Monday, May 21, 2018

Helmets - WW1, WW2

The M1 Helmet - HiGu > .The Stahlhelm - WW2 > .
2020 - Is This The World's Most Advanced Pilot Helmet? - Spark > .


The Brodie helmet, widely used during the first World War, had some serious design flaws. But thanks to those flaws we now have a staggeringly accurate map of the brain.

At the outbreak of WW1, none of the combatants were issued with any form of protection for the head other than cloth, felt, or leather headgear, designed at most to protect against saber cuts, that offered no protection from modern weapons.

When trench warfare began, the number of casualties on all sides suffering from severe head wounds (more often caused by shrapnel bullets or shell fragments than by gunfire) increased dramatically, since the head was typically the most exposed part of the body when in a trench. 

The huge number of lethal head wounds that modern artillery weapons inflicted upon the French Army led them to introduce the first modern steel helmets in the summer of 1915. The first French helmets were bowl-shaped steel "skullcaps" worn under the cloth caps. These rudimentary helmets were soon replaced by the Model 1915 Adrian helmet (Casque Adrian), designed by August-Louis Adrian. The idea was later adopted by most other combatant nations.

The British and Commonwealth troops followed with the Brodie helmet (a development of which was also later worn by US forces) and the Germans with the Stahlhelm.

The Brodie helmet is a steel combat helmet designed and patented in London in 1915 by John Leopold Brodie. The term Brodie is often misused. It is correctly applied only to the original 1915 Brodie's Steel Helmet, War Office Pattern. A modified form of it became the Helmet, steel, Mark I in Britain and the M1917 Helmet in the U.S. Colloquially, it was called the shrapnel helmet, battle bowler, Tommy helmet, tin hat, and in the United States the doughboy helmet. It was also known as the dishpan hat, tin pan hat, washbasin, battle bowler (when worn by officers), and Kelly helmet. The German Army called it the Salatschüssel (salad bowl). 

Brodie's design resembled the medieval infantry kettle hat or chapel-de-fer, unlike the German Stahlhelm, which resembled the medieval sallet. The Brodie had a shallow circular crown with a wide brim around the edge, a leather liner and a leather chinstrap. The helmet's "soup bowl" shape was designed to protect the wearer's head and shoulders from shrapnel shell projectiles bursting from above the trenches. The design allowed the use of relatively thick steel that could be formed in a single pressing while maintaining the helmet's thickness. This made it more resistant to projectiles but it offered less protection to the lower head and neck than other helmets.

The original design (Type A) was made of mild steel with a brim 1.5–2 inches (38–51 mm) wide. The Type A was in production for just a few weeks before the specification was changed and the Type B was introduced in October 1915. The specification was altered at the suggestion of Sir Robert Hadfield to a harder steel with 12% manganese content, which became known as "Hadfield steel", which was virtually impervious to shrapnel hitting from above. Ballistically this increased protection for the wearer by 10 per cent. It could withstand a .45 caliber pistol bullet traveling at 600 feet (180 m) per second fired at a distance of 10 feet (3.0 m). It also had a narrower brim and a more domed crown.

As the German army behaved hesitantly in the development of an effective head protection, some units developed provisional helmets in 1915. Stationed in the rocky area of the Vosges the Army Detachment "Gaede" recorded significantly more head injuries caused by stone and shell splinters than did troops in other sectors of the front. The artillery workshop of the Army Detachment developed a helmet that consisted of a leather cap with a steel plate (6 mm thickness). The plate protected not only the forehead but also the eyes and nose. 

Stahlhelm (plural Stahlhelme) is German for "steel helmet". The Imperial German Army began to replace the traditional boiled leather Pickelhaube (spiked combat helmet) with the Stahlhelm during World War I in 1916. The term Stahlhelm refers both to a generic steel helmet, and more specifically to the distinctive (and iconic) German design.

The Stahlhelm, with its distinctive "coal scuttle" shape, was instantly recognizable and became a common element of military propaganda on both sides, just like the Pickelhaube before it.

In early 1915, Dr. Friedrich Schwerd of the Technical Institute of Hanover had carried out a study of head wounds suffered during trench warfare and submitted a recommendation for steel helmets, shortly after which he was ordered to Berlin. Schwerd then undertook the task of designing and producing a suitable helmet, broadly based on the 15th-century sallet, which provided good protection for the head and neck.

After lengthy development work, which included testing a selection of German and Allied headgear, the first Stahlhelme were tested in November 1915 at the Kummersdorf Proving Ground and then field tested by the 1st Assault Battalion. Thirty thousand examples were ordered, but it was not approved for general issue until New Year of 1916, hence it is most usually referred to as the "Model 1916". In February 1916 it was distributed to troops at Verdun, following which the incidence of serious head injuries fell dramatically. The first German troops to use this helmet were the stormtroopers of the Sturm-Bataillon Nr. 5 (Rohr), which was commanded by captain Willy Rohr.

In contrast to the Hadfield steel used in the British Brodie helmet, the Germans used a harder martensitic silicon/nickel steel. As a result, and also due to the helmet's form, the Stahlhelm had to be formed in heated dies at a greater unit cost than the British helmet, which could be formed in one piece.

From 1936, the Mark I Brodie helmet was fitted with an improved liner and an elasticated (actually, sprung) webbing chin strap. This final variant served until late 1940, when it was superseded by the slightly modified Mk II, which served the British and Commonwealth forces throughout World War II. British paratroopers and airborne forces used the Helmet Steel Airborne Troop.

Several Commonwealth nations, such as AustraliaNew ZealandCanada and South Africa, produced local versions of the MK II, which can be distinguished from those made in Britain.

During this period, the helmet was also used by the police, the fire brigade and ARP wardens in Britain. The helmets for the ARP wardens came in two principal variants, black with a white "W" for wardens and white with a black "W" for senior ranks (additional black stripes denoted seniority within the warden service); however numerous different patterns were used. A civilian pattern was also available for private purchase, known as the Zuckerman helmet, which was a little deeper but made from ordinary mild steel.

Hobart's Funnies

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US Combat Engineers 

D-Day innovations ..

Major General Sir Percy Cleghorn Stanley Hobart KBE, CB, DSO, MC (14 June 1885 – 19 February 1957), also known as "Hobo", was a British military engineer noted for his command of the 79th Armoured Division during WW2. He was responsible for many of the specialised armoured vehicles ("Hobart's Funnies") that took part in the invasion of Normandy and later actions.

Funnies of the 79th Armoured Division and its inspirational leader Major General Percy Hobart

The Dieppe Raid in August 1942 had demonstrated the inability of regular tanks and infantry to cope with fortified obstacles in an amphibious landing. This showed the need for specialised vehicles to cope with natural and man-made obstructions during and after the Allied invasion of Europe.

In March 1943, Hobart's 79th Armoured was about to be disbanded, due to lack of resources, but the Chief of the Imperial General Staff (CIGS), General Sir Alan Brooke, in a "happy brainwave", invited Hobart to convert his division into a unit of specialised armour. Hobart was reputedly suspicious at first and conferred with Liddell Hart before accepting, with the assurance that it would be an operational unit with a combat role. The unit was renamed the "79th (Experimental) Armoured Division Royal Engineers". Unit insignia was a black bull's head with flaring nostrils superimposed over a yellow triangle; this was carried proudly on every vehicle. Hobart's brother-in-law, General Sir Bernard Montgomery, informed the American general Dwight D. Eisenhower of his need to build specialised tanks.

Under Hobart's leadership, the 79th assembled units of modified tank designs collectively nicknamed "Hobart's Funnies". These were used in the Normandy landings and were credited with helping the Allies get ashore. The 79th's vehicles were offered to all of the forces taking part in the landings of Operation Overlord, but the Americans declined all except the amphibious Sherman DD tank. Liddell Hart said of him: "To have moulded the best two British armoured divisions of the war was an outstanding achievement, but Hobart made it a "hat trick" by his subsequent training of the specialised 79th Armoured Division, the decisive factor on D-Day."

The vehicles of the 79th did not deploy as units together but were attached to other units. By the end of the war the 79th had almost seven thousand vehicles. The 79th Armoured Division was disbanded on 20 August 1945. 

High vs Low Explosives

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gunpowder versus semtex

An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of lightheatsound, and pressure. An explosive charge is a measured quantity of explosive material, which may either be composed solely of one ingredient or be a mixture containing at least two substances.

The potential energy stored in an explosive material may, for example, be

Explosive materials may be categorized by the speed at which they expand. Materials that detonate (the front of the chemical reaction moves faster through the material than the speed of sound) are said to be "high explosives" and materials that deflagrate are said to be "low explosives". Explosives may also be categorized by their sensitivitySensitive materials that can be initiated by a relatively small amount of heat or pressure are primary explosives and materials that are relatively insensitive are secondary or tertiary explosives.

wide variety of chemicals can explode; a smaller number are manufactured specifically for the purpose of being used as explosives. The remainder are too dangerous, sensitive, toxic, expensive, unstable, or prone to decomposition or degradation over short time spans.

In contrast, some materials are merely combustible or flammable if they burn without exploding.

The distinction, however, is not razor-sharp. Certain materials—dusts, powders, gases, or volatile organic liquids—may be simply combustible or flammable under ordinary conditions, but become explosive in specific situations or forms, such as dispersed airborne clouds, or confinement or sudden release.

Explosive weapon .

Hypersonic Missiles

2021 Is A Hypersonic Missile Worth $3.8 Billion? The Value of  Hypersonics - CoCa > .
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23-6-11 Rocket Roulette: Ruscia uses drones & missiles against Ukraine - U24 > .
22-10-1 America's Missile Defense Problem - Poly > .
22-4-8 How Many Nuclear Missiles Can the United States Intercept? - nwyt > .


Hypersonic Missiles ..
Hypersonic Missiles versus ICBMs ..

Hypersonic Missiles versus ICBMs

23-8-10 ‘Detect, Control, Engage’: The Aegis Concept - UNI > .


Hypersonic Missiles ..
Hypersonic Missiles versus ICBMs ..

Comment 1 Speed has very little to do with penetrating Missile Defences. It’s the high altitude flight profile that reduces the engagement envelope of a SAM. For instance, Zircon has a flight ceiling of 30 km which is twice that of supersonic AShMs like Oniks/Brahmos. This puts it beyond the envelope of ESSM, older Block SM-2 as well as Aster-15/30 until the terminal phase. 

The SM-6 with ~35 km flight ceiling can intercept Zircon throughout its flight but only from reduced range. The engagement envelope can be reduced to 1/3 when intercepting a high altitude Mach 8+ target because of very different flight trajectory of the interceptor (negligible lofting). So SM-6 with ~400 km range against aerodynamic target may only have around 150 km range against Zircon. Medium range ballistic missiles (MRBM) like DF-21D and Kinzhal doesn’t pose a huge threat to Aegis which can engage them from late boost-phase and mid-phase with exo-atmospheric SM-3 to terminal phase with SM-6, but they do create a challenge for Navies lacking an exo-atmospheric interceptor as they’re only limited to terminal phase interception. 

Finally, HGVs pose a significant threat as they can exploit a big gap that exist today. Current Missile Defences can’t intercept anything between the 40 to 80 km altitude. The SM-3 can engage exo-atmospheric targets but the next in-line SM-6 Block IA has a flight ceiling around 35 km, leaving a large gap in the upper atmosphere that’s beyond the engagement envelope. 

HGVs like DF-17 with an endo-atmospheric flight ceiling around 60 km exploits this gap. Some ballistic missiles also fly a depressed trajectory for the same reason, although they’re quite limited and face a huge range-penalty when doing so. 
Deployment of HGVs like DF-17 is what prompted the US Navy in developing a modified version of SM-6, the SM-6 Block IB with 55% bigger motor (21″ vs. 13.5″) which will significantly increase both speed and flight ceiling. The SM-6 Block IB is scheduled to be tested against a HGV later this year and will be operational around 2023.

Comment 2: Sensationalized weapon. HGVs lose speed, terminal velocity is Mach.3 after 7000km. Zircon averaged Mach.4.9 according to the data they released, it only reached Mach.8+ at 30km altitude mid flight. Still useful as a prompt strike weapon but not undefeatable.

Comment 3: Ground based midcourse defense which is the fastest hypersonic missile in the world capable of mach 33 built by the US or the SM3 which is a midcourse phase ICBM interceptor. This video has a lot wrong though. 
Hypersonic missiles are covered in plasma, any IRST let alone AESA radar can track it. Shooting it down is where it is harder. Tracking it is easier then a subsonic sea skimming, under the radar horizon missile. 
They literally stated hypersonic missiles fly below the radar horizon like a god damn sub sonic cruise missile which is hilarious. The radar horizon has to do with Earths curvature and not space, where these missiles fly... LOL. Hypersonic missiles are also not maneuverable in their terminal phase. They literally have to shut their engines off, can lose stability because they have no engine power, and even self destruct from the thicker air density all according to the Russians own patent. They literally got someone who had no idea what they are talking about to make stuff up. That's amazing to me. Say they could maneuver, using the mach 10 speed stated here that's 3.4km/s rounding down for ease say you wanted to move a single degree for 5 seconds at 3km/s you would be off course 15km. Math is math, patents are patents. Bad video. 
"Russian patent number 2579409 relates to the field of rocket technology, and more specifically to hypersonic cruise missiles equipped with a hypersonic ramjet engine. The invention describes a method of application and device hypersonic cruise missile (CRPD), allowing to solve the problem of performing a combat mission to destroy ground and surface targets of such a missile. The described invention is designed to maximize the combat potential of the CMP with the scramjet. 
The design mode for the scramjet are high-altitude cruise conditions while maintaining the estimated cruise speed, and the need to reduce the altitude and flight speed creates difficult technical problems due to the fact that: an engine designed to perform a hypersonic mid-flight at high altitude is not able to continue to work at low-altitude trajectory sections associated with a decrease in the flight number M, hence, the rocket must approach the ground or surface target with an inactive engine; characteristics of sustainability and controllability of CRPD with inactive scramjet significantly deteriorate, loss of stability becomes possible; there is also a danger of destruction of the scramjet design due to the increase in pressure in the flow part of the engine while reducing the CMP from the march height before hitting the target."

sī vīs pācem, parā bellum

igitur quī dēsīderat pācem praeparet bellum    therefore, he who desires peace, let him prepare for war sī vīs pācem, parā bellum if you wan...