In Stern's book manuscript he talks about Torpedo Spuds, Unditching Beams and rails then he states that there was a LATER development called the Skew-log Device. Does anyone have photos of this?
Skew-Log Device
A later development of the Unditching Beam was known as the "Skew-Log" unditching Gear. This was similar in principle to the Beam and Torpedo, but was in the nature of a compromise. Instead of one beam, there were two short beams, one for each track each attached by chains so that it could swing past the projections on the roof of the hull, so obviating the use of the long unditching gear rails, a quite short length on each side just sufficient to keep the skew-log clear of the track when not in use being all that was required. Further, Both this and the Torpedo Gear could be operated without first locking the Differential which obviously was necessary with the continuous baulk. On the other hand, short baulks could not be relied on to function so effectually as the continuous beam..( 1919 - Lieutenant-Colonel Sir Albert Gerald Stern KBE CMG)
Never even heard of it before, never mind seen it.
But I think we can deduce what it probably looked like. I suspect a track plate bar to attach it, as with the single beam. But, crucially, 2 chains attaching the beam to the bar. This would keep it roughly at 90 degrees across the track, especially under tension. One of the problems with the torpedo spud was the single chain, which allowed it to swivel parallel to the track and become ineffective. It was also too slim to give any traction. What the vestigial rails looked like is open to conjecture.
I note that the Tank, Mark VIII also lacked full unditching rails - is it reasonable therefore to assume that it was designed to use the 'skew-log' as well?
Are there any photos showing one of them 'fully stowed' (presumably post-war in the US would be the most likely)?