Report by the Air Force Commander on the combined operation against Dieppe - 19 August 1942
General Outline
1.Operation Jubilee was a raid against occupied territory with the purpose of capturing, by assault, and occupying for a limited period, the town of Dieppe. Military tasks in the area of Dieppe included the destruction of local defences, power stations, dock installations - the capture of prisoners and the destruction of the aerodrome installations near the town. It was also intended to capture and to remove German invasion barges and other craft in the harbour.
2.The operation was planned to take place on the first suitable morning for such a landing between 18 and 23 August. The expedi-tion sailed from the area of the Portsmouth Command in a succession of groups starting at civil twilight on the evening of 18 August.
3.The Naval, Military and Air Force assigned to this operation are set out in Appendices.
4.The plan prepared jointly by the three Force Commanders involved a landing on the outer flanks of Dieppe at Orange and Yellow Beaches by Nos 4 and 3 Commandos, whose tasks were to neutralise enemy battery positions 6 miles to the east and west of Dieppe. At the same time a Regiment of the 2nd Canadian Corps was to be landed to secure Green Beach three miles to the west of Dieppe, and to attack objectives on the west outer perimeter of the town (Hindenburg). Simultaneously the Royal Regiment of Canada was to secure Blue Beach 1½ miles to the east of Dieppe, and objectives on the east flank of the outer perimeter, ie; Bismarck. Half an hour later the Royal Hamilton Light Infantry and Essex Scottish Regiment with the Camerons of Canada were to make a frontal assault on Red and White Beaches in front of the town of Dieppe. This frontal assault was to have been supported by an armoured detachment of tanks. Later a Royal Marine Commando was to land near the harbour of Dieppe to demolish objectives in the dock area. A further echelon of tanks was then to be landed making a total of 28 tanks. It was intended, when the tasks ashore had been completed to withdraw the whole force for re-embarkation at about 1100 hours.
Air Support
5.Air support was to be provided throughout the operation as follows:-
Fighter Cover
| (i) | Fighter cover and general protection for the expedition throughout the hours of daylight. The primary task of this cover was to protect the expedition against air attack. It was considered that the two most dangerous periods in regard to attack from the air would be the landing and withdrawal. It was, therefore, decided that the strength of this fighter cover should vary from 2 to 6 Squadrons during the different phases of the operation, with such reinforcements as might prove necessary. |
Close support
| (ii) | (a) | Close support, bombing and low flying fighter attacks on selected targets were to be made in direct support of the assault, occupation and withdrawal. |
| (b) | Smoke laying aircraft were to be used to neutralise defences, both in accordance with the pre-arranged plan and subsequently as required at the request of the Military Force Commander. | |
| (c) | Day Bomber Squadrons were to be employed to attack both pre-arranged targets and requested targets. |
Reconnaissance
Strategical Bombing
| (iv) | It had been agreed between the three Force Commanders not to lay on any preliminary or diversionary effort with bombers prior to the assault in order not to jeopardise surprise. A strategical bombing attack was, however, planned against the enemy aerodrome of Abbeville, with a view to interfering with the operation of his defending fighters. This attack was to coincide with the main withdrawal from the beaches at which time considerable interference was anticipated from fighters operating from the Abbeville area. |
Disposition of the air forces in No 11 Group
6. The following forces were available:-
| Day Fighter forces | — | 50 Squadrons Cover |
| 6 Squadrons Close support | ||
| Day Bomber forces | — | 2 Squadrons |
| Hurricane Bombers | — | 2 Squadrons |
| Army Co-operation | — | 4 Squadrons |
| 'Smoke' forces | — | 3 Squadrons |
7. The assembly of these forces involved internal moves of Squadrons within No 11 Group and the reinforcement of the Group by 15 Squadrons from outside. These extensive movements were carried out on 14 and 15 August.
Detail of the squadron and necessary maintenance unit moves were as follows:
8. The following supplies of ammunition and petrol were ac- cumulated at stations in No 11 Group immediately prior to the operation:
| Ammunition | 20mm | 20mm | .303 | .303 | 20mm |
| Ball | HE/1 | AP | Incend | Links | |
| 727,200 | 727,200 | 7,484,400 | 2,474,800 | 1,454,400 | |
| Petrol | 100 Octane | Galls. | 712,000. |
Enemy Dispositions
9. The German Air Force had approximately 260 front line single engined aircraft between Brest and Texel. These were disposed as follows:—
| Holland | 40 |
| Pas de Calais | 125 |
| Brest to Fecamp | 95 |
10.The German policy since June this year has been to concentrate these air forces on a few aerodromes along the Western Front. The German system of reinforcement in flexible up to a point, with extreme mobility of units from one place to another. On the other hand he finds difficulty in adapting his control areas quickly to these reinforcements.
11.Apart from reconnaissance units and a small number of aircraft used for anti-shipping, the whole of the German bomber force on the Western Front has been in use by night only. This force was disposed in the Dutch bases at Eindhoven, Soesterberg, Gilze Rijen and Deelen. It numbered some 120 long range bombers with a further 100 at Beauvais, Creil, Chateaudun, Chartres and Rennes. Reports from pilots during the operation Jubilee indicate that a small number of bombers from reserve training units were brought into action. It was considered unlikely that he would be able to bring his fighters from as far west as Brest or as far north as Holland early in the operation. Thus the fighter forces likely to oppose us in the early stages were from the Abbeville area — 50, Beaumont - Le-Royer area — 50, Cherbourg area - 20, together with possible reinforcements from St Omer and Courtrai — approximately 30 and 45 respectively.
Command
12.Captain J. H. Hallett RNwas the Naval Force Commander. Major General F. N. Roberts MCwas the Military Force Com- mander
Air Marshal T. L. Leigh-Mallory CB DSOAir Officer Commanding No 11 Group, was the Air Force Commander
Operational Control
13.Control of all air forces was exercised direct by the Air Force Commander from his operational headquarters at Uxbridge. Air-craft were despatched on instructions issued from No 11 Group Operations Room through the normal Group to Sector, Sector to Squadron Dispersal point channels. The Force Commanders afloat were able to ask at any time for special air support from bombers or fighters by means of the W/T link provided between Portsmouth and the Headquarters Ship, and a listening watch maintained at No 11 Group Headquarters.
14.The lowest squadron in the fighter cover operated on No 11 Group Guard No 1 frequency so that the fighter controller in either of the headquarters ships could communicate with the squadrons of the fighter cover.
15.All outgoing close support fighter sorties called the Headquarters Ship by VHF R/T when approaching the enemy coast. The Fighter Controller in the Headquarters Ship then, at the request of either the military or naval Commanders, re-directed fighter sorties to attack any suitable alternative targets which the situation demanded.
16.Despite the fact that a very large number of squadrons were being used throughout the operation (over 60 Squadrons) this method of control worked admirably. During the whole course of this very gruelling test of the normal ground control organisation in No 11 Group there was no breakdown.
17.This proved conclusively that the existing fighter ground control organisation, although primarily designed for defensive pur-poses, provides all the facilities required for the direction of offensive operations within normal fighter range. The co-ordination of the Air Force effort from a central point is essential. The Group Operations Room with its extensive network of communications augmented by advanced W/T and R/T communication with local Commanders in the expedition proved to be ideal.
18.The local control by the Headquarters Ships proved equally successful. The bottom Squadron of all Fighter cover formations operated on No 11 Group Guard 1 frequency and were directed on to enemy aircraft by a Controller in Headquarters Ship No 2. Close support Squadrons operated on a Tangmere Sector Operational frequency and were directed on to targets as required by the Military Commander by a Controller in Headquarters Ship No 1. Thus the two Headquarters Ships accompanying the expedition were used to assist in the control of air forces as would an AASC during a land battle.
19.In the majority of cases Close Support Fighter Pilots had been briefed as to the targets to be attacked, before leaving the ground, but experience gained during the operation showed conclusively that it was possible to redirect fighters or to give them assistance in finding their target by local direction. Similary, fighters were frequently assisted in sighting enemy aircraft by the running commen-tary given by the controller in Headquarters Ship No 2. There is no doubt that this local control was largely responsible for the high percentage of interceptions made on enemy aircraft, thus greatly minimising the effectiveness of enemy air attacks on ships and troops.
20.To summarise — the system of control from the Group through Sectors, and through the Headquarters Ships, adequately met all requirements. The excellent communications and flexible control facilities of the normal Fighter organisation at home proved most efficient for such combined operations.
Tactical Reconnaissance
21.Tactical reconnaissance units suffered a higher casualty rate than any other type. This was due to the deep penetration required of them which necessitated their patrolling well beyond the area of fighter cover. The coast roads leading to Dieppe were reconnoitred every half hour, and those from Amiens, Rouen, Yvetot, and Le Havre, places from which reinforcements might be expected, every hour.
22.Aircraft took off from Gatwick, flew to the Dieppe area via the Beachy Head route, made contact with the command ship, and then proceeded on their allotted tasks. On completion of each sortie tactical reconnaissance pilots flew sufficiently near to the ship to ensure satisfactory R/T transmission of any information they had. They then returned immediately to Gatwick and passed their information by telephone to the Air Force Commander.
23.The only movement worthy of note was that of about five light tanks approaching Dieppe reported at 1210 hours.
24.The range of the HF fitted in the tactical reconnaissance aircraft proved inadequate.
ASV Reconnaissance Patrols
25.Aircraft of Coastal Command maintained ASV search patrols throughout the hours of darkness on the flanks of the expedition during the passage. No sightings were made.
General Narrative
26.The operation is conveniently divided into five distinct phases. The first covers the outward passage and the landings on various beaches. The second covers the period when progress was being made towards the predetermined objectives ashore. The third phase covers the withdrawal of landing parties to their beaches.The fourth period extends to the time when the withdrawal was complete. The fifth phase covers the return passage to England.
27.The expedition sailed from the area of Portsmouth Command in a succession of Groups on the evening of 18 August, headed by the destroyer Calpe.
28.Shortly before dark the convoy which consisted of 217 craft in all, steamed past the Calpe (Headquarters Ship No 1) to be checked.
29.In the early hours of the 19 August, the Calpe led the way through an enemy minefield, which had already been swept by a flotilla of minesweepers from Newhaven. A quarter of an hour later the whole convoy was safely through the minefield but it was noticed that the LCTs had lagged some way behind.
30.Shortly after 0300 hours the first landing craft were lowered from their parent ships. The lighthouse on the cliff outside Dieppe was then visible. Up to this time the outward passage was comparatively uneventful, but a misfortune now occurred.
31.The landing craft conveying No 3 Commando, which had been detailed to attack Yellow Beach (6 miles east of Dieppe) came into contact with an enemy convoy which included armed trawlers, and a number of our small craft were sunk. These losses resulted in the failure to subdue coast defence batteries to the east of Dieppe.
32.There was no other enemy activity throughout the night and no attempt was made by the enemy to reconnoitre for our approaching expedition. It would seem, therefore, that the force was assembled and dispatched without disclosure. It would have achieved complete tactical surprise if No 3 Commando had not unfortunately been intercepted by the enemy trawlers en route.
Narrative Phase 1 0445 - 0550
33.Despite the chance contact with enemy ships en route, the forces arrived at Dieppe approximately on time, and the initial naval bombardment of selected objectives was carried out as arranged.
34.In the opening attack, escort was provided for smoke carrying aircraft of bomber and Army Co-operation Commands laying a smoke screen over the cliff headland to the east of Dieppe Harbour. This was most effective lasting from 0510 to 0600 hours. Intruder aircraft engaged each of the two gun batteries to the south of Dieppe with bombs and machine guns. Hurricane Bombers, Fighters and Spitfires attacked the coastal emplacements, and beach defences. Cannon fighters provided direct support to our troops as they landed at Red and White Beaches in front of Dieppe and were successful in centralising enemy fire along the front from 0515 to 0525. During the landings there was little opposition from enemy aircraft.
35.In phase 1 our surface forces kept to their time table despite shelling by enemy shore batteries. Batteries situated to the south of the town were slow to commence firing but when they did were particularly destructive. Further smoke screens were requested to cover our landings, a necessity which had already been anticipated and additional smoke aircraft were already on their way to the scene of action.
Phase 2 0550 - 0730
36.By the second phase landings had been effected successfully on Yellow (East Commando) Green (West flank) and Orange (West Commando) Beaches and progress had been made towards the surrounding houses.
37.The Western Commando had been completely successful in overcoming the battery position at Hess and killing all the person-nel. The final assault on this position was assisted by a squadron of Spitfires which attacked Hess battery at 0620 just before our men were due to attack. This assistance was successful and the attack was made immediately our Spitfires had finished. The OP of this battery was in a lighthouse close by which had been attacked by two Spitfires at first light. The landing on the beach IV2 miles to the west of Dieppe (Green Beach) was also successful, capturing the RDF station and destroying their other objectives.
38.The eastern flank (Blue Beach) initial attack had, however, failed. A second attack made at approximately 0740 resulted in a small penetration which, however, did not succeed in silencing the guns on the Eastern Headland. In the main landing on Red and White Beaches the tanks were held up by the inability of the engineers to land the explosives necessary to blast a passage through the promenade wall, with the result that the majority of the tanks were stranded, and the infantry were disembarked whilst the tanks were still immobilised. Large white houses overlooking the beaches gave considerable trouble and bombardment by destroyers was requested from our troops ashore.
39.In view of these difficulties a further smoke screen was called for on the eastern headland Bismarck but no aircraft were immediately available for this. The smoke carrying aircraft were at once ordered to load up with smoke and take off as soon as they were ready.
40.Earlier attacks had failed to silence the eastern headland defences and the gun positions (Hitler and Goring) south of Dieppe continued to shell the beaches.
41.Twelve Bostons had already been ordered off to bomb Hitler and were quickly airborne.
42.Rommel was also still giving trouble and the landing on Blue Beach had in consequence failed. The only remaining Bostons were, therefore, detailed to attack Rommel followed by a further six when they became available. All these batteries continued to harass our troops and an attack was called for on Bismarck. A squadron of Cannon Hurricanes had already been despatched to be 'on call' to the headquarters ship by 0740 and a second squadron of Cannon Hurricanes was despatched to be 'on call' to the headquarters ship 20 minutes later.
43.Thus at the end of the second phase the RDF Station, 5 light AA positions had been captured and the gun battery behind the Orange Beach had been demolished. Throughout this period air cover was afforded to the troops against moderate enemy fighter opposition; the number of enemy aircraft patrolling the area at any one time during this period did not exceed one Squadron.
Phase 3 0730 - 1050
This third phase covers the withdrawal to the beaches.
45.At 0752 two Cannon Hurricane Squadrons were ordered to engage enemy E-Boats which had been reported proceeding south from Boulogne. Two fighter cover squadrons accompanied these Hurricanes. At the same time a message was received cancelling the support on Bismarck and Rommel. The Air Force Commander was always doubtful whether this latter message was genuine, but had to act on it as information was received within a few minutes that a second landing on Blue Beach had been successful. At this time one Bomber Squadron was also on its way to bomb Rommel and was beyond range of recall. Aircraft were also on their way to drop smoke bombs on the eastern headland; these were recalled.
46.The situation had meanwhile deteriorated on the western flank. Heavy opposition was also coming from the western headland and the houses behind the beach. Machine gunning and shelling continued undiminished from the headland and from Hinden-burg.
47.A squadron of Hurricane Bombers and a squadron of Cannon Fighters covered by two Spitfire Squadrons were ordered to attack these positions.
48.The situation in various areas continued to grow critical and due to various delays the time scheduled for the evacuation was deferred from 1030 hours to 1100 hours.
49.At 0956 the following reply was received to the Air Force Commander's request for a situation report: 'Situation too obscure to give useful report. Air co-operation faultless. Enemy air opposition now increasing. Have you any questions.'
50.A few minutes later a request was received for a 30 minute smoke screen along Red and White Beaches from 1100 to 1130 hours: Thruxton was ordered to prepare as many aircraft as possible with SCI and as many aircraft as could be fitted were ordered off for this purpose. The Military Commander gave Green Beach third priority after Red and White Beaches for smoke and 3 Blenheims with an escort squadron were detailed to this task.
51.At 1039 a request was made for maximum fighter support against machine gun positions on both headlands.
52.Four close support squadrons were ordered to these attacks with two squadrons as cover.
53.A further call for support against the headland came in 20 minutes later, by which time squadrons were already on their way. At this time it appeared that the LCAs were arriving at White Beach, ready to re-embark the forces on shore. Thus at the beginning of this third phase the right wing of our landing forces had made progress but those in the centre including the tanks were held up
54.Enemy air opposition had by now increased considerably, 20 to 30 fighters being seen continuously in the area until 1000 hours when enemy bombers appeared escorted by fighters.
55.The enemy employed a considerable number of bombers from aerodromes in Holland in addition to small numbers from Beauvais. To counter this increased enemy activity and in order to cover re-embarkation, which was about to commence, the strength of fighter cover over Dieppe was increased from 3 to 6 Squadrons. Heavy casualties were inflicted on the enemy bombers who were now concentrating on shipping and landing craft.
Phase 4 1050 - 1410
56.The fourth phase marks the withdrawal from the beaches. During this time the gun batteries Bismarck and Hindenburg on the east and west headlands continued their intense bombardment, and in many areas the situation was more than critical.
57.Until the expedition had safely withdrawn, frequent and urgent requests were received for bombing and close support attacks on enemy gun positions, and calls for smoke screens were made.
58.At 1030 hours a most successful pre-arranged attack was made by 24 Fortress Bombers escorted by four Spitfire IX Squadrons, on the enemy fighter aerodrome at Abbeville-Drucat. Some twenty-five tons of high explosives and a large number of incendiaries were dropped. Many bursts were seen in the north-west dispersal areas and on the runways whilst fires were started in woods adjoining the dispersal areas. Bursts were also observed on storage sites and clouds of black smoke were seen rising from the whole target area. This very accurate bombing of dispersal area and runways - bombs fell near to at least 16 aircraft in these areas - caused considerable confusion to the enemy, and he was denied the use of his aerodrome for probably 2 hours, his aircraft being instructed to land at alternatives. The Abbeville control was out of action until the evening, when a new and unfamiliar voice came on the air.
59.This attack on Abbeville was followed by a diversionary feint made towards Ostend by a Typhoon Wing in an endeavour to draw enemy air forces away from Dieppe.
60.The enemy air activity by this time had increased and he had altered his form of attack. The tactics of our fighter cover were changed to meet this situation by adding a high squadron of Spitfire IXs at 23,000 feet.
61.During this period bombing attacks were made by Boston Squadrons on Bismarck and Hindenburg.
62.Further attacks were also made by three close support squadrons and smoke was laid between the east and west headlands across the port of Dieppe to cover the final withdrawal.
63.The constant requests for bombing, close support and smoke were met to the limit, demands frequently being anticipated as a result of the clear picture available in the Fighter Control Room at Uxbridge. All types of squadrons were called on to operate a shuttle service.
64.It was decided that tactical reconnaissance aircraft could serve no further useful purpose and their operational flights were discontinued.
65.In the final withdrawal a maximum effort was directed to protect our re-embarking forces from both ground and air attack.
66.By 1310 it appeared doubtful whether any more troops could be evacuated. An hour later the last craft was reported 3 miles from the French coast. The withdrawal from Dieppe had been completed.
Phase 5 1410 - 2245 hours
67.As our forces cleared the enemy coast smoke-laying aircraft laid a protective screen between them and the enemy's defences.
68.The Typhoon Wing was then reinforcing our Spitfires in intercepting enemy bombers coming from the direction of Holland.
69.Fighter Cover was maintained throughout the long voyage home.
70.There was considerable deterioration in the weather and the enemy took advantage of the increasing cloud cover to send out single bombers to attack our ships as they neared the English coast. One or two formations of FW190s were also employed for this purpose. In addition to standing cover over the returning convoy, 86 interception sorties were made.
Appreciation of the Enemy's Air Effort
71.The enemy reacted almost as had been foreseen; at first he did not appear to appreciate the scale of our effort and he used only 25/30 fighters in each sortie. As the day went on the strength of his sorties increased to between 50/100 aircraft. At first fighter bom-bers, and later, when the moves from Holland had been effected, night bombers in increasing numbers were used until all his resources on the Western Front were in action.
72.Early in the day enemy air effort was confined entirely to fighters patrolling the area in small numbers. Occasionally dive attacks on our ships were made from height. The German control merely instructed his aircraft to go to the Dieppe area where large numbers of British bombers and fighters were operating.
73.It was not until about 1000 hours, some six hours after our assault, that our patrols encountered enemy bombers. It would seem, therefore, that these had not been at a high state of readiness.
74.The first bombers came in small numbers and were escorted by FW190s. Later larger formations up to 15 in number operated under the main German Fighter Force which was engaging our cover patrols. Reports from pilots indicate that a small number of reserve training bombers were included.
75.The German Bomber Force throughout confined its attentions to our convoy and did not harass our troops ashore. A bomber jettisoned its bombs and crippled HMS Berkeley shortly before 1300 hours. She was later sunk by our own forces. The attack on Abbeville-Drucat at 1030 hours was undoubtedly successful in striking at the enemy's most congested aerodrome at a critical period in the operation. This attack was timed and prearranged to this end and it undoubtedly succeeded in considerably reducing the efforts of the GAF against our expedition.
Casualties
76.(Details of casualties were noted in an appendix to this report -N.F.)
77.The very low rate of casualties suffered in all types of squadrons during such intensive day-light operations in close support of a combined operation are of particular interest.
Administration
78.The concentration and redisposition of Air Forces in No 11 Group was for security reasons undertaken as a reinforcing exercise, under the title of Venom.
79.No serious administrative difficulties were experienced throughout the operation, though the shortness of the period of activity did not perhaps bring to light some of the difficulties which might have arisen had it been more prolonged.
Communications
80.Communications on the whole were excellent. Signals were promptly and clearly received at Uxbridge. The majority of outgoing messages from Uxbridge to the headquarters ship retransmitted by Portsmouth, did not reach the Military Commander afloat, so that requests for close support from the ship were often repeated unnecessarily.
81.The control organisation in the ships worked very efficiently and this system is capable of further expansion and development.
82.Additional land line links to Uxbridge for the operation worked fairly satisfactorily, although some of the temporary lines were not up to the high standard necessary.
83.The operations and Intelligence Teleprinter Operators worked at high pressure but were able to handle the traffic without serious delays.
Conclusions
84.(i) This operation showed that such expeditions can be success-fully supported and protected by home defence fighters operated by the normal Home Defence Fighter Organisation, assisted by for-ward direction through R/T in ships. This efficient organisation is fully capable of so operating air forces to the limit of present fighter range and is bound to be superior to any alternative forward control scheme which could never provide anything like equal facilities.
(ii)Landings on such a scale in occupied territory in daylight effectively pin the enemy air forces to an area enabling our support-ing fighters to operate at height and in conditions best suited to them. In existing circumstances the enemy is forced to employ his night bombers in daylight, at times unescorted by fighters thus sacrificing an appreciable part of his limited bomber resources.
(iii)Close Support attacks by cannon fighters are effective only whilst they are engaging their targets, but they have no lasting material effect on well protected defensive positions. They are extravagant in as much as each aircraft is in action for a few sec- onds only. To achieve any lasting moral effect would demand such a large expenditure of these Fighters that our efforts in other direc- tions would be reduced to unacceptable proportions.
(iv)A very much higher standard of interservice recognition is essential in combined operations. As modern aircraft are all so alike, it is important that all personnel have a very thorough know- ledge of and frequent practice in recognition.
(v)Airborne smoke is extremely valuable in combined oper- ations. Smoke is often likely to have better effect than bombing, particularly if it is intended to protect surface forces against well placed gun positions. It is essential however, to speed up the pre- sent rate of turn round for smoke carrying aircraft and to be able quickly to alternate between SCI and bombs and to change over from one to the other on the ground in the shortest possible time.
(vi)Some difficulty was experienced at times in obtaining detailed target requirements from the Headquarters Ship. This problem of locating and selecting suitable targets for Air attacks, together with methods for defining, to the Air Force Commander requires careful interservice study so that the Air effort is always profitably employed.
Certain major conclusions together with my recommendations for awards are being forwarded by me in a separate letter.
T Leigh-Mallory
Air Marshal
Air Force Commander
(Public Record Officer File Air 25/204)