established in August 1943. The section had the responsibility both for issuing formal requirements and specifications to the relevant development and production sections, and for testing prototypes of the devices under field conditions. It ensured that operational requirements were properly assessed, trials conducted, and quality monitored. Over the period from 1 November 1943 to 1 November 1944, the section tested 78 devices. Some of these were weapons such as the Sleeve gun or fuses or adhesion devices to be used in sabotage, others were utility objects such as waterproof containers for stores to be dropped by parachute, or night glasses (lightweight binoculars with plastic lenses). Of the devices tested, 47% were accepted for use with little or no modification, 31% were accepted only after considerable modification and the remaining 22% were rejected. Before SOE's research and development procedures were formalised in 1943, a variety of more or less useful devices were developed. Some of the more imaginative devices invented by SOE included exploding pens with enough explosive power to blast a hole in the bearer's body, or guns concealed in tobacco pipes, though there is no record of any of these being used in action. Station IX developed a miniature folding motorbike (the Welbike) for use by parachutists, though this was noisy and conspicuous, used scarce petrol and was of little use on rough ground. Transport The continent of Europe was largely closed to normal travel. Although it was possible in some cases to cross frontiers from neutral countries such as Spain or Sweden, it was slow and there were problems over violating these countries' neutrality. SOE had to rely largely on its own air or sea transport for movement of people, arms and equipment. Air SOE had mostly to rely on the RAF for its planes. It was engaged in disputes with the RAF from its early days. In January 1941, an intended ambush (Operation Savanna) against the aircrew of a German "pathfinder" air group near Vannes in Brittany was thwarted when Air Vice Marshal Charles Portal, the Chief of the Air Staff, objected on moral grounds to parachuting what he regarded as assassins, although Portal's objections were later overcome and Savanna was mounted, unsuccessfully. From 1942, when Air Marshal Arthur Harris ("Bomber Harris") became the Commander-in-Chief of RAF Bomber Command, he consistently resisted the diversion of the most capable types of bombers to SOE purposes. SOE's first aircraft