The B-29 Turret System: An Expensive, Effective Mechanical Masterpiece

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

In the book "Friendly Monster" a B-29 pilot describes how his crew had to work hard on the gunnery system to get it to perform properly. The official USAAF evaluation test showed the system was somewhat flawed but after the crews got it calibrated and exercised they reported the ability to hit enemy fighters at significantly greater distances than hand held guns.
 
A good part of the distance increase in accuracy is an underappreciated aspect of gun turret control system. The system is a servomechanism which brings the gun turret pointing into alignment with the gunsight pointing. As the gunsight moves to a different point, the system moves the gun turret to match it. The underappreciated aspect of the system is: if the turret is moved and the gunsight remains fixed, the system will move the turret back into alignment. The forces that can move the gun turret are wind loading and recoil. Consequently any recoil motion is reduced by the action of the control system, increasing the accuracy of the shot.
 
When a remote turret system was installed on the P-61 they could not hit anything with it. Then a very experienced MSgt gunner had a thought, and they tried out his idea. The problem was that when you were the faster moving attacker rather than the defending bomber you had to use reverse lead - shoot behind the target rather than in front of it. Now just think. If P-61 was being attacked by a faster airplane they had to shoot at it one way but if they were attacking a slower aircraft they had to shoot at it a different way.
 
When a remote turret system was installed on the P-61 they could not hit anything with it. Then a very experienced MSgt gunner had a thought, and they tried out his idea. The problem was that when you were the faster moving attacker rather than the defending bomber you had to use reverse lead - shoot behind the target rather than in front of it. Now just think. If P-61 was being attacked by a faster airplane they had to shoot at it one way but if they were attacking a slower aircraft they had to shoot at it a different way.
The chin turret on the B-17G was the first combat installation of a remote control turret.

Many good results were reported from its use. Granted there won't be much deflection in its prime role as defending against head-on fighter attacks.

The B-29 system and the P-61 system designers were able to learn from the B-17 chin turret experience.
 
The chin turret on the B-17G was the first combat installation of a remote control turret.

The B-17G's chin turret was adopted from the failed YB-40 gunship concept which first saw combat in 1942. The B-17F-DL was first fitted with the turret and then incorporated into the G series.

However, before the YB-40's combat debut, the Me210, which had remote gun turrets, saw combat several months prior.

As it happens, both the Me210 and Ar240 were designed with remote turrets several years before the YB-40.
 
The chin turret on the B-17G was the first combat installation of a remote control turret.
The B-25B and B-17E had it with the initially installed lower lower turret. The results were terrible and only managed to give the operators headaches. The manned turret replaced it on the B-17. On the B-25, it was removed on the Doolittle Raid airplanes and units in the Med that were concerned above covering the low six o'clock position installed tail gunner positions, similar in design to those later used on the B-25H and J, but a bit smaller and cruder.
 
The chin turret on the B-17G was the first combat installation of a remote control turret.

No it wasn't. The Piaggio P.108 had remotely operated guns at least two years before the B-17G and these saw combat; the Italians complained because the turrets were prone to jamming and because they were remotely operated they could not reach the guns to unjam them. The other issue the P.108's remote guns suffered was vibration and too small an ammunition supply per turret.
 

Users who are viewing this thread

Back