Tuesday, 9 June 2015

G&J Surveys - Meall Gaineimh - UKHillwalking Article

UKHillwalking have published an article on the survey of Meall Gaineimh conducted by G&J Surveys.  The original article and a link to it on the UKHillwalking website appear below.
Meall Gaineimh was surveyed as a potential new Munro Top with members of The Munro Society (TMS) and representation from the Scottish Mountaineering Club (SMC).

Exclusive: Meall Gaineimh - A New Munro Top?
by John Barnard, Graham Jackson & Myrddyn Phillips 09/Jun/2015

G&J surveys, the amateur team behind several revisions to the Munro list and the addition of new mountains to England and Wales, recently travelled to the eastern Cairngorms to establish the true height of Meall Gaineimh, an obscure satellite peak of Ben Avon. Would it prove to be a new Munro top? The short answer is no. This account, written exclusively for UKHillwalking, explains how they reached that result.

As the high plateau of the Cairngorms descends north-east over Ben Avon, it culminates on Meall Gaineimh, before rolling down to meet the Builg Burn and River Avon. This north-easterly land is typical of the Cairngorms with hills of heather and attractive granite tors. It was the tor at the summit of Meall Gaineimh that interested us as this upthrust of rock is higher than the hill’s cairn which is positioned just under 100 metres away on the rounded summit plateau.
Meall Gaineimh from the approach to Inchrory

This cairn has a 912m spot height beside it on Ordnance Survey maps. The survey method of photogrammetry that produced this spot height has a +/-3m margin of uncertainty associated with it, which means that the hill could be between 909m – 915m in height. However, that is to the ground beside the cairn which we knew to be at least 2m lower than the top of the granite tor. Consequently, there was a good possibility that Meall Gaineimh could be over 914.4m high; the metric equivalent of 3,000ft.
The survey of Meall Gaineimh had been arranged in appreciation of Iain Robertson, who was the past President of The Munro Society (TMS) and the person who conceived the Society’s “Heightings Project”. The aim of this project was the accurate survey of all those hills that are close to the 3000ft Munro qualification. This programme has now finished, but the detailed surveys carried out in this project have reduced the number of Munros from 284 to 282. With verification by Ordnance Survey who process the GNSS data we collect, the Scottish Mountaineering Club (SMC) has accepted the results and subsequently re-classified Sgurr nan Ceannaichean and Beinn a’Chlaidheimh from Munro to Corbett status.
When Sir Hugh Munro compiled his list of the Scottish 3000ft mountains he included subsidiary tops, known as Munro Tops, and there are an additional 227 of these. This figure has recently changed, as it had stood at 228, but our survey of Knight’s Peak on Pinnacle Ridge of Sgurr nan Gillean in the Cuillin of Skye proved that its height was just below 3000ft.
Graham beside the Leica GS15 on the summit tor of Meall Gaineimh

The survey of Meall Gaineimh was arranged for Wednesday 27th May with a number of TMS members present and the SMC being represented by Rab Anderson, who is the Editor of the SMC Hillwalkers’ Guides, which includes their guidebook ‘The Munros’.
We met at the parking area below Corgarff Castle near one of the entrances to the Balmoral Estate, having obtained permission from the Factor to drive as far as Inchmore. This helped greatly by reducing the overall length of the walk. As the weather forecast from mid-afternoon was for a deepening low pressure system to arrive from the west with rain and strengthening wind, our timing on the hill was paramount and if the survey could be completed before the worsening weather arrived, it would prove beneficial to say the least.
We had come well prepared with all necessary surveying gear and set off walking at 9.10am following the track from Inchmore, as it contours around the northern ridge of Cairn Culchavie, before leaving the Balmoral Estate and entering that of the Sultan of Brunei.  From here we descended to the Builg Burn and River Avon. Beyond lay the heathery mass of Meall Gaineimh rising above with a good stalker’s path leading up its northern flank.
Thankfully the predicted 30-40mph winds had not materialised by the time we arrived at the summit, and with the hill clear of mist or cloud we could use the optical level and staff to pinpoint the highest point of the summit tor and take readings farther afield to the ground at the base of the cairn.  The latter proved 2.7m lower than the top of the granite tor.
The Leica GS15 on the summit tor of Meall Gaineimh with some of the team sheltering below

As the high point of the tor was directly over a 4m vertical drop, we positioned the Leica GS15 receiver on a tripod a safe distance from the edge and took a measurement offset from its set-up position to that of the highest point. Although the winds were generally light, there were occasional gusts and therefore we placed a number of rocks around the legs of the tripod to safely secure it.
Once the equipment was switched on, a long wait now commenced, as for Ordnance Survey verification of the result a minimum of two hours of data are required. The eastern side of the tor proved ideal as a shelter from the chill of the westerlies that were increasingly blowing in.
Before the two hour data set was complete, we also took a reading with a Trimble GeoXH 6000 receiver on the actual summit and also at the bealach. Although this instrument is not as accurate as the Leica GS15, it produces data that is more accurate than that on a map and only requires a five minute collection time to do so. This would give us a combination of data sets and a value for the hill’s drop and a ten figure grid reference for the actual summit and the bealach.
If Meall Gaineimh proved to be at or over 914.4m /3000ft, we knew that the drop value would not be a pre-requisite for determining its status, as the SMC would probably take other factors into account also. But with a substantial granite tor at its summit, which added appeal to its aesthetic value, and a direct distance of 1.25km to the nearest Munro Top and 5km to the nearest Munro, we were optimistic that Munro Top status would be granted if Meall Gaineimh proved to be over 914.4m/3000ft in height.
The Leica GS15 gathering data on the summit tor of Meall Gaineimh

Once the two hours of data were gathered, the equipment was switched off and packed away. We then descended back along our inward route, with the westerly murk bringing the forecast rain during the last hour of our walk.
The data was duly post-processed yielding the result that Meall Gaineimh is 913.6m high and therefore 0.8m below the benchmark height of 914.4m/3000ft. The data set will now be sent to Ordnance Survey for processing and the official result.
Meall Gaineimh is a fine hill whatever its height, as indeed is Knight’s Peak, Sgurr nan Ceannaichean and Beinn a’Chlaidheimh. Heights, drops, distances and aesthetic appeal can all help determine a hill’s qualification for a list. But the time spent investigating our wonderful uplands and visiting the tops of hills is the main reason why we survey their heights in the first place, and with candidates remaining to investigate and survey for potential Munro Top status our endeavours in the Highlands are ongoing.

Here's a film they made on the day:

Please click {here} to see the original article published on the UKHillwalking website

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