A short description and appreciation.
This features photos and images of the Roc I have found in old pre-war or wartime books, magazines and postcards. If any of these images are covered by copyright or are owned by picture libraries please let me know and I will remove them from the page straight away.
Thanks to Mark E Horan for details of the Rocs operational use from HMS Ark Royal, and to Peter C. Smith for the information on the Roc's only air-to-air victory.
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The Blackburn Roc was a development of the Skua Fighter/Dive Bomber, designed to meet specification 030/35 for a two seat fighter to operate off aircraft carriers. It was fitted with a rotating electric-pneumatic driven turret mounting four .303 Browning machine-guns. This "type A" turret was manufactured by Boulton Paul, being largely based on the French designed SAMM turret, for which Boulton Paul had secured a production licence. Boulton Paul already had experience of aircraft turret production having produced the enclosed pneumatic turrets for the front gunners position on the Bolton Paul Sidestrand bomber (the first turret used by the RAF) and the company had also been responsible for installing the partially-enclosed Fraser-Nash FN-1 "lobsterback" turrets into late production Hawker Demon two-seat fighters. The production of the Roc was undertaken for Blackburn by the Boulton-Paul factory on the outskirts of Wolverhampton. In all 136 Rocs were produced .The First production Roc serial number L3057 (there were no specially built prototypes) flew on 23rd December 1938. It must have been heart-breaking for Boulton Paul to be producing the Roc when their own turret armed design, the Defiant, the prototype of which had first flown a year and a half earlier, was 100 miles per hour faster! (Boulton-Paul had tendered their own design to 030/35, the P85 with either Merlin or Hercules engines). Defiant production was underway from July 1939 and Rocs and Defiants were produced in the same factory for a year, the last Roc not being delivered until August 1940. The Roc differed from the Skua in having dihedral on the wings, doing away with the Skua's upturned wing tips, this improved stability. It carried no wing guns. The Roc featured a hatch in the floor for the gunner to use. The gunner did not wear his parachute when manning the guns (unlike in the Defiant where a special slimline "parasuit" with built-in parachute was worn by the gunner) instead it was stowed on the side of the fuselage for the gunner to clip on before exiting through the floor hatch. The underside of the aft of the wings was flat, compared with the Skuas complex curved structure in this area. The Roc's propeller was of larger diameter than that used on the Skua to try to improve speed and climb. The Roc could be fitted with a "universal carrier" under each wing along with "light series carrier" bomb racks for light or practice bombs. The loads that each universal carrier could carry was listed in the pilots notes as either a 250 lb "B" or Semi-Armour Piercing (S.A.P.) bomb or a 100 lb Anti-submarine (A.S.) bomb or a bomb container. It was cleared for dive-bombing up to angles of 70 degrees. Its role was seen as that of a fighter but the extra weight of the turret made it even slower than the Skua and it could not catch anything but the slowest of German sea planes (amazingly the only confirmed victory by a Roc was the shooting down of a Ju 88, the fastest of the German bombers).
In internet articles, magazine articles and books the one phrase that is used again and again about the Roc is that it was designed to "deliver a broadside" to an enemy aircraft. The author then usually goes on to ridicule the concept and make disparaging comparisons with three-masted sailing ships. The Roc, assuming it could catch up with its prey, would be much more likely to approach from below and try to bring its target down with no-allowance shooting; firing ahead and over the top of the pilot. The tactic of no-allowance shooting was very much at the heart of the philosophy behind the Roc and Defiant and yet it is hardly ever mentioned in descriptions of both aircraft, and the few articles available today on this subject only serve to obfuscate the principles behind it.
Click here to read about no-allowance shooting
The thinking behind the Roc's design was heavily influenced by the Royal Navy's belief that the fleet at sea would be able to defend itself from air attack by anti-aircraft (AA) fire. The Navy invested considerable amounts in this policy; building and converting a whole range of "anti-aircraft cruisers" that were designed to put up an impenetrable barrage of AA. For example each of the Dido class anti-aircraft cruisers mounted ten 5.25 inch anti-aircraft guns in five turrets for high and medium defence (more AA guns than many British cities had to defend them in 1939). For low-altitude defence each Dido carried eight 2pdr "pom-pom" guns in two quadruple mounts and eight large-calibre .5 inch machine guns in two quadruple mounts. Battleships and aircraft carriers even had eight 2pdr pom-poms in single mountings! Anyone seeing an eight barrelled pom-pom firing would be easily convinced that no aircraft within range could possibly survive.* It was considered that defending fighters would simply get in the way of the AA barrage, and that to turn an aircraft carrier into wind and steer a straight course to launch fighters when enemy bombers were attacking would make the carrier extremely vulnerable. Of course a "fleet shadowing" aircraft could stay outside the range of the AA barrage and radio back the fleet's position to the enemy, and it was to ward off this kind of aircraft that the Roc was designed (and indeed it was for that purpose they were used off Norway in 1940). You could regard it as a kind of flying machine gun post, flying around the fleet to extend the range of the AA barrage and ward off, approaching enemy aircraft. A fleet shadowing aircraft would hope to avoid contact with opposing fighters by hiding in cloud cover, popping out every so often to keep contact with the ships it was shadowing. You can see that a traditional fighter with forward firing guns might find it difficult to cope with this strategy if there is plenty of cloud cover to hide in. A turret armed fighter has two pairs of eyes to search for the shadower and spot it as it pops in and out of the clouds, and the turret can be turned quickly to engage the target before it disappears again. Against such targets - fleet shadowing aircraft such as the Japanese Kawanishi E7K, Italian Meridionali Ro 43 or German Heinkel He60 the Roc might have been a potent adversary, but in 1939/40 such designs were being superseded by faster and heavier armed aircraft such as the Arado Ar 196 and Aichi E13A which could outrun and outgun the Roc. No sooner had the Roc been ordered than experiments with shipborne RDF (radar) held out the promise of being able to detect incoming enemy aircraft and launch fighters in time to intercept them. So the Sea Gladiator was quickly ordered into production. It was the advent of radar that changed the whole concept of air defence of the fleet.
The Royal Navy also saw the Roc as an escort fighter to accompany torpedo bomber strikes against an enemy fleet, staying alongside the torpedo bombers as they went in for the attack. Such a scheme may seem laughable, but I wonder if the Swordfish crews that threw themselves against the Sharnhorst and Gneisenau in the "Channel Dash" might have appreciated an escort of Rocs to keep the Fw190s away for a couple of vital minutes. For that matter what about the Devastators and Avengers at Midway? Would an escort of a few turret fighters have kept the Zeros away for long enough for at least a few torpedoes to find their mark? Or would it merely have added to the slaughter?
All Roc production took place at Boulton Paul's factory at Pendeford, then a factory and airfield complex on the outskirts of Wolverhampton (the airfield is now built over and Pendeford is now a suburb of Wolverhampton). The Rocs were ordered in one batch of 136 aircraft allocated serial numbers L3057 to L3192. The first Roc flew on 23rd December 1938, but it was not until March 1939 that Rocs began to trickle off the production line and it was not until July 1939 that production seemed to a have settled down to a steady flow. The last Roc off the production line was delivered in August 1940.
Early production Roc L3059, The Roc was a large aircraft, look how small the pilot looks in the cockpit. The two lines behind the landing light on the wing are two small strakes, a permanent feature on both the Roc and Skua, it was to these that the light bomb carriers were attached when needed.
The Roc was designed to be fitted with a pair of floats of the same design as used by the earlier Blackburn Shark biplane. In August 1938 , 4 months before the Roc first flew, it was already apparent that the Roc's lack of speed would make it a poor fighter. At a conference to discuss the situation the Director of Air Material had suggested that Roc Floatplanes be allocated to the large capital ships of the Royal Navy, with no less than 3 Rocs apiece for Malaya, Warspite, Repulse, Renown, Queen Elizabeth and Valiant and a single Roc for Rodney.** This suggests that the Roc would have been used primarily as a spotter to replace the Fairey Seafox and Supermarine Walrus. Five Rocs in the UK are known to have been modified with floats (there is only direct photographic evidence for four). It was found that the flying qualities of the first Roc with floats fitted (L3059) was poor (it was lost in a crash), but the fitting of a large dorsal fin under the tail improved the stability of the four other Roc floatplane modifications that are known to have followed in the UK (L3057, L3060, L3143 and L3174). The last of these operated with the turret removed and a target winch fitted. Research by Thomas Singfield and Ewan Partridge shows that some of the 5 Rocs operated by 773 FRU based on the island of Bermuda may have operated on "home-built" floats. L3069 the first Roc to arrive in Bermuda was certainly fitted with floats. Read Thomas Singfield and Ewan Partridges book on the history of aviation in Bermuda "Wings over Bermuda" published by the National Museum of Bermuda Press and available in the UK from the Aviation Bookshop in Tunbridge Wells.
L3057, the first Roc floatplane conversion.
This picture shows the large ventral tail fin used on subsequent conversions.
Roc floatplane L3143 is rolled out of a hanger. The sheer size of the Roc is evident in this picture . Notice the undercarriage recess has been covered over but not painted. The enlarged ventral tail fin can be seen.
A single Roc (L3089) was modified with a special lightweight turret to take a cine camera for air-to-air filming. Presumably there was some reason for this but it is not known if this installation was ever put to use.
There is some controversy about the range of the Roc. Many books and on-line guides quote a figure of 810 miles, but this is simply an impossible figure for the standard Roc. The Skua had a range of some 760 miles, this was provided by fuel tanks with a combined capacity of 163 imperial gallons, this was made up of a 39 gallon tank in front of the cockpit and two side-by side tanks of 62 gallons each between the pilot and gunner position. The Roc carried only 117 gallons of fuel, this was provided by the same 39 gallon tank as the Skua in front of the cockpit but only a single, albeit slightly larger, tank of 78 gallons behind the pilot.. The extra space between the pilot and gunner was largely taken up by the radio equipment which had to be placed here to keep the balance of the aircraft within acceptable levels (on the Skua the radio equipment was carried just aft of the gunners position). There was just enough room to allow the gunner to use the escape hatch in the floor of the fuselage. So it is impossible to see how the standard Roc could have had a longer range than the Skua while carrying considerably less fuel and also weighing more and having the extra drag of the turret. it would seem unlikely that a standard Roc would have a range greater than 550 miles. However, a bulged "belly tank" of some 70 gallons capacity was fitted to at least one Roc and it would seem likely that it was the fitting of this that gave rise to the often-quoted figure of 810 miles range. However, this belly tank was by no means a standard fitment and it is not mentioned at all in the Roc pilot's notes. It seems likely this belly tank was only produced in prototype form following complaints about endurance from the squadrons using the Roc for defensive patrols around the naval base at Scapa Flow (see combat history below).
Above is a photo of the single Roc fitted with the "pregnant" belly bulge to accommodate an extra fuel tank to boost range.
Made Ready for Finland
In early 1940 it was decided to give a large part of the production run (33 aircraft) to the Finns, at the time fighting the Russians. Preparations went as far as painting the aircraft ready for delivery and collecting them together in Scotland for the flight. The end of the Finnish "Winter War" stopped delivery. The Finns had a reputation for getting the most out of the assorted aircraft they operated and it would have been interesting to see what use they would have made of the Rocs had they arrived. One suspects they would have been better used as dive bombers rather than fighters. By all accounts, the Roc's performance as a dive bomber was good, and if it made its getaway flying just above the ground or sea it was a difficult target for enemy fighters to engage, and in such a fight there was at least a chance that it its four belt-fed turret guns could bring down a pursuing enemy fighter.
Blackburn Roc Specification
Two seat naval turret fighter
Engine: One 815 hp Bristol Perseus XII engine (gave 900 hp plus for short bursts)
Max speed 223 mph (with engine on emergency power), Cruising speed 135 mph.
Range and Endurance: - The subject of controversy; see main text.
Armament: four 0.303 Browning machine guns with 600 rounds per gun housed in electrically operated turret. Two 250 lb "B" or "SAP" bomb or 100 lb anti-submarine bomb could be carried (one beneath each wing) and a standard RAF light series carrier bomb rack could also be fitted beneath each wing. Each carrier could hold 4 x 20 lb or 2 x 40 lb bombs or incendiaries. Thus the potential total bomb load of the Roc was 660 Ibs.
A factory-fresh Roc on a test flight. Note in the top picture the projections under the fuselage, these are the rearmost pair of four fittings for attaching the catapult launch trolley.
Service and Combat History
The Roc was first used operationally from October 1939 to help defend the naval base of Scapa Flow with 803 Squadron flying a mixture of Skuas and Rocs from the airfields at Wick and later Hatston. The presence of 803 did not stop a raid by Ju88s on 17th October which badly damaged the battleship Iron Duke. In response to this RAF Gladiators and Hurricanes were also deployed to protect Scapa Flow and they filled the short-range "interceptor" role while the Skuas and Rocs concentrated on longer-range patrols These missions involved long flights to cover the Home Fleet on its forays into the North Sea and to escort convoys and trawlers. It quickly became apparent that the shorter range of the Roc was a disadvantage compared with the Skua; the Commanding Officer of 803 requested that his Rocs be replaced by Skuas, but the request was refused and the Rocs remained on strength. As the severe winter of 1939/40 turned to spring the Luftwaffe once more turned its attention to Scapa Flow and it became the centre of world attention when a series of air raids on the base in March and April signalled the end of the "phoney war". By this time Scapa's defences had been improved with radar warning and very effective anti-aircraft barrage, and although the Germans used their fastest, most potent bomber; the Ju88, the raids achieved little. During one of these raids a Roc from 803 claimed to have damaged a German bomber.
Nice view of a Roc with type "A" roundels on both the wings and fuselage. Notice the line where the tail assembly joins the fuselage. The production of the tail assemblies of both the Skua and Roc were sub-contracted to the General Aircraft Company and brought in as complete units.
After the German Invasion of Norway Ark Royal hurried back from the Mediterranean. On 23rd April 1940 800 and 803 squadrons took 2 and 3 Rocs with them respectively when they sailed to Norwegian waters aboard the Ark Royal, (there was reportedly also a single Roc on board HMS Glorious). The three Rocs of 803 squadron were launched twice on 28th April when they drove off German aircraft shadowing the British carrier force (see Skuas over Norway). This was exactly the role originally envisaged for the Roc. The Fleet Air Arm's 805 Squadron was formed at Donibristle in Scotland in early May 1940 with the intention that it it should become an all-Roc squadron to operate in the floatplane role against the Germans in Norway. The Squadron completed initial training on the landplane Roc and then moved south to Lee-on-Solent to await delivery of the floatplane conversions. This plan was quickly scrapped and the squadron was disbanded only a few weeks later.
The next combats for Rocs came over Dunkirk, where 801 and 806 squadrons both operated a mixture of Skuas and Rocs. The only confirmed "kill" by a Roc took place about 6.30pm on 29th May 1940 when a Roc of 806 squadron piloted by Midshipman Day, RNVR with his gunner Naval Airman Newton claimed one Ju88 destroyed (it was seen to crash into the sea) and another damaged in an action in defence of a British evacuation shipping. 801 Squadron used its Rocs for dive bombing attacks on German E-boats in Boulogne harbour on 12th and 13th June 1940*** and on gun positions on Cap Griz Nez on 21st June, loosing a single Roc on the last attack (For fuller details of these actions click on this link... Dunkirk).
The Battle of Britain and after...
During the Battle of Britain period the units operating Rocs near the south Coast of England found themselves in the front line. This included 2AACU (Anti Aircraft Co-operation Unit) based at Gosport near Portsmouth, various Naval flights operating out of nearby Lee-on Solent and 559 fighter training squadron at Eastleigh (now Southampton airport). On the 13th June a Roc from 2AACU exchanged fire with an enemy aircraft . On the 12th August 1940 a Navy Roc operating from Lee-on-Solent was surprised by a Bf109 on his tail but managed to escape by going into a steep dive and using the dive-brakes to pull-out low over the water. On the 16th August Gosport airfield was attacked by Stuka dive-bombers and two Rocs were damaged. On the 18th August Gosport was raided again with extensive damage caused. This prompted the stationing of 4 Rocs around the perimeter of the airbase, with the rear fuselage propped up and their turrets permanently manned during daylight hours to operate in the ground-to-air role.**** The most well documented Roc encounter with an enemy aircraft came on the 26th September when a Heinkel 59 Seaplane was engaged over the Solent, an event fully described by Sqdn Ldr DH Clarke in the article "The Decision is Always the Pilots" in the October 1961 edition of the RAF Flying Review.
There are suggestions that during the winter of 1940-41 Rocs were sometimes used in Scotland and the north of England as night-fighters against German bombers and mine-laying aircraft. Certainly Rocs operating out of Donibristle kept an eye out for German raiders when conducting training missions over the Firth of Forth.
After 1940 Rocs were mainly used for training, most being converted to target-towing. They found their way to the Mediterranean, Egypt, South Africa and Bermuda. The last operational Rocs were withdrawn through lack of spare parts in 1943.
The use of the Roc in combat is covered well in the book Blackburn Skua and Roc by Matthew Willis It includes some enlightening comments on what it was actually like to use the turret by ex-TAG Ken Sims.
This interesting picture above shows a formation of Rocs. Note the wide difference in the type of fuselage and wing roundels. Also note that the second aircraft has a reflector gunsight and there is a gun camera mounted near the wing root. All the aircraft carry bomb racks. It seems to have been common for the front sliding portion of the cockpit to be removed altogether (as in the 4th aircraft and the photo below). The fairing aft of the turret and the section of cockpit "greenhouse" between the pilot and turret were raised and lowered automatically to allow the turret to be rotated without obstruction, hence the difference in profile between the aircraft. The wireless aerial also "bent" with the retracting greenhouse section.
A Great picture of a pair of Rocs (same aircraft as in the close-up shot further up the page). It is taken from a wartime postcard that was produced by photographic methods. With a magnifying glass on the original you can see that the front engine panels were held in place by pins with very large "O" rings on the end, like big keyrings, so much for streamlining! The Roc was a very large aircraft, note how small the pilot looks in his cockpit. You can see the "light series" bomb rack beneath the wing and the larger rack for a 250 lb bomb inboard of it.
The picture above is not of a Roc, but of the stub wings on the wheels of a Westland Lysander, however it does show up close exactly the same type of bomb racks used on the Roc. On the right is the Light Series Carrier, able to take four 20 lb or two 40 lb bombs, this bombrack was also used on Skuas. On the left is the 250 lb rack, in this case holding a supply container.
Head on view of a Roc without the front spinner on the propeller. This picture clearly shows the two small sections of undercarriage door which flipped out at right angles to the airflow when the undercarriage was extended. It also shows well the "flat bottom" of the Roc, you can just make out the hatch in the bottom of the aircraft for the gunner to exit. The half black / half white colour scheme was that adopted at the start of the war to try to make friendly fighters more easily identified by the Observer Corps through binoculars at height.
Rocs on Carriers
The dustjacket of this wartime boys adventure story shows a Roc over an aircraft carrier. Many books on World War II aviation that mention the Roc, even Putnam's " Blackburn Aircraft since 1909", state that the Roc never made any carrier flights at all, they most certainly did, and not just training flights either (see combat history above), this is confirmed in the combat reports of the squadron's involved. A photo of Roc (L3062) of 803 Squadron operating from HMS Ark Royal is featured on page 57 of Stuart Lloyds book "Fleet Air Arm Camouflage and Markings". To prove that Roc trainers also operated from carriers another photo on page 72 of the same book shows a Roc target tug on HMS Formidable. The combat reports of the various Fleet Air Arm Squadrons that used Rocs on operations are available via the Public Record Office at Kew.
Suggested Alternative Roc Use
October 1938 a meeting of the Air Council had
that Roc production should go ahead while acknowledging that it was
be a good combat aircraft****. It was pointed out that the Roc could be
an advanced trainer by the RAF if needed. With hindsight it is sad that
very sensible suggestion was not carried out and the Rocs not handed
the RAF "en bloc". As trainers for gunners for the Defiant squadrons
the same type of turret fitted in Halifax, Ventura and Albermarle
have been very useful. It would have been ideal for use on short range
rescue duties by RAF Coastal Command, dropping smoke floats and sea
help rescue vessels locate downed pilots or maybe even dropping
dingys (whole squadrons of Defiants were used in this role, but not
it was, the Royal Navy's
Fleet could defend itself was flawed. The 2 pdr pom-pom and Vickers .50
guns were nowhere near as deadly as was hoped and the volume of fire
up was itself a problem since under sustained attack a ship could
out of AA ammunition. The 5.25 heavy AA gun was a formidable and deadly
weapon, but the fire-control systems used at the start of the war
proved unequal to the task of ensuring it hit its target. The Navy had
expected the main aerial threat to
slow torpedo bombers (the form of attack it itself favoured), and the
use of accurate dive-bombing (first experienced off Norway) caused a
reappraisal of strategy. Unfortunately when the Navy did experience the
scale use of torpedo bombers against itself it was by the Japanese who
their revolutionary "Long-Lance" torpedoes which could be launched
range of the AA barrage. It was the arrival of radar that transformed
nature of fleet defence by fighter aircraft, making it possible to
incoming bombers and launch high speed single-seat fighters as
*** Sources for the Dive bomb attack on Boulogne are "Fleet Air Arm -The Admiralty Account of Naval Air Operations" HMSO 1943 and Captain Tom Harrington's interview in "Dive Bombers In Action" by Peter C. Smith.
**** It is worth noting that that the Boulton-Paul Type A turret used in the Roc was used on some naval patrol boats for air defence. The turret was also used in an "anti-aircraft tank" prototype based on a Light Tank Mk V chassis built at the British Army's workshop at Lulworth (The Light AA Tank Mk I that went into production and served with the British Army in Britain and the Western Desert featured a similar turret but armed with four of the Army's standard Besa 7.92mm machine guns rather than .303 Brownings). So there is a certain precedence for the Roc's turret being used in the ground -to-air role. In fact a Defiant gunner (the Defiant used the same type A turret) managed to shoot down a Bf 109 during the Battle of Britain after the Defiant itself had crash landed and was stationary in a field! A ground-to-air engagement of a different sort!
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