I have to disagree in both mentioned reasons! Sorry! a) The Blackburn Roc Mk-I and Roc B-25 had a rotating tower and four MGs in it. It was a british Navy fighter in WW2. b) The Defiant scored 65 air victories in 1940 over France. Later the plane was used as a night fighter and there successful as well. Defiant as Roc Mk-I weren´t thougt for fighter to fighter combat but for the chase of bombers. Their main deficit was the slow max. speed. Not that they fired rearwards.
https://en.wikipedia.org/wiki/Blackburn_Roc
Greetings
I will have to disagree with you there as well. In the article you linked to, the Blackburn Roc had exactly ONE (yes ONE!) confirmed victory before being removed from active service and relegated to target towing, and training duties. The Boulton-Paul Defiant, while it had a few victories, didn't have the performance to be used as a dedicated fighter platform, and didn't have enough armament to be a successful night fighter either, being replaced very quickly by Mosquitos and Beaufighters.
"When the Defiant was first introduced to the public, the RAF put out a disinformation campaign, stating that the Defiant had 21 guns: four in the turret, fourteen in the wings and three cannon in the nose."
"The first operational sortie came on 12 May 1940. Defiants flew with six Spitfires of 66 Sqn, and a Ju 88 was shot down over the Netherlands. The following day, in a patrol that was a repetition of the first, Defiants claimed four Ju 87s, but were subsequently attacked by Bf 109Es. The escorting Spitfires were unable to prevent five of the six Defiants being shot down by a frontal attack."
The "Turret Fighter" concept itself was flawed from the beginning, being an idea left over from WW1 that simply refused to die during the interwar period. While rigid airships, "land battleships", "airborne fighter carriers", and Nikola Tesla's "Death Ray", died a quiet death. These ideas were relegated to the museum of oddities while other ideas such as "Cruiser Tanks", "Light Panzer Divisions", the 37mm AT Gun, The M3 Grant/Lee Tank, and fighter airplanes armed with turrets, soldiered on until enough men died proving the flaws.
“I think it is now generally agreed that the single-seater multi-gun fighter with fixed guns was the most efficient type which could have been produced for day fighting. The Defiant, after some striking initial successes, proved to be too expensive in use against fighters and was relegated to night work and to the attack of unescorted bombers. It had two serious disabilities; firstly, the brain flying the aeroplane was not the brain firing the guns: the guns could not fire within 16 degrees of the line of flight of the aeroplane and the gunner was distracted from his task by having to direct the pilot through the communication set. Secondly, the guns could not be fired below the horizontal, and it was therefore necessary to keep below the enemy. When beset by superior numbers of fighters the best course to pursue was to form a descending spiral, so that one or more Defiants should always be in a position to bring effective fire to bear. Such tactics were, however, essentially defensive, and the formation sometimes got broken up before they could be adopted. In practice, the Defiants suffered such heavy losses that it was necessary to relegate them to night fighting, or to the attack of unescorted bombers.”
- Air Chief Marshal Hugh Dowding
The argument can be made that if the Defiant had been used in a different role, and strictly against unescorted bombers, then it might have been a success. However, when designing weapons for war, you don't design weapons to fill a small niche. The most successful weapons in history have been the "all purpose" weapons. The Sherman Tank for example, was not a technical masterpiece, but there is no doubt that it won the war for us.
As I sat here thinking of the most useless weapon of WW2, the Defiant immediately came to mind. I could have listed any of the weapons that existed at the start of the war being already obsolete. Everyone knows the German Panzer Mark 2 was practically obsolete by the time it rolled into France. The Defiant stands out to me though, being a weapon designed near the start of the war. The problem was, the role envisioned for the airplane could also be fulfilled by the current Hurricanes and Spitfires, leaving the Defiant as an oddity that was only fielded as a matter of impetus. The production of the aircraft had already come too far to be stopped, and the production process could not be reversed without causing unacceptable delays in the production of new aircraft.
It's a harmless exercise to sit and argue about "what might have been", but the truth is, the Defiant was always going to be a failure, or at the least ineffective. It was designed and built at a time when far superior aircraft were already rolling off the assembly lines, and was designed for a role it was never actually used for in active service.
