Assault on Fornebu

This text relies heavily on the splendid Norwegian book "Fornebu 9.April" by Cato Guhnfeldt.

A minute by minute account of the event can be found here.

Background

An important part of operation Weserübung (the invasion of Norway and Denmark) was the seizure of three important airfields by paratroopers. It was the airfield outside Aalborg in northern Denmark, Sola outside Stavanger and Fornebu outside Oslo.  The field at Aalborg was important as an advanced airbase with land connection to Germany and a staging point on the way to Norway. Sola was the biggest and best airport in Norway with a perfect position to control the sea approaches to southern Norway. Fornebu was still under construction, but nearly finished.

The defense of the field

In the spring of 1940 Fornebu was base for Jægervingen, the fighter wing of the Norwegian army air force. It consisted of a squadron of Gloster Gladiator, of which only five where operative in the early morning the 9th of April 1940. The defense of the airfield was the ground crew of Jægervingen, with three AA-machineguns in pits at the eastern edge of the field, and two placed out in the open at the north end of the field. A few hundred meters west of the runways a searchlight platoon of the Oslo air defense was positioned. They had two AA-machineguns for close defense, but limited sight over the field due to a hill.

The Fallschirmjäger assault (airborne assault)

340 men are to be dropped at Fornebu by 29 Junkers Ju52 from 5. And 6.Staffel from Kampfgeschwader z.b.V. 1. This Kampfgeschwader is an ordinary air transport unit of Luftwaffe and has been training together with the paratroopers. The commander is Oberstleutnant Karl Drewes (44). In addition to the 29 transport aircrafts there is one Ju52 designated for signal communication and intelligence. A staffel of eight Me110 fighters, under oberleut. Werner Hansen, will provide protection and ground support for the fallschirmjägers.

The units involved are:
Commander Hauptmann Erich Walter (36)
Staff of 1.Bataljon under Oberleutnant Götte
1.kp under Oberleutnant Herberth Smidt
2.kp under Hauptmann Gröschke

They start from Schleswig at "Zeit Y", 4.30 am. The weather forecasts are less than good. The weather is cloudy and with fog from the sea up to 600m. Only half of the aircrafts have any person well trained in instrumental flying on board. A fact that Drewes has complained over repeatedly during the preparations. Nothing has happened though, and the demand for such personnel is very high due to the vast number of aircrafts heading for Norway in the 9th of April.

Over Skagerak the aircrafts has trouble to see each other at times. And an aircraft near the rear of the formation reports that two aircrafts behind it are missing. The fear in the command aircraft is that the two Junkers has collided in the clouds. Drewes, who has been skeptical over the possibility of this mission, orders the aircrafts to turn back. The commander of the Fallschirmjägers, who flies with the command aircraft, protests violently, as he doesn’t find the conditions totally hopeless but Drewes doesn’t change his mind. So with the Norwegian mountains in sight 26 aircrafts turn back while three aircrafts don’t catch the order and continues toward Oslo. A message is sent to the "Transportchef Land" at the High quarter in Hamburg; "Kehre wegen Schlechtwetter um" (Turns due to bad weather).

As one can see there is only one missing aircraft now. This aircraft might have been shot down by a British Blenheim, sighted by another of the Junkers, or flown into the ground by mistake due to the fog.

The three aircrafts that continues toward Oslo are two with the battalion staff and the special communication aircraft. It is ironic that the communication aircraft will be among them who doesn’t catch the message. Another possibility is that they ignore it because of their special status.

Another unit that continues on its way north is the eight Me110 that are supposed to support the assault.

The first wave of airlift

20 minutes after the paratroopers comes the first wave of the airlift. It is the 53 Ju52 from KGr z.b.V. 103, under Hauptmann Wagner, with soldiers from II/IR324.

The formation flies at the altitude 300m until they reach the fog over Skagerak, then they go down to sea level. All aircrafts have crewmembers well trained in instrumental flying and they manage to keep on the right course. The transports flies in groups of three, but during the long journey the groups became widely separated. 

At 07.33 a message is received with an order to turn back. The message states "Wegen wetterlage ruckflug Schleswig" (Due to the weather fly back to Schleswig) and is signed Fliegercorps X. Wagner finds this order less reliable. It doesn’t state which formation it is directed to, and it is not signed by the "Transportchef Land" which is the nearest commander over KGr z.b.V. 103. It could be a message directed to another formation or it could be a false message. As they were close to the target and the weather showed signs of improving he decided to ignore the order. Some of the aircrafts in the group did return though.

When the headquarter of Fliegercorps X received the message from Drewes that the Paratroopers were turning back, the commander of X Fliegercorps Hans Giesler wanted to abandon the airborne assault on Fornebu. The commander of transport groups (Transportchef Land), von Gablenz, claims stubbornly that his forces can take Fornebu without the paratroopers and that it would be worthwhile to give them a try. Giesler doesn’t want to change his mind though, so von Gablenz has to give up, and the order is sent. One might speculate on if it is the reluctance of von Gablenz that leads to the "bad" formulation of the order.

On their way north they meet the returning transports of the abandoned Fallschirmjäger assault. The returning pilots signals to them by tipping the wings and some more of the aircrafts returns, while other think the signal is just a greeting.

Around 8 o’clock some of the aircrafts begin passing straight over Höytorps fort near Mysen at low altitude. This is probably because they have chosen the town Mysen as a reference point on the route to Oslo. They are by now split up in widely separated groups of three. The anti aircraft defense at the fort consists of 10-12 8mm Colt machine guns. They were alarmed at 7.00, and when the German aircrafts begin to pass they are fired at. The machine guns soon begins to malfunction though. This turns out to be because they have got the wrong kind of ammunition. Little damage was done to the aircrafts, except that one engine began to smoke.

Other aircraft follows Oslofjord and passes Oscarsborg fortress and the place where Blücher sank. The AA-defense of Oscarsborg fires at them but with no noticeable result. There is still a lot of oil burning on the water, and the German soldiers understands that there will be armed resistance.

The Norwegian fighter squadron (Jægervingen) at Fornebu

After a night disturbed by air raid alarms and the information that there are foreign warships in combat with the coastal fortresses in Oslofjord, Jægervingen is woken up shortly after four o'clock in the morning to make ready the aircrafts. The weather is cloudy, but in the morning the clouds begins to break up over Fornebu. Further out on Oslofjord the cloud cover is heavier.

At five o'clock two Gladiators starts on air patrol. One of them intercepts a Dornier (probably a Do17) and attacks it, but after a while it manages to sneak away in the clouds. More patrols follows, but no more enemy aircrafts are intercepted. A report is received from Malmö (in Sweden, about 500km south) about 15 aircrafts heading north at 06:18 (I have seen no information about who this report came from). At 6:30 Jægervingen is informed. Possible arrival time to Oslo is calculated, and it is decided to send up the Gladiators in good time to be able to intercept in case Oslo is the target. 

At 07:05 the five Gladiators that are ready takes off. They flies south toward Dröbak, and patrols in that area. Half an hour later two more Gladiators (suffering from bad sparking-plugs) are fixed and takes off.

At 07:35 the Norwegian air patrol, flying at 1800 meter, sights 8 Me110 heading north 5-600 meters below (just above the clouds). It is the German Me110 Staffel with the mission to assist the paratroop assault on Fornebu. Lt Tradin orders break of formation and independent selection of targets. A long air combat begins as more and more German aircrafts turns up. There is no absolute evidence on how many aircrafts are shot down by the Gladiators, but 2 Me110 and 2 He111 seems to be a common opinion, against one Gladiator forced down (nbr.427). As the first two Gladiators tries to land to fill new ammunition (at about 8 o'clock) they are attacked and destroyed by the Me110 (nbr.419 and 425). The other Gladiators are ordered not to land at Fornebu, and as their ammunition is finished they flies away and  lands at different places. Only one ever flies again (nbr.423).

After destroying the Messerschmits turns to the AA defences. The crews of two unprotected machineguns at the north end of the field is chased away rather quickly, and one man is wounded. They don't manage to chase away the crews of the three AA-machineguns in pits south of the terminal buildings though.


Picture of one of the gun pits at Fornebu. Taken during the winter 39-40.

The mission of the German Me110 staffel was to protect and assist in the airborne assault of Fornebu. As described above this assault never materializes. This is however not clear to Werner Hansen, the commander of the staffel. Anxiously he flies back and forth over the field without seeing any transports. Finally a few Ju52 arrives, but instead of dropping paratroopers they just circle around the field and suddenly goes in for landing. This is not the paratroopers, but aircrafts from the follow up wave. The commander, Richard Wagner, supposes that the field is secured and goes in for landing. He will have to pay for this decision though. The aircraft is hit hard by the Norwegian machineguns and he and four of the soldiers in the aircraft are killed. The pilot breaks off the landing and flies back to Denmark. A second aircraft lands just behind and has greater luck. They land without losses. Now the Me110 runs out of fuel so they have no choice but to land. A few more Ju52 follows. They unloads at the western end of the field and the Norwegian machineguns are unable to disturb them much. Soon the Norwegians are completely out of ammunition and at about 9 o'clock they leave Fornebu. They stop at Lysaker, on the road to Oslo, and waits for reinforcements.



Map over Fornebu with the situation after the initial German landings. The aircrafts out on the runways and other irregular places are wrecked. The map is from "Fornebu 9:e April".

The "Battle" for Oslo

About five minutes after the first German aircraft landed at Fornebu, the Guards battalion (Garden) was alarmed. It was 8:26 and the battalion commander orders the only available unit, kp.2, to Fornebu. Kp.3 were demobilizing and must be reorganized, and kp.4 had been ordered south to take care of the survivors from Blücher earlier in the morning. Half an hour later they are ready to march, but the busses sent for didn't turn up until 9:40, when another half hour had passed. Had they taken the direct route to Lysaker then, where the AAmg platoon from Fornebu still waited, they would still have been able to seal off Fornebu and possibly disturb the German build up. Lysaker is a key to the approach to Oslo from Fornebu, with a bridge over a small river, and with that in Norwegian hands the Germans would have trouble reaching Oslo. Now they decided to take a secondary road further inland, unloading and then advancing on Lysaker by foot. Disturbed by enemy aircrafts and loosing more valuable time trying to coordinate with a company of I.R.5 arriving from Trandum, they don't reach the vicinity of the bridge until 12 o'clock and were not ready to assault the bridge until long past one o'clock. 

 

After the cancelled airborne assault and the order to return,  most of the aircrafts in the follow up wave flew to the airfield at Aalborg in Denmark, which had been secured earlier in the morning by another airborne assault. Many had to make forced landings at various fields in northern Denmark. When the few aircrafts that didn't follow the order to return successfully secured the field, the rest were ordered to follow. At half past ten the German follow up wave finally began arriving at Fornebu, and the Germans began advancing out of the Fornebu area. At 10:55 a German column approached the Norwegian platoon at Lysaker, and they withdrew toward Oslo. The Germans advanced unhindered toward Oslo, and at half past twelve the first Germans arrived outside Akershus.

The commander of Oslo garrison enter talks with the Germans about surrender, and at 14:00 a formal surrender was signed, including all forces under his command. The military schools and headquarters had already been evacuated but the surrender included the Guard battalion, the AA-defences and the airbase at Kjeller, far east of Oslo. In the evening it came to the slightly surrealistic situation that the commander of Kjeller airbase considered his unit as surrendered to the Germans while still behind the defence lines built up during the evening by IR5 along Nitelva, east of Oslo. It is a telling illustration of the confusion of this day that nobody questioned this arrangement! 

Minute by minute account of events at Fornebu during the 9th of April

00:02 Oslo luftvernkommando (AA command) orders "Beredskap 3"  (highest alert) for all anti aircraft units in Oslo.
00:15 First air raid alarm sound in Oslo (no enemy aircrafts turns up though).
00:20 Black-out is ordered but not in effect until much later.
00:45 The pilots and ground staff at Fornebu (Jægervingen) are woken up. Officers are informed that the forts in outer Oslof´jord has opened fire on unknown naval forces. The aircrafts are dispersed on the field.
01:35 All clear sounds in Oslo.
02:00 The Personnel at Fornebu are sent back to bed. They are informed that the fighting in Oslofjord had been with German ships that had been driven into the fjord after a battle with superior British naval forces.

04:0x The personnel at Fornebu are woken up again.
04:10 Oslo luftvernkommando (AA command) orders "Beredskap 3"  (highest alert) again. A multiple engined aircraft is heard over the airfield.
04:13 Air raid alarm and black-out in Oslo.
04:15 "Weserzeit" (invasion moment in the German planning)
04:21 Oscarsborg fortress in inner Oslofjord opens fire on Blücher. The explosions can be heard at Fornebu.
05:00 End of black-out
05:00 The clouds are beginning to break up. Aircrafts can be heard over the clouds. Two Gladiators are ordered up on reconnaissance mission. It is Fk Finn Thorsager (Glad. nbr. 433) and Lt Arve Braathen (Glad. nbr. 425?). Finn Thorsager sights and attacks a Dornier (probably a Do 17 from Fernaufkl.G 120) repeatedly until the Dornier manages to sneak of in the clouds.
Lt Braathens also sights an aircraft but doesn't manage to get within firing distance. His radio doesn't work, and after some searching for the enemy aircraft he lands at Fornebu again.
05:55 Three Gladiators are sent on a patrol mission over inner Oslofjord. It is Krohn, Schye and Waaler. Flying out toward the Dröbak narrows and then returns without sighting any aircrafts. On one aircraft neither the radio nor the machineguns work satisfactory.
06:00 All clear sounds in Oslo. 
Around 6 o'clock the AA machineguns of Jægervingen are made ready. There are three emplaced in newly constructed pits. In addition two light MG received for training purposes are placed at the north end of the field. Unfortunately without any cover at all nearby.
06:30 Fk Finn Thorsager lands again after his patrol.
06:30 Jægervingen is informed that 15 aircrafts heading north passed Malmö at 06:18. Possible arrival time to Oslo is calculated, and it is decided to send up the Gladiators in good time to be able to intercept in case Oslo is the target.
06:43 Krohn, Schye and Waaler returns to Fornebu.
07:05 Five Gladiators starts the patrol decided at 06:30. It is Tradin (nbr.429), Thorsager (nbr.433), Waaler (nbr.427), Krohn (nbr.423) and Schye (nbr.???). They climb to 1000m, then flies south on western side of Oslofjord. After investigating the smoke from the now sunken Bluecher, they patrol around Dröbak.
07:30 Air raid alarm in Oslo.
07:3x Two Gladiators with bad sparking plugs are fixed after half past eight. They start with Lt Braathen (nbr.413) and sgt Luetken (nbr.419). Glad. nbr.419 still have a non working radio. Work is still done on Gladiator nbr.415 when the mechanic is ordered to take cover. Opinion differs on wether he would have been able to fix it before the Germans arrived.
07:35 The Norwegian Gladiator fighters at 1800 meter, sights 8 Me110 heading north 5-600 meters below (just above the clouds). It is the German Me110 Staffel with the mission to assist the paratroop assault on Fornebu. Lt Tradin orders break of formation and independent selection of targets. A long air combat begins as more and more German aircrafts turns up. There is no absolute evidence on how many aircrafts are shot down by the Gladiators, but 2 Me110 and 2 He111 seems to be a common opinion, against one Gladiator forced down (nbr.427). As the first Gladiators begins to land to get ammunition they are attacked and destroyed by the Me110 (nbr.419 and 425). The surviving Gladiators lands at different places. Only one ever flies again (nbr.423).
07:45 Planned time for airborne assault on Fornebu.
08:00 German Me110 attacks Fornebu. Two Gladiators are destroyed on Ground (see above) and the personnel at the two unprotected machineguns are chased away.
08:19 The first Ju52 (with Haubtmann Wagnar attempts to land at Fornebu, coming in from south. Wagner and four soldiers are killed and the aircraft returns to Ålborg in Denmark.
08:20 The second Ju52 attempting to land succeeds without losses, and taxes away to the cliffs at the western end, where the soldiers bails out. Then Lt Lent (later an Ace), flying one of the Me110, lands. He had just one working engine. A few more Ju52 and the rest of the Me110 lands.
08:26 Oslo Samlestasjon (sort of Communication center for Oslo area) informs Garden (the Royal guard) that Germans has landed at Fornebu. The commander of the Guard orders 2.Gardeskp. to Fornebu.
08:33 Three Ju52 with 19 paratroopers and the staff of the Fallschirmjäger company arrives. 
09:00 (about) The AAmg platoon and other military personnel  at Fornebu withdraws. They drives past Germans at the exit of the field without any exchange of fire. The Norwegians withdraws to Lysaker.
09:05 The Commander of the Guard is ordered by H.O.K to force the Germans away from Fornebu, but to not risk his unit in case the Germans are to strong. In that case he would just block the approach to Oslo.
09:50 The searchlight platoon west of the field withdraws over the ice.
10:30-11:00 The main force of the German airborne forces begins to arrive at Fornebu.
14:00 The main part of the 2.Fallschirmjaeger company arrives at Fornebu.
17:50 A British Short Sunderland on a reconnaissance mission over Oslo harbour is shot down by two Me110.