4.1
May 13
North
The 1st German cavalry division arrived on May 13 for the Wons-line. The last units of the border battalions retreated behind this line in the late afternoon of the previous day. The Wons line was presupposition of Kornwerderzand. The line was approximately 7 kilometers long and lay between Makkum and Zurich in Friesland. There were small concrete, bunkers, last ones just finished in April. Thanks to the martial law the planned inundations were implemented. The positions were defended by a reinforced battalion, supported with 7-field guns and 12 cm howitzers, both made by Krupp and a battery of 2 cm AA Scotini in three groups along the line. After an introductory air raid and artillery bombardment, the German attack followed. The Dutch troops were pushed back into the outposts around noon. The retreat from the outpost nearly resulted in a general retreat, but thanks to the modern field telephone lines and wireless, this could be averted. The commander ordered an artillery bombardment on the advancing German troops as to confirm his orders.
The IJsselmeer flotilla, including the old gunboats Friso and Brinio, gave also fire support each with four 10.5 cm guns.
Center and Grebe-line
The 13th also saw battle on the entire line of the Grebbe Line. Attacks on the out posts were repelled the previous day, but now concentrated large scale attacks on local outpost were made with success.
The 4th Hussars Regiment of the 2nd Army Corps already had the necessary action seen and made with reasonably success numerous delay actions with relatively few losses, but now had to retreat behind the Grebbe line.
In the afternoon after several out post were finally overrun and the main line on the Grebbeberg, it self become the center of gravity of the attacks. The Germans managed to penetrate the defense on two locations. During the attack they experienced more opposition, and a complete breakthrough failed. How ever in the evening the East side of the Grebbeberg was in German hands. Thanks to the modern fixed and wireless communication and artillery observation, Dutch artillery managed to fire effectively in support for the infantry. Communication and infantry artillery coordination problems were less frequent as in the days before and the Dutch artillery support improved considerably like elsewhere on this day.
At the Betuwe -line South of the Grebbe-line the defending units successful repel all the attacks.
Southern front
The German 9th armored division battled its way in the direction of the Moerdijk bridges. The Peel division retreated West to Zeeland and to the Merwede bridge were they made contact with he Border battalions. The Light division continued to fight the 9th armored division which was also fighting the French armored units. How ever at noon it become clear that the French were slowly retreating South, instead of maintaining contact whit the Dutch Units North of them. The French, had orders to retreat South leaving the Dutch Light Division.
In the afternoon the forefront of the 9th armored division, the spire of the German 26th corps, finally reached the Moerdijk bridges.
The Southern shore was in Dutch hands while the Northern shore were still in the hands of the German paratroopers.
The Light Division, who engaged the German armor so successful were directed to cross the Bridge at Keizers veer, and destroy the bridge behind them. After that they advanced to the bridge over the Noord and to support the 3rd and 6th border battalions with the aim to repel the para troopers at the Dordrecht battlefield.
The Light division was ordered North at the end of the day after the reports of their engagement with German armor and the imminent retreat of the French units nearby. The DAF armored cars and Landsverk L-60 tanks proved to be very capable vehicles and in very capable hands. Only two L-60 were lost, one due to technical problem, one by enemy fire and five armored cars of which three due to fighting. The artillery and supporting lorries how ever suffered more battle casualties, in most case inflicted by the numerous air raids of the Luftwaffe, not to mention casualties of the Dutch infantry after now three day continuous fighting.
The French retreat to the South after relative successful engagements with only smaller and lighter surprised the German filed units.
Confronted with an advancing enemy and retreating French the reason to keep the Moerdijk bridges intact was gone.
In the eveneing og the 13th, General Reijnders gave the order to destroy the bridges on the South side and retreat behind the inundations around Willemstad.
While the first units of the German 26th corps engaged the defenders two pillars of each bridge were blasted. Literally in the face of the enemy.
The Moerdijk bridges (and surroundings) were also shot at by our artillery from the island of Hoeksewaard giving support while the infantry retreat towards Willemstad. The modern Bofors, 10,5 cm guns could reach nearly the entire island and gave also fire support to the troops around Dordrecht.
On the island of Dordrecht many battles were fought with the German paras. Border battalions, such as 3rd border battalion, were still in action far from their starting place. The ad-hocs of the Pontonniers and Torpedist (engineers) are also involved in the battle around Dordrecht.
Rotterdam
The fighting continued in Rotterdam as well. Dutch artillery reinforced the troops at Waalhaven and start shooting at the improvised air field in front of the Fijenoord Stadium on which the Germans depended for their supplies. Dutch infantry take the initiative and advances to the Maas-bridges and Noorder-eiland. About 600 men, commanded by Oberstleutnant Von Choltitz, equipped with a few 3,7 cm AT guns, heavy machine guns and mortars, defended this strategic stronghold with all their power. In the Afrikaander and Hillesluis neighborhoods the advancing Dutch units were engaged by German para troopers, and during the entire day an intense and confusing city battle erupted.
At center of Rotterdam the Dutch troops tried to cross the bridges from the North side which they retake the previous day. The attack include heavy shelling of the Noordereiland and the ferry of troops by barge to the other side at Katendrecht. The reinforcement under fire reach Katendrecht and are able to break out and make contact with the advancing units from Waalhaven. The attack to cross the bridges was supported by DAF and Landsverk armored cars, with 3,7 cm Bofors guns. The Germans responded to their appearance with some well aimed anti-tank fire, crippling one of the cars and heavy machine gun fire. Although the damaged car was able to retreat, it could no longer contribute to the assault. The other armored car continued to support the assault. The assaulting group managed to reach the South end of the bridges but in the ensuing street battle the Dutch were not able to hold a strong point on this side. At a sudden point the Germans were able to enfilade the bridges with heavy machine gun fire which prevent the reinforcements of the Dutch troops at the South end, when the second armored car was destroyed by anti tank fire of the Germans the Dutch retreated. After this dramatic fight, that took hours of intensive close-combat action, no further offensive action would be developed against the bridges.
A British-Dutch- German air battle
Most likely one of the confusing and large air battles above Dutch airspace and during the this period of the war.
In the early morning hours of the 13th between 0430 and 0700 hours, Stuka's assaulted the Dutch artillery and infantry positions around Alblasserdam, units advancing to the German units on the island of Dordrecht. But this time they would meet some opposition in the sky.
In the evening of the 12th the RAF had planned a strafing mission of six Boulton Paul Defiants of 264th Squadron and six Spitfires of 66th Squadron along the Dutch coast. As this combined squadron approached the Dutch coast they were treated on Dutch anti-aircraft fire before identified as being allied airplanes, fortunately without sustaining any damage. They proceeded south towards the Hague and Rotterdam. Then they spotted the Luftwaffe Stuka's South-East of Rotterdam.
Just a bit later from airbase Valkenburg six of the twelve remaining LVA Hurricanes with and six G-1 were started on a mission to provide air support of the infantry units fighting around Dordrecht, this was accidentally in the same direction as the British flew.
The Stuka's were of the 12th squadron of LG1. As they dove towards Dutch positions at Alblasserdam suddenly the twelve British fighters appeared.
A huge dogfight unfolded when the Germans got fighter back-up after a red flare was launched from the leading Stuka. The arrival of Messerschmitt Bf-109, 24 to 27 of JG26 fighters meant that the kettle was put on the fire. At the same time the Dutch planes flying behind the British get engaged. The dogfights gradually expanded to the skies over Brabant.
After the clash between the three forces,together about 52-55 planes, six German Stuka's, four Bf-109's and five of the vulnerable British Defiant's and three G-1's had been destroyed - killing most of the crews. It is a miracle that the British and Dutch airmen managed to escape total annihilation after being confronted with the overwhelming German force and even managed to take out more enemy planes than they suffered own losses.
Air force.
Many planes had sustained heavy damage from ground fire and air duels or suffered severely from worn parts and guns. Yet the very dedicated and professional ground crews managed to patch up many of the planes. At the 13th a considerable number of fighters, Fokker D-21, Hawker Hurricanes and Fokker G-1 bomber/fighters and even nine Douglas 8A, would be ready for service, although many of the pilots had to be laid to rest. Nearly all of them had been active for four full days of war and had seen their beds for only a few hours.
The D-XXI's fighters would be assigned to a number of escort-flights. Three times this day they accompanied a flight of four Douglas 8A bombers to the Grebbeberg. Each time a total of 1,600 kg bombs were dropped on the German positions.
The first two sorties were executed in the early morning and the second mission was flown later, around noon. Both times the flights reached the Grebbeberg without incidents and all times they returned home safely after successfully bombing and strafing the enemy.
The bombers attacked German artillery positions near Wageningen. During the second and third mission, they bombed German troops and equipment close to the road Wageningen - Rhenen.
Also four C-10 biplanes made two sorties that that day strafing and bombing advancing German troops more at the North sector of the Grebbe line.
Four G-1 fighter-cruisers, which had been sent to the Grebbeberg on a strafing mission, followed shortly after the last bomber mission had been executed. The strafed German troops on the ground. On their way back, these two fighters collided with a patrol of Bf-109 fighters in the over the city of Woerden West of Utrecht. One Bf-109 was shot down. Both G-1's had sustained extensive damage due to previous German ground fire.
Since the start of the conflict diplomatic envoys were out to London and Paris for military support. With not much response except the French units in Brabant. At the 12th the request for support to London was made more specific. General Best, commander of the Dutch air branch, urged to reinforce the LVA with at least three RAF squadrons. Initially this fall on deaf ears in London, but after to arrival of 1100 German imprisoned paratrooper on the early morning of the 13th and the information that there were some 700 more on their way made some leverage.
After the initial bombardment of Schiphol at the 10th and the destruction of several KLM planes the KLM moved all of their remaining DC2's and DC3's planes with what ever they could carry to the UK.
On the 13th the KLM was ordered to load five Merlin engines and supplies with the planes needed to carry this and fly these engines to air base Valkenburg. Later this day this support was even enlarged and two whole RAF Hurricane squadrons would fly to auxiliary airbase Buiksloot near Amsterdam North
There were some difficulties, the LVA changed the octane level to 100 for their new airplanes but the MG's of the Dutch airplanes used 7.7mm while the RAF used 7.6 mm ammunition.
Dusk of the 13th six KLM planes landed on Valkenburg airbase with four spare Merlin engines, British MG ammunition and one RAF squadron of 12 Hawker Hurricanes.
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