Unable to afford university, Mr Kornicki, born in Hrubieszów in 1916, joined the Polish Air Force Academy in Dęblin as a cadet.
He served in Poland, France and Britain during the war, before going on to join the Royal Air Force.
The fighter pilot was one of hundreds of Polish airmen who retreated across Europe when the Nazis invaded the country in 1939.
In 1940, the pilot arrived in Britain, where he joined the 303 Squadron, one of 16 Polish squadrons in the Royal Air Force and the highest scoring during the Battle of Britain.
On July 23 1941, he famously led a group of British bombers over northern France where they shot down four enemy aircraft.
He described the experience in his biography, Kornicki, The Struggle: Biography of a Fighter Pilot.
‘We were over twenty thousand feet with France below us when I heard on the RT [radio transmitter] that enemy aircraft were approaching, and later there were reports of attacks and warning shouts – somebody was fighting somewhere.
‘I thought we were moving about a bit nervously when I remembered the golden rule: never fly straight and level for any length of time – and so I too weaved behind my energetic leader, trying desperately not to collide with anybody and not to lose him.
‘I managed, but I did not see much else except him and my immediate neighbours. Our squadron was not molested and we all came back in one piece. I landed drenched with perspiration, jumped out of my aircraft, lit a cigarette and inhaled deeply.’
At just 26, Kornicki became the youngest squadron commander in the Polish Air Force.
He went on to receive the War Order of Virtuti Militari, Poland’s highest military decoration for courage and heroism.