Classic Aircraft profiled every issue -

Issue 10 - de Havilland Mosquito: 10,000 Cookies! The Light Night Striking Force

The early days of Oboe

The story of the LNSF is one that began in late May 1943 when 2 Group ceased to be a part of Bomber Command. Thanks to the foresight of Don Bennett, two of the group’s Mosquito units, 105 and 139 Squadrons were transferred to 8 Group, better known as the Pathfinders. The seeds were now sown for a new approach to the bomber command offensive making use of the Mosquitos’ speed, range and ability to pack a relatively undetected punch against an enemy who was often unaware of their presence until it was too late.

Mosquitos had been a part of 8 Group since August 1942 when 109 Squadron was transferred to it from the WIDU. The squadron had been quietly working in the background developing and testing Oboe, initially using the Wellington IV, but the equipment did not like the transition to the Mosquito. Problems with the equipment were not fully resolved until June 1943 but Bennett’s impatience and the keenness displayed by the crews of 109 Squadron resulted in Oboe entering service before it was completely shaken down. At 1755hrs on the December 20, 1942, Sqn Ldr H E Bufton and his navigator Flt Lt E L I Fould led six Mosquitos against the Lutterade power station.  On approaching the target, it was Bufton who dropped the first Oboe-aimed bombs along with two other crews from the small formation. The Oboe transmitter in the remaining three aircraft failed to work properly and they bombed elsewhere, a familiar story to those who had been working on the project for many months. Post attack reconnaissance flown the following day over Lutterade was unable to establish whether the Oboe attack had been successful because of craters from a previous raid. However, local reports stated that nine bombs fell in open country approximately a mile from the power station and very close to a large area of housing. The system would prove to be invaluable as the war progressed and, by June 1943, 8 Group introduced 105 Squadron as its second Oboe-equipped unit.
139 Squadron’s motto ‘We destroy at Will’ was very appropriate since receiving its first Mosquito IV back in June 1942. Twelve months later, the squadron was doing just that and, on June 13/14, 1943, 13 of them set out to bomb Berlin, Dusseldorf and Cologne for its first operation for 8 Group. The raid was a little bit of an anti-climax as all three cities were cloud-covered and only estimated positions were bombed. What was significant about the raid was the fact that all returned safely, without harassment by night fighters or flak, in half the time that a four engined heavy would have taken.
After gaining further experience flying ‘nuisance’ raids during June and into mid-July, 139 Squadron was tasked with dropping Window ahead of a large raid for the first time. The target was Essen on July 25/26 with 705 aircraft taking part including 19 Mosquitos at the front, flying alongside the seasoned PFF crews. As the target was approached, the Mosquitos began dropping Window (thin strips of metal foil) on their first run and then went around again to bomb the target. Four nights later, the squadron’s Mosquitos went one step further and dropped Window over Hamburg ahead of the marker crews.

Spoofing!

Another new tactic thanks to the increased involvement of the Mosquito was the introduction of the diversion raid or ‘spoofing’. The first time this was tried out was on the night of August 10/11 when the main force of 653 attacked Nuremberg. Meanwhile, just nine Mosquitos carried out their ‘spoof’ on Mannheim, dropping Window on the run in and also, for the first time, dropping TIs (Target Indicators) as well. The small force then made two extra runs on the target, dropping HE as they went. While losses were average on the Nuremberg raid, the effect of the diversion could not be fully gauged, but on the night of August 17/18, the spoof certainly made a difference. The target on this occasion was Peenemünde and if the enemy’s night fighter controllers got a sniff of this target being attacked, then most of the Luftwaffe’s finest would be directed towards them. 596 Lancasters, Halifaxes and Stirlings headed for the German Research Establishment while eight Mosquitos set course for Berlin. Once over the German capital, the first two of three waves were already preparing to attack Peenemünde, completely unmolested by the enemy except for local flak defences. This could be credited to the highly successful diversion by 139 Squadron who had duped the enemy fighter controllers into thinking that Berlin was the main target. To the enemy’s credit, they reacted extremely fast when they had realised their error and the third wave of bombers would bear the brunt of the night’s losses; but it could have been so much worse. Even 139 Squadron did not completely get away with it, losing two aircraft by the end of the night. Fg Off A S Cooke and Sgt D A H Dixon in Mosquito IV DZ379 were intercepted by a night-fighter and shot down near Berge, killing both crew instantly. The second loss was more fortunate for the crew when Flt Lt R A V Crampton and Fg Off P L U Cross were both injured after DZ465 crash-landed at Swanton Morely. When it was the turn of the bombers to hit Berlin again on the night of September 31/1, several of the crews reported seeing white flares along the route in and out of the target. These were presumed to be enemy fighter flares to help guide the Wild Boar crews towards the main bomber stream. A dangerous game of cat and mouse had been initiated so as to counteract the threat of the Mosquitos on the next trip to Berlin on September 3/4 dropped their own White Drip flares at intervals, effectively marking a false route away from the main force.
This tactic worked well and the Mosquitos were now being stalked by night fighters but the performance of the aircraft and crew were more than up to the job of out-manoeuvring the enemy.

Throughout September 1943, the Germans were well aware of how the Mosquito was being used by 8 Group. Because of the aircraft’s habit of operating at higher altitudes, the enemy quickly developed flak which could burst at up to 30,000ft. Two of 139 Squadron’s Mosquitoes were coned over Dusseldorf and the subsequent barrage meant that both had to return to England on a single engine. Sqn Ldr D A Braithwaite was coned over Brandenburg on September 14/15 en route to Berlin. The Mosquito was hit at least 10 times by flak but, typifying the spirit of 139 Squadron, Braithwaite continued on to bomb Berlin and then returned home safely to Wyton.

By late October, Bennett found himself with a surplus of Mosquito crews which were more than sufficient to form a third flight for 139 Squadron. However, Bennett decided that the surplus would be best used to create a new unit. Eight crews were transferred from 139 Squadron to create 627 Squadron on November 12, 1943 at Oakington.

The New Year brought another new squadron to the 8 Group fold when 692 Squadron was formed at Gravely on November 1, 1944 under the command of Wg Cdr W G Lockhart. The new unit did not manage to contribute to the fight for most of January but 139 and 627 Squadrons managed 184 successful sorties between them. One of these was a particularly effective spoof on Berlin where TIs and window were dropped causing the bulk of the night fighter force to assemble over the capital while the main force plastered Stettin.

GH and H2S

By this time, 139 Squadron was being slowly steered towards becoming 8 Group’s main marking squadron for the LNSF. Experiments with GH had been disappointing but one Mosquito was modified to take H2S and this flew operationally for the first time to Berlin on January 27/28. Five days later, the same aircraft led a small force of Mosquitos, including one from 692 Squadron on its first operation, on another raid to Berlin using H2S. The biggest raid of the war so far on Berlin on February 15/16 owed part of its success to Sqn Ldr S D Watts and an accomplice. Watts was busily laying a false route out of the target and, while checking to make sure his flares were being backed up, was amused and surprised to see a German aircraft reinforcing the flares behind him.

The Mosquito was continually being experimented on to find out the limit of its capabilities which were still a long way from being completely exhausted. A proposal was put forward in April 1943, suggesting the Mosquito was more than man enough to carry a 4,000lb single bomb load; namely a ‘Cookie’. The bomb bay was easily modified but the centre of gravity, thanks to the extra weight, was causing a few headaches, and in the case of the Mosquito IV and IX, was never completed eradicated. Regardless of the C of G issues, a pair of modified Mk.IVs were delivered to Oakington for 627 Squadron but for some unknown reason were immediately transferred to Gravely for 692 Squadron. The two converted Mosquitos were ready for action and, on February 23, 1944, Sqn Ldr Watts and Fg Off C Hassell took off for Düsseldorf at 1903hrs. Right behind them was Flt Lt V S Moore and Plt Off P F Dillon, setting the stage to see which crew would be the first drop a Cookie from a Mosquito. 105 Squadron provided the small marking force and, at 2045.30hrs, Watts navigator/bomb aimer pressed the bomb release first followed by one minute later by the bomb from Moore’s aircraft.

With still only three squadrons making up 8 Group’s LNSF, the Mosquitos still managed to fly 509 sorties of which 489 of them were successful. One particularly successful spoof operation was flown by 627 Squadron on March 1/2. While the main force attacked Stuttgart, 11 Mosquitos created an elaborate diversion all the way to Munich, resulting in just four bombers being lost out of a force of 557 aircraft.

Growing in numbers

The LNSF continued to swell when 571 Squadron was formed at Downham Market on April 5, 1944. The squadron was to be a two-flight setup at first but some of its intended aircraft were transferred to 105 Squadron which was now at Bourn. 105 Squadron now gained ‘C’ Flight as there was now a higher priority being placed on smaller targets within Oboe range and Bennett was well aware of the pressure being placed on his two Oboe-equipped squadrons.

571 Squadron took part in its first operation on April 12/13 when two crews were among 39 Mosquitos in an attack on Osnabrück. This size of raid was now becoming the norm for the LNSF and April 1944 in particular included some very large Mosquito raids. 35 attacked Hannover at the beginning of the month, followed by 41 against Cologne and another 40 attacking Essen on April 8/9. The raid on April 13/14 saw Mosquitos carrying Cookies to Berlin for the first time. The extra fuel needed was carried in a pair of 50-gallon drop tanks which were neatly fitted under each wing.

On April 15, the LNSF shrunk slightly when 627 Squadron was transferred 5 Group to see the remainder of its wartime service out at Woodhall Spa. Despite the drop in manpower, the LNSF still managed to carry out 553 sorties with only the loss of a single aircraft.

As D-Day approached, Bomber Command were becoming increasingly pre-occupied with targets in Northern France. This did not stop the LNSF continuing to carry the fight to Germany which included another seven attacks on Berlin. With still only three squadrons, the LNSF managed to fly 661 sorties but this figure was would be on the rise again with the arrival of another squadron on August 1, 1944. 608 Squadron was re-formed at Downham Market with the Mosquito XX and was destined to operate from the Norfolk airfield for the remainder of the war. Only four days later, Sqn Ldr J D Bolton flew the squadron’s first operation to Wanne-Eickel. 608 Squadron were in the thick of the action from the start and one very successful attack on Cologne on August 23/24 saw ‘an enormous explosion lasting 45 seconds lit up streets and buildings’. It did not go all the LNSF’s way that night, with one 692 Squadron aircraft crashing en route, killing both crew and Flt Lt S O Webb in 608 Squadron Mosquito XX KB242 being attacked at least four times by a night fighter. Webb and his navigator, Plt Off Campbell, were lucky to make it to Woodbridge uninjured.

The LNSF expanded again on September 5, when 128 Squadron joined the fold after re-forming at Wyton. Just five days later, the whole squadron joined the fight when it was part of a 47-strong force which attacked Berlin. The capital was attacked by the LNSF again the following night with another 47 Mosquitos led by 139 Squadron. It was not a good night for the Upwood-based unit which only managed to drop TIs from two of the nine aircraft designated. Enemy flak was also alarming accurate this night, resulting in the loss of Flt Lt J A F Halcro and Flt Lt T J Martin, both RCAF; their Mosquito crashing at in the Horst Wessel district of Berlin. Another 139 Squadron aircraft, flown by Plt Off H A Fawcett was hit by flak during his bombing run which knock out an engine and damaged the hydraulics. Unable to open the bomb doors or lower its undercarriage, Mosquito XX KB227 limped back to Woodbridge where Fawcett executed a perfect crash landing with only minor injuries to himself and his navigator, Fg Off P L U Cross DFC.

With its Overlord commitments declining, the heavy squadrons were now back in force against Germany and the LNSF were called upon to continue ‘spoofing’ and dropping Window on targets for 8 Group. Kiel and Frankfurt were among the targets attacked with a raid on September 15/16 being particularly successful. While 490 aircraft attacked Kiel, nine Mosquitoes ‘spoofed’ Lubeck with Window and TIs and followed this by bombing the port. Another 27 Mosquitos attacked Berlin, not to mention 7 others which Windowed Kiel in front of the main raid.

142 Squadron was the next unit to be reformed with Mosquito XXVs at Gransden Lodge on October 25, 1944. Two aircraft were part of a 59-strong Mosquito force on Cologne four days later and two more were over Berlin, joining 60 other Mosquitos in a two-phase diversion. Poor weather disrupted operations during November but this did not stop the LNSF from attacking Hanover nine times in favour of Berlin. Oboe-guided raids, thanks to the advancing allies could now be extended further east putting cities such as Stuttgart well within range. On November 5/6, 65 Mosquitos, led by Oboe and backed up by 139 Squadron, hit the city in two phases 3½ hours apart. Many of the crews involved, all of whom returned safely, reported huge fires and large explosions throughout both phases.

By early December, an average of over 60 Mosquitos were attacking main targets and this was set to increase, with the addition of another squadron on December 16, 1944. 162 Squadron was re-formed at Bourn and along with several new crews for 139 Squadron were the first to be sent on ‘Siren Tours’ to gain H2S experience. These tours covered every corner of Germany and involved dropping a single 500lb bomb on three or four separate targets. While all crews benefitted from these long trips, it also resulted in keeping ground defences on continuous alert and resulted in many lost man hours in the enemy factories without causing great deal of damage. The first sirens were flown on December 23/24 against Bremen, Hanover, Münster and Osnabrück. The same night, 52 Mosquitoes attacked Limburg rail yards and another 40 attacked Siegburg while the heavies rested.

New Year’s Day 1945 saw a classic example of the Mosquito in action when 17 of them attacked railway tunnels between the Rhine and the Ardennes battle area. The object of the exercise was to prevent German forces from being reinforced and in broad daylight and with a ‘cookie’ apiece, the Mosquitos dived to 200ft dropping their short-fuse delay bombs into the entrances of the tunnels. One crew, Plt D R Tucker and Sgt F A J David, of 571 Squadron, found three tunnels and after making a dummy run on each, in full view of the local villagers, dropped their cookie perfectly into the entrance. Tucker banked round to view his handy work and saw that the whole tunnel had erupted, causing the hillside to collapse into the path of an approaching train.

The final piece of the 8 Group Mosquito jigsaw was in place on January 25, 1945 when 163 Squadron was Reformed at Wyton. This now meant that Bennett could easily muster 150 aircraft at a moment’s notice without putting up a maximum effort.
The ever-increasing strength was put to good effect on the February 1/2, 1945 when 176 Mosquito sorties were flown on eight separate targets. Ludwigshafen, Mainz, Siegen, Bruckhausen, Hanover, Nuremburg and Berlin were all hit; the latter involving 122 Mosquitos. Berlin would suffer mercilessly at the hands of the LNSF during the final months of the war and, from the February 20/21, the capital was attacked on 36 consecutive nights. Averaging 60 Mosquitos per raid, 2,538 sorties were flown to Berlin of which 2,409 were successful. 855 cookies were dropped on the city during this period alone and the LNSF continued to bomb Berlin right up to arrival of the Russian forces in late April 1945.

The Mosquitos of 8 Group had performed exceptionally well and, since its formation, they had flown 28,215 sorties with the loss of just 100 aircraft (0.4%), 70 of which were lost by 139 Squadron alone. Approximately 26,000 tons of bombs, of which nearly 10,000 of them were cookies, were dropped on Germany; a remarkable achievement for a small unarmed twin-engined bomber made of wood.

‘The value of the Mosquito attacks as a supplement to the attacks by heavy aircraft is unquestioned and their contribution to the success of the combined bomber offensive was both significant and praiseworthy’ Bomber Command Review 1945.