This is the bonus cache for the pair of Ad-Labs below, which start at Princes Risborough, and Chinnor railway stations repectively. As per the guidelines, this bonus is linked to one Ad-Lab, Ghost Trains- although there is no requirement to complete Heritage Trains first, I recommend it!
Heritage Trains Ghost Trains
Part 1. Before completing Ghost Trains Ad-Lab, solve this puzzle to aquire the means to decode the Ad-Lab journal entry codes.
The Class E2 0-6-0T steam locomotives were built between 1913 and 1916. The first batch of five had small water tanks, which soon bacame apparent was a significant problem with short range, so the next batch of five had extended water tanks (second pictue) but now a serious lack of coal storage became the problem, which meant they were restricted to shunting, and short local duties. So that was it, only 10 built, and none survive, except that the fictional Thomas The Tank Engine was based on a Class E2.
Thomas will kindly provide you with the keys to the cache-
His wheels have a diameter of 44.5634 inches, have 14 spokes, and his right hand side wheel spokes are numbered 0 to 13 in a clockwise direction. Starting off with spoke number 0 pointing downwards to the rail, Thomas puffs forwards out of the engine shed to the points, which are 86 yards 1 foot 2 inches away. Which number spoke is now pointing to the rail? = A. From where he has stopped, he puffs in reverse to the siding, to hitch up some coaches, which is 154 yards 1 foot 4 inches away. Which number spoke is pointing to the rail? = B. From where he has stopped, he puffs forwards into the station which is 207 yards 0 feet 8 inches away. Which number spoke is now pointing to the rail? = C.
(Round off any messy numbers to the obvious whole number)
You should now have 3 numbers. Using the checker and the published coordinates, add A to the Northing minutes (numbers before the decimal point), deduct B from the Northing decimal minutes (numbers after the decimal point), and add C to the Westing minutes (numbers before the decimal point). This is only a checker, there is nothing at these fake coordinates, just a field! But the checker does contain instructions for how to use the keys to unlock the cache location.
For anyone who is really struggling with the puzzle, the solve method is in the gallery, first picture.
Part 2. Complete the Ghost TrainsAd-Lab to reveal codes in the journal entries, then using the keys solved in the above puzzle, and the instructions in the checker, locate the cache. Good luck, and have fun!
There are lots of pictures of past and present in the gallery.
The second checker below is for the GZ coordinates, once the puzzle within the first checker has been solved.
Congratulations to Simply Paul for the FTF!
I have added some significant hints to solving this, it's a deceptively tricky 'simple' puzzle, but when broken down, and a huge amount of the large numbers are discarded, it's very quick and simple maths! If you need more hints, or show to your workings, please ask, this cache is to be found, not struggled with and ignored.