The German airlanding in the undefended heart of Rotterdam in the early morning of the 10th had taken the Dutch by full surprise. The first shock was quickly overcome though, and effective counter-measures had been taken by the available troops of the marines, engineers, infantry and intendant units in the Maas-city.
The Germans had tasted initial success and quickly taken possession of the four bridges crossing the Nieuwe Maas in Rotterdam. Fierce Dutch resistance in the south of the city had delayed the arrival of urgently needed reiforcements, which had prevented the Germans from building a firm bridgehead on the north bank of the Maas. Before the reinforcements of the 3rd Battalion of 16.IR [III./IR.16] had arrived, the Dutch had already driven back most of the German troops in the north.
From then on there had been a stand-off situation. The Germans had reinforced their positions on the Noordereiland and the Dutch had carefully sealed the northern city side. The bridges connecting the Noordereiland with the north of the city remained disputed objects that couldn't be claimed by either side.
Dutch reinforcements arrive
The garrison commander Colonel Scharroo had requested for considerable reinforcements at the GHQ. He realised that with the few hundred marines and infantry men that he had avaliable he would be hampered in developing counteroffensive actions.
The reinforcements couldn't come from 1st Corps, which had been tied by the German airlanding around The Hague. Therefore the Field Army was addressed by the GHQ to let go of its reserves and send them (mainly) to Rotterdam. The Field Army command was instructed to send troops equalling the strength of a regiment, including a battery of motorised artillery, to Rotterdam. On the 11th another instruction for an additional two battalions and yet another battery of motorised artillery followed.
1st Corps had sent a battalion of Jagers on the 10th, but that battalion had been recalled by its regiment commander, because it was urgently needed to be involved in the clearing of the dune area between Rotterdam and The Hague.
The first instruction materialised in the assignment of the staff and commander of 11.RI to lead the three reinforement battalions I-11.RI, IV-10.RI and IV-15.RI. The two latter regiments [10.RI and 15.RI] had a fourth battalion [regiments normally only had three] that comprised only three companies of infantry without a heavy MG-company. Along with these battalions came a company of mortars and half a company of AT guns. All these units - together a little less than 2,000 men - arrived overnight in Rotterdam. They had al been taken from the Grebbeline region in the 2nd Corps sector north of the Grebbeberg. Another battalion from 4th Corps followed later [IV-21.RI] that night accompanied by two AT guns. That meant another 600 men or so.
In total the city occupation was reinforced with a mere 2,600 men, 8 AT guns, 6 mortars and two companies of heavy machineguns (as part of the battalion strengths). Their arrival had not be specified to the staff of Colonel Scharroo. He had to wait and see what was been sent to him ...
The motorised artillery never made it to Rotterdam. They were sent to Gouda and would later be returned to the Grebbeline. It was a battery of 10,5 cm howitzers of 12.RA that had been in position north of the Grebbeberg defences.
Group Utrecht - of the eastfront Fortress Holland - sent two battalions from 25.RI and 32.RI to fulfill the additional instruction for reinforcement of the Rotterdam defence. They would arrive on the 12th.
Altogether with the already present Dutch force, the total number of men available in Rotterdam would eventually grow to 10,000 men.
The defences organised
Colonel Scharroo reorganised his defences. He deployed troops along the entire river and to the west, north and east of the city, in order to seal off the entrances against hostile penetration. The latter was done because the Colonel feared actions from landed Germans against the city from these directions. Especially the failed German landings around Ypenburg had caused a German concentration of misdropped airbornes and airlanding troops to the north and northeast of Rotterdam, but even to the west side of the city Germans - that weren't there - were reported.
North and northeast of Rotterdam were around 500-750 Germans, which gradually joint forces at two locations in particular: Berkel-Rodenrijs and Overschie. Both these locations bordered on the northside with Rotterdam. In the west, in particular around the dune area and Hook of Holland, some stray groups of airlanding troops and airbornes had landed too, but they were not nearby the city limits. By sealing off the entrances of the city Colonel Scharroo intended to keep these forces out rather than counteract them.
The Colonel's small staff [six officers; the seventh had been wounded during a reconnaissance mission at the bridges] was very much occupied with the numerous reports about phantom landings and presumed treacherous civilian (Fifth Column) actions. The arrival of new units, the redeployment of the already employed units and the intensive coordination following out of all reports about phoney landings and civilian subversion occupied the staff to such an extend that no organised counter-measures against the German bridgehead would be organised during this second day. The staff was to some level assisted by the navy and marines staff of Rotterdam, but in the end a joint (improvised) staff of about 20 officers and NCO's had to coordinate a force of around 9,000 men [on the 11th], where such would normally been done by a staff of about 50 officers and NCO's. Besides that numeric effect, there was the lacking skill of staff-work among the officers being assigned as such. Almost all were in fact officers from technical branches, such as pioneers, sappeurs, intendants and other support branches. None of them had been schooled in staff work of a field army unit.
At around 0400 hours the Maas-front was again a cacophony of blazing guns, machinegun- and rifle-fire. The Germans at the Noordereiland had overnight put up screens of blankets and cloths in the streets to block the vision of the Dutch side. Along the front some modest successes were booked by the Dutch. Especially the appliance of anti-tank guns and mortars proved very effective against the Germans who had been locked-up in their small bridgehead.
The German spearhead was their occupation [about 50 men] of the Insurance building north of the traffic bridge. This building and its occupation had become isolated from the balance of the German forces by the Dutch progress on the 10th. The courageous German occupation did however refuse to give way, although it was continuously challenged by Dutch fire. The Dutch were very much limited in their options to eliminate this pocket of resistance. Every approach of the building forced units to expose themselves to German fire from the Noordereiland, and it was virtually impossible to use bigger guns against the construction because that would require the used guns to expose themselves to the German defence on the Noordereiland too.
The Dutch airforce assisted the ground forces upon the request of Colonel Scharroo. The first strike was executed around 1030 hrs when two Fokker T-V medium bombers dropped sixteen bombs of 50 kg (1) on the northern traffic bridge. Of the first bomber load, six bombs hit the bridge entrance and the adjacent houses. A large fire on the westside of the Noordereiland was the consequence, which forced the Germans out of two of those buildings too. The bombs of the second plane all landed into the water.
(1) The Fokker T-V was able to transport 1,200 kg of bombs in a configuration of 4 x 300 kg HE bombs [alternatively 4 x 200 kg or 16 x 50 kg]. But in May 1940 the necessary bomb-racks were only available for two planes. The envisaged bomb-racks were still being tested. Meanwhile the balance of bombers had been fitted out with old auxilary racks which were only capable of carrying 4 x 50 kg plus 2 x 100 kg or the basic rack for 8 x 50 kg HE bombs. That was the same payload as the old twin-decker Fokker C-X ...
A repetition of the previous raid was executed at 1330 hrs. Notwithstanding the fact that this time a diving approach had been chosen, all 16 bombs missed the designated targets again.
This time the Luftwaffe responded. Twelve prawling Bf-110's dove down on the Dutch force of three Fokker D-XXI fighters and two T-V bombers. One of the D-XXI's managed to lour six of the Messerschmitts away from the bombers and was pursued by these fighters into the direction of Gouda. Over Moerkappelle the lonely Dutch fighter was forced to enter into a dogfight with these adversaries. The pilot managed to destroy two of the Bf-110's, but after the pilot had received two serious belly wounds he had to make an emergency landing. When the pilot [decorated for his brave action with the Bronzen Leeuw] climbed out of his plane it was shot up by the remaining Messerschmitts.
The other six Messerschmitts had been chasing both T-V bombers and the other two fighters. Three of the Bf-110's managed to shoot down one of the bombers, although the tail-gunner shot down one of the enemy planes too. Two men on board the bomber were killed. One of the two Fokker D-XXI fighters was pursued by the three remaining Bf-110's. In the vicinity of Leiden he managed to shoot down one of the Bf-110's. Then his Fokker was shot up so badly that the pilot decided to bail out. Upon the release of his canopy he looked in his rear-view mirror [of which the D-XXI had two] and witnessed to his astonishment that the canopy had hit his closest chaser full in the engine, after which the German plane went down and crashed. When the Dutch pilot had decided [upon this success] to stay in his plane and fly it home, a [Dutch!] AAA shell exploded under his plane and threw him out! He landed safely on the ground by his parachute, but was badly wounded. He would survive his wounds [also he was decorated with the Bronzen Leeuw]. The remaining two Dutch planes landed safely on Schiphol later. Three Dutch planes had been lost against a German loss of five. The Dutch losses were however irreplaceable; only one medium bomber was left after this mission ...
Another event that - still today - is remembered by many elder citizens of Rotterdam, was the moment that one of the tall ships of the Holland-America line [HAL] was set ablaze. The Germans had used the ship [SS Statendam] to shelter some machinegun positions. These attracted the Dutch attention and soon mortar and machinegun fire was aimed at the German positions on the ship and the adjacent installations. At around 1600 hours fires broke out and the ship itself caught fire too. The Germans quickly evacuated the vessel that would continue to burn until well after the capitulation. Many pictures of the scene were taken by both the Germans and the Dutch.
The Germans had meanwhile grown doubts about the chances of keeping their bridgehead on the northern bank of the Nieuwe Maas in Rotterdam. At the Student staff the option of withdrawal from the northern bridgehead was weighted. This perception in itself shows the lack of German comfort with the entire southfront situation. In stead of growing more confident as a result of the gained successes at Alblasserdam, Dordrecht and Moerdijk during the second day, the Germans considered these counter measures preludes of more serious things to come. Since the air-bridge with Germany stalled all along and basically only limited reinforcements could arrive [amongst which a battalion of 72.IR], Student felt more confident in redeploying his efforts around Dordrecht and Alblasserdam. When he spoke to Lt-Col Von Choltitz [commander of III./IR.16 and the bridgehead at Noordereiland] about this, the first convinced the General that he would do his utmost to hold on to the defence on the north side of the bridges. General Student did therefore not instruct Von Choltitz to withdraw but rather sanctioned a possible withdraw beforehand should Von Choltitz consider the situation - at some point - in favour of such evacuation. Von Choltitz was however informed that any further reinforcements were not to be expected.