Blue Marble Next Generation

Blue Marble Next Generation : Feature Articles.

This spectacular “blue marble” image is the most detailed true-color image of the entire Earth to date. Using a collection of satellite-based observations, scientists and visualizers stitched together months of observations of the land surface, oceans, sea ice, and clouds into a seamless, true-color mosaic of every square kilometer (.386 square mile) of our planet.

These are from the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument on the Terra satellite, flying in a 700-km orbit. I think some of the other Blue Marble imagery came from the Aqua satellite. Neat stuff.

5 A-10 squadrons to be cut – Air Force News | News from Afghanistan & Iraq – Air Force Times

The A-10 Thunderbolt II provides the type of close-air support that ground-pounders love and the Taliban dread. Although the A-10s are workhorses in the war on terrorism, the Air Force in its new budget request is planning to get rid of five squadrons.

As part of the Defense Department’s efforts to trim close to $500 billion in spending over the next decade, defense officials said Friday that the service intends to cut five A-10 tactical squadrons and two other squadrons as well.

The Thunderbolt squadrons to be stood down encompass one active-duty, one Reserve and three National Guard units. The remaining two squadrons disappearing are a Guard F-16 tactical unit and an F-15 training squadron.

via 5 A-10 squadrons to be cut – Air Force News | News from Afghanistan & Iraq – Air Force Times.

How many times now is this? The Air Force has hated the A-10 since the day they started the program. They’ve tried to kill it more than once, and reality keeps intruding.  But sooner or later, they’ll kill of one of the most successful platforms ever made.


2011 Army Year in Photos

2011 Army Year in Photos.

Click on the months – there’s more than one photo per month.

Pvt. Stephen Justice, an infantryman from Haverhill, Mass. with Company C, 3/172nd Infantry Regiment (Mountain) of the New Hampshire National Guard, acts as an assistant gunner and feeds rounds through a M240B machine gun, while the gunner, Spc. Trevor Seaton, an infantryman from Rochester, N.H., fires with the weapon at Fort Devens, Mass.

This one is for Swamp Heathen #1.

Spc. Devon Boxa, a member of Company B, 7th Battalion, 158th Aviation Regiment, looks out the back door of a CH-47D Chinook helicopter as another Chinook follows. The helicopters were flying from Kabul to Jalalabad, Afghanistan, Dec. 17.

Soldiers from the 2nd Battalion, 8th Field Artillery Regiment, 1st Stryker Brigade Combat Team, 25th Infantry Division, currently deployed to the U.S. Army's National Training Center in Fort Irwin, Calif., fire the M777 A2 Howitzer,

Occupy D.C.’s Tent of Dreams

The big news today in the DC Metro area was not from Capitol Hill or the White House. Rather it came from McPherson Square.  After months and months, the Park Service Police ordered the protest movement out…. well sort of.


I never realized that “camping” was enshrined in the First Amendment.  Go figure.

So the Occupy DC protesters decided to up the ante:

Around mid-day this “Tent of Dreams” went up around the statue of General McPherson.

Protesters put up the tent while climbing and crawling over the statue. In the background were remarks like, “Let us sleep, so we can dream!”

So after a morning of anticipation, the protesters remain… along with the squalor.

But there is perhaps an interesting object lesson with the placement of that “big tent of dreams”

No matter which political side is protesting, they are only able to voice their opinions because our Armed Forces have done a good job protecting this country.  Our freedoms exist because men and women in uniform are willing to offer their backs, their blood, their sweet, and if necessary their lives, when called upon.  Most Americans can sleep safely tonight and, among other things, dream, because a small number (less than 1%) are willing to sacrifice to support those freedoms.

So there’s General McPherson – holding up that “Tent of Dreams.”

War News Updates: So Much For A 313 Ship Navy

UPDATED: Budget Cuts 8 JHSVs; Two LCS; Two LSDs Retire Early; 1 Virginia Sub Slips Past FYDP; Analyst Says Retirements AND Cuts Mean Service Won’t ‘Ever’ Hit 313 Goal

WASHINGTON: The Navy plans to cut a total of 16 ships from its five-year budget, reducing the number of ships funded in fiscal 2013 by three, from 13 down to 10.

Most of these ships are expected to be the Joint High Speed Vessel, built for both the Navy and the Army, and other support ships. Several well informed analysts told me they do not expect the Navy to cut warships or submarines if it can possibly avoid that.

via War News Updates: So Much For A 313 Ship Navy.

Navy shipbuilding is a complete mess, and most of the problems are the Navy’s fault, not this administration’s.

I notice the big cut is in the Joint High Speed Vessel program. The JHSV is a vessel designed to provide transport to Army and Marine equipment over intratheater ranges.  Oddly, it’s been a reasonably successful program to date.

The “Joint” part of the name came because both the Army and the Navy were going to buy them. A while back, the Navy balked and said they would buy them, and the Army didn’t need to. Just like the C-27 program, just as soon as they got control of an Army program, they brought out the long knives.

KC-135 Overpressure

Seeing that bit on the E-8 JSTARS overpressurizing a fuel tank in flight reminded me of another overpressure incident, this time a catastrophic failure. Fortunately, this one happened on the ground.

Doing a depot level maintenance on the bird, a civilian contractor was testing the jet to see if the cabin was properly sealed to maintain pressure. He plugged the relief valves, and started pumping in air. His pressure gauge was home-made, and he failed to note that it had in fact gone all the way around, and was on its second trip around the dial. Jets are built to take a good deal of pressure differential, but not that much. The fuselage failed completely.


Artillery Evolutions: Counter Battery Fire with the 4.7-inch Gun

As mentioned earlier, when the U.S. expanded the field artillery arm to support American Expeditionary Force (A.E.F.) going to France in 1917, planners saw the need for a medium caliber gun to provide counter-battery fire.   Unlike the other artillery types, the Americans had a weapon on hand to fill this need – the Model 1906 4.7-inch Field Gun.

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Well Restored M1906 4.7-inch Field Gun

The Ordnance Department developed the M1906 4.7-inch Field Gun in the decade before World War I.   The Army had sixty of these guns on hand when the U.S. declared war in 1917.  These were among the few American designed guns to see service in France during the war.

Overall the gun reflected conventional design thoughts.  The gun itself was of built up composition with a jacket extending beyond the breech. The jacket attached to a recoil lug.

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Rear of gun showing recoil lug, rods, and cylinders

The gun tube sat upon a cradle with two cylinders underneath housing the long-recoil, hydro-spring system.

The service manual described the recoil action:

The gun moves to the rear 70 inches on the cradle ways, carrying with it the piston rod, spring rods, and spring-rod yoke and compressing the counter-recoil springs.  As the recoil cylinder remains stationary the oil behind the piston must pass to its forward side.  The energy of the recoil of the gun is absorbed by the resistance which the oil offers to being forced through small openings past the piston and by the resistance of the counter-recoil springs.  The energy stored up by the springs returns the gun to its firing position.  This return movement is eased and regulated by the counter-recoil buffer.  The piston-rod pull and spring resistance are transmitted to the carriage, but owing to its weight and the resistance opposed to the trail spade by the earth the carriage remains stationary.

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Trail spade in "up" or traveling position
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Spade in the "down" position - note maneuvering spikes

The breech was a standard interrupted screw with four flats.  A handle swung from left to right, rotating the block, in one continuous pull.  An extractor ejected the empty casing.

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Partly Open Breechblock

Although the gun could fire out to 11,000 yards at 25° elevation, the carriage restricted elevation to 15° and 7,500 yards with a 60 pound high explosive shell.  Traverse was just under 8°, constraining the arc of fire.  But the sighting system borrowed from the successful setup on the M1903 3-inch gun. The gun fired a common high explosive shell containing 3.36 pounds of TNT.

The shrapnel shell contained 711 half-inch steel balls.

In addition the Army fielded gas projectiles during the war.  All rounds for the 4.7-inch gun were fixed, meaning attached to the brass cartridge case, enabling a relatively high rate of fire.

Like the smaller divisional guns, the 4.7-inch gun’s box-trail carriage used a two wheel limber for movement.  With the limber the gun weighed 9,800 pounds, requiring an eight horse team.  This is one reason the U.S. Army set its eye on mechanical prime movers.

At the start of the war, the Army ordered new production batches of the M1906 in order to fill the anticipated need.  As we have seen with the lighter field guns, the Production Board spread the manufacture of the gun out by components.  Rock Island Arsenal, Studebaker Corporation, and Walter Scott Company produced gun carriages to include the recoil system;  American Car & Foundry Company and Maxwell Motor Company produced the limbers;  Northwestern Gun Company and Watervliet Arsenal produced the guns themselves.  In addition American Car & Foundry Company and Ford Motor Company produced caissons.  All told the Army ordered around 750 complete guns.

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Muzzle markings indicating Watervliet manufacture

A well established product entering mass production – nothing to worry about right?  Well three issues (I won’t say problems) arose which limited the 4.7-inch gun’s use.  First, given the desire to remain compatible with French ammunition stocks, planners suggested re-lining the gun to that nation’s 120mm round.  On its face, this sounded like a simple change of millimeters.  However the French 120mm system dated to the 1880s and was quickly departing that nation’s inventory.  Some historians have cited this issue as causing major delays.  I’ve yet to see documentation proving this was more than a paper project anyway.  The companies listed above were already working on 4.7-inch patterns, and the distraction was minimal in my opinion.

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Front View of M1906

The second issue was also ammunition related.  The 4.7-inch was supposed to fire counter-battery missions against German divisional guns.  The 4.7-inch could counter the standard German 7.7cm FK 96 n.A., which ranged only to 6,000 yards.  But the newer 7.7cm FK16 then arriving at the front had a 10,000 yard range, effectively negating the 4.7-inch as a counter-battery gun.  The solution was to adopt a lighter 45 pound shell for the 4.7-inch, allowing for 8,700 yards at 15°.  Furthermore, the Army standardized the practice of “digging in” the trail to allow the 4.7-inch gun to launch shells to its maximum range of 11,000 yards.  Although that required more preparation by the gun crew.  The ultimate solution was a split trail to allow greater on carriage elevation.  Prototypes just such a mounting were at the test ranges as the war ended.

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M1906 showing solid box trail of the carriage, which limited elevation

The most important issue facing mass production of the gun was the gun tube forgings.  Because of the different diameters between the muzzle and breech, manufacturers had difficulty in the heat treatment of the steel jackets.  With a production bottleneck emerging, the Production Board ordered gun tube jackets produced by Edgewater Steel Company in Pittsburgh.  The jackets went to another company on the other side of Pittsburg for machining.  From there the jackets went back to Edgewater for heat treatment. From there the jacket went to the gun-maker who was assembling the other components.

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M1906 - breech and rear of gun

Sounds inefficient, right?  The eventual solution was a redesigned jacket, separate breech ring attaching to the recoil lugs.  However the redesign was too late for the war effort.  With the production bottleneck, only sixteen new production 4.7-inch guns joined forty-eight pre-war examples in France.

While the board sorted out production issues, the Army turned to alternatives.  From the seacoast artillery came twenty-eight 5-inch and ninety-five 6-inch guns.  The Navy contributed forty-six 6-inch guns of various models.  And the firm of Francis Bannerman & Son (a major military surplus dealer of the era) offered thirty 6-inch guns of 30 calibers.  While working gun tubes, these guns lacked field carriages and required other adaptations before issue to the field.  By mid-1918 the Army had the twenty-eight 5-inch gun outfits weighing some 12 tons, but which could fire a shell nine miles.  A similar adaptation for 6-inch guns weighed 21 tons and ranged ten miles.  None of these outfits were worth shipping to the war zone.

Ultimately the solution for the A.E.F., as with the divisional guns, was foreign supplies.   Among the foreign types supplied to the A.E.F. was the British 60-pdr (5-inch) Field Gun in both Mark I and II variety.  Weighing even more than the American 4.7-inch, this beast needed a Holt Tractor to move around the battlefield.  American corps artillery also received quantities of the French 155mm Grande Puissance Filloux (GPF) mle 1917.  But I will save detailed discussion of that piece for another post.

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60-pdr Mark I

In retrospect, the 4.7-inch gun was another sad story in American procurement.  A sound design with much promise, the 4.7-inch was not adapted for mass production.  But the Ordnance Department certainly heeded this lesson and applied it to inter-war design.  In the next war, the US Army would not rely upon foreign cannons.