Almost 20:00 now and I can’t see this being a major effort on my behalf, I didn’t sleep last night and it took me over seven hours to get from Arnish to Port Glasgow, so I’m pretty well wrecked. Not only that but the three of us from Raasay ‘missed the boat’ so to speak and never got aboard the MV Hallaig who was, amongst other things doing speed trials down the ‘measured mile’ at Skelmorlie,
Before a new owner would agree to take possession of a vessel constructed in one of the Clyde shipyards, it was necessary for the builder to conduct sea trials, and prove the vessel performed to the specifications laid down in the purchase order. These trials were conducted with the vessel steaming at full power over a 13.666 nautical mile (15.736 statute mile) course between the Cloch and Cumbrae Head lighthouses, in a procedure known as Running the Lights. Tables from the period show that at 14 knots the run takes 58 minutes 34 seconds; at 20 knots, 41 minutes. Having completed one run, the vessel would then turn around as quickly as possible and repeat the run. This reversal was intended to negate the effects of any wind and tidal input to the vessel’s performance. In reality, the time taken to complete each run, stop, and turn the vessel for the second run meant that wind, tide, and weather could all have changed from those current on the first run, thereby negating the averaging effect of the two runs.
To solve this problem, the test distance was reduced, with the steamer pier at Skelmorlie marking one extent, and the Skelmorlie Hydropathic Hotel, south of Skelmorlie Castle, the other. Measuring 6,080 imperial feet, this nautical mile came to be regarded as the most important Measured Miles in Britain. The nautical mile was later redefined within the international system of units, losing approximately 10 feet in its length, defined as 1,852 metres.
The measured mile at Skelmorlie was notified on July 4, 1866, in a Notice to Mariners, No 36. The unlit beacons marking the mile were described as a single pole, 45-feet high, with arms 10-feet long forming a broad ( V and ‘inverted’ V ) angle 15-feet from the base, the whole being painted white. Once the ‘V’ and the inverted ‘V’ were aligned they became an ‘X’, at which point the tester’s stopwatches would be started or stopped dependent on whether the start or finish of the run was being recorded. From the precise time recorded for the run, and the known distance between the beacons, the results were read off from standardised time and distance tables published in almanacs.
Prior to running the measured mile, vessels would be brought into a steady state of motion, maintaining steering and power constant to avoid any influence and distortion of the final speed calculations. Prior to passing the markers, vessels would always run a straight and steady course for up to four miles, allowing course and speed to be stabilised.
At the end of each run the vessel would turn and repeat the run in the opposite direction, using the same engine power and revolutions. This procedure was intended to cancel out any affects arising from wind, weather, and tide, once an average speed was calculated over the two runs. It was customary for at least two return trips to be made over the course, with results being deemed acceptable if they were in agreement. Variations are reported to have been in the order of 0.5%.
The Skelmorlie markers are no longer depicted on OS maps, suggesting that they have fallen into disuse.
That’s from here http://www.secretscotland.org.uk/index.php/Secrets/MeasuredMiles and seems to imply that they are no longer used, hardly surprising in the days of GPS. However, according to the AIS http://www.marinetraffic.com/ais/shipdetails.aspx?mmsi=235099235&header=true Hallaig did clock up an amazing 11.2 knots and she was certainly down that way at the time.
http://www.geograph.org.uk/photo/441590 Thanks to Thomas Nugent for those pictures of the markers which certainly look serviceable.
On the boat
Well that didn’t go as planned so I’ll try and compose myself, it’s now almost 19:00 on Thursday and that’s me just showered and settled down nicely at ‘The Man From Gourock’s ‘ house with it’s fine views over the Clyde. Having driven south yesterday none of the Raasay crew managed to get on board MV Hallaig so we spent the afternoon at Ferguson’s pouring over the plans and had a look at her sister the MV Lochinvar.
Presently at the ‘fitting out’ berth she’s about where our boat was six months ago I guess, though I suppose with the experience gained from building Hallaig she’ll be finished sooner.
With the ship not due in until 19:00 we called it a day and headed to our ‘digs’, mine being a comfortable flat belonging to my mate and my workmats a dive in Gourock http://www.tripadvisor.co.uk/Hotel_Review-g186553-d1103818-Reviews-Port_Harbour_Hotel-Greenock_Inverclyde_Scotland.html called the ‘Port and Harbour’ hotel. Don’t believe the four and five star reviews, the place was a dump, holes in the wall, stains on the carpets, terrible food and only two cereals for breakfast. They had a choice of ‘Cocoa Pops’ or ‘Chocolate Cheerios’ with their cremated bacon.
Myself on the other hand enjoyed a tiger prawn pasta with my mate and his partner,
needless to say, they are now in another hotel and I’m back ‘slumming it’ with my pal
Anyway, prior to him arriving home I had the pleasure of watching our very own Hallaig conducting a few ‘twirls’ just off Gourock.
OK, I know its not a very exciting video, and I’m gutted that I wasn’t actually on there or even had the sense to get the camera out sooner and switch it to video for she was doing some impressive manoeuvres.
And when you consider that the pictures and video were taken at 32x zoom from over a mile away with a camera that costs less than £300 they’re pretty good. Especially when said camera travels everywhere in my grubby pocket, has been left out in the rain, dropped, abused and even covered in hot oil. Yes I can thoroughly recommend the Panasonic DMC-FZ48, the DMC-FZ38 I had before had even been dropped in bog and run over by a quad!!! and it still worked, the only reason I got a new one was because some thieving delinquent toad stole my old one
After a really good sleep and a proper breakfast of muesli, Greek yoghurt and a banana I headed for Ferguson’s to at last join our new ship. I know, I know, that’s a ‘whimps’ meal but I really am sick of fried breakfasts.
Our fine ship was already covered in shipyard workers and sub contractors from the many companies involved in fitting her out but our main area of interest today was centred around the ‘Voith Schneider’ propulsion system. Our ‘teacher’ for the day being an engineer from the company in Germany called Jorge.
Jorge had us up in the wheelhouse explaining the electronic control system and it’s various modes of operation, as the Loch Striven has a much more ‘agricultural’ mechanical method of operation. The newer joystick controls may be more responsive and efficient but I do like simple ‘bomb proof’ mechanical levers
Of course you don’t get these lovely screens to look at with levers and wheels but then the old system still works if you get struck by lightning
There was also much instruction around the drive unit itself, but it’s almost 20:30 now and time for me to start making dinner as my hard working mate will be home shortly.