CREWMEN of a B-17 had a surprise recently while flying over a quiet sector of England when a 20 mm. shell exploded in the left horizontal stabilizer. They had reason to be surprised. There wasn’t an enemy plane in sight.
After the big bomber had landed, Captain Henry J. Schmidt, an engineering officer with the Eighth Air Force, began investigating. He found that the B-17 had been carrying the shell around ever since it had attacked German installations in France some three weeks before. During that attack the shell had pierced the stabilizer without exploding. The hole it made was subsequently repaired, but without knowledge on anyone’s part that the missile was still in the ship.
Recommended length of machine gun length for B-29 gunners. Source: Combat Crew Manual, XX Bomber Command, December 1944.
LENGTH OF BURSTS
There are several factors to consider in arriving at an answer to the question of how long a burst it is practical to fire. The ammunition has a high degree of accuracy. At 600 yards, when fired from an accuracy rifle held in a V-block, it will group in a circle 18″ in diameter. When fired single shot, using an aircraft machine gun on a tripod mount, tests have shown a 20″ circle of fire. In a burst of 10 or 12 on the same mount the group was approximately five feet. When longer bursts were fired, it was observed that the gun soon lost accuracy, even though it remained relatively stationary in the mount. When over fifty rounds were fired, in one burst, the projectiles tumbled in flight and dispersed over a 75 foot area at 600 yards. When the barrel has been overheated, it will be found that it cannot be relied upon for further accuracy even though the lands and grooves measure up well and the barrel, to all appearances, seems good. If the exterior of the barrel has a burned appearance, it should be tested by ordnance before further use. When a barrel becomes over-heated it expands to such an extent that the muzzle velocity decreases several hundred feet per second. This decrease continues as the barrel continues to expand, until a point is reached where tumbling of the projectiles takes place and controlled fire is reduced to a few hundred feet. The accuracy of the fire delivered, therefore, depends not only on how steadily the gun is held, but also on the length of the burst, and the condition of the barrel. If a gunner fires short bursts of three to five rounds, constantly using his sights, he will have a tight group and a high degree of accuracy. This is the most effective method of firing your machine guns.
The old Aberdeen Museum Tiger I tank is finally being shipped from RAF Alconbury, England back to the United States to the U.S. Army Armor and Cavalry Museum at Fort Benning, Ga. At the Fort Benning museum, the German Tiger I is scheduled for complete restoration. This particular Tiger I originally served with the German sPzAbt. 501 in North Africa. The Tiger was captured by U.S. forces in 1943, and sent to Aberdeen Proving Grounds for evaluation.
One of the most feared and powerful tanks of its time is making its way to the United States courtesy of the 48th Logistics Readiness Squadron. The German Tiger 1, World War II era tank, is to be shipped from RAF Alconbury, England, to the U.S. Army Armor and Cavalry Museum at Fort Benning, Ga., for repair and full restoration….
“There are only six known Tiger 1s that are still in one piece that are left in the world,” said Len Dyer, Director of the Army Armor and Cavalry museum. “This particular one was captured by the British in Tunis, North Africa, in 1943. She has plenty of combat action and a few combat scars that have had repair work done them.”
Although the tank is now being broken down to be relocated, the battle scars that have since been patched can still be seen on several parts of the tank.
This unique task of moving this battle hardened tank came down from the U.S. Army to the 48th LRS.
“I received an email from the Secretary of the Army requesting whether we could support the moving of this back to the United States and talking to the 48th LRS commander we decided we would go ahead and try to help the Army get this tank home,” said Bill Pratt, 48th LRS Transportation Management Office chief of cargo movement….
This particular cargo is slated to be completely broken down, cleaned, and made ready to be taken back to the U.S. within the next month to join other pieces of military history at the Fort Benning U.S. Army Armor and Cavalry Museum.
“Dead Reckoning” from Navigators’ Information File, Headquarters Army Air Forces, War Department, 1944:
The successful termination of any flight depends on dead reckoning. Navigators returning from all over the world–from the Aleutians, where weather is always a problem; from the Marianas, where long over-water flights are made constantly; from China, the land of no maps–stress this fact: Dead reckoning is the basis of all navigation. Use it.
Celestial, pilotage, radio, and Loran all are aids to dead reckoning. Use them only as aids.
Dead reckoning is based upon the solution of the time-speed-distance problem, and you are primarily a dead-reckoning navigator. Pilots dead reckon on every flight, though they are not always aware of this fact. Your work must be more exact, of course, than a pilot’s mental calculations. And you must know and use every form of dead reckoning available to you on every flight you make.
If you make but one resolve as a navigator, it should be, “I’ll dead reckon on every flight from the time we take off until the wheels are back on the ground.” If you do less than this you are not doing your job–and that can easily prove fatal.
To do accurate work you must be able to recognize all possible errors in your computations and know how to compensate for them. Furthermore, you must understand the navigation problems you are likely to encounter and plan your solutions of them before you leave the ground. Constant air practice then gives you needed confidence.
Prepare adequately on the ground to make your work as easy as possible in the air. The distractions of flight conditions such as combat, weather, and lack of oxygen, and the inconveniences of fatigue and cramped quarters unavoidably complicate your job. Don’t make it more difficult for yourself.
Diagram of M4A2 Sherman tank ammunition storage from TM 9-731B: Medium Tank M4A2, War Department Technical Manual, Washington, January 13, 1943.
Figure 8A--Ammunition Stowage
97 rounds 75 mm 50% HE 40% AP 10% WP (smoke)
15 rounds–Left sponson forward of water can rack. 17 rounds–Right sponson next to assistant driver. 15 rounds–Right sponson forward of engine compartment bulkhead. 30 rounds–On floor under turret basket to rear of escape door. 8 rounds–On turret “ready” rack floor. 12 rounds–In ready clips around turret basket step.
300 rounds caliber .50 80% AP 20% tracer
150 rounds–In three 50-round boxes right sponson next to assistant driver. 150 rounds–In three 50-round boxes strapped to turret floor.
6750 rounds caliber .30 80% AP 20% tracer
4500 rounds–In eighteen 250-round expendable boxes under turret basket to rear of driver. 1750 rounds–In seven 250-round expendable boxes, on turret floor under 75 mm gun. 230 rounds–One 250-round expendable box on “ready” rack of bow gun. 250 rounds–In one 250-round expendable box on “ready” rack of turret machine gun.
Comparison of 37-mm Ammunition from WW2 technical manual: TM 9-1901: Artillery Ammunition, War Department Technical Manual, June 1944:
FIXED AND SEMIFIXED ROUNDS AND SEPARATE-LOADING PROJECTILES: A - MK.II A1, PRACTICE ROUND FOR 37-MM GUN SUBCALIBER, M1916 B - M56 H.E ROUND FOR 37-MM GUNS, M4 AND M10 C - M56 H.E. ROUND FOR 37-MM GUNS, M1A2 AND M9 D - M63 H.E. ROUND FOR 37-MM GUNS M3, M3A1, M5, M5A1, AND M6
The importance of the modern power gun turret to U.S. bombers in WW2 from Aircrewman’s Gunnery Manual, Aviation Training Division, Office of the Chief of Naval Operations, U.S. Navy, 1944
Thanks to the Turret… THE BOMBER FIGHTS BACK
Without the men who invented the turret, today’s great bombing missions would be impossible. For without turrets, the bomber would be almost as helpless over enemy territory as an ordinary transport plane without a single gun.
No one knows exactly who should get credit for inventing the modern turret. The first crude models came out in the 1920′s. One was a circular mount, illustrated on this page, which the United States developed to put a little flexibility into bomber guns. The Russians tried a movable platform, cranked by hand, in which the gunner sat right out in the open, fighting the slipstream as well as the enemy.
The modern power turret–driven by electricity and mounted inside the bomber–was developed after many experiments in the 1930′s and proved its worth in action in the second year of World War II. Its effect on air strategy was spectacular. At last the bomber–heavier and slower than the fighter plane–could really fight back.
For turrets–little blisters of plexiglas or safety glass, bristling with caliber .50s, swinging around to meet enemy fighters no matter where they come from–enable the bomber to match the enemy slug for slug in an air battle.
Approach an American bomber today, from any angle, and you will see a turret whose guns could be turned toward you in an instant.
The top turret swings in a full circle; its guns move up and down from straight out to nearly straight up; it protects the whole top of the plane.
A safe one-wheel landing by a PV Ventura on a Pacific Island during WW2 from Naval Aviation News, March 15, 1945.
A PV piloted by a Lieutenant Commander made a successful one-wheel landing on a Pacific island airstrip without injuring the crew or dislodging a 100-lb. bomb no one knew was stuck in the bomb bay. The pilot’s report follows:
While over an enemy target the plane received one hit in the left engine nacelle which severed the hydraulic line and broke the engine mount near the fire wall. The hydraulic system lost all pressure. On return to the field the hand pump would not extend the landing gear.
VENTURA, WITH 100-LB. BOMB IN BAY, MAKES A LANDING ON PACIFIC ISLAND WITH LITTLE DAMAGE
Using the emergency extension system only extended the left main mount; the right wheel could not be released from the mechanical uplocks as the cable broke. The tail wheel extended but would not lock. I dropped both external gas tanks and released the escape hatch. My approach was higher than normal and at 110 knots indicated. Keeping the left wing low, I slipped the plane to hold it straight and lose my additional altitude without picking up excessive speed.
As the plane touched the ground on the left wheel, the radioman cut the master electrical switch, I put both engines in idle cut-off and cut the ignition switches. All other electrical gear was cut off in the final approach. The landing was full stalled without flap. Aileron and rudder control was excellent and no trouble was experienced holding up the right wing.
At 58 knots IAS, aileron control was lost, causing the right wing to drop onto the runway. The plane swerved and turned about 150° over an embankment and stopped. The tail wheel being unlocked prevented damage to the empennage. Over-all damage to the plane was surprisingly small and the left main gear was not damaged. Neither engine suffered sudden stoppage and no personnel received any injury, having taken ditching stations before the forced landing was made.
ENEMY SHELLS RUINED THE PLANE'S HYDRAULIC CONTROL, FORCING PV TO COME IN ON ONE WHEEL