Water Reuse An International Survey Of Current Practice: Fill & Download for Free

EARLY ORIGINSThe English have a documented history of English units back to at least the Magna Carta (1215 AD), with numerous variations on units, and several rounds of standardization of units.The United States was founded as 13 English colonies. Naturally, they used the same English units as England itself.AMERICA ALMOST ADOPTS DECIMAL MEASURESWhen the United States broke from the rest of Great Britain, in the Constitution (1789) they gave Congress the right to set weights and measures. The first President, George Washington, assigned that job to his Secretary of State, Thomas Jefferson, to develop and present to Congress a proposal for uniform weights and measures.Jefferson was uniquely well qualified to do so. He was a “gentleman-scientist”, and understood metrology. He had been Ambassador to France, and was in touch with French (and British) scientists who were ALSO interested in establishing an improved system of measures. He had actually worked on, discussed, and debated various potential new standards-based measures.At the time, people understood that a coherent system of units could be created by selecting a standard length unit, squaring and cubing that to measure area and volume, and then selecting water’s density as the way to extend volume into weight or mass. A century earlier, a decimal method of multiplying or dividing units had been proposed. All that was needed was a standard length that could be accepted by all nations. To be accepted by all nations, it had to be scientifically derived, rather than specified as, for example, the length of some particular ruler’s outstretched arm (yard).In conjunction with French scientists, Jefferson favored establishing a yard, with decimal fractions and multiples, based on the Seconds Pendulum. This would be the length of a pendulum whose period was exactly one second (tick … tock…). Specifically, Jefferson favored the inverted rod pendulum, located at 45 degrees latitude. (While this flattered the French, with Paris at 45 degrees North, it was defensible as the mid-point between equator and pole, and thus positioned at an average Earth radius. He gave up an earlier proposal that it be at the latitude of Washington, D.C.) In May, 1790, the French propose a seconds pendulum-based metre.On July 13, 1790, Jefferson submitted two alternative proposals to the First Congress.The first would be a new, decimal system, based on the Seconds Pendulum. A foot would be 1/3 of the pendulum length, and length units would be inches of 1/10 foot, miles of 10,000 feet, etc.The second would be a traditional English system, but with consolidated units — e.g., only ONE set of units for fluid volume, instead of one gallon for wine, and a different size gallon for ale.If Congress selected Jefferson’s first proposal, the US would have been the first nation on Earth to adopt decimal measures. Unfortunately, the First Congress had many other matters to consider, and both of Jefferson’s proposals languished and were tabled. The only decimal measure adopted by Congress was in money and coinage, where English pounds/shillings/pence and Spanish pieces of 8 were both abandoned, and a new decimal Dollar, cent (1/100 dollar), and Eagle (10 dollars) created.The People continued using their traditional English units.The French could no longer contain themselves, and started developing their own decimal system. Though they had previously agreed with Jefferson to use the Seconds Pendulum, in 1791 the French Academy switched to 1/10,000,000 of the distance from the Equator to the Pole (quarter circumference of the Earth along a meridian). They commenced a project to measure a part of the Earth, and estimate that quarter circumference, and to establish the metre (and from that, the kilogram and the litre). The insular nature of this change in length standards (funded strictly by the French Academy of Sciences — originally by the King, and then by the Revolutionary government), ensured that this became solely a French project, rather than an international project. The metre and kilogram were released as provisional standards in 1795, and formalized the final standard in 1799.AMERICA DEFAULTS TO ENGLISH UNITSAt the end of 1793, Jefferson retired to private life at his plantation. It is possible he did it because of political ambitions, impossible to pursue while part of Washington’s cabinet. (Indeed, he ran for President in 1796, coming in second and thus becoming John Adams’ Vice President in 1797; and was then elected President in 1800.)In 1795, a bill for weights and measures was again taken up in Congress, but again tabled — until the end of the Northwest Indian War. This war with Native Americans in the Northwest territory (Ohio and other territories farther west) ended, and US settlers were about to go and make claims in the new territory. Congress needed to immediately agree to a standard measure to survey the new territory, before the settlers started their claims.Congress finally passed "an Act for the sale of land of the United States in the territory northwest of the River Ohio, and above the mouth of the Kentucky River", on May 18, 1796, including the specification that the territory was to be surveyed in English Miles and Gunter’s Chains (22 yards). This was the first specification of what is now the USCS units. Other types of English units continued to be used in the Customs Houses, managed by the Treasury Department.THE BRITISH DIVERGEJust as Americans had selected from amongst the several English units to pick a set of USCS standards, three decades later (1824) the British determined to improve their standards for their burgeoning, post-American, British Empire. They tightened standards for the foot and pound, and in the same decimalization spirit as Jefferson and the French, developed a new “decimal” gallon, based on exactly 10 pounds of water. The British also selected one of the stone units in use, and eliminated all others, making their stone, hundredweight, and ton different from the Americans. This new Imperial system of units went forward in 1826.AMERICAN UPDATESBy the 1830s, there were problems with America’s “English Units”. At the several different customs houses (one at each major port), they had measuring standards for imported products which were slightly different. Ship captains learned which ports had the measure that minimized the tariffs on their cargo. Another overhaul of the weights and measures was required.One option was to improve the standardization and uniformity of the English unit standards. Another was to adopt a competing system. Jefferson’s decimal system was not used anywhere in the world — but the core of the metric system, metres and kilograms, had been put into practice in France. Unfortunately for metric lovers, France had actually rebelled against and (temporarily) abandoned use of the metric system when the US reconsidered its units. The metric system was not ready for international adoption. Throughout the 1800s, many in the US considered USCS to be Christian, and objected to the French metric system as atheistic, like the Republic. Additionally, even in the UK with its new Imperial System, an 1834 fire destroyed its yard and pound standards.Instead of a foreign system, the US decided to tighten standardization to its own English unit standards. In 1855, newly-made British standards were so good, that, for the yard and pound, the US adopted one set of them as its national standards. (Obviously, not for the gallon, stone, etc. that were unique to Imperial measures.)SEMI-METRICATIONIn 1866, the US passed a law that allowed, but did not require, the use of the metric system. A set of conversions was included in the law,(3937 yards = 3600 m; 1 pound = 0.4535924277 kilogram)In 1875, the Convention of the Metre was signed. The US was a principal, one of 17 original signatories. (Not that this changed US measures.) Metric standards (metal metre and kilogram) arrived in the US in 1890. Melvil Dewey (famed for his library classification system) formed a company to make his fortune in metric rulers. (It didn’t.)On April 5, 1893, the superintendent of the US Coast and Geodetic Survey Thomas Mendenhall, charged with the survey standards for the US, issued the “Mendenhall Order”. He determined that the metric standards available in the US were more stable than the old USCS standards, and ordered that the metric standards would henceforth set the standard for USCS measures, using the 1866 conversions. USCS units have been defined in metric terms ever since, changing when the metric standards changed.In 1901, a coherent system of metric units was first proposed, integrating electrical units and defining the Joule. However, this metric system was not immediately accepted, and MKS, cgs, and other metric variants persisted.In 1959, the US and UK agreed to adjust their feet and pounds very slightly, to a precise, common, metric definition, the International Foot and International Pound. (The US and UK conversions from metric standards had been very slightly different.) (The US retains the “survey foot” to reflect the length that had been in use when surveys were done.)FINALLY, in 1960, the International System (SI) was adopted by the world’s scientists, and one single, coherent metric system available to the world. The metre was redefined at a number of wavelengths of light, and its metal standard was retired to a museum. (The kilogram is still a metal standard, though there are proposals to replace that too.) Time was similarly redefined, and was no longer based on the actual Earth rotation, which at the millisecond/century level, was both slowing and irregular.1968–71, as the UK started its metric conversion, the US studied a potential conversion to the new SI system. Use of metric seemed to be increasing, with US technology often using metric, and increasing foreign trade.In 1970, Pepsi distinguished itself from Coke by adopting the metric two liter plastic soft drink bottle, replacing glass half gallons, and advertised for people to join “the Pepsi generation!” (It helped that the new plastic bottles were much cheaper than the half gallon glass bottles, and didn’t require returning and washing before reusing.)In 1973, ANSI formed the American National Metric Council. It held a series of metric conferences in various industries from 1975 through 1993.In 1974, the US Treasury Department issued metric regulations for standard wine bottles, including the now-ubiquitous 750 ml bottle. The Treasury department specifies this, to obtain proper taxation for the US. (27 CFR 4.71)In 1975, Congress passed a law making the metric system the preferred system of units for industry and commerce, and established the US Metric Board (USBM). A grand scheme of public relations pushes and ads for metrication, and metrication boards for several industries, were started. However, actual USE of the metric system was voluntary.In 1976, the nation’s bicentennial, the US changed the liquor industry to metric units — although keeping very similar sizes to their USCS predecessors. By 1979, 38 USCS sized bottles were replaced by six metric sizes. A fifth (1/5 gallon*) became 750 ml (shrunk by 7 ml). A half gallon became 1.75 L (almost 5 oz smaller). The liquor industry promised the new slightly smaller metric bottles would be accompanied by a proportional reduction in price. (lol !) Distillers promoted their drinks as “a great way to learn the metric system!” (Note: EU standards require 700 ml bottles of liquor, and so although metric, US and EU standards remain different.)American water had long been quite drinkable out of the tap, and bottled water rare to non-existant. But in 1977, Perrier launched an advertising campaign for imported French water. Together with Evian water, they introduced metric units at the same time as bottled water. Bottled water, often (though not always) in metric sizes, grew from 16 brands and 1 gallon per capita in 1975 to 195 brands and 79 L (21 gal) per capita in the 2010s.American science managed a wholesale conversion to metric, joining in an international community. The automobile industry, caught after the 1973 petroleum crisis, slowly started internationalizing — eventually becoming entirely international in both manufacturing locations and in their SI units.But millions of schoolchildren in the 1970s were trained in “metric conversion”. Rather than simply teaching use of metric units, children were schooled in pound-kilogram, meter-foot, and gallon-liter conversions. The US populace began to perceive the metric system not as a way of life, but as an annoying, arbitrary, and non-useful arithmetic problem.METRICATION RECEDES TO A WHIMPERBy 1981, the USMB reported it lacked the enabling mechanisms that needed enacting by Congress, and the new President Reagan focused on other issues instead of measures. USMB was disbanded in 1982.In 1988, Congress again encouraged metrication, and designated metric as the preferred system of weights and measures for US trade and commerce. But it only encouraged government assistance as industry and business voluntarily converted to metric measures. It required the Federal government to use the metric system after 1992 — except where it cost more than using USCS units. Given that all goods were available in USCS units and to USCS standards (e.g., 2 x 4 ft light panels), but not to metric standards (e.g. 60 x 120 cm light panels), almost everything remained purchased in USCS units. Bills were created in 1992–1993 to ban use of metric units on US highways, but these failed.In 1994, Federal packaging law required metric units to be added to USCS units on consumer products.The US Department of Transportation released metric highway standards for use in 2000, but the plan was cancelled by Congress’s 1998 Highway Bill.Use of the Greek (and metric) “K” for thousands and “M” for millions has nearly replaced the Latin “M” for thousands and “MM” for millions, except in certain obscure financial corners.Efforts to metricate continue, ineffectually. In 2010, NIST (the US National Institute of Standards & Technology) called to amend Federal packaging law to permit metric-only labels, instead of dual system labels. Congress has not acted on this. In 2013, an online petition was filed with the Obama administration to make metric the US standard. The Obama admininstration response was that the nation is “bilingual”in its units, and choosing units is an individual freedom. Hawaii and Oregon both considered, but did not adopt, metrication bills. It is unclear that these would have withstood judicial challenge, given the US Constitution’s allocation of standards to the Federal Government, as well as oversight over interstate commerce.Industries and companies that want to use metric units, do. The rest continue with USCS units.There is no current impetus in the US to change measurement systems, and President Trump’s “America First” agenda is unlikely to prefer an international system.Jefferson’s Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States - Wikipediahttps://en.wikipedia.org/wiki/Thomas_JeffersonUnited States customary units - WikipediaMetre Convention - WikipediaMendenhall Order - WikipediaHistory of the metric system - WikipediaMetrication in the United States - WikipediaMetre - WikipediaTwo-liter bottle - WikipediaBottled water in the United States - WikipediaLiquor Industry Converts to Metric System (NY Times)Why are large liquids measured in metric liters instead of in imperial fluid ounces in the US?Bill Spencer's answer to Why does a bottle of wine hold 750 ml?* Before its Prohibition, the American 1/5 gallon size bottle was used because taxes were levied on all spirits in quart (1/4 gallon) bottles or larger. Conveniently, 1/5 US gallon was very close to 1/6 Imperial gallon, allowing the same bottles to be used for both, with a slightly different fill.

Q. Were some of WW2 kamikaze planes launched with their wheels dropped at takeoff to reduce weight, increase range, and limit a return ability for the pilot? Also, were these reused for the next pilot?Ohka Model 11 replica at the Yasukuni ShrineYokosuka MXY-7 Ohka - WikipediaThe Kamikaze These Baka-Bombs drop their wheels on take off.IJN - KAMIKAZEJap Pilots Ride to DEATH on Flying Bombs - Modern Mechanix (Apr, 1933)Yokosuka MXY7 Ohka [Oka] Japanese Flying Bomb (fiddlersgreen.net) most detailedYokosuka MXY-7 Ohka - WikipediaThe Yokosuka MXY-7 Ohka (櫻花 Ōka, "cherry blossom"; 桜花 in modern orthography) was a purpose-built, rocket-powered human-guided kamikaze attack aircraft employed by Japan against Allied ships towards the end of World War II. United States sailors gave the aircraft the nickname Baka (ばか, "fool" or "idiot").Yūshūkan war museum.Yokosuka MXY7-K1 Ohka (Cherry Blossom)The KamikazeYokusuka MXY7 "Baka-Bomb" was a rocket-powered flying bomb--laden with high explosives. Most of the Kamikaze's were whatever the Japanese could find that would fly by this time in the war. These Baka-Bombs drop their wheels on take off; and they can not land again; and look like a flying torpedo.IJN - KAMIKAZEThe Ohka suicide rocket-missles of the Thunder-Gods Corps.The Yokosuka MXY-7 Ohka, ("cherry blossom" ) was a purpose-built, rocket powered kamikaze suicide missile employed by Japan towards the end of World War II. The United States gave the aircraft the name Baka (Japanese for "idiot").It was a manned flying bomb that was carried underneath a Mitsubishi G4M "Betty", Yokosuka P1Y Ginga "Frances" (guided Type 22) or planned Heavy Nakajima G8N Renzan "Rita" (transport type 43A/B) bomber to within range of its target; on release, the pilot would first glide toward the target and when close enough he would fire the Ohka's rocket engine and guide the missile towards the ship that he intended to destroy. The final approach was almost unstoppable (especially for Type 11) because the aircraft gained tremendous speed. Later versions were designed to be launched from coastal air bases and caves, and even from submarines equipped with aircraft catapults, although none were actually used this way.The World's Best Photos of kamikaze and ohkaConceived by Ensign Mitsuo Ohta of the 405th Kokutai, and aided by students of the Aeronautical Research Institute at the University of Tokyo, Ohta submitted his plans to the Yokosuka research facility. The Imperial Japanese Navy decided the idea had merit and Yokosuka engineers of the First Naval Air Technical Bureau (Kugisho) created formal blueprints for what was to be the MXY7. The only variant which saw service was the Type 11, and was powered by three Type 4 Mark 1 Model 20 rockets. 150 were built at Yokosuka, and another 600 were built at the Kasumigaura Naval Air Arsenal.Essentially a 1200 kg (2,646 lb) bomb with wooden wings powered by three Type 4 Model 1 Mark 20 solid-fuel rocket motors, the Type 11 achieved great speed but with limited range. This was problematic as it required the slow heavily laden mother aircraft to approach within 20 nautical miles (40 km) of the target, making them very vulnerable to defending fighters.It appears that the operational record of Ohkas used in action includes three ships sunk or damaged beyond repair and three other ships with significant damage. Seven US ships were damaged or sunk by Ohkas throughout the war.Jap Pilots Ride to DEATH on Flying Bombs - Modern Mechanix (Apr, 1933)The current conflict between Japan and China has brought out an amazing revelation of the methods by which Japanese pilots assure air bombs reaching their target by putting a man inside to steer them. Why? Read the reasons in this article, and you’ll have a better understanding of Japanese psychology toward the machines of war.IMAGINE yourself strapped within a hollow chamber inside a huge air bomb, surrounded on all sides by high explosives. In front of you is an airplane type rudder which steers the tail unit of the bomb. Windows in the nose enable you to see ahead. You’re loaded into the bomb, which is placed in its nest under the fuselage of a bombing plane. The bomber takes off, soars above a target—say, an ammunition dump of the enemy. Up above you, the pilot of the plane pulls a lever.Down you go, plunging toward the ground with terrific speed. You see that you aren’t going to strike the ammunition dump, but will land many yards to one side of it. So you twist the control rudder, swerving the bomb’s course. Success! The dump looms up directly below the windows of your bomb. And that is practically the end of things for you.Sounds like the superheated imagining of a Jules Verne, doesn’t it—the sort of absurdity that a sensible man would laugh off as being unheard of, an astounding, amusing impossibility?It’s nothing of the sort. It’s an actual fact of warfare, a method used by Japanese pilots who deem it an honor transcending all others to ride to glory for the mother country. They know that their memory and their families will be forever honored in their homeland.Rumors of the flying bomb death ride have filtered out of the conflict now being waged by the Japanese and Chinese. Necessarily this information has been of a confidential, undercover nature, but not long ago it was given nation-wide publicity by a radio commentator on international affairs.Japanese and MachinesTo make the man-steered bomb a credible actuality, an understanding of the peculiarities of the Japanese character is necessary. And some such understanding may sooner or later be forced upon, the great powers of the world who are all too likely to become involved in the aggression of Japanese militarists in China, where the United States, Great Britain, France, Italy and Germany do much business.In the field of machinery the Japanese mind is at a peculiar disadvantage. They are able to turn out an exact copy of any mechanism that comes into their hands, but the type of mechanical imagination which went into its original creation—which, for want of a better term, is sometimes known as Yankee ingenuity—they are at a loss to duplicate.The simple truth of the matter is that - a man is practically required to steer Japanese bombs to their mark because they haven’t been able to develop the bomb-sighting machinery which makes Uncle Sam’s flyers, for instance, so deadly in their accuracy.THE BAKA BOMB IDEA by me109glen Vue MilitaryPeculiar Oriental PsychologyAs to why Japanese soldiers fight among themselves for the honor of being the bomb pilot who can look forward to being blown to certain oblivion, that’s a matter of psychology not so easy to understand. Patriotism rules the Japanese to an almost fanatical degree, and love of country is so bound up with religion—the emperor being regarded as an incarnate god—that to be blown up in a bomb to further the successes of Nippon becomes something to be desired above all things.When one understands the popularity that hara-kiri, a form of suicide by self-disembowelment, has had among the Japanese for centuries, the national willingness to dive to death in a bomb, or in any other way, becomes credible.Hara-kiri, as formerly practiced, was compulsory upon a noble of the higher class who received a courteously phrased message from the mikado intimating that he must die for some offense of lawbreaking or disloyalty. The suicide, using a jeweled dagger customarily sent by the mikado for performing the act, proceeded in a prescribed ritual. Seated on a dais, surrounded by officials and friends, the suicide plunged the dagger into his stomach below the waist on the left side, drew it slowly across to the right, and turning it, gave a slight cut upward.This compulsory suicide has been abolished, but the idea has such a striking appeal for the Japanese imagination that some 1500 hara-kiris take place annually as a purely voluntary gesture.In the final analysis, the amazing thing is not that the Japanese should succeed in finding pilots for their man-bombs, for volunteers for such a mission of certain death can be found in any army in the world, but that such a weapon should be necessary. It simmers down to the fact, as hinted at above, that the Nipponese are conscious of their inferiority in developing new and fearful weapons of war, and are forced to rely on man-power.A country like the United States would approach the problem of directing bomb flight in an entirely different way. Some method of mechanical control of the bomb would be sought—in fact, the idea of controlling a bomb or gun shell by radio is already being worked on, as described in Modern Mechanix and Inventions some months ago. It will be seen that, entirely aside from making the sacrifice of a man’s life unnecessary, radio control of a bomb is much more accurate and less liable to error through the failure of the human machine in a moment of critical nervous tension.Superiority of American engineering brains over the Oriental variety is well demonstrated in the newest United States army bombing plane, a photograph of which is reproduced in these pages. It is a monoplane of all-metal construction—no wood or fabric to catch fire from incendiary bullets of the enemy—and is so well streamlined, with its landing gear pulled up under its belly, that it can do a top speed of 200 miles an hour, fully loaded with a two ton cargo of bombs. This is 80 miles an hour better than the speed of the Curtiss bomber, a biplane, previously used by the air corps.Features of U. S. BomberA revolving turret to protect the gunner in the nose of the ship is another feature. It diverts the rush of air and makes accurate aiming much easier. At high speeds, the wind stream is so powerful that, in an ordinary ship, it has a tendency to wrench a swivel mounted gun out of the gunner’s control.In connection with the possible need of protecting our country from Pacific aggression, the news that a government expedition has just left for an extensive survey of the Aleutian islands (which constitute the tip of the Alaskan peninsula) is important. A map, reproduced herewith, shows the extremely important location of these islands in their relation to Japan and the Orient.Geologically, these islands are thought to be the sunken peaks of land that once connected the mainland with Asia. Siberia is but a stone’s throw distant, and the northern islands of Japan not much farther away. Since, by a recent bill passed in Congress, the United States has relinquished control of the Philippine islands, we will have no Pacific base of importance other than Hawaii and Guam, which makes the Aleutian chain all the more important in the scheme of national protection.Strategic Importance of IslandsAirplanes are being carried by the expedition and these will make a careful aerial survey of the islands. A weather observation station will probably be established on Tanago or Adak island, and the best suited of the nearby islands will be chosen as a possible base for an airplane field. Harbor facilities will be carefully charted with a view to possible installation of a naval base for ships and submarines. Alaska, of course, is a United States possession which we are free to fortify as we may see fit. An incident of the World War which has just come to light illustrates the ingenuity of the western mind in the world of machines. German engineers designed a mine fitted with clockwork which permitted the device to float in toward English shores when the tide was right. When the tide ebbed, the mine automatically sank to the bottom, where it waited the proper interval and then released itself again to float closer to the shore. The British were unable to figure out how the mines got there.Above article by Ray Holt.Japanese Pilots Ride to DEATH on Flying BOMBSYokosuka MXY-7 OhkaYokosuka MXY7 Ohka [Oka] Japanese Flying Bomb (fiddlersgreen.net)In 1944 a lowly ranked Japanese transport pilot proposed the idea of a rocket-powered aircraft for suicide missions against Allied naval forces. In record time, the Yokosuka MXY7 Ohka ('Cherry Blossom') was developed and accepted for service.Carried aloft by G4M 'Betty' bombers, the Ohkas remained attached until 21 miles off the target, well within range of the carrier group's combat air patrols. On their combat debut, all 16 carrier aircraft were shot down before launching their Ohkas. Of the 750 or so Ohkas built, the vast majority were never launched, being shot down while attached to their carrier aircraft or destroyed or captured on the ground. It is thought that they sank about 15 Allied ships, having minimal effect on the Allied advance on Japan.The Ohka was to have been mass-produced in underground factories, but the war ended before these were completed, one projected version of the rocket bomb, the Ohka 43A, was intended to be catapulted from surface submarines and was to have had folding wings for stowage in deck hangars. The Ohka 43B was basically similar but was designed for the defense of the Japanese homeland and was to have been launched against an invasion fleet from catapults installed in caves. Neither version was built.The Oka Suicide Flying BombIn the course of the Pacific War, the Japanese lost practically all of its warships and aircrafts. They also lost two key commanders, Admiral Yamamoto and his successor Admiral Koga.In late 1943, proposals were made by Japanese Naval Fighter Pilots for special suicide attacks against the United States Naval Forces to stem the might that was falling upon them. These men were concerned over the inferiority of Japanese Naval and Army strength and they had started to consider suicidal-crash dive tactics with their aircraft to counter growing United States Military strength.Naval Ensign Ohta, the designer of the OKA bomb, was one of these men. Their idea was originally refused but as the war grew worse for Japan, support grew for Kamikaze Operations.Captain Jyo, Commander of the Japanese Aircraft carrier "Chiyoda," stated after the Battle of the Philippine Sea in June 1944, "No longer can we hope to sink the numerically superior enemy carriers through ordinary attack methods. I urge the use of special attack units to crash dive their aircraft and I ask to be placed in command of them."The "Chiyoda" was later sunk and so the honor to command the Special Attack Group (Kamikaze Corps) fell upon Admiral Takijiro Ohnishi. In October 1944, he took command of the Japanese First Air Fleet in the Philippines. The first organized Kamikaze operations began with volunteers from the 201st Japanese Naval Air Group. This unit was based at Clark Field, 50 miles north of Manila, Philippine Is. The first attacks were made with conventional Zero Fighter Aircraft with 500 Kilogram bombs attached below the aircraft. For Okinawa another Kamikaze aircraft was chosen, whose origin began the year prior.Many of the Japanese Admirals on the General Staff did not believe the time for such extreme tactics for Kamikaze was at hand. When the Marianas Islands fell, one after the other and each defeat became increasingly worse for Japan, Kamikaze attack plans were put into effect as the only solution.During the summer of 1944, a Japanese Naval Officer Ensign Mitsuo Ota was given permission to draw up plans for a special Kamikaze attack aircraft. Ensign Ota was a Naval Aircraft Transport pilot with little engineering background, however, he applied for and received assistance from the aviation research department of Tokyo University. When the drawings were completed, they were submitted to Yokosuku Naval Depot for approval. The Navy Command approved Ota's design in late 1944 and this aircraft was afterward named "OKA" which is "Cherry Blossom" in Japanese.The OKA was kept very secret, even within high naval circles. Japanese Captain Motoharu Okamura was given command to train the elite pilots of the "OKA Bomb." His attack base was located at Kamiike Air Base just northeast of Tokyo.The OKA Bomb was a small wooden and metal constructed aircraft. It had room pilot and the nose warhead contained 2645 pounds of explosives. The OKA was usually carried under the belly of a twin engine "Betty" Bomber, although other types of twin engine Japanese bombers could be used with modifications. It was attached and partially hung in the bomb bay by one mounting lug and slings fastened under the wing and empennage.The OKA was generally launched 25-50 miles from target. lt's range was determined by the altitude at which it could be released. As air-to-air fighting progressed, two additional rocket motors were fitted, one under each wing, to enable the OKA to pull away from prowling Navy Hellcat Fighters. These rocket units could be fixed singly or simultaneously at the Kamikaze pilot's discretion. The OKA had a conventional pilot stick and rudder bar arrangement.The pilot had at his disposal a selector switch for firing the propulsion rocket charges pull type arming handle for the nose bomb base fuse, a compass, an altimeter, airspeed indicator, rocket temp. gauge and an inclinometer. All control surfaces were dynamically balanced to eliminate flutter at the high speeds the OKA operated. The nose warhead had five fuses, one in the nose and four in the base. The nose fuse was straight impact fuse and was vane armed. Two of the base fuses were straight impact and the other two were of the "all way" type. All four of the base fuses were armed manually by the pilots from the cockpit.'A post and ring sight was mounted on the OKA for aiding the pilot in aiming the OKA at its target. There is no landing gear and the OKA was moved on a special dolly when on the ground. It had a wing span of sixteen feet and five inches and a length of twenty feet. Its loaded weight was 4,718 pounds. It had three Type 4, MK 1, Model 20 solid fuel rocket motors mounted in the tail. The prototype OKA Bomb was completed in September 1944. Flight testing began on October 23, 1944, using a number of OKAs constructed at the Yokosuka Naval Air Depot. The first prototype was a pilot less OKA 11. It was launched from a Mitsubishi G4M "Betty" Bomber, high above Sagami Bay near Tokyo, at an altitude of 13,000 feet. The test trials were successfully completed and production was increased by adding two additional plants into producing the OKA bomb: Fuji Hikok and Chigasaki-seisakusho.The OKA MXY-7 was built as a Training Glider for pilot training. lt differed from the armed OKA 11 primarily in having no rocket powered motor or warhead. A large skid was fitted beneath the fuselage and a smaller one beneath each wing for landing. In order to simulate combat load conditions of the OKA 11, water ballast tanks were fitted at the front and rear of the cockpit. For landing the water was discharged, thereby reducing the weight considerably.The testing of the prototype OKA MXY-7 Training Glider was carried out by a Japanese Naval Man-Pilot Officer Nagoro at Hykurigaharu Air Base. On October 31, 1944, after the test was completed, he reported the flight handling characteristics were very good. Later the water ballast tanks were deleted as being unnecessary. A total of forty-five OKA MXY-7's were built. One example can be seen today in the Air Force Museum at Dayton, Ohio; however, the skid has been removed to make it appear as an OKA 11.The OKA pilot would ride in the mother bomber until the target area was approached. He would then climb through the bomb bay of the mother plane into the cockpit of the OKA.When the enemy position had been made known to the pilot, he would then signal his readiness to the bomber crew. He would pull the release handle and would be on his way in his missile of destruction. Once the release handle was pulled, it became a one-way trip for the pilot. American propaganda during the war stated that the Japanese pilots were locked in their cockpit. This was not true. The pilot would glide the OKA toward the remaining distance to the target area, whereupon after selecting the target would ignite all three rocket motors and crash dive into the target at over 600 miles per hour. Needless to say it was very hard to down this aircraft once the Kamikaze aircraft was in the air under its own power.When the OKA bomb became known it was labeled as the "BAKA BOMB" or "Fool Bomb" and this name prevails to this day. It took a little over six months to train a pilot for the OKA Special Attack Mission. These men were carefully selected from throughout the Navy Air Force and all were well qualified.With the invasion of Okinawa, Japan knew the crushing might of the United States Navy had to be stopped. Fifty OKA 11's were selected to meet this challenge and on the first day of the Okinawa Invasion, four United States carriers were hit and damaged. The U.S.S. Enterprise, Yorktown, Intrepid, and Franklin by OKA Suicide Flying Bombs.On March 21, 1945, United States carriers were again sighted just south of Kyushu. Japanese Admiral Ugaki, 5th Air Fleet Commander, took this opportunity for using OKA 11's from Kanoya Air Base.Kamikaze attack plane Yokosuka MXY7 Ohka OkinawaFighter aircraft protection was assigned but it was felt more fighter aircraft would be needed to protect the slow and vulnerable G4M "Betty" Bomber mother aircraft. The Japanese Navy was well aware of the capabilities of the U.S. Navy's very fine Grumman F6F "Hellcat" fighters.The special attack group consisted of sixteen OKA and eighteen mother planes. The flight leader was Naval Commander Goro Naraka. One of the Kamikaze pilots remarked on this sortie: "We are sixteen warriors manning our aircraft. May our death be as sudden as the shattering of crystal." Only thirty Japanese fighters were available to provide fighter escort protection and with this news, the chance for success in this mission became doubtful. The attack was launched regardless, and at 4 p.m. at a point sixty miles short of the sighted U.S. fleet, fifty Grumman FGF "Hellcats" attacked the OKA bomber force and destroyed the entire group before the deadly OKA bombs could be released.In November 1944, the world's largest aircraft carrier at the time, the gigantic Shinano, left Yokosuka Bay during the darkness of night to transport fifty OKA bombs to the philippine islands. But, as it got under way it was spotted and tracked by a U.S. Naval Submarine and sunk on November 29, 1944, off the Japanese mainland. Thus, the projected use of the OKA in the Philippines was precluded.Special OKA groups of the 721st and 722nd squadrons were based at Kanoya, Miyazaki, Oita, Atsuki and Kamatsu Air Bases. The chief targets for the OKA special attack group lay chiefly at Okinawa and the surrounding waters. Early Kamikaze pilots were replaced by new ones, who in turn were replaced by still newer pilots. Some Cherry Blossoms had fallen, but there were still more to come.The initial landings on Okinawa were met with little enemy opposition, but the fighting became fierce as U. S. forces went to the interior of the island. One of the big surprises to U. S. Technical Air Intelligence men was the capture of six new Japanese OKA." Bombs in caves near Kadena Airfield. These special attack aircrafts had only arrived from Japan a few weeks before the invasion. They were assembled and were ready for use when U. S. Naval fighters hit the airfield and destroyed their mother aircrafts.The Kamikaze Special Attack Corps derived their name after the typhoon which frustrated the Mongolian invasion of Japan in 1280.The man who was given responsibility for the formation of the Kamikaze Corps was Vice Admiral Ohnishi. The success of his organization is attributable to the bond of feeling and purpose which existed between he and his men. The watchword of the Kamikaze was "We die for the great cause of our country." The pilots did not consider they were committing suicide but rather were only doing their job as pilots by inflicting the greatest possible damage upon the enemy.To the Kamikaze pilot, their greatest concern seemed always to have been to make sure that they would hit the target. By comparison, their death to them was a matter of very minor importance. This can be summed up as-There is an old Japanese proverb: "Life is as the weight of a feather compared to one's duty."The Kamikaze attacks shocked the world primarily because of their certain death-self destruction aspects. The Kamikaze inflicted more casualties to the U.S. Fleet off the Okinawa shore than did the bloody hand-to-hand fighting to the invading troops in the long battle ashore.The Kamikaze attacks also did tremendous damage to U.S. ships but it failed to produce the desired results which the Japanese hoped for.It is perhaps hard for the Western mind to accept this idea - a man determined to die in order that he might destroy us in battle.One of the earliest lessons one learns in battle is that courage is a very common human quality. Evidence of this can be seen from U. S. Navy Torpedo Squadron B at the Battle of Midway in June 1942, where all aircraft and pilots were lost save one pilot.But there was a fundamental difference in the heroism of Japanese and U. S. flyers. The Japanese resolutely closed all avenues of hope and escape; the American never did. To the Western mind there must always be that last slim chance of survival, that, though a lot of other men may die, you yourself, somehow, someway, will make it back.The Yokosuka MXY7 Ohka was a great idea as far as rocket planes went. The Japanese built 755 of them by March 1945, and they were all built from non-strategic materials and were incredibly easy to fly. The pilot was to glide them then punch the rockets for a high speed approach to the target. There is no data on the landing characteristics of the Ohka (cherry blossom), for the ones that reached their targets exploded on impact. They were suicide planes, carrying 2,646 pounds of high explosives in the nose.Few actually reached the ships they were intended to hit, however; the launch vehicle, 16 Mitsubishi G4M2e twin-engine Bettys, tended to be destroyed by U.S. fighters before nearing the targets. They still released the Ohka, which usually nosed into the ocean. One did make it to a ship: the destroyer USS Mannert L. Abele, which sunk as a result of a direct hit in April 1945. By then production had ceased on the suicide plane; the Japanese deemed the converted bomber too slow to near the targets.These images are were taken at Smithsonian Air and Space Museum.SpecificationsLength: 20 ftWingspan: 16 ft 8 inHeight: 3 ft 11 inWing area: 65 ft²Loaded weight: 4,720 lbPowerplant: 3× rocketmotors , 587 lbf eachPerformanceMaximum speed: 500 mphRange: 23 miWing loading: 72 lb/ft²Thrust/weight: 0.38Dive speed (3×Rocket motors Full-Boost): 650 mphArmament2,646 lb Ammonal warheadA: The Ohka 11 was armed with a 2645 lb high-explosive warhead in the nose Later versions had smaller warheads.B: The fuselage was a standard aluminum structure, but the wings were made of molded plywood covered in fabric.C: Cockpit instrumentation consisted of only four instruments: a compass, an airspeed indicator, an altimeter and an inclinometer for turn indication.D: The later Model 22 had a turbojet engine with a small auxiliary piston engine acting as a gas generator. The only test flight of the Model 22 ended in an (unintentional) crash.E: Would-be suicide pilots were trained to kill themselves in a training glider version, an example of which is preserved in the US Air Force Museum.F: Known disparagingly by the Allies as the Baka (Fool), the MXY7 was one of the few aircraft actually designed to kill its pilot. Judged against this requirement, it could be considered a success.U.S.S. Bunker Hill suffering the attack of an Yokosuka MXY-7 Ohka.© 1994 - 2018 http://Fiddlersgreen.net. All Rights reserved.

From CDC Official:Recommended Guidance for Extended Use and Limited Reuse of N95 Filtering Facepiece Respirators in Healthcare SettingsBackgroundThis document recommends practices for extended use and limited reuse of NIOSH-certified N95 filtering facepiece respirators (commonly called “N95 respirators”). The recommendations are intended for use by professionals who manage respiratory protection programs in healthcare institutions to protect health care workers from job-related risks of exposure to infectious respiratory illnesses.Supplies of N95 respirators can become depleted during an influenza pandemic (1-3) or wide-spreadoutbreaks of other infectious respiratory illnesses.(4) Existing CDC guidelines recommend a combination of approaches to conserve supplies while safeguarding health care workers in such circumstances. These existing guidelines recommend that health care institutions:Minimize the number of individuals who need to use respiratory protection through the preferential use of engineering and administrative controls;Use alternatives to N95 respirators (e.g., other classes of filtering facepiece respirators, elastomeric half-mask and full facepiece air purifying respirators, powered air purifying respirators) where feasible;Implement practices allowing extended use and/or limited reuse of N95 respirators, when acceptable; andPrioritize the use of N95 respirators for those personnel at the highest risk of contracting or experiencing complications of infection.This document focuses on one of the above strategies, the extended use and limited reuse of N95 respirators only; please consult the CDC or NIOSH website for guidance related to implementing the other recommended approaches for conserving supplies of N95 respirators.There are also non-emergency situations (e.g., close contact with patients with tuberculosis) where N95 respirator reuse has been recommended in healthcare settings and is commonly practiced.(5-9) This document serves to supplement previous guidance on this topic.DefinitionsExtended use refers to the practice of wearing the same N95 respirator for repeated close contact encounters with several patients, without removing the respirator between patient encounters. Extended use may be implemented when multiple patients are infected with the same respiratory pathogen and patients are placed together in dedicated waiting rooms or hospital wards. Extended use has been recommended as an option for conserving respirators during previous respiratory pathogen outbreaks and pandemics.(10, 11)Reuse1 refers to the practice of using the same N95 respirator for multiple encounters with patients but removing it (‘doffing’) after each encounter. The respirator is stored in between encounters to be put on again (‘donned’) prior to the next encounter with a patient. For pathogens in which contact transmission (e.g., fomites) is not a concern, non-emergency reuse has been practiced for decades.(7) For example, for tuberculosis prevention, CDC recommends that a respirator classified as disposable can be reused by the same worker as long as it remains functional2 and is used in accordance with local infection control procedures.(9) Even when N95 respirator reuse is practiced or recommended, restrictions are in place which limit the number of times the same FFR is reused.Thus, N95 respirator reuse is often referred to as “limited reuse”. Limited reuse has been recommended and widely used as an option for conserving respirators during previous respiratory pathogen outbreaks and pandemics.(2, 3, 10-12)ImplementationThe decision to implement policies that permit extended use or limited reuse of N95 respirators should be made by the professionals who manage the institution’s respiratory protection program, in in consultation with their occupational health and infection control departments with input from the state/local public health departments. The decision to implement these practices should be made on a case by case basis taking into account respiratory pathogen characteristics (e.g., routes of transmission, prevalence of disease in the region, infection attack rate, and severity of illness) and local conditions (e.g., number of disposable N95 respirators available, current respirator usage rate, success of other respirator conservation strategies, etc.). Some healthcare facilities may wish to implement extended use and/or limited reuse before respirator shortages are observed, so that adequate supplies are available during times of peak demand. For non-emergency (routine) situations, current CDC recommendations (6, 9) specific to that pathogen should also be consulted.The following sections outline specific steps to guide implementation of these recommendations, minimize the challenges caused by extended use and reuse, and to limit risks that could result from these practices.Respirator Extended Use RecommendationsExtended use is favored over reuse because it is expected to involve less touching of the respirator and therefore less risk of contact transmission. Please see the section on Risks of Extended Use and Reuse of Respirators for more information about contact transmission and other risks involved in these practices.A key consideration for safe extended use is that the respirator must maintain its fit and function. Workers in other industries routinely use N95 respirators for several hours uninterrupted. Experience in these settings indicates that respirators can function within their design specifications for 8 hours of continuous or intermittent use. Some research studies (14, 15) have recruited healthcare workers as test subjects and many of those subjects have successfully worn an N95 respirator at work for several hours before they needed to remove them. Thus, the maximum length of continuous use in non-dusty healthcare workplaces is typically dictated by hygienic concerns (e.g., the respirator was discarded because it became contaminated) or practical considerations (e.g., need to use the restroom, meal breaks, etc.), rather than a pre-determined number of hours.If extended use of N95 respirators is permitted, respiratory protection program administrators should ensure adherence to administrative and engineering controls to limit potential N95 respirator surface contamination (e.g., use of barriers to prevent droplet spray contamination) and consider additional training and reminders (e.g., posters) for staff to reinforce the need to minimize unnecessary contact with the respirator surface, strict adherence to hand hygiene practices, and proper Personal Protective Equipment (PPE) donning and doffing technique.(16) Healthcare facilities should develop clearly written procedures to advise staff to take the following steps to reduce contact transmission after donning:Discard N95 respirators following use during aerosol generating procedures.Discard N95 respirators contaminated with blood, respiratory or nasal secretions, or other bodily fluids from patients.Discard N95 respirators following close contact with, or exit from, the care area of any patient co-infected with an infectious disease requiring contact precautions.Consider use of a cleanable face shield (preferred3) over an N95 respirator and/or other steps (e.g., masking patients, use of engineering controls) to reduce surface contamination.Perform hand hygiene with soap and water or an alcohol-based hand sanitizer before and after touching or adjusting the respirator (if necessary for comfort or to maintain fit).Extended use alone is unlikely to degrade respiratory protection. However, healthcare facilities should develop clearly written procedures to advise staff to:Discard any respirator that is obviously damaged or becomes hard to breathe through.Respirator Reuse RecommendationsThere is no way of determining the maximum possible number of safe reuses for an N95 respirator as a generic number to be applied in all cases. Safe N95 reuse is affected by a number of variables that impact respirator function and contamination over time.(18, 19) However, manufacturers of N95 respirators may have specific guidance regarding reuse of their product.The recommendations below are designed to provide practical advice so that N95 respirators are discarded before they become a significant risk for contact transmission or their functionality is reduced.If reuse of N95 respirators is permitted, respiratory protection program administrators should ensure adherence to administrative and engineering controls to limit potential N95 respirator surface contamination (e.g., use of barriers to prevent droplet spray contamination) and consider additional training and/or reminders (e.g., posters) for staff to reinforce the need to minimize unnecessary contact with the respirator surface, strict adherence to hand hygiene practices, and proper PPE donning and doffing technique, including physical inspection and performing a user seal check.(16) Healthcare facilities should develop clearly written procedures to advise staff to take the following steps to reduce contact transmission:Discard N95 respirators following use during aerosol generating procedures.Discard N95 respirators contaminated with blood, respiratory or nasal secretions, or other bodily fluids from patients.Discard N95 respirators following close contact with any patient co-infected with an infectious disease requiring contact precautions.Consider use of a cleanable face shield (preferred3) over an N95 respirator and/or other steps (e.g., masking patients, use of engineering controls), when feasible to reduce surface contamination of the respirator.Hang used respirators in a designated storage area or keep them in a clean, breathable container such as a paper bag between uses. To minimize potential cross-contamination, store respirators so that they do not touch each other and the person using the respirator is clearly identified. Storage containers should be disposed of or cleaned regularly.Clean hands with soap and water or an alcohol-based hand sanitizer before and after touching or adjusting the respirator (if necessary for comfort or to maintain fit).Avoid touching the inside of the respirator. If inadvertent contact is made with the inside of the respirator, discard the respirator and perform hand hygiene as described above.Use a pair of clean (non-sterile) gloves when donning a used N95 respirator and performing a user seal check. Discard gloves after the N95 respirator is donned and any adjustments are made to ensure the respirator is sitting comfortably on your face with a good seal.To reduce the chances of decreased protection caused by a loss of respirator functionality, respiratory protection program managers should consult with the respirator manufacturer regarding the maximum number of donnings or uses they recommend for the N95 respirator model(s) used in that facility. If no manufacturer guidance is available, preliminary data(19, 20) suggests limiting the number of reuses to no more than five uses per device to ensure an adequate safety margin. Management should consider additional training and/or reminders for users to reinforce the need for proper respirator donning techniques including inspection of the device for physical damage (e.g., Are the straps stretched out so much that they no longer provide enough tension for the respirator to seal to the face?, Is the nosepiece or other fit enhancements broken?, etc.). Healthcare facilities should provide staff clearly written procedures to:Follow the manufacturer’s user instructions, including conducting a user seal check.Follow the employer’s maximum number of donnings (or up to five if the manufacturer does not provide a recommendation) and recommended inspection procedures.Discard any respirator that is obviously damaged or becomes hard to breathe through.Pack or store respirators between uses so that they do not become damaged or deformed.Secondary exposures can occur from respirator reuse if respirators are shared among users and at least one of the users is infectious (symptomatic or asymptomatic). Thus, N95 respirators must only be used by a single wearer. To prevent inadvertent sharing of respirators, healthcare facilities should develop clearly written procedures to inform users to:Label containers used for storing respirators or label the respirator itself (e.g., on the straps(11)) between uses with the user’s name to reduce accidental usage of another person’s respirator.Risks of Extended Use and Reuse of RespiratorsAlthough extended use and reuse of respirators have the potential benefit of conserving limited supplies of disposable N95 respirators, concerns about these practices have been raised. Some devices have not been FDA-cleared for reuse(21). Some manufacturers’ product user instructions recommend discard after each use (i.e., “for single use only”), while others allow reuse if permitted by infection control policy of the facility.(19) The most significant risk is of contact transmission from touching the surface of the contaminated respirator. One study found that nurses averaged 25 touches per shift to their face, eyes, or N95 respirator during extended use.(15)Contact transmission occurs through direct contact with others as well as through indirect contact by touching and contaminating surfaces that are then touched by other people.Respiratory pathogens on the respirator surface can potentially be transferred by touch to the wearer’s hands and thus risk causing infection through subsequent touching of the mucous membranes of the face (i.e., self-inoculation). While studies have shown that some respiratory pathogens (22-24) remain infectious on respirator surfaces for extended periods of time, in microbial transfer (25-27) and reaerosolization studies (28-32) more than ~99.8% have remained trapped on the respirator after handling or following simulated cough or sneeze.Respirators might also become contaminated with other pathogens acquired from patients who are co-infected with common healthcare pathogens that have prolonged environmental survival (e.g., methicillin-resistant Staphylococcus aureas, vancomycin-resistant enterococci, Clostridium difficile, norovirus, etc.). These organisms could then contaminate the hands of the wearer, and in turn be transmitted via self-inoculation or to others via direct or indirect contact transmission.The risks of contact transmission when implementing extended use and reuse can be affected by the types of medical procedures being performed and the use of effective engineering and administrative controls, which affect how much a respirator becomes contaminated by droplet sprays or deposition of aerosolized particles. For example, aerosol generating medical procedures such as bronchoscopies, sputum induction, or endotracheal intubation, are likely to cause higher levels of respirator surface contamination, while source control of patients (e.g. asking patients to wear facemasks), use of a face shield over the disposable N95 respirator, or use of engineering controls such as local exhaust ventilation are likely to reduce the levels of respirator surface contamination.(18)While contact transmission caused by touching a contaminated respirator has been identified as the primary hazard of extended use and reuse of respirators, other concerns have been assessed, such as a reduction in the respirator’s ability to protect the wearer caused by rough handling or excessive reuse.(19, 20) Extended use can cause additional discomfort to wearers from wearing the respirator longer than usual.(14, 15) However, this practice should be tolerable and should not be a health risk to medically cleared respirator users.(19)ReferencesMurray, M., J. 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Kennedy: Particle release from respirators, part I: determination of the effect of particle size, drop height, and load. Journal of Occupational and Environmental Hygiene 8(1): 1-9 (2011).Kennedy, N.J., and W.C. Hinds: Release of simulated anthrax particles from disposable respirators. Journal of Occupational and Environmental Hygiene1(1): 7-10 (2004).Qian, Y., K. Willeke, S.A. Grinshpun, and J. Donnelly: Performance of N95 respirators: reaerosolization of bacteria and solid particles. American Industrial Hygiene Association Journal 58(12): 876-880 (1997).Willeke, K., and Y. Qian: Tuberculosis control through respirator wear: performance of National Institute for Occupational Safety and Health-regulated respirators. American Journal of Infection Control 26(2): 139-142 (1998).