Blackburn B-25 Roc


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Blackburn B-25 Roc

The Roc was a two-seat Fleet fighter/dive-bomber developed from the Skua but with a wider rear fuselage to accommodate a Boulton Paul power-driven turret with four Browning machine-guns. The entire production of 136 aircraft was subcontracted to Boulton Paul Ltd, Wolverhampton. The first aircraft flew on 23 December 1938. Four Rocs were also flown experimentally with float landing gears.

Rocs served briefly with Nos 801 and 806 Squadrons, FAA, in 1940. When broadsides by the four turret guns proved a failure, Rocs were relegated to second-line duties in the UK, Egypt and Bermuda. Many were painted with diagonal black and yellow stripes in 1940 as target-tugs. Others were used in 1941 for sea searches for survivors of sinking ships and aircraft in the English Channel.


Dive brakes allowed the Roc to make very stable dives and it was an accurate bomber, although its bomb load was small.

The heavy gun turret destabilized the Roc and added weight and drag, reducing speed and altitude performance. A larger propeller and other aerodynamic refinements did little to improve things.

The Roc's armament was concentrated in the electrically operated turret. The Skua had tour wing guns and one flexible rear-facing gun.

Blackburn B-25 Roc

 MODELB-25 "Roc"
 ENGINE1 x Bristol Perseus XII, 675kW
  Take-off weight3606 kg7950 lb
  Empty weight2778 kg6124 lb
  Wingspan14.02 m46 ft 0 in
  Length10.85 m36 ft 7 in
  Height3.68 m12 ft 1 in
  Wing area28.8 m2310.00 sq ft
  Max. speed359 km/h223 mph
  Cruise speed217 km/h135 mph
  Ceiling5485 m18000 ft
  Range1304 km810 miles
 ARMAMENT4 x 7.7mm machine-guns

Blackburn B-25 RocA three-view drawing (1278 x 916)

Trevor Webb, e-mail, 20.12.2013 13:32

The Perseus egines Roc 2 was preceded by prototypes with the Bristol Mercury designated Roc 1. All had wing racks capable of carrying eight 30 lb or 50 lb bombs. It is of note that all production Roc 2s were built by Boulton Paul not Blackburn. Four production aircraft were completed as floatplanes.


VinceReeves, 05.03.2013 22:19

Anyway, to the Roc. Although it was pretty useless as a fighter, it was nevertheless a very good dive-bomber, and was used successfully in this role during the Dunkirk evacuation period.

It wasn't a plane the FAA really needed, but it could do useful work when necessary.


VinceReeves, 05.03.2013 22:13

Lots of silly comments here. Pretty much all of the FAA's British designed planes of WWII were operational successes with impressive combat records. Not one of them can be judged to have "failed". This is despite the fact that they were generally low-priority and often improvised from landplanes. They aren't directly comparable with U.S. planes because they were designed to different operational profiles. They weren't intended to perform extended sweeps of the Pacific, for example.

The U.S. types offered better performance if you go by the numbers, but by the time the FAA adopted the Hellcat, Avenger and Corsair in 1944, most of its important war-work was done. Just look at the kill statistics for FAA Hellcats for example. Once the siege of Malta had been lifted, the FAA didn't really have a great deal of really useful work to do, except escorting Atlantic and Arctic convoys, which could be done with Swordfish and Martlets. The BPF presence in the Pacific was more of a hindrance to the Americans than a help.

Ultimately, if the FAA had spent the entire war armed only with Swordfish and Sea Hurricanes, the war wouldn't have lasted a day longer.


Ian, e-mail, 16.01.2013 14:30

I said the RN got all it's best aircraft from the U.S. i.e. Corsair, Hellcat, Avenger. What's all this talk of P51's & B25's etc. RTFC. Read the f**King comment.


Klaatu83, e-mail, 23.09.2012 19:00

The Roc was intended to be the carrier-based equivalent to the Boulton-Paul Defiant. Although, in those days, carrier-based aircraft seldom performed as well as their land-based equivalents, the Roc was even more inferior than most. The top speed is listed as 223 mph, which meant that it wouldn't even have been able to catch up with most of the bombers of it's day. Apart from that, the "turret fighter" concept itself was misconceived. I understand that many Rocs were relegated to being parked around Naval Air Stations, in order that their turrets could be utilized for ground-based anti-aircraft defense!

As to the remarks about British vs. American carrier aircraft of the period, I think even renowned British test-pilot Eric Brown acknowledged the Grumman Hellcat to be the best all-around carrier-based fighter, and the Grumman Avenger to be the best carrier-based bomber, of the war. The Fulmar was a war emergency improvisation, in that it was really a pre-war light bomber that had been hastily remodeled to serve as a carrier-based two-seat fighter. The Fulmar featured good armament and range, and had the advantage of being available when it was badly needed, but it lacked the performance to face enemy fighters. The Firefly, which was an excellent aircraft, fell into a rather unique category, being more of a carrier-based multi-role combat aircraft, and was not really comparable to the single-seat fighters of the day. While Seafire flew beautifully, it was too short on range and too fragile for carrier operations. The Albacore, that "Stringbag For Gentlemen", was a good airplane, but too slow, and really didn't offer much of an improvement over the earlier Swordfish. As for the Barracuda, I don't believe I ever heard or read a good thing said about it, except that, being a monoplane, it was regarded as a definite improvement over the Albacore.


Barry, 04.09.2012 12:40

Well "Naga" your patriotism is to be admired, but your logic does need a bit of honing. The Sworfish deserves it's honours for the shear strength and ability to take battle damage but most of all for the outstanding bravery of it's crews. The plane was obsolete at the start of World War II but because of what was said above it carried on because quite frankly there was nothing else at the time. Cleaning it up and making into an Albacore was not the answer although there was an element of crew comfort. All the other aeroplanes sponsored by the Admiralty during the war were quite simply appalling. The Seafire was a brilliant aeroplane in the air but was never designed for shipboard use and that frailty was too self evident.

Your comments about American aeroplanes are not well considered. The Mustang came into it's own when the British gave it the Merlin engine and the Americans then realised what a winner they had. It's long range and strength were of such use to both the USAAF and the RAF. The B25 Mitchell was quite simply an outstanding aeroplane still flying to this day and whilst we had no real use for the B17 this is not to say that it was a bad plane, it was just the Americans had a different approach to bombing.

At the end of the day the Admiralty had to wait to the jet age to get it's procurement right with the Sea Vixen, the quite simply brilliant Buccaneer, the Phantom and Sea Harrier.


Bill Osborn, e-mail, 21.09.2011 13:47

Marty, I have read and have no doubt that it is true ,that the reason for the adoption of .303 machine guns for nearly all early WW2 aircraft was that some idiot civil servant thought it would be a good way to use all the leftover .303 ammo from WW1.


Ian, e-mail, 13.09.2011 01:11

You forgot to mention the Sea Fury, now that was a carrierborne fighter par excellence. Just too late for WW2 but served with distinction during over Korea. Possibly the best piston engined fighter produced. Post war though the UK produced some real gems.


Marty, e-mail, 08.09.2011 21:56

Big part of Englands problems in the air was poor performing machine guns 7.7 cal Brownings compare to 12.7 cal American Brownings Like a lot of good men were lost due the weak guns on good aircraft


Naga, 08.09.2011 06:37

Mediocre enough that in 1953, almost ten years after first entering service, the Firefly was still in frontline service with the RAF and continued to fly with Canada for several year afterwards. The Barracuda's service was stellar, in its prescribed role as a dive bomber, no other aircraft to see actual combat in similar roles could perform as well at low or high speeds. Very few of its "best" aircraft actually came from America. While I agree that such designs like the Hudson and Ventura were useful in coastal roles, their successes were limited and next to nothing compared to similar operations taken by the Bristol Beaufighter or Beaufort. The RAF seldom used the B-17 in any role other than maritime reconnaissance becuase its performance was inferior to their own designs (and was much more expensive to maintain as equipment was primarily American and had to be shipped over the Atlantic). Boston and Douglas twin-engine bombers of a variety of models were only used for their numbers, as well as the North American B-25. Becuase most of their four-engine bomber forces were concentrated in England, the British did accept the B-24 although casualty rates in general (in both American and British /Canadian hands) were much higher than Enlgish bomber counterparts. They turned down the P-38 becuase escort fighters (the RAF's intended role for the fighter), were little needed in the black of night for their primary raids, and even then the island-grown Mosquito was much, much more capable, with better range, varying payloads and armaments, and most importantly, advanced air-to-air radar. They didn't need much evaluation to see the inferiority of the P-51 to the Spitfire, the aircraft, despite its many supporters, being less maneuverable and responsive than either the Spitfire or E-4 /D /later G-model Bf 109s and Fw 190s (a fact not publicized in America but mainly in Europe and Asia). It's really a joke when you say all the best aircraft came from the US, since the American's considered quantity to be best, not quality. Pacific fighters were slow and sluggish against Japanese fighters (their only advantage being superior armament, and self sealing fuel tanks). Considering most of thier air-to-air kills were primarily lightly defended bombers and attack aircraft, there is really nothing impressive about them. Your statements are understandable though, American propoganda is easily swallowed, although a website like this is supposed to help with that. Try reading aircraft specifications and histories from foreign authors. They tend to give a more honest account about the facts.


Ian, e-mail, 23.08.2011 16:00

Firefly & Fulmar though nice looking & personal favouirites of mine, they were mediocre by the standards of the day. The Albacore wasn't a step up from the Swordfish. As for the Barracuda, you must be kidding. All it's best aircraft came from the U.S. & didn't get well served by British designs until after WW2.


Naga, 08.08.2011 06:24

You ever hear of the Firefly, Albacore, Fulmar, or Barracuda?


Ian, e-mail, 22.04.2009 13:00

Another monstrosity that the Admiralty inflicted on its pilots. Was it their policies & specifications that brought such aircraft into service? With the exception of the Swordfish did the RN have any decent first rate homegrown aircraft. Even the Seafire was a bit fragile for the task.


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