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In most cases, the respective pilot participations reflected the postures of the respective militaries. For instance, the Netherlands surrendered only five days into the invasion, under the orders of its commander in chief, Henri Winkelman, who won "paroles" for his men. The Belgians fought 18 days and surrendered only at the behest of King Leopold, who had taken personal control of the military. This decision was against the advice of his government, and he also elected to stay in Belgium, unlike Allied leaders who fled their countries. The French surrendered under Marshal Petain, technically a civilian leader, but actually a war hero from World War I. With the notable exception of Charles deGaulle, the rest of the French military was also "defeatist." AS HorusKol noted, deGaulle's Free French used pilots originally based in North Africa, not France.
On the other hand, the Czechs surrendered only under the direction of the civilian authorities (President Benes) with heavy prodding at Munich from Britain's Neville Chamberlain; the Czech military was more than willing to fight. Poland never really surrendered as a nation, although most individual units did. Part of the army survived by going into exile or maintaining the largest underground, resistance force in Europe. (Much of the latter morphed into the Home Army.) All this meant that many who were willing and able to fight were enabled to do so.
The lack of Danish and Norwegian pilots can be explained by their scarcity, as you said. Otherwise, they were opposite cases. Denmark surrendered after a day, Norway held out as long as it could, and its merchant marine actually went over to England.
Upvote:5
The Dutch army surrendered on May 14 1940. The military was not taking into prisoner of war camps, but released on the promise of good behavior. Most Dutch navy units did not surrender, but continued to fight from England. During the battle of The Netherlands most of the air farce, pardon, that should be 'force', was destroyed on the ground or in combat. Much later in the war the Dutch army was required to report to prisoner of war camps.
It wasn't easy to escape the occupied country. People who did were called Engelandvaarders. One Fokker G1 was later during the war flown to England by Fokker (civilian) personnel who fooled the Germans, saying it was a test flight. This plane was not used in combat. It was tested and after that left to rot away.
So most officers were honor bound to remain where they where. Small detachments or individuals were able to join the evacuation of Dunkirk. The Marechaussee (military police) got 200 man out that way. They served during the entire war as palace guard to queen Wilhelmina who was in exile. How many air force officers escaped I don't know, but it can't have been many.
There were 3 Dutch squadrons during the war in RAF service: 320 321 and 322 squadrons. Do mind that the air contribution of the Dutch wasn't great, but the air farce wasn't much to begin with. The Dutch did contribute much more with their navy and merchant marine ships, especially the latter.
With regard to the Dunkirk evacuation: those Dutch MP's had a bunch of Fallschirm jaeger with them. They were taken prisoner of war during the battle for The Hague. German parachute troops tried to capture the royal family and the seat of government, but failed after fierce fighting. Some were taken prisoner and were transported via Dunkirk to England. Later they were sent to Canadian POW camps.
Upvote:7
In regards to pilots from Metropolitan France not heading to England - many Czech and Polish forces (including pilots) fled over land borders into then-neutral Hungary and Romania in 1939 and were able to make their way to Britain in plenty of time to start being integrated into RAF and Army Command by the Battle of Britain in August 1940. Even then, it was a little while before they trusted to fly into combat.
The Battle of France was lost only a few weeks before the Battle of Britain. The Germans trapped much of the British and French along the coast, and the only land route was Spain, which was neutral but rather unsympathetic to the Allies. In addition, the British-led evacuation (the most famous part of which was centred at Dunkirk) from France prioritised British forces ahead of French. This made it harder for any French servicemen to make it to Britain to join the Free French there by the time of the Battle of Britain.
Further, as TomAU and Sempaiscuba points out, much of the French military stayed with the surrendering government. Whether this was exacerbated by distrust caused by things like the evacuation, or the scuttling of the French fleet is hard to gauge.
Eventually, Metropolitan French pilots did make it to England - but even by 1941, two-thirds of the Free French were in Africa.