Perhaps the definitive difference between a warplane and any other kind of plane is that the warplane is armed. And, while a bomber can be used for transport, it is designed specifically for delivering bombs. A pretty good range of articles discussed many aspects of armament in warplanes.

While not an active component of armament, like guns or bombs, armor to protect crew and critical systems in the aircraft is nonetheless an important element of the equipage of a warplane.
"Aircraft Armor Made Faster, Tougher"[ PDF, 8.5 MiB ] , [ HTML ] describes Breeze Corporation's process for producing face-hardened armor for use in aircraft. The article includes descriptions of the kind of testing that aircraft armor underwent.

Bombs

Both the selection of bombs for a particular mission and the handling of bombs on the ground, to get them safely into the airplane, were processes requiring specialized knowledge.

Some illustrations show bombs in action:

Guns, Gunners and Turrets

The primary offensive and defensive weaponry of warplanes of the WWII period lay in their machine guns and/or cannon(s). On many, mostly the larger, planes, machine guns (and, later, cannon) were mounted in turrets — usually power turrets, for reasons pointed out in several of the articles on turrets — in order to provide more freedom of motion for the gunner than could be provided by swivel-mounted guns.

Both the Allies and the Axis experimented with remotely operated turrets, especially ventral ("belly") turrets. Most were abandoned as not being worth the extra weight and complexity they entailed. Even the extremely advanced stations on the B-29 were of little enough value that most were removed in order to improve payload and range. The Sperry 645705-D remote-sighted ventral turret was tried on several planes, most notably the B-17E, but was replaced whenever possible with the Sperry number 645849-J spherical bottom turret, which was much more capable. Something to note here is that discussions (including articles from the Technical Training Command) mention the Bendix turrets, both remote-sighted ventral turret and dorsal turret, but the Technical Orders for the B-17 refer only to Sperry turrets and give Sperry design numbers.

While some of the reports and mission stories deal with the machine guns, the articles, ads and news-clip photos listed below either go into detail or show details of interest:

Cannon or machine gun has been an ongoing debate in military and warplane design circles since the first successful mounting of a shell-firing gun in an airplane. Proponents on both sides had good arguments and were hardly bashful about seeing them in print. At least they generally fell short of calling those who disagreed with their viewpoint traitors, unlike the situation in some other topics of "discussion."

Other weapons
Detail photos

Detail photos allow the reader, researcher or modeler to visualize the structures and arrangements more completely:

Ads

The images used in ads are of extremely variable quality, but they do help round out the picture. They were important enough at the time for the advertisers to spend considerable money to put them in front of the reader:

Drawings