  The woman who worked at the observatory seemed pleasantly surprised that I had asked and thanked me for doing so, we chatted for a few minutes in the warmth of the building before I ventured out to have a look at the land beside the trig.

The Spaceguard Centre

The trig pillar is placed close to the side of one of the buildings and is housed in a small fenced compound that also has two picnic benches with accompanying seats.  I judged the high point of this summit was at or near to the base of the trig pillar and set the Trimble up on its top.  Thankfully it only took a couple of minutes for the Trimble to attain the 0.1m accuracy level before data should be logged, and when it did so I pressed ‘Log’ and scampered behind the side of one of the buildings out of sight of the surveying equipment and on the leeward side of the snow flurry that was now skimming across the land.

Gathering data at the north-east and lower top of Farrington Bank  

Once five minutes of data were collected I switched the Trimble off and headed back to the entrance door to express my thanks to the woman from the observatory before walking down the track to my car, only one survey for the day now remained; the col of The Warren. 

Survey Result:

Farrington Bank (significant name change)

Summit Height:  416.7m (converted to OSGM15)

Summit Grid Reference:  SO 30500 69937 (summit relocation confirmed)

Bwlch Height:  c 294m (interpolation)

Bwlch Grid Reference:  SO 27464 69909 (interpolation)

Drop:  c 123m (Trimble GeoXH 6000 summit and interpolated bwlch)

Dominance:  29.52% (Trimble GeoXH 6000 summit and interpolated bwlch)

For details on the 2nd visit to Farrington Bank

For further details please consult the Trimble Survey Spreadsheet