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Waalhaven and the Island of Ysselmonde

Introduction and a prelude

Waalhaven AFB was one of the large airfields of the western provinces, yet not a large airforce base. It had been a civil airfield up to the point that it was militarised in the late thirties. For an extended period of time during the Phoney War period it continued to be used for commercial flights. Shortly before the May war, it was decided that a squadron of modern heavy fighter planes type Fokker G-1 would be stationed on the field. This had much to do with the ability of the field to bear the heavy plane and less with tactical decisions, but having a fighter squadron available south of Rotterdam did pose the advantage to be able to intercept neutrality infringing intruders in this sector. Besides some interceptions of German airplanes during the Phoney War period, the most tragic interception by the G-1 squadron was done on the 28th of March 1940 of a British Whitley bomber of 77th Squadron. A flight of G-1's signalled the crew of the bomber to land its plane on Waalhaven AFB, but the pilot ignored the signals and flew on. After repeated refusals to follow the G-1's positioned behind the bomber and one gave it a burst with its 8 frontal MG's, immediately setting the Whitley on fire, which crash landed nearby Pernis oil farm. One crew member was killed, the others interned. The latter would be released on 10 May 1940 and make it back to the UK.

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Map of the German invasion (may 1940)

The airfield was situated south of the Rotterdam-Waalhaven harbour, on the southside of the Nieuwe Maas river and on the 'island' that was called Ysselmonde. Ysselmonde was in fact an inland-island as well as Hoekse Waard and the island of Dordrecht, albeit that it was surrounded by rivers rather than a sea-arm (Hollands Diep). It was surrounded by water-ways with to its north the Nieuwe Maas, to its west and south the Oude Maas river and to its east de Noord river. On the island lies the southern part of Rotterdam, which was - compared to today - only a fraction of the south end of the city and only developed to about a quarter of today's city plan. Nowadays the entire sector where the fighting took place in May 1940 is part of the city or the stretched harbour facilities which are so typical for Rotterdam today. Waalhaven AFB itself has turned into an industrial area and besides a remembrance plate there is not a single trace of the 1940 airfield or battle to be found.

The extended capacity of Waalhaven AFB was the hinge around which the entire southern component of the German airlanding plan pivoted. Waalhaven was designated to be the logistical epi-centre of the German airlanding operation, the umbilical of the entire German airlift operation in the southern operation area. The airlanding troops would all have to land on this base, and all heavier material and a part of the ammo likewise. Should Waalhaven not be seized or would it be lost during the critical first two days, the entire operation would get jeopardized. Therefore, and from German perspective, it would be imperative to quickly decided things in this corner in order for the logistic machine to develop. In fact, the Germans anticpated to such an extreme extent on a quick decision in their advantage, that the first transport planes were scheduled to land 45 minutes after the airborne drop. This very aspect of the very narrow lapse of time between the airborne landings and the first transport planes landing on the airfield that was under attack costed the Germans hundreds of casualties when it came to the Ypenburg AFB (at the Hague) landing. We will now see how this would work out at Waalhaven?

The defences

It was already addressed that one squadron (12 off) of the very capable Fokker G-1 [Mercury engines] dual-engine dual-boom fighter-cruisers [3e JaVA or 3rd Fighter Squadron] was stationed on Waalhaven AFB. It had been the intention to station another squadron G-1's [Wasp engines] on the base, but these planes were in transition from (an export) configuration into a Dutch configuration and as such not armed yet [some would be finished during the five days' war]. A number of these G-1 Wasps were lined up outside the base, along both legs of the neighbouring harbour roads.

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Fokker G-1 fighter-cruiser

Adjacent to the military corner of the base lay a large aeroplane construction yard. It was the Koolhoven factory, in use for both military and civil airplane construction. Koolhoven had been active as an airplane designer since the infant years of airplane-aviation. He had been a senior designer at Armstrong Whitworth & Co in the UK during WWI and designed the quite successful FK.8 reconnaissance plane of which about 2,000 had been built for the RAF during the Great War. In 1920 Frits Koolhoven had returned to the Netherlands, like the other protocol son, Anthony Fokker who had worked for the other side and hadn't gone unnoticed either. In 1940, by the time war broke out for the Netherlands, the Koolhoven factory had an order in progress for the delivery of two squadrons (36 off) of single engine FK.58 fighters for the Dutch airforce. These planes - in different stadia of construction - were parked at the factory, like a number of other orders in progress, like FK-52 training and observation planes. In an earlier stage FK-58's had been procured for the French l'Armee de l'Air. These few French FK-58 would see little action apart from some fighter patrol sorties in the south of France during the Battle of France in 1940.

The AAA defences on the perimeter closely around the base were as follows: twelve heavy machineguns (specific AA versions), four modern 2 cm Scotti guns and two batteries (in total seven guns) of 7,5 cm Vickers and Skoda guns. On the northern side of the Nieuwe Maas were a couple of other platoons and batteries, all with MG's or light anti-aircraft guns, with a couple of heavier batteries further away. For the things to come, the ground-to-air defences could be considered modest, particularly bearing in mind that the two heavy batteries were quite unsuitable to fight low flying airplanes, since the fire-directional systems and pyrotech ammo demanded a minimum target-distance of 1,000 m.

The army representation consisted of one full battalion of the Jagers Regiment (1), about 750 men altogether. The battalion had only two weeks ahead of the German invasion relieved a simple guards company as the airfield security defence. The battalion had three infantry companies of about 175 men each and a heavy machinegun company with 12 heavy MG's. It also had two armoured carriers with each a Vickers MG at their disposal. The entire heavy machinegun company and one of the infantry companies had L-shape positions along the N and E flank of the field itself, with direction towards the landing strip. A second company was positioned along the road to Rotterdam in order to counter possible subversive raids by Fifth Columnists (!). The third company had been positioned on the narrow piece of land that lay between the northern boundary of the field and the harbour. A spicy detail was that, in order to prevent unwelcome visitors from monitoring the military activities on the airfield itself, a huge two meter high wooden fence had been raised along the entire eastern and most of the northern side of the base. This did prevent insight from the city side but it also caused the two companies outside the field to be blindfolded for anything occuring on the field while at the same time those positioned on the field could not see what was happening beyond the fence either. In other words, an enemy landing outside the field - east or northeast of the fence - could not be seen by three of the companies but the one along the road towards Rotterdam! A few days before the German invasion a high staff officer of the airforce command inspected the field defences and subsequently raged against both the base and infantry commander about so much sillyness, but obviously too little too late.

(1) The Dutch had two 'named' regiments, with long traditions. The first was the Regiment Jagers (Riflemen) and the other Grenadiers Regiment (which is the same in English, Grenadeers). Both regiments had contained first class quality soldiers in past era, but in May 1940 nothing of that tradition had been preserved with exception of mildly better and more professional officers amongst the ranks. The Germans were under the false impression though that these Riflemen still were first class soldiers as opposed to the balance of the Dutch army, which they regarded second class troops - at the most.

Two Vickers-Lloyd lightly armoured general purpose carriers or tankettes [brencarrier like vehicles, both armed with a Vickers heavy machinegun] and a number of casemates [of which only one of a reinforced concrete structure] completed the defences. The carriers had been contained near the entrance of the airbase. Amazingly the infantry CP had been selected in a building that belonged to the base constructions as if an enemy would not primarily strafe or bomb such targets before anything else. It seemed as if nothing had been carefully thought through ...

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Destroyed airfield facilities at Waalhaven (may 1940)

The standing orders for the AFB (which were to be stand-by at 0315 hrs) were the reason for a high degree of readiness of the air- and ground-defences before the German bombers would struck home. The command structure was odd though. The airforce and army units were under command of a Major of the airforce during peacetime, but if a German landing would occure the army battalion commander [also a Major] would get full authority over the defences. Obviously this hadn't help cross unit command or the appreciation of defence requirements. When this was addressed by the inspection that occurred three days prior to the German surprise attack, it was too late to remedy. It would benefit the Germans largely.

The opponents

At around 0400 hrs the AFB was scheduled to be attacked by a full squadron of Heinkel He-111 bombers spearheaded by the staff flight of three He-111 with Oberst Fiebig (Colonel) - commander of KG.4 - who himself was a member on board. The He-111's had been instructed only to use 50 kg bombs in order to limit destruction and to pin-point their raid on the AFB defences and facilities in low altitude passes. Targetting the field itself was ouf of bounce. That made a lot of sense, since the Germans would soon need the field themselves.

An hour after the initial air raids had started the four Coys and 650 men strong 3rd Battalion (9th u/i 12th Coy) of Fallschirmjäger Regiment 1 would be dropped around the field in an arc shaped pattern. Only one platoon of the 11th Company [11./FJR.1] would be dropped elsewhere, at the Rotterdam football stadium of Feyenoord. This platoon had been under the assignment to rush to the Rotterdam bridges to reinforce the landing party that would be flown in at that location at 0445 hrs by a dozen sea-planes.

After the 3rd Battalion had landed it would get less than 45 minutes to clear the airfield and the direct surroundings of Dutch defences. At 0530 hrs the first wave of the air-lift was scheduled to touch down, containing 9./IR.16 and some pioneers. By then two platoons of III./IR.16 would already have landed near the Rotterdam bridges by sea-planes. These two platoons and company troop formed the entire 11th Company of IR.16 and had been reinforced by two heavy machineguns squads of the 12th Company and four pioneers for sappeur duties at the Rotterdam bridges. The were about 100 men strong, which was a very modest strength to raid four bridges and form a defensive perimeter, although initially some support could be given by air-gunners on board of the sea-planes. The balance of the battalion - reinforced with two platoons of pioneers and as a whole commanded by the battalion commander Oberstleutnant (Lt.-Col.) Dietrich von Choltitz(2) - had the assignment to reinforce the bridgehead around the four Rotterdam bridges over the Nieuwe Maas river. They would get support of some infantry guns and AT guns that would land during the morning. Only one AT gun - from the airborne division - had been assigned to land with the first wave.

(2)Dietrich Hugo Hermann von Choltitz (1894-1966) would eventually become a full general in the German army and grow to be one of the most well known German general officers as a consequence of his remarkable decision to capitulate the city of Paris - which he commanded in the summer of 1944 - without destroying the cultural riches of this classic capital, as such denying the instruction by Hitler himself to leave Paris in rubbles. Perhaps Choltitz had learnt from the devastation that he would witness when Rotterdam was 'blitzed' into an inferno on May 14th 1940 and the massive destruction he must have witnessed in Russia. It seems though as if diplomacy by some people surrounding Choltitz helped to have him surrender Paris without devastation.

After this first wave consecutive waves would lift in the rest of IR.16, about half the 2nd Battalion of the Fallschirmjäger Regiment 2, one third of the divisional troops and staff including two companies of AT guns, a battery of six light AA guns, three batteries of 75 mm mountain howitzers, signal squads, transport squads and about two battalions of IR.72 [of 46.ID] reserve troops. Those consecutive waves were scheduled to land until the afternoon of the second day of the operation. The Luftwaffe taskforce Putzier of LF2 would constantly provide cover by patrolling fighter squadrons.

The battle in the sky

At 0355 more than a dozen He-111 bombers appeared from the west. The bombers had flown in making a huge de-tour overseas via the Waddenzee, north of Holland, shifting course southwestwards at Den Helder, flying along the entire Dutch coastline and then finally shifting direction inland into the direction of Rotterdam. The first three He-111's - being the Geschwader flight - dropped their bombes on the airbase buildings and Koolhoven factory. The follow up flights targeted the AA and airfield infantry positions.

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Waalhaven approach

The Fokker G-1 fighters had pre-warmed their engines as ordered. One G-1 was not serviceable, causing only eleven to be operationally ready. These had been spread all over the airfield for them not to be easy targets, but with the down side that air crews that had their fighters on the south and west side of the field needed cars to get to their planes and get airborne. This lapse of time between the first German appearance and the arrival of the last crew at its plane caused eventually three G-1's to be destroyed or crippled by German doing before they could scramble.

It all meant that only eight G-1's scrambled when the first German bombers had started unloading their bombs over the targets. The first Heinkels - also the one with the Geschwader commander on board - were shot down shortly after by the first flight of G-1's that had taken off. But soon shear endless waves of bombers and fighters appeared over the airfield and punished the area for at least one full hour in more or less consecutive waves.

The G-1's were largely outnumbered but still managed to shoot down at least 2 transport planes, 8 bombers and 3 fighters. All these were confirmed kills with another three probables. Only one of the Dutch planes was actually shot down, another one forced to land after battle damage in the province of Brabant. The first one crashed into the Nieuwe Maas, killing the the pilot who had taken off without air-gunner (which had been killed on the way to the plane). Notwithstanding the fact that other G-1's managed to survive the odd balance in the sky, they would almost all share an ill fate. Five G-1's were lost due to emergency landings caused by empty fuel tanks and failing airfields to land. Since all airfields in the west had been seized by the Germans [Waalhaven, Ypenburg, Valkenburg and Ockenburg], the planes couldn't land anywhere with their empty fuel tanks. Only one G-1 landed safely on a Dutch held airfield [de Kooy at Den Helder, in the far north]. Three planes landed on the beach in Zeeland, where they were later shot up by German planes. Two landed on Waalhaven again and fell in German hands. Another G-1 got engaged in a dog-fight over the Hollands Diep after having shot down at least two German planes before. It was forced to make a controlled emergency landing in a crob field in Brabant after it had an engine badly shot up. It was a write off. In the end out of eight G-1's, only one sustained the first war mission, all others had been written off. A terrible result for the small airforce that the Netherlands had.

The Dutch AAA and light air-defences pounded the sky, anxious not to hit their own. The staggering number of German planes overhead presented plenty of targets, also to the light guns and MG's. The batteries around Waalhaven and along the Maas shore in Rotterdam threw masses of led into the sky and scored many hits on the low flying enemy planes of which many wouldn't make it back. Nevertheless the Luftwaffe seemed not to care less. Their brave pilots kept on stinging down to recognized targets and gradually more and more AA positions were put out of action, although mainly by ground activity by the airbornes.

In the meantime the bombers had created havoc and quite some panic amongst the defenders. Loads of 50 kg bombs had been dropped on the trenches and machinegun posts around the field. Particularly the infantry reserve - comprising half a company of men - was hit hard by the bombs, for they had held a stand-by position near the hangars on the field. The buildings on the airfields - including the Koolhoven factory - were set ablaze, much helped by a large ammo cache that had been 'smartly' allocated in one of the hangars. Many defenders in the direct vicinity of the blazing buildings ran for their lives, quite a number had been killed at the northend of the base. The majority of the defenders on the field, that had been able to dug down in their trenches, had survived the ordeal and stayed to oppose the next challenge ahead ...

The airborne landing

Shortly before 05.00 the sky was filled with about 50 or so Ju-52 transporters that approached from the southeast. Flying on an altitude of about 150 m - in flights of three - they dropped their airbornes over the fields east and northeast of the AFB as well as west of the base. About 600 men came to the ground in one rolling wave that took about ten minutes to be completed. Another 40 men or so were dropped near the Feyenoord stadium, as planned. They were intended to reïnforce the small German contingent that at the same time landed directly next to the Rotterdam bridges.

The dense air-to-ground fire caused the German pilots to get quite unsteady on the sticks though. Most airbornes were upset to learn that they had been dropped far away from the targeted airbase and not in the planned arc shaped pattern but in a number of stray concentrations, mostly quite far off of their intended drop zones. The initial plan had foreseen that three companies would land on three different angles of the field sothat an imminent encirclement en lock-up of the defences was a logical follow-up. Since this had seriously gone wrong the airbornes had to improvise and overcome this first sat-back. In that they were much assisted by the fact that the majority that did land close to the target landed in a dead angle east of the defence and caused by the fences mentioned earlier. The airbornes quickly reorganised and started to move towards the field with emphasis on the southeast- en northeast leg of the defences. Some squads didn't even bother to get their weapons-containers but engaged with their pistols and hand-grenades only.

The dense air-to-ground fire caused the German pilots to get quite unsteady on the sticks though. Most airbornes were upset to learn that they had been dropped far away from the targeted airbase and not in the planned arc shaped pattern but in a number of stray concentrations, mostly quite far off of their intended drop zones. The initial plan had foreseen that three companies would land on three different angles of the field sothat an imminent encirclement en lock-up of the defences was a logical follow-up. Since this had seriously gone wrong the airbornes had to improvise and overcome this first sat-back. In that they were much assisted by the fact that the majority that did land close to the target landed in a dead angle east of the defence and caused by the fences mentioned earlier. The airbornes quickly reorganised and started to move towards the field with emphasis on the southeast- en northeast leg of the defences. Some squads didn't even bother to get their weapons-containers but engaged with their pistols and hand-grenades only.

The Dutch soldiers had been taken by surprise by the massive airborne landing. They had been prepared for massive 'traditional' airlandings, hence their focus on the airfield itself, but were now confronted with a full scale airborne assault to the rear of the prepared positions. It meant that the airfield companies had the enemy in their blind rear. Nevertheless the few troops that (notwithstanding the preluding bombardment of their positions) had remained around the area of the NE airfield entrance put up quite a fight against the airbornes. At the same time a considerable part of the Dutch company that had its positions northeast of the field along the road to Rotterdam, made a run for it in stead of raiding the airbornes in their right flank. The poorly operating Coy-Co couldn't control them so that this Company didn't contribute to the defence, save one or two exceptions.

Many of the infantry positions and machinegun posts on the east side of the airfield had to be taken by close quarter combat though. Some furious defenders managed to put quite some of the very boldly and agressively operating airbornes out of action. A considerable number of defenders got killed as well by the aggressive German assaults on their positions and for quite some time the entire southeast side of the airfield was one raging inferno of individual squads battling. It was particularly during this stage that heroism on both sides was shown.

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German airbornes that have landed at Waalhaven (may 1940)

Gradually the airbornes were able to force one position after the other into surrender, assisted by the already landed men of 9./IR16. One by one the entrenchments were surrounded and grenades were thrown into the interior. Sometimes many grenades [the German handgrenades were especially designed to produce a huge blast - they hardly contained shrapnel except of the thin container itself] were needed to force the occupations out. Also the AA platoons continued to shoot at German planes and airbornes until their ammunitions stocks were depleted. Only then they surrendered. The last bit of resistance was ceased by the base-commander who, forced by the German battalion commander Hauptmann (Captain) Schulz, instructed his men to lie down their arms, during which the Major himself was held at gun point by a few airbornes. The last positions on the airfeld itself reluctantly surrendered at that point.

When inside the fence the fate of the defenders had been sealed, the battle continued outside the airbase, particularly on the north end. The airbornes now aimed all there attention and efforts on the remains of the company that was positioned between the fence and the harbour on the north end of the base. Besides the squads that already ran off during the initial stages of the battle, another part of the company was quickly overrun when German airbornes smashed through the fence and surprised some groups in their undefended flank. Other groups were able to withstand the airbornes a bit longer, but the company defended itself not like the two companies on the field had done. The main body of the Coy, including its weak CO, surrendered quite quickly.

An even worse performance was seen from the already mentioned company that had been positioned along the road to Rotterdam. Its commander showed no leadership whatsoever, never noticed that two of his three platoons fled into Rotterdam and when he finally realised how to counter the German presence on the nearby airfield, he could only witness the harrowing emptyness of the positions where once his company had been. The disappearance of this company meant that the Germans had an open route into Rotterdam.

The battalion commander - a career officer - disgraced himself too, like he had done in preparation, as had been etablished by the inspecting staff just days before. The Major had been soly responsible for lacking communication lines between the companies and his HQ. He had considered telephone lines unnecessary since the distances between the companies were only limited! Moreover, when during the past weeks his battalion had been stationed at Waalhaven, he had been more concerned with the barracks of the men and the wellness of his horse than the state of defence trenches and casemates. When the airbornes landed the Major soon considered a prolonged defence pointless and decided to take whatever troops he could find with him to the southern edge of Rotterdam in order to build a new improvised defence there. He took his staff - of which some officers strongly protested - with him and managed to reach Rotterdam. In the end about 100 men from the battalion would join him, most of them of the already mentioned company that had fled the northeastern defences.

At around 06.30 hrs the airfield was firmly in German hands. The next challenge was to silence the AAA batteries that were nearby and still pouring out their lethal grenades on to the numerous German airplanes overhead. One battery was positioned at at distance of about 1,5 km, on a quay in the harbour. The other was about 4 clicks away to the east.

The battle continues

Meanwhile the planes of the transport wing (KGzbV2) kept on flying in and contineously offloaded the airlifted troops and heavy material. They were by then much less challenged by AAA, although one of the two heavy AAA batteries was still operating as well as some light AA at the Rotterdam area in the north. Notwitstanding the challenges - which would particularly become substantial when a Dutch 10,5 cm howitser battalion would start shelling the airfield perimeter - more than a thousand men and considerable supplies and material were flown in during the first day. This airlifting operation would continue until the 12th.

The AAA batteries were felt as a great nuisance by the Luftwaffe pilots and the airbornes were ordered to take care of this challenge immediately. The closest battery was situated on one of the harbour quays. It was equipped with four modern and very capable 7,5 cm Skoda guns. The entrance of the quay was defended by the redundant battery crews [every battery had two full crews in order to be able to operate 24/7], with only two light machineguns and a number of carabines at their disposal. For some time they managed to withstand the German assault, but then treacherous German behaviour settled the matter.

As seen before the base commander had been captured shortly after the first airbornes landed. After the German battalion commander Hauptmann Karl-Lothar Schulz (3) had previously abused this officer by forcing him - under gun point - to have the last resistance surrender on the airfield, this 'brave' German officer had another trick up his sleeve. The Dutch Major was forced by him to wave a white flag, seducing the defenders to give up their resistance. The Dutch soldiers - who recognized the Major - ceased firing. The battery commander reluctantly decided to surrender. Just when the Dutch battery-crew stood up from its covered positions, a German Bf-109 - which had been previously instructed to strafe the battery in assistance of the assaulting party - dove down on the battery and hit a number of exposed crew-members including the battery commander. Immense confusion amongst the Dutch caused several men to decide to break out, and two dozen managed to work their way through the airborne lines and reach safety by crossing the Nieuwe Maas some time later. The remaining men were taken prisoner.

(3) The well-known German author Franz Kurowski, notorious for his poor historical fact-finding, wrote an epic book on Karl Lothar Schulz, who would be awarded the Knightscross for his actions during the May-war in the Netherlands. His regiment commander, Oberst Bräuer, was much opposed to his behaviour and had him even reported to Generalleutnant Kurt Student after several Dutch officers had filed formal complaints about Schulz his gross infringements of the international code, which he would continue to make all three days that he was active. Yet higher up it was decided that Schulz qualified for the Knightscross after all. Kurowski deliberately turned affairs around, stating (amongst other things) that the Dutch Major volunteered to convince both the airfield defence and the AAA batteries to surrender, which all other witnesses of the affair could easily file as genuinly untrue. The even more treacherous event of louring a Dutch unit into surrender by abusing POW's (of which a number were killed or wounded) would occure on the 11th of May near Dordrecht and was the most important issue put against Schulz by Dutch officers. It was that particular affaire that also upset Oberst Bräuer, particularly after Schulz adjutant had confirmed the issue. That particular event - it surprises not - was gallantly skipped in Kurowski's epos. It is however fair to add that Schulz - who would make Brigadier in 1945 - his behaviour, unworthy of an officer, was unique amongst the airborne officers in those days. Most airbornes-officers would show respect and chivalry to their opponents, which was much supported by their regiment (Bräuer) and division commander (Student). Remarkably the first would be condemned to death after the war for his contribution to a war-crime in Greece and be executed accordingly.

Then the last standing defence position was about to share a bit of the fate of the rest. Three 7,5 cm AA guns about 3 km to the east of the airfield [at Smitshoek] were still operating, albeit that the fire-directional control had suffered a short-circuit crash, rendering the pyrotech ammo and guns quite useless. When at 0345 hrs the battery was ordered to full alert, the power-supply failed. The power supply was essential for the fire control unit, which in itself was vital for the semi-automatic ranging device of the guns as well as the settings of the pyrotech ammo. As a consequence the gun crews were obligated to shoot individually and without the assistance of the automatic guidance system. This was quite useless, causing the commander to order to cease fire and spare ammo until a repair of the fire-controls would be done.

Meanwhile, well after the seizure of the airforce base, an airborne patrol had appeared close to the battery, after which the battery commander had his men form a defensive screen around the battery position. Their position was a strategic crossing of dike-roads in the hamlet called Smitshoek, north of Barendrecht. A number of patrols were sent out and one of those engaged a German patrol. The airbornes did not give way though and at some point, when more airbornes had moved to the scene, the battery position came under fire too. During this exchange of fire the battery commander got wounded. He was quickly taken to a hospital in Rotterdam. Suddenly the gun fight ended and the Germans disappeared in the direction of Waalhaven.

Some time after the skirmish had ended a G-1 crew - carrying the fast-firing Browning rear machinegun of their plane with them - arrived. It were a Sergeant-Major (pilot) and his rear-gunner. They had made an emergency landing in Brabant after a dogfight with some German fighters, as described before. They had managed to cross the Hollands Diep at Willemsdorp, chartered a car and had found their way back to Waalhaven. When they reached Smitshoek, coming from the large bridge at Barendrecht, they were stopped at the battery position by a guard post. There they were informed about the fact that the base was probably in German hands by then. They decided to stay and the airforce Sergeant-Major took command of the road block that the battery crew had put up at the main junction at Smitshoek. The Browning machinegun from the G-1 [1,200 rds/min firing rate] was installed on top of the barricades.

At around 11.00 hrs a car approached from the direction of the airfield. It contained airbornes, but there was an unidentified military person standing on the side bar of the car. Again the Germans had the guts to abuse the caught base commander. This time he had been posted on the side skirt of the car, waving a white flag - notwithstanding the fact that the Major had some time before physically collapsed from the intense stress of the events! Four airbornes sat in the car, including the Hauptmann commander of the airborne battalion [Hauptmann Karl-Lothar Schulz]. The car was stopped by a signal from the airforce Sergeant-Major. The Major jumped of the side skirt and shouted "don't shoot - they want to negotiate". The SM ordered him to approach. He replied that they would not surrender. The SM ordered his men to open fire on the airbornes, who immediately returned fire. Two Germans were shot, but the Dutch Major too was hit. While the remaining two airbornes drove off with the car, chased after by Dutch bullets, the Dutch recovered the badly wounded Major and carried him into a nearby barn. Minutes later the Major succumbed to his wounds. Again this particular airborne commander, Karl Lothar Schulz, had shown a very dark side of battlefield behaviour and he would do it yet again the following day.

Upon the previous failure to outbluff the defenders, the Germans sent in no less than two companies of airlanding troops of IR.16. The battery XO, commanding the battery since the commander had left the scene for hospital treatment, had however realised that the rifle ammo stock was almost depleted and the Germans would somehow come back. He had ordered his men to destroy the three AAA guns - for which no traction was left available - and retreat towards their own troops in the Hoekse Waard, south of the Oude Maas. Just in time, for the Germans were only a few minutes too late to intercept these men.

Remarkably, no German action was experienced at the large oil-facilities at Pernis, which lie at the NW extreme of the Island. The extended vessel-yard was defended by a company of infantery and four AA machineguns. Mortars, AT guns and infantry guns were not available. The company sat still and awaited things to come. A British demo-party did arrive later that day of which a scouting party visited the Pernis site. The British party - members of the so called XD Operations outfit that were under (British) orders to destroy the oil facilities - were very concerned that the large oil-supply would fall into German hands unharmed and were there to assist when demolition would be opportune. The Dutch company commander was not particularly charmed by the arrival of the British 'assistence'. They were under the perception that the British had already given up on Holland. Rather than sending assisting battle troops the new ally provided demo parties that, moreover, seemed to disrespect the local sovereignty, let alone local Dutch military command. A bad sign, so these men thought, and they were probably right.

Quite remarkable are the XD Operation accounts that declare the reluctant, sometimes even hostile Dutch receipt of these British soldiers. Apparently they were unaware that they arrived in a country that just had been invaded, that expected constructive allied support rather than a bunch of sappers that came destroying even more and showed quite little respect for the local authorities, whereas they showed little to none vigilance or willingness to fight. It was generally experienced as very disappointing. When months later also Dutch ports were raided by the RAF, causing mostly damage and death amongst Dutch civilians, people started to wonder who was the enemy and who was their friend. Fortunately these anti-British sentiments were short lived, but they had been ignited by a very poor show by British forces that for a brief moment did show their faces on Dutch soil [larger formations in Flushing, Hook of Holland and Ymuiden; small parties at Pernis, Rotterdam and Amsterdam] in those infamous May-Days of 1940.

One last event is worth mentioning. Somewhere during the day - an exact timing fails - a car arrived at Pernis that drove straight into a concealed Dutch check-point. On board a German officer and NCO. These two men demanded the surrender of the Dutch force, but they were captured and shuttled over the water to Rotterdam. The officer on board was in fact the 'field intel officer' of Student's staff, who was apparently looking for an easily earnt Iron Cross, but would in fact get a slap on the fingers after. It was Oberleutnant Hans Lampertsdörfer with an NCO that he had chartered to drive a seized Dutch car. This eloquent German officer, that would afterwards write a ridiculous article in "The Adler" about his actions, had simply driven off into the general direction of Rhoon - to the SW of Waalhaven - and from thereon all the way to the large petrol harbour of Pernis in the far NW of the island. Not a single airborne had been in this sector yet, so it was quite unchartered terrain to them. Apparently Lampertsdörfer overestimated the weight of him being an officer and estimated that he would be treated as a negotiator, notwithstanding that he did not come unarmed or under a white flag. He protested when he was arrested at gun point and quite firmly taken away. The Dutch mocked his abuse and arrogant behaviour. This German officer was lucky to be imprisoned in Rotterdam itself, which caused him 'to miss the boat' to Canada and be released after the May War. He would of course complain about his treatment, but that didn't work out in anything considerable. A year later, meanwhile being promoted to Hauptmann, Lampertsdörfer vanished in Greece, flying on board a Bf-110 strategic recce plane of the division.

Air interdictions

The German seizure of Waalhaven AFB was soon big news in several staff rooms. Besides the obvious cheers on the German side, the shock was felt in the Dutch headquarters, which soon found its way across the Channel when British staff officers were informed by a cable message. The early German seizure of this airfield was also regarded very undesireable by the RAF, which immediately gave priority to a number of air interdiction raids by Blenheim and a Swordfish squadrons, later followed by a serious rolling night bombardment that would involve no less than seven RAF Bomber Command squadrons. Serious efforts by the British to interdict in this theatre. Waalhaven and Ypenburg - the latter already retaken by the Dutch by the time the British dropped bombs on the airfield - would experience the dedication of the RAF on the continent, which would be a very costly operation.

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Bristol Blenheim Mk.IV (may 1940)

The first two RAF interdictions were quite poor efforts. That is to say, the 'lightness' of the means that were sent in were poor, not the efforts in itself. The British Blenheim airplane was used as a recce, 'medium' [the British called this medium, the Dutch would call it light] bomber and fighter-cruiser. It was perhaps capable of the first, but the second and third were way beyond the capacity of this vulnerable airplane. It was however the work-horse of all the RAF could field in these days when it came to ground support, besides the even less capable Fairey Battles. Yet brave men were relentlessly sent into hostile France, Belgium and Holland during the first day of the German invasion, which caused about half the fleet to be lost over the continent, including most of the brave flying crews. It wouldn't be much different in the Netherlands, where RAF losses would mount too.

It was 600 Squadron bearing the brunt. It was equipped with the Blenheim 1F, a fighter-cruiser in the catalogue range of the Messerschmitt Bf-110 and Fokker G-1, but way less capable than the latter two. The squadron would fly a strafing mission with two flights, led by it's S/L. It was shortly after noon that the British came in low from the Northsea, totally missing a German squadron of Bf-110's that flew a high altitude patrolling course. Roughly over Pernis harbour the German fighters dove down on their pray with blazing guns smashing four Blenheims to pieces. Two others were damaged and took off in a southern direction but managed to strafe a row of Ju-52's on the airfield. Shortly after this one of these Blenheims was also shot down, causing only the single one flown by F/O Hayes to escape and reach his base again. Five Blenheims had crashed, seven crew members amongst whom S/L Wells were killed, one would later become a POW when the hospital he was treated in came in German hands, three men were repatriated on board the destroyer HMS Hereward, from Hook of Holland. A dramatic result.

A second interdiction sweep would see more fortune. It was 15 Squadron flying the Blenheim IV light bomber that had to raid Waalhaven with 250 pound (112 kg) bombs of which it could carry four internally and a few lighter bombs (probably 8 x 40 pds) on the wings. These slightly bigger Blenheim IV types were still extremely vulnerable, but could deliver at least some punch with their payload. These underpowered planes suffered however from very low cruising speed and poor self defence, whereas the passive defence was poor too. Yet eight Blenheims took off and set course for Waalhaven where they arrived in a lull between rotations of German air patrols (4). This fortune caused the Blenheims to be able to penetrate the German dominated sky over Rotterdam and all eigth deliver their full load (an then some - MG fire) on the airfield, that was packed with German transporters, material and personnel. This interdiction caused them Germans not only a mild shock, but caused quite a material and personnel loss too.

(4) If the often applauded German airfleet of those days shared one remarkable design flaw it certainly was the modest range of its most prominent strike- and fighter-planes, with exception of the Ju-88. The German fleet was largely designed around a ground-support and nearby air-coverage idea, which caused many of their prominent types to have little endurance over the battle field when this moved away from the air-bases. This flaw was most prominent when it came to the only real capable fighter of the Luftwaffe in May 1940, the Messerschmitt Bf-109E. This little interceptor, that was designed for high speed high altitude cruising, was a fuel absorbing fighter of which the makers had offered much to maintain an attractive power-to-weight ratio as well as thin wings. These features didn't agree with a larger fuel storage, causing the fighter to suffer from serious range issues. For example, a fully armed and fuelled Bf-109 coming from the average airbase in the west of Germany burnt 75% of it's fuel in transit to and from the Rotterdam theatre, which gave the average Bf-109 max. 20 minutes of patrolling time and about 10 minutes of combat time in the targeted airspace.

Since the German air capacity had to be divided over a vast territory between their own country and the north of France, fighter squadrons were divided in three or four so called Schwarms (two flights of two fighters) that flew a rotation schedule in a certain airspace or corridor. With the very limited capacity of max. 20 minutes actual patrolling time over the target area in the west of Holland or Belgium, the slightest hick-up in the rotation schedule would cause a lull in the air coverage in a dedicated airspace. That was most likely the reason why RAF 15 Squadron managed to squeeze in this German dominated airspace, deliver its full ordinance without being challenged in the air, and make it out virtually unscaved.

The German losses were a little exaggerated by the enthusiastically debriefing RAF crews. These had counted no less than 16 Ju-52 destroyed. That was not the case. There were 32 Ju-52's on the entire field at the very moment of the RAF raid and it was not the case that half of them had been destroyed. According to German reports, which were reliable, eight Ju-52's were destroyed, a few Luftwaffe men killed. Furthermore German reports reveal that two airborne antitank guns and one airborne 2 cm AA gun were destroyed with a mild loss of personnel. The losses shall have been around 20 men KIA and WIA. The event warned the Germans not to concentrate too much men and material on the AFB and it is almost certain that a raged radio message was sent to the airforce headquarters about the lacking fighter coverage.

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The Fokker D-XXI fighter (may 1940)

The Dutch flew a number of interdiction raids too. Already in the earlier morning a flight of five light bombers Fokker C-X tried to reach the German dominated sky over Rotterdam. They deliberately took the exact German route of the very morning attack, along the coastline, turning inland west of Hook of Holland, lining up with the Waterweg (Waterway) and carpet bombing the airbase with 8 x 50 kg bombs each from an altitude of 2,500 m. The bombs came down on the airfield and must have caused some damage, although it is uncertain to what extent. On their way back two of the unescorted bombers were intercepted by Bf-109's and forced to make an emergency landing. None of these had wounded or killed crew members. Remarkably enough the three escaping C-X's did. Two of them saw the observer annex rear-gunner receive serious injury, only one managed to return totally unscaved. All three returned C-X's had some damage but would return to the battle field.

The second Dutch effort was executed by the only squadron of genuine and modern bombers that the Dutch possessed, the Bomva, that operated Fokker T-V medium bombers. These were capable of delivering 1,000 kg of bombs and had a self defence capacity of a 2 cm gun and a number of manned MG's. There was one catch, most T-V's were still fitted with a trial bomb rack only capable of max. 600 kg of bombs rather than the 1,000 kg for which the bomb bay had been designed. Three of these T-V's were included in this mission and escorted by two flights of Fokker D-XXI single engine fighters. Shortly after noon, possibly around the same time that the RAF Blenheims were trying to reach this airspace, the Dutch formation of nine managed to reach Rotterdam, but at that point the fighters were forced to engage a dozen or so Bf-109's that tried to intercept the Dutch. The fighter pilots, amongst whom Lt. Jan Plesman who would later join RAF 322 'Dutch' squadron and - as a F/L - go MIA during a search and destroy patrol over French territory on 1 September 1944, gave all they had. In the meantime the three T-V bombers managed to make it to the aifield and dropped their bombs over the NE corner of the airfield.

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The Fokker T-V strike plane (may 1940)

Two of the T-V's were intercepted shortly after their bombing run was concluded. One of the planes was jumped on by no less than six Bf-109's, that shot it down with no chance for the crew to bail out. The other intecepted bomber shared this fate, with one man barely able to jump out and live through the ordeal. Seven men perished. Also one of the fighters had been downed with a dead pilot on the stick, while a second fighter returned home with a strained plane that was written off too. A costly mission for the tiny airforce. German losses were reported by the Dutch but not confirmed. Losses on the ground from the bombs are not traceable in the German accounts. There must have been some, but it serves no purpose to guess.

There had been a weak third attempt by a number of obsolete Fokker T-V light strike planes with 25 kg bombs, coming from the province Zeeland, but these airplanes had been intercepted before they could reach the target area and two C-V's had been downed, killing most of the crew.

Last but not least a rolling RAF bombardment would target Waalhaven AFB overnight. It would be followed - or at least that was the plan - by a Dutch ground counter-strike by the Light Division that - by nightfall - had reached the eastern outer border of the Island of Ysselmonde in force. It would cross the Noord with two small regiments and march on to Waalhaven and retake it. This all would be preluded by a RAF bombardment flown by seven squadrons, each comrpising one or two three-bomber flights, totalling 36 Wellington bombers in total. It involved 9, 37, 38, 75 NZ, 99, 115 and 149 Squadron of No.3 Group of Bomber Command. Each of these Wellingtons was capable of delivering 2,000 kg of internal payload. It was a bomber in the same range and class as the Fokker T-V, with the same perks and flaws, although slightly bigger max. pay load. Since the raid would be executed by moonlight only the chances of survival were good. The raid was planned with a load of 18 bombs of 200 lbs, which amounted to 1,600 kg of bombs per Wimpy getting the entire total to 58 tonnes, which was quite significant for those days, particularly bearing in mind that a few days later the German KG.54 would drop 97 tonnes on Rotterdam's city heart and totally destroying it. Most challenging would be to find the target in pitch black circumstances, reason why flares were used to light up the target area before bombs were dropped.

The first Wellingtons appearing overhead were those of 9 Squadron. The task of the point flight had been to fly low and only bomb on certain target identification, in order not to mislead the follow up flights. They flew in on 1,500 feet height, made a flare pass first and subsequently bombed the airfield and surroundings. The next flight flew in on 6,000 feet and dropped its load on target too. Probably some incendiary device was used to lighten up and mark the target for follow up flights, because a fierce fire broke out immediately after this first wave. Three subsequent attacks by 37, 38 and 75 NZ evolved flawlessly, and so did the next three sections of six by the other three squadrons. If all really went as flawless as RAF crew reported back is questionable. At least on flight of Wimpy's did not find the target but in stead bombed a Dutch held section of Rotterdam, killing a couple soldiers and possible some civilians too. In the morning, the airbase was still a light inferno and German troops had been shocked by the events that they had went through. Unfortunately the Dutch had failed to meet the deadline and couldn't follow up on the RAF raid, causing it to be a stand alone incident. The airfield had suffered from the detonations and possibly some material and personnel losses had to be taken by the Germans, but they had largely evacuated the field anyhow, while the guarding personnel was mainly found in manholes outside the actual base. Quick repairs of some strips caused the Germans to be able to use the AFB to some extent on the next day, regardless of the air-raids and continuing Dutch shelling of the place.

Kurt Student

After Generalleutnant Student and his staff had landed around 0900 hrs, the General had himself being briefed of the status of the operation after which he had given his first instructions to the units at his disposal. He quickly moved to the south of Rotterdam where he assured himself of the status of the operation by visiting the troops close to the front.

The bridges and ferry-points connecting the Island of Ysselmonde all had to be secured, particularly along the NE, E, SE and S sides. Taskforces, often no more than about a platoon size, were directed to locations like Ridderkerk and Barendrecht; Spijkenisse, in the far west of the Island, was only briefly visited by a German recce troop but it was countered by Dutch patrols on its way. At the bridges of Spijkenisse and Barendrecht Dutch and German troops would be opposing each other with neither side controlling the bridges during the days to come. This was however in line with the German ambition and as such no benefit to the Dutch. At Ridderkerk a river ferry service had to be occupied by the German side, which they managed to do. There was however a little surprise awaiting the Germans in the vicinity of Ridderkerk, to which shall be returned hereafter.

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The German headquarters in Rijsoord (may 1940)

During the day Student and his staff used a command post in a Dutch school in the south of Rotterdam. When it became apparent that the operation in the heart of Rotterdam had run dead on Dutch resistance whilst the reinforcements landing on Waalhaven were way behind on schedule, Student grew worried. When also the Dordrecht bridgehead was reported to be frail and consequently challenged by Dutch formations, Student designed a fall back scenario, which would be much opposed by his chief-of-staff Major Trettner and the other operations section officers. The General decided that if the situation would grow even worse - and the bridgehead at Dordrecht would get into serious danger of collapsing combined with a potential Dutch counter offensive in the heart of Rotterdam - that the Rotterdam bridgehead as well as Waalhaven would have to be evacuated and the entire force would withdraw as far as the small village of Heerjansdam, which lies about 5 km west of Zwijndrecht. The bridgeheads at Dordrecht and Moerdijk were not to be jeopardized, were considered imperative to the success of the operation.

As a first measure of safeguarding the Dordrecht bridgehead, the 3rd Battalion of airbornes would have to be sent to Dordrecht, leaving only a very weak force on the Island of Ysselmonde and hardly none on the Waalhaven airfield. The parts of I./IR.16 and II./IR.16 that had landed were assigned the defence of the east and south of the Island. Other smaller formations were held in reserve. The commander of III./IR.16, Oberstleutnant Von Choltitz, who had most of his battalion assembled and held his HQ on the Noordereiland in the heart of Rotterdam, was instructed to evacuate the city entirely once the Dutch pressure would demand such or if instructions would be given to do so. The Oberstleutnant objected strongly, stating that his forces would hold and that he would prevent Dutch crossings of the river. Student gave him some leverage but only under the current circumstances.

In the early evening it was decided that the division staff would be more centralized near Rijsoord, in order to control things from there and in consideration of the potential withdrawal to the east. Sometime during the evening Student received the upsetting news of a large unknown bridge at Alblasserdam (south of Ridderkerk), only a relative distance from his new HQ. The very existance of that bridge had not been established by the German intelligence and as such it did not exist on the German maps of the country. Funny enough Student "blamed" this on the Dutch, when he stated [in his memoirs] that the bridge had not been on the Dutch maps and by that omission it had been overlooked by his staff. Indeed - only the most recent Dutch maps did indicate the new bridge [that had been delivered in November 1939], but the outdated maps - of which plenty were still in use - showed no sign of a bridge at all. Student quickly sent an additional platoon accompanied by a 3,7 cm AT gun troop to the bridge, shortly after followed by two more platoons and an artillery battery with four pieces of 7,5 cm guns as a response to news that he heard later that evening of the acknowledged arrival of large contingents of motorized Dutch troops on the opposite side. An event that shall be addressed later when indeed on the opposite side of the Noord the first units of the Dutch Light Division were in arrival.

At that point in time, during the night, Student had a serious argument with his staff. The General did however pull rank on them and pursued his plan to reinforce the Dordrecht theatre with the airborne battalion and leave the Noord defences, that were obviously facing strong Dutch field army formations, relatively lightly defended. Student was obviously aware of his gamble, but he thought little of the tactical abilities of his opponent and that, combined with his quite opportunistic character (that would demand high losses at Crete in 1941), settled the matter.

General situational overview

The Germans assessed their achievements as outstandig, but their position as delicatie. In Rotterdam they had managed to prevent the destruction of the bridges and controlled two of the four whereas they could seal off the other two with their weapons. Waalhaven had been quickly overrun, was not jeopardized by Dutch counter measures, but suffered from air raids and arty shelling, which was much of a nuisance obviously. The bridges at Dordrecht and Moerdijk were firmly in German hands, but particularly at Dordrecht the situation could tilt into a dangerous siege by adequate Dutch forces and artillery. That was what Student worried most as we addressed hereabove. The off-sites, which were the west and north west of Ysselmonde as well as the north east, mattered little to Student. He expected no serious opposition, not even by the Dutch formations that had arrived overnight. Student decided to leave only about three companies of troops as a mobile counter force on the Island and move his battalion of airbornes to Dordrecht.

Another thing was a little disturbing. The logistics were falling behind. Partially due to the ongoing Dutch artillery [modern 105 mm howitzers] had been shelling the airfield from the end of the morning until the evening hours. Bombardments by Dutch and British planes had also damaged the runway, of which the worst was yet to come overnight. Besides the structual damage, about a dozen Ju-52's had been destroyed on the airfield, others were too crippled to take off again. In total about thirty planes were sort of tied on the field or been destroyed, which was a serious loss of air capacity. Amongst those losses was one of the two special Ju-52's, which contained a long wave radio to establish contact with the Luftwaffe HQ in Germany. The Ju-52 had been hit by one of the arty shells and was burnt to destruction. This loss caused the Germans to have a much hampered radio traffic with Germany after the morning of the 10th. The space that was left to land the still expected waves of transport planes had decreased dramatically and this jeopardized the entire air-lift operation. Yet Student believed in the recovering capacity of his men and ordered the airfield to be repaired around the clock, constantly providing strips that could facilitate landing or departing planes.

Generally speaking - Student could have been a happy man. All vital bridges in the entire theatre had been seized intact and were successfully defended thusfar, the Island Ysselmonde was sealed off from its surrounding approaches and Waalhaven was firmly in his hands too. Worries rose however over the delicate situation in Rotterdam and Dordrecht, as well as the arrival of mysterious [Student knew nothing of course of the retreat of the Light Division from Brabant] fresh and strong Dutch troops at Alblasserdam. Also - but we will refer to that later - he was very much worried about the fate of his troops that had landed around The Hague. News had already reached him that this operation seemed to develop in a troublesome way.

On the Dutch side there was only reason for great or the greatest concern. GHQ had to coop with direct danger from massive German landings around the Hague. The General Staff was well aware of the imminent threat in the south too, where not only the Peel-Raam line was about to crumble, but where the German airborne operation had caused the huge upset of a lost but capacitated airforce base south of Rotterdam as well as the dangerous German seizure of the Moerdijk bridges. The French CIC had contacted the Dutch CIC and assured the latter that the Moerdijk bridges would be pray for the troops of the French 7th Army that were hurrying north. That left the focus of the Dutch on retaking Waalhaven, or at least put it out of action so that further German reinforcements could be denied. Meanwhile it was realized that Rotterdam needed reinforcements from the Field Army, whilst the Light Division was ordered to cross the Noord overnight and retake Waalhaven before dawn. RAF support had been arranged. Around midnight Waalhaven was to be raided by strategic bombers from the RAF, after which the Light Division could go ahead with its offensive operation on the Island of Ysselmonde. Some sort of confidence grew in the Hague that matters could still be turned into Dutch favour.

Balance of a day

The casualty rates on the Dutch side are specifically known. The defence of Waalhaven AFB and surrounding positions had been a costly enterprise. The Dutch had lost 54 military and 3 civilians KIA and about 600 men had become POW. Four men had been killed elsewhere on IJsselmonde.

The German losses are not specifically known. Their casulaty inventory usually lists men as killed at Rotterdam and doesn't often specify locations. Nevertheless, losses were relatively low again. About 14 airbornes were registered as KIA at Waalhaven. About the same losses were suffered by the air-landing troops (analysis of the German losses provides for a maximum of 20 men air landing troops that may have been killed around Waalhaven). These losses are excluding the Luftwaffe airplane and flying personnel losses, that were repotred as being considerable but of which losses are hard to identify.

The Dutch had lost 11 out of the 12 available [11 operational] G-1 fighters, of which 3 had not been able to scramble in the first place (plus the 12th one, that was in revision). The causes of these losses were already addressed. One pilot had been killed. Six airforce strike planes had been lost on their way to Waalhaven or on the way back.

The Germans lost at least 13 airplanes around Waalhaven which had been shot down during the first few hours. About 30 planes had been seriously damaged or destroyed on the airfield by Dutch infantry- or artillery-fire, Anglo-Dutch air raids and/or crash-landings. A number have been lost after due to Dutch AAA in Rotterdam and follow up air battles, but since these losses can not be isolated from German grand totals, we shall not take a wild guess and leave it at that. The RAF had lost six Blenheims in the morning of the 10th.