After excelling at school in both sports and his studies, he went on to read law at Glasgow University and graduated with a degree in Scottish Law and forensics medicine in 1939.
After joining the Territorial Army in 1938, Lt Col Neilson went on to become one of the first Air Observation Post volunteers, whose job it was to accompany Spitfires and other military aircraft on air-to-air missions and watch from the air for potential targets on the ground.
Lt Col Neilson played a vital role in the D-Day landings in 1944. He was one of the first to arrive on the beaches and was tasked with finding a suitable area for aircraft to land.
On the evening of D-Day, army pilot Ian Neilson, was sent on a lonely mission on a James motorbike. First though, he had to wade ashore from the landing ship (LST) and find it, from any of three possible sites in aerial recon photos, in a waterproofed vehicle.
He had to ride across the battlefront and around minefields in order to find a site from which he could feed target corrections back to naval gunners — in the hope of stopping the Germans from bringing up reinforcements fast enough to counter the invasion.
Indeed, his small task force, which had arms and explosives, as well as aircraft spare parts and fuel on board the tank carrier, had to remove obstacles from the landing site once it was identified.
The first two examined were covered with crashed gliders, parachutes and dead animals. Neilson made his choice of site for the AOP at midday
The chosen one turned out to be three fields of a farm at the village of Plumetot, then covered with obstacles such as anti-landing poles erected by the Germans as well wire fences, a concrete water tank and electricity pylons.
He rode back to collect his working party of five men and another officer, and the waterproofed truck, full of demolitions. The landing ground was ready after they blew up fences, electricity pylons and a concrete water trough. The squadron’s first five Auster IV aircraft arrived the next day from the base in England to provide additional support to troops on the ground.
He flew in an Auster IV plane, which was a high-winged monoplane unarmed light aircraft which was used for observation runs to report and guide the Allied forces about where to attack and where to avoid. Flying without parachutes to reduce weight.
Directing fire meant “climbing like mad” to observe a particular shell’s flight from between 500 and 1,000ft. “The art was to get the aircraft pointing in the right direction when the shell came in to land,” Neilson recalled. “I found myself often observing through the roof.” To the gunners’ “ready”, he would use radio to give the order to fire.
The biggest shells, from 15in naval guns, were each several feet long and weighed as much as a modern Smart car — almost a ton. There was a risk of being hit; once, a smaller shell passed close under Neilson’s left wing.
So effective was that shooting, from 15 in naval guns, 5.5in and 4.5 in medium guns, and 25-pounder field guns, that German infantry and Panzer reinforcements were crucially delayed – but none of it could have been done without Neilson’s bravery and resourcefulness in the invasion’s first hours, which won him, as an army aircraft pilot, the Distinguished Flying Cross.
He continued to fly, 55 sorties in June and July in these planes and 30 shoots, right up until the end of the D-Day landings. Something he said was the best feeling ever. Small note, he discovered that ship's fire was more accurate due to the method of using compass headings to direct fire than tank's firing coordinate method of grid type coordinates.
The day after VE day, he got married to a hospital worker, he was the CO of a War Crime’s Investigation Unit in Germany in 1945/46 investigated war crimes at Sachsenhausen concentration camp north of Berlin, and he formed and commanded No 666 Scottish Sqn, Royal Auxiliary Air Force, 1948-1953.
Lt Col Neilson, was a very busy man and joined many societies relating to the armed forces, the Royal Institute of Chartered Surveyors, the Boys Brigade, the Royal Yachting Association and much more. Whilst in Marlborough, he edited the magazine Tower and Town, wrote two books, an autobiography and another about his time at the Air Observation Post, Air OP — Action Remembered
http://www.iwm.org.uk/collections/item/object/80017422 for an audio oral history
I would love to see this in a movie