A Russian was behind the stealth revolution

Raul Colon

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By Raul Colon

On a clear August morning in 1979, in the Nevada desert, a detachment of United States Marines armed with the newest generation ground to air missile system on the U.S. arsenal, the vaunted HAWK, tried to score a hit against a new bird. The new air defense system utilized by the Marines was so sophisticated that it could detect flak of incoming hawks with only their thermal imagery.

In order to make the exercise more intriguing, the people who designed and developed the new plane gave the detachment the exact incoming fly pattern of the airplane. Where it was coming and where it was headed. With this information, the Marines just needed to point the missile system toward the incoming direction of the plane, and the HAWK would arm itself and destroy the looming threat.

At precisely eight o’clock in the morning, the prototype of what was to become the world’s first true stealth plane, the F-117 Nighthawk Fighter-Bomber, appeared over the sunny skies of the Nevada desert. Completely undetected by the world’s most sophisticated anti-aircraft missile system. It was an amazing triumph of designing engineering.

The real truth about the journey from advanced conventional jet designed aircraft to complete stealth was one with many turns.

Big triumphs and even bigger failures that originated back in the mid 1930s and progressed in an obscure form for the next forty years. That’s until the U.S. Air Force considered the possibility of deploying bombers that were hard to see in radar to strike at the Soviet Union, a bombing platform that could penetrate the most densely designed anti-aircraft system in history.

After the Arab-Israeli War of 1973, and after seeing the casualties list of Israeli warplanes downed by Soviet-made surface-to-air missiles, the U.S. military started a crash course in the feasibility of a bomber design which would be invisible to the current and next generation radar systems. The military placed out a request for the design of a radical new plane. At the end of the summation process, the legendary Lockheed’s Skunk Works, the developers of the famous U-2 spy plane and the world’s first near stealthy airplane, the SR-71 Blackbird; was handed the assignment of designing, developing and producing a completely stealthy plane.

After years of top secret research in the design of the shape of the airplane, Skunk Works was at an impasse. The mathematics of stealth fuselage design did not matched with the reality on the field. They needed a new approach. This was delivered by a once obscure radar expert at Lockheed, Denys Overholser.

The reclusive Overholser put forward to the design team an even more obscure paper, wrote in the mid-to-late 1960s by a Russian mathematician. Pyotr Ufimtsev, who was a top scientist at the Moscow Institute of Radio Engineering. The paper he wrote: Method of Edge Waves in the Physical Theory of Diffraction was fully loaded with mathematics equations as well as scientist terms and phrases that its translation from Russian to English took well over seven years after it first surfaced in the West.

After carefully reading and deciphering the almost forty page document, the design team realized what they had in their hands: the breakthrough they needed. The most important section of the study was at the end of the paper. That part was a revisit of an early study produced by a Scottish physicist, Dr. James Maxwell and later remade with new data by the brilliant German electromagnetic expert, Arnold Somerfeld.

Their calculations almost completely predicted the way that a specific geometric configuration would reflect electromagnetic radiation. The paper raw information was primarily used in the design of computer software to be implemented in the collection of radar signature data from various wings and fuselage shapes.

This data was put to great use in the upcoming development of the airplane wings and main fuselage. The study opened a new door to understanding shapes and their importance in the development of a truly stealthy aircraft.

With the data obtained as a direct result of computer system experimentation and, of the Ufimtsev’s paper information, Skunk Works was able to accurately calculate the radar cross section of any surface. This gave the design team the final data needed to go forward with the ultimate design of this amazing aircraft, the F-117 fighter-bomber.

The data also served as the bases for America’s newest generation of stealth aircraft, the F-22 Raptor.

Puerto Rican airports struggling with charter flights

Raul Colon

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By Raul Colon
rcolonfrias@yahoo.com

Puerto Rico is one of the business air destinations in the Caribbean as its serves more than 200 daily passenger flights out of one international and two regional airports.
For local officials, that number should easily be doubled if more charter flights use the regional facilities as staging centers.

But despite massive investments in infrastructure and marketing promotions, the facilities have yet to receive a single charter flight. The problem is puzzling at one of the newest facilities in Puerto Rico.

The potential of the Rafael Hernandez Airport in Aguadilla, located in the northwestern part of the island, has not been fully exploited even after the Puerto Rican government invested millions of dollars in making it an attractive destination.
The main problem with the regional facility is the lack of charter flights, which have been absent from the airport despite a 2008 law which provide a 50 percent discount on air operations to any company that implement that type of service.

“It’s a puzzling the situation. The government has invested resources in promoting this type of flight operation in order to stimulate the Portal del Sol Tourism District and we need to see the results of this investment, especially in this tough economic time,” said Sofia Estevez, the Tourism Company’s Sub-director.

According to the executive, the responsibility of promoting this kind of industry rest on the shoulders of the Corporation for the Economic Development of the Western Region (IDEO by its Spanish acronym), because it’s the only organization with the authority to promote and develop charter flights to the airport.

“IDEO have not presented many promotional packages to investors. That’s the truth. But recently the corporation signed a deal that would provide the airport with its first charter flight by March of 2011,” she said.

Estevez also mentioned that the deal, which IDEO has already committee $1.4 million of its own resources in price reduction and promotion cost, involves a Spanish company and could serve as the gateway for future business.

“If this IDEO program is successful, we can see a booming industry flourishing at the Aguadilla airport. That would produce more jobs to the region and stimulate the island’s overall profile,” Estevez added.

Since 2003, the Puerto Rico Ports Authority has invested millions of dollars in renovating and upgrading the almost 60 year old airport, including the improvement to the 12,000 feet long runway.

According to the Airports General Manager, Arnaldo Deleo, when the government enacted Law 67, known as the Law for the Incentive Programs to Charter Flights at the Rafael Hernandez Airport, in May 2008, it was with idea of producing a constant flow of fights to the area, but despite the incentives presented by the law, no passenger charter have landed at the facility.
“We have invested heavily in the airport to upgrade its facilities. With have a 60 sq/ft terminal waiting for people to use and we hope that once the charter industry take off, we will need to add space,” Deleo said.

Among the incentives granted by Law 67 was a 50 percent reduction in take-off and landing operations as well as matching fund program when a company provides a regular scheduled flight program.

The Aguadilla Airport is currently use by discount airliners such as Jet Blue, Continental Air and Spirit, which provides the customers with six combine daily flights, most of them to Orlando, Fort Lauderdale and New York.

In 2009 the facility moved 500,000 passengers.

Peacemaker’s Global Mission

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By Raul Colon
rcolonfrias@yahoo.com

Conceived during the waning moments of the Second World War as the world’s first true intercontinental bomber, the amazing Convair’s B-36 Peacemaker would go on to have a relative tumultuous short operational life span. Since its conception in late 1941 through its maiden flight on August 8th, 1946, the B-36 seemed to be always on the brink of cancellation. Six times between 1943 and 1945, the Pentagon and Congress tried to shut down the entire program.

At the heart of the discussion was the feasibility of mass produce a large piston-powered platform in light of the rapid development of the jet engine and the possibilities it offered. Clouding even more the issue was a bitter inter-service battle between the newest member of the Pentagon, the Air Force, and the most revered one, the Navy, for control of America’s nuclear deterrence arsenal. In the end, no amount of controversy or Congressional investigations (there were 5 officials ones between 1943 through 1946) managed to stop the program.

The B-36 went on to serve on the front lines but for only 10 years, four of them on active operational status. A pale figure when compared with its replacement, the venerable B-52, which still remains is the US main heavy bomber platform more than five decades since its development. But despite this apparently overwhelming argument against the operational capability of the Peacemaker, the plane did something few others managed. It pushed the limits of technology during its active run. In a nutshell, the Peacemaker became a technology test bed.

Several of these state-of-the-art activities performed by the B-36 are commonly know. Its role as America’s first and only nuclear powered aircraft has been well cover for the past two decades. But others aspects had not been that well covered. One of those was Project Global Flight.

In the spring of 1945, one full year before the bomber were to take to the air for the first time, Convair top officials were so impressed by the Peacemaker’s projected long range profile, that they decided to plan an around-the-world marketing flight. Two full years after the initial interest and after relative small investment on the project, the company abandoned the idea without much fan fare.

On a clear January 1947 (6th) morning and in front of small group of reporters and Air Force officials , Convair revealed the extent of Project Global Flight’s characteristics. The program called for a modified B-36, stripped of all its amour plating, armament, antenna and radomes. The sighting blister would also have been removed. The radio operator, bombardier and gunners would have stayed home for the adventure. Without the gunners there would haven’t a need for guns, so all firing systems were schedule to be decommissioned as would the instrument panels and forward compartment carpeting. The only parts of the interior expected to survive the stripping, albeit in a modified state, were the gallery and crew bunks.

All the modifications would have saved an estimated 5,000 pounds of overall take-off weight. On top of that, the ‘new’ Peacemaker was to be fitted with six new, experimental flexible fuel cells installed on the wing structure. Four adjacent bomb bay fuel tanks were to be installed on the lower air frame section. The last planned alteration propose was the housing on bomb bay door number 4 of four Aerojet (4,000 pounds of thrust) jet assisted take-off (JATO) bottles for fast takeoff operations.

The final plane profiled for this over modified B-36 stated an operational range of 15,075 nautical miles at an average cruising speed of 210 mph. Accordingly to Convair’s press release, Global Flight would have taken off from Idlewild Airport in New York. Following its departure, the massive bomber would proceed with a circle route over Scotland, Germany, the Black Sea, the Soviet Union, Japan, the Aleutian Island in the Pacific Ocean, until it reached Vancouver Island on the Canadian Pacific coast. From then, the aircraft was set to move southward until reaching Forth Worth, Texas, its final destination point.

In the end, this projected flight path, along with the substantial modifications planned for the B-36 in order to completed, were never performed. Reasons for the cancellation varies from account to account (budgetary issues, serviceable airframes at the time and the flight over Soviet Russia are the most commonly use excuses), but the fact that the project faced so many uncertainties in its developmental stages probably doomed the idea.@

Jane’s Aircraft Recognition Guide, Gunter Endres and Mike Gething, HarperCollins 2002

US Air Force: A complete History, Lieutenant Colonel Dik Alan Daso, Hugh Lauter Levin and Associates 2006

Concept Aircraft: prototypes, X-planes, and Experimental Aircraft, Jim Winchester, Thunder Bay Press 2005

Broken Arrows: The B-36 Log

Raul Colon

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By Raul Colon
rcolonfrias@yahoo.com

The B-36 Peacemaker was one of the largest bombers ever to take to the air. Its story is unique in American aviation history. Conceived during the final days of the Second World War as the first true intercontinental bombing platform, the Convair Corporation biggest program endured a tumults short life span despite huge investments. Develop as a purely deterrence weapon, the massive plane barely booked on the United States Air Force’s active arsenal ten years. At a cost of just under 300 million dollars, the B-36 would go down in the record books as one the most expensive aviation program of all time.

Despite it, the B-36 achieved its mission profile with astonish success. During the four years the Pacemaker was assigned full operational status, no major incident erupted between East and West. But by 1955, the Pentagon decided that its ‘ultimate bomber’ could not longer be expected to penetrate the ever more sophisticated Russian air defense system, thus the decision to axe the entire program was made. Delays in the development of the B-52 project extended the life of several Pacemaker airframes well into the early 1960s.

Now, almost five decades since its conception, a downfall of details regarding this amazing piece of engineer is becoming available. From its traditional role as the ultimate heavy bomber platform, to its position as America’s first and only true nuclear powered plane, the B-36 has seen it all, including the active deployment of nuclear weapons.

The United States Department of Defense (DoD) has several terms to address a number of nuclear weapon incidents or mishaps. They are stated on the Nuclear Weapon Accident DoD Directive 5230.16. The incidents involving an un-sanctioned release of a nuclear ordinance includes the accidental or unauthorized launching of a weapon, an unauthorized nuclear detonation, the non-nuclear burning of an atomic warhead or one of its components, radioactive contamination and the jettison of a nuclear payload due to accidental causes.

DoD utilized several terms and definitions to classify an incident involving a peacetime atomic weapon deployment. They are as follow:

• Broken Arrow: Term that identify an accident involving a nuclear payload.
• Bent Spear: Term that identifies a significant incident involving a nuclear weapon.
• Empty Quiver: Term use to report the seizure or loss of a nuclear weapon.
• Faded Giant: Term involving a nuclear reactor or radiological incident.

On a cloudy April afternoon in 1981, the DoD and the US Department of Energy, released to a waiting world its once top-secret Narrative Summaries of Accidents Involving US Nuclear Weapons: 1950 to 1980. In a gripping and detailing matter, the report described thirty two (32) incidents involving an atomic warhead releases during those three decades. Of that number only two (2) involved B-36 operations.

The first one occurred over the Canadian Pacific Ocean coast, near British Columbia. On February 14th 1950, a B-36B (tail number 44-92075), member of the 7th Bomb Wing stationed out of Eielson Air Force Base, Alaska, was on a routine, cross continent simulated combat flight pattern from Eielson to Carswell AFB, Texas when, six hours into its profile, the massive bomber began developed serious engine problems that forced the crew to shut down three of its power plant.

Flying at 12,000 feet with icing conditions forming on its wing structures and with half of its engines out of commission, 44-92075 commenced experimented problems maintain level flight. Under those strenuous conditions, the pilot decided to turn the big bomber away from land and towards the relative safeness of the ocean in order to drop its nuclear ordinance, an Mk 4, Fat Man-type of system, over open waters. Release of the weapon occurred from 8,000 feet. At around 3,800 feet, the altitude on which the weapon’s detonator was pre-set, the high explosive (HE) on the warhead detonated causing a bright flash followed by a robust sound and a shock wave. After release, the aircraft turned south east, towards Princess Royal Island where the crew of 17 bailed out, just one mile outside Island’s coastline. Two days later, the entire wreckage of the plane washed up on Vancouver Island.

Incident No. 2 occurred almost seven years later. Not as detailed as the previous deployment, the report did relates the story of a B-36A ferrying a Mk 17 nuclear bomb from Biggs, AFB in Texas, to Kirtland AFB, New Mexico. On May 22 1957, this particular Pacemaker (no tail number posted on the incident memo) took off from Biggs for its mission envelop. At exactly 11:50 am Mountain Standard Time and while on approach to Kirtland at an altitude of 1,700 feet, the aircraft’s bomb bay door began to gave way releasing the weapon, along with the entire bay structure two minutes later 4.6 miles south of Kirtland’s control tower. The weapon’s parachute mechanism open, but due to the low operational ceiling, it did not completely retarded.

The HE material inside the Mk 17 detonated on impact. The explosion completely destroyed the weapon and left a gapping crater of 12 feet deep and 25 in overall diameter. Such was the violence of the detonation that the Armed Forces Special Weapons Program, the assessment unit assigned the investigation of the accident, found debris fields as far as a mile outside the contact zone. The final incident report blamed the crewman who removed the weapon’s firing pin (a procedure use to secure the ordinance before final bomb run) with snagging a piece of his cloth against the bomb’s parachute release wire for its partial deployment.

German Airships at the outbreak of War 1914

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rcolonfrias@yahoo.com

“Nobody said it will be easy, but I think that this (bombing) campaign can shorter the ground war to a minimum. In fact, there’s a good enough chance that Britain’s public would rise and force its government to the negotiating table”, said a boastful Paul Behncke, Deputy Chief (Konteradmiral) of the German Imperial Navy Staff and one of the most ardent proponents for a saturated air attack on England’s capital, on a July 17th 1914 meting of the German Army High Command. The Konteradmiral’s remarks were based on his, and others high placed officers inside the armed forces, profound believe in the power of the airship.

Count Ferdinand von Zeppelin is considered by most to be the father of the dirigible. He was the first to take a powered machine to the air when Zeppelin I took off on July 2nd, 1900. Further development on lighter-than-air technology enabled the Count to built additional models, each more advance than the preceding one. Although design primarily as a commercial platform, it wasn’t long before the military began to realize the potential of the airship. In early 1909, the Army purchased two (Zeppelin I or Z.I and Z.II) units. Two additional samples were ordered in the fall. Not to be outdone, the Imperial Navy joined the fray and in 1912 ordered its first dirigible.

At the outbreak of hostilities in August 1914, the Imperial German Army possessed 10 operational airships. Nine of them Zeppelins, three of them DELAG units militarized and one Schutte-Lanz. Johann Schutte and Karl Lanz entered the airship-building industry in 1909 and began selling its platforms to the armed forces, mainly the Navy, in 1911. Four of those Zeppelins were assigned to the Western Front while three others took station on Prussia’s eastern frontier. The Navy’s sole sample, L.3, was posted on western Germany (Duren).

The Army was slow at recognizing the true power projection of the Zeppelin. In the beginning of the war, Army’s airships were use more as a low-level platform supporting the infantry crossing into Holland and Belgium. Because of its relative low operational range, British and French troops deployed in the Belgium frontier were able to shoot them down with some ease. In the first five weeks of the conflict, the German army lost 3 dirigibles. Before August ended, one more airship was lost at the Battle of Tannenberg in the eastern front. That left just 4 (3 army, 1 navy) units, including one Schutte-Lanz, available for operations.

That number (4) began to increase steadily after August ended. The Navy was the first to augment its fleet two-fold. On September 1st, the service received the first of the M-class of dirigibles, the L.4. Next January, the L.10 joined the ranks. Not to be outdone on September 3rd, the army placed an order for the newer Zeppelin P-class ship. With a hull of 531 feet, a gas capacity of 1,126,00 cubic feet and the addition of a fourth engine which gave it a top operational speed of 62 mph, the P version was the most advance airship in the world. Twenty two (22) Ps were purchased. The first to be delivered was the LZ.38, which officially became operational on April 3rd 1915. The rest of the units were incorporated to the service between May and July.

With an increase fleet housing them became a top priority. Since early 1913, the navy and army began selecting locations where to build the huge sheds needed to service the airships. Places such as Nordholz and Cuxhaven, both located in northern Germany, were the first airship bases in Europe. Each of these locations was fitted to house four dirigibles. Other bases included Tondern, Hamburg, Duren and Wittmundhaven. Later on the war Namur (Belgium) and The Hague (Holland) were incorporated. The army bases were located at Düsseldorf and Spich (Germany). After August and following the invasion of the Lower Countries, the German army erected several strategically located facilities. Belgium became the center of operations for the army’s fleet. No less than five (Maubeuge, Eterbeek, Berchem Ste. Agathe, Gontrode and Evere) bases were developed with the sole purposes of attacking Britain.

With ships and bases ready to go, the process now shifted to the strategists inside Germany. With most of the airship commanders urging their superiors to unleash their platforms and bomb England, Germany Kaiser Wilhelm and his advisors, wanting to slip the Western Allies, decided to hold-off the decision until the following summer. Unfortunately for the Kaiser, events on the ground forced his hand.

Lead by the First Lord of the Admiralty, Winston Churchill, the British struck first hitting several of the newly constructed sheds. On October 8th, the Royal Naval Air Service (RNAS) bombed the army complex at Düsseldorf destroying Z.IX. On the 21st of November, the RNAS attacked the main Zeppelin factory at Friedrichshafen causing server damage to the facility’s production line. A month later, on a clear Christmas Eve afternoon, the British attempted their most daring raid up to date. The target was the newly built Nordholz sheds. Although the attack failed to hit any structure, the German navy was very concern that if these types of attacks continued, England would eventually be able to destroy their nascent airship fleet before it could mount an offensive operation. Similar concerns were ushered by army officials. The pressure on the Kaiser was too much to bear and on January 15th 1915 he finally gave the go-ahead to bomb much of England. London would be spare for at leats s few more months as the Kaiser restricted attacks on the British capital.

Operacion Soberania

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By Raul Colon

Just days after the American and British forces broke through the German defenses at Normandy, foreshadowing the end of Nazi rule over the European Continent, much of that country’s top technical personnel began to filter out of the in hopes of escaping the ever closing circle. Most were captured by the Western Allies (United States and Great Britain); others were ‘recruited’ by the Soviet Red Army, which was rapidly pushing from the East. While another group managed to slip pass the allied hands. Most of them made their way towards South American.

The Republic of Argentina was one of the most prosperous one in Latin America. It had a big German population, a vast land rural region and Perodian government with a slight Nazi flavor. It also possessed one of the strongest militaries in the Western Hemisphere. With the arrival of several German engineers and technicians, the Argentines began formulating several advance new military projects. Chief among them were the AM-1 and PT-1 missiles. The AM-1, an air-to-air system codenamed Tabano, had the distinction of being South America’s first indigenous developed missile. As does the PT-1 air-to-ground platform.

Spearheaded by a trio of legendary German engineers, Werner von Baumbach and Ernst and Emil Henrici, Argentina began the development of its own version of the famous Henschel Hs-293, the first operational guided air-to-ground missile in the world. Designed by Baumbach and the Henrici Bothers, and built by the Specialize Weapon Section (Seccion de Armas Especiales) of the Military Construction General Direction, a subdivision of the Gaucho Army; the Argentinean version of the 293, the PT-1, was basically a complete copy of the original.

The PT-1 or Guide Missile (Projectil Teledirigido) One consisted on a 441 pound bomb warhead fitted inside a V1-type structure of 11 feet, 7 inch with a wing span of 9’10”. Total weight was 2,205 pounds. With an initial speed of 195 knots and capable of reaching speeds of 513 kts, the ‘Projectil’ had an effective 18.64 miles range. The optimum launch altitude was estimated at 22,000 feet. Operation of the system was also similar to its 293 cousin’s profile.

Operation Sovereign or Operacion Soberania, the design and development of Argentina’s first air-to-surface missile system commenced in the summer of 1952, with an specially modified Douglas C-47 Dakota. The strong built transport was fitted with a ventral boom was placed through a series of high stress, aerodynamic tests. At the same time, the newly produced PT missile was extensively examined at the Fabrica Militar de Aviones (FMA) advance wind tunnel. Also at FMA, a surplus Gloster Meteor I-087 was altered to carry a ventral pod with the tail of the missile. But the most promising launching platform was the venerable Avro Lancaster B-036 heavy bomber.

The Lancaster provided the PT with a more stable deploying system. As configured by the German engineers, the B-036 consisted of a launching rack installed below the huge bomb bay doors. On April 22nd 1953, the Lancaster replaced the Dakota as the PT’s main deploying platform. Captain Federico Muhlenber was assigned to the initial test phase. Eventually, he will be replaced later by Captain Di Pardo in that task. It was Di Pardo who will have the honor of deploying the last PT missile nearly five years later.

The 036 was assigned to the 1st Air Brigade (I Brigada Aerea). The testing phase began at earnest in October 1953. Flying out of Monzon, the home base of the VII Air Brigade, Muhlenber took the Lancaster through his phases. First it was taxing and runway operations, which ran smoothly. Then, on the 6th, the aircraft took to the air for its initial flight with the PT attached to its belly. The bomber performed flawlessly that autumn morning turning and banking without much effort.

Several more flights were made until the afternoon of the 20th when, flying above the Rio Plata, one of the left engines failed forcing the aircraft to plunge near Quilmes, a suburb of Buenos Aires. Von Baumbach, Ernst Henrici and a mechanic die in the accident. The aircraft and the missile were also lost. After the tragedy, the Argentines when back at work on another altered Lancaster, tail sign B-037. As the same time work was done on preparing the new plane, the design team slightly altered the configuration of the original Projectil.

The improve platform was called PAT-1. The only variant from the original was a larger fuel tank which gave the missile a top operational range of up to 30km. The first recorded launch of the PAT system occurred in late November 1954 at the General Soler firing range. Flying at 15,000’, the 037 entered a dive, a few seconds later Latin America’s first air-to-surface missile was released.

Work on the system continued until September 17th 1955, when the government decided to introduce it as part of their efforts to stem the tide of the rebel forces in the country’s Revolucion Libertadora. The first target of the PAT-1 was to be the Pajas Blanco Airport at Cordoba. But before the Lancaster B-037 was able to take off, an incoming rebel Lincoln aircraft bombed the Monzon base destroying the sole aircraft capable of firing the PAT platform.

By 1956 the air force had modified another Lancaster, B-043 and testing resumed at El Palomar Air Force Base at the outskirts of the River Plate. The first launch took place in the morning of October 5th. A second test was performed on the 18th. Several other deployments took place between the 19th and 21st. On the 22nd, while on taking off, the 043 suffered a small fire forcing the pilot to abort the test mission.

The end of the Revolution in 1958 also signaled the end of the PAT-1 program. With the formation of a new and democratic government under the auspices of dovish President Frondizi, many military projects were closed down, including the much promising Operacion Soberania. Now, fifty years since its maiden flight, only one sample of the first Latin America guided missile exits. Its sits at the Military School Museum in Buenos Aires.@

Lancaster B-037

Germany’s U-boats air defense systems

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Much as they did towards the end of the Great War, in the early years of World War II German’s U-Bootwaffes roamed, almost with impunity, the sea trade routes of the Western Allies, engaging and sinking their much vital shipping at an alarming rate. It wasn’t until the Allies began to implement a sophisticated system of long rage, air patrol over the Atlantic that the tide of the submarine war finally began to turn in their favor.

Because most of Germany’s U-boat force was incapable of prolonged, submerge patrol time, they became easy targets for praying allied medium and heavy bombers covering the North Atlantic.

Engaging and hitting allied patrol airplanes became the sub’s main objective from late 1943 to the end of the war in May ’45. In an attempt to achieve this task, each boat was fitted with a vast array of defensive weapon systems.

The submarine’s main anti-aircraft weapon was the 2CM Flak Gun. Two basic designs of this uninspired looking, but tremendously effective flak system were employed. The first operating 2CM was the No. 30. The thirty was a single barrel weapon with a 360 degree traverse and capable of a two degree depression and 90 degree elevation. It fired a 0.32kg shell capable of reaching distances of up to 12,350 meters. What made this weapon so effective was it impressive cycle rate of 480 rounds per minute.

The second, improved version of the 2CM was Flak 38th. Similar to the 30th, but capable of reaching a cycle rate of 960 rounds per minute, the 38th was arguably the best German, light attack weapon of World War II.

Another light weapon use by U-Boats to fend-off attackers was the 3.7CM M/42 Flak Gun. In the bottom half of the war, most German submarines were fitted with the 42nd platform. It fired a .73Kg shell up to a distance of 15,350m. Maximum firing cycle was 50 rounds per minute.

Those two weapon systems accounted for almost 85 percentage of all hit allied aircraft. Official numbers regarding hit aircrafts varies from source to source, but the most reliable figure (coming from British-generated documents released in the mid 1950s) puts the amount at 247 from the spring of 1944 to April 1945. 

Although it was not a intended as a primary anit-aircraft weapon, the vaunted 8.8CM Schiffskanone Deck Gun was also use in that role, especially towards the end. This remarkable 8.8 gun employed by the German navy was not directly related to the more famous, 8.8 Acht-Acht flack gun utilized by the army as an anti-tank weapon. The CM was purely a naval gun develop in the waning days of World War One.

The gun was mounted on a low box forward of the conning tower. It could traverse through a field of 360 degrees. Its -4 degrees depressed parameter and 30 degree elevation capacity were two of the most impressive features of this remarkable weapon. The gun fired a 13.7kg high explosive shell at a 700m/sec muzzle velocity. It had a solid impact range of up to 12,350m.

Manned by a three men crew, the CM was a powerful, horizontal weapon that when use against sea-based platforms, it caused heavy damage. As the U-Boats began to sustain alarming losses to Allies praying bombers, German crews commenced utilizing their main armament on incoming enemy aircrafts. Although their use on that type of environment wasn’t tested before the war, the gun performed well.

Data on the numbers of downed allied aircraft hit by the 8.8CM is not reliable. But unofficial accounts put the numbers in the low 50s. Much of that amount was accounted for between the autumn of 1944 and the spring of 1945.

Aside from those three defensive weapons, German submarines carried a limited amount of small caliber fire arms including 9mm and 7.62mm hand guns. Nine mili-miters machine guns and some 7.92mm rapid fire rifles. No data on hit aircraft by these weapons are available.

Of course, no weapon can be effective if the enemy isn’t spotted. For long range detection, the U-boats employed the Funkmessorungsgerat (Fu) MO-29 Radar. The MO-29 was use primarily on Type IV boats as well as some Type VIIs. The 29 was simple to utilize thanks to its twin horizontal rows of eight dipoles on the upper front part of the conning tower.

On the top row laid the transmitters and in the lower one, the receivers. An improved version of the 29 was introduced in the summer of 1942. In that version, known as No. 30, the diploes were replaced by a retractable antenna which was housed in a slot in the tower.

Although relative powerful for the times, this system barely was able to detect surface vessels because of the low position of it’s mounting in respect to the horizon.

A more complex system, FuMB1 or the ‘Metox’ was introduced in the fall of 1942. This system was utilized in conjunction with a raw, wooden cross antenna strung with copper wire know as the ‘Biscay Cross’. But as with the early Fus platforms, this unit wasn’t that reliable. In fact, a case could be mad that their use was highly detrimental to the sub’s survival thanks to the Metox’s volatile emissions which were easy detectable by Allied radars.

By November 1943, the Germans had finally develop what would become the world’s first true, all around naval radar. Born out of desperation, FuMB7 combined Metox and Naxos emissions to give U-boat commanders a first rate, long range detection system. Further enhancements were performed (the FuMB24 and 25) to the base MB7 giving it an extended operational radius. 

Aside the radar, maybe the most ingenious defensive measure used by German submarines was the Focke-Achgelis. The ‘Focke’ was basically a manned rotary glider with a triple blade rotor. It was as simple to operate as it was to assemble. Housed in a storage cylinder on the afterdeck, the Focke was quickly armed and launched. It remained connected to the U-boat by an umbilical cord. From its advantageous position high above the sub (10-12,000 feet), the pilot could spot any target approaching the boat. Unfortunately for the Focke, if the U-boat came under direct attack, there was no time to reel it in, thus the sub cut the cord and left the pilot to defend himself until all was cleared to surface back again.

 More effective than the Focke-Achgelis was the Aphrodite. It was a basic devise consisting of a large (one meter diameter) hydrogen-filled balloon from which dangled small strips of metal foil. It was attached to the sub by way of an anchor weight. Its main purpose was to confuse allied aircraft utilizing radar navigational systems.

Patriot’s Heart: The MPQ-53 Radar

Raul Colon

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No one who saw the First Gulf War in 1991 was glued to the television set looking at the majestic sight of the United States Army’s newest Theater Anti-Missile System, the now famous MIM-104 Patriot. Night after night, the vaunted weapon was launched in an attempt to intercept Iraq’s unsophisticated and terrible inaccurate Scud mid range missile. The image of America’s missile intercepting an incoming object captured the attention of almost anyone. As new and sensational as the Patriot looked in that conflict, the system was actually in its third decade of life.

Born during the height of the Cold War (1963) in an attempt by the US to overlap their complex HAWK air defense platform, the Army decided to develop the Air Defense System (AADS). More than thirty summers has passed since the first blue print for the MIM-104 was submitted for initial review. Baptized under fire in the gulf and in many other theaters, the Patriot has become America’s top defensive weapon. Multiples upgrades were performed since that summer. Changes that had improved dramatically the capability of the system.

One of the most significant modifications came in the spring of 2005 when the Patriot was fitted with the most advance targeting array in the world, the now famous MPQ-53V. The 53V is a phased array radar and associated processor that control the missile’s trajectory from its launch. The radar is a multifunctional, electronically scanned array mounted on the M-860 trailer which is towed by an M Engagement Control Center. For target identification, the 53V used the powerful Hazeltine (TPX-46-7) Target Identification Friend or Foe (IFF). A self-contain data link is use to communicate with the rest of the missile package.

The Patriot was designed to operate in all weather conditions without losing operational effectiveness. It can destroy aircraft and missiles at all altitudes. It can direct several missiles to engage multiple targets simultaneously even in the toughest electronic jamming environment. For this, the MPQ utilized a top tier lens array which operated an free optical feed. Sum and difference patterns are individually optimized with a monopulse feed optimizing its efficiency. The aperture is round and utilized around 5000 ferrite phase shifter. A four bit, flux driven, non-reciprocal ferrite phase shifter and waveguide radiators are located at both temperatures. A separate, redundant array for missile guidance and IFF is also part of the overall platform’ profile.

The most recognizable feature of radar is its face. A huge, phased array face dominates the upper part of the antenna unit. The ‘face’ performs as both, surveillance and tracking mechanism. Below the face lays an almost circular, 5000 element phase shifter which has two smaller units (each with 50 elements a piece). A row of 18 rectangular boxes divided the antenna almost in half, with access boxes. Two slight larger planar arrays are for the command-guidance and it’s receiving its links directly for the missile.

Before an engagement is achieved, the radar array has to be aligned to cover the much of expected direction of attack. During the engagement, the radio beam is steered electronically in azimuth and elevation. The system was designed in such a mater than it can prioritize a single target from several locations.

The radar utilized a Track-via-Missile (TVM) System in order to suppress its overall cost. In semi-active systems, the radar illuminates the target and a seeker in the missile’s head tracks the reflecting energy. Then the missile computes the interception pattern based on its bearing to the engaging object. The TVM allows the missile to relay the same bearing data to the engagement control station via the radar. The platform’s powerful processors comb through the information with the absolute position of the target, the missile and the profile (velocity, altitude, bearings) of the engaging object and generate tracking commands to guide the warhead to the optimums interception point. In the terminal phase, the missile’s acquisition system acquires the target and relays the data to the phase array where the final intercepting calculations are performed.

The main advantage the TVM system has over its competitors is that the powerful ground based processors are use mostly for guidance thus allowing more data interpretation time. This processing technique make it’s difficult for countermeasures to jam the Patriot’s targeting trajectory. Even when the Patriot’s targeting radar is receiving jamming strobe, its missile can still maintain missile-to-target bearing data from the TVM system. On top of this, the ground based processors have sufficient computing power to resolve troubling jamming issues such as blinking jamming, where two aircrafts in formation jam alternatively to frustrate home-on-jam modes.

Raytheon, the Patriot’s primary contractor (its have all the Defense Department contracts for the system that surpassed the $ 5 million mark) had produced a reported 128 MPQ-53V units for the US Army and an estimated 26 for Japan’s Self Defense Force (2007 totals). Price for each unit is around $ 2.5 million.

Technical Data

Weight 79,008lb
Length 56.08ft
Height 11.83ft
Width 29.42ft
Frequency 4-6 GHz
Range 68km
Detection Sector 120deg
Engagement Sector 90deg
Target Capacity 50 simulations
Missile Control Capacity 9 in final engagement

The Graceful EC-121 Early Warning Star

Raul Colon

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Embed the most advanced electronic detection systems within the slick airframe of a Lockheed Super Constellation and you will have one of the most beautiful-looking aircraft that ever graced the sky: the Lockheed EC-121 Airborne Radar System. Between the early years of the 1950s thru the mid 1960s, the 121 guarded the United States coastline against a surprise enemy air incursion. It saw extensive action in Vietnam where its advanced electronic detection systems provided US force commanders with an in-depth look at the enemy’s movements, not only in the air, but also on the ground and on the seas. The 121 program had its roots at the end of the Second World War, when US military planners were facing what they thought would be an overwhelming Soviet Air Force superiority and they would need as much warning as possible to deploy their air and naval assets. Following the normal development path, the 121 entered full production mode in the early 1950s. The Warning Star, as the EC-121 was officially known – its crew knew it as the “Wily Victor” – first entered front line service with the US Navy in October 1955.

The Warning Star was designed for long and taxing patrols, thus the aircraft retained all the comforts of the airliner on which it was based. The flight deck was roomier than previous military planes, a feature well appreciated by its crew. The pilot and copilot were seated in the front of the aircraft’s cockpit; the flight engineer was seated directly behind them. The radio operator and flight navigator were seated at the end of the cockpit structure. Two rows in the middle of the fuselage were used to house 28 electronic operators who collected and directed information received from the Star’s radar arrays. One of the main reasons Lockheed selected the Constellation airframe to incorporate the most advance airborne radar system designed, was the need to locate the radome on the underside of the airframe. The Constellation had the required ground clearance because of its long undercarriage. The rear part of the aircraft was used to provide the crew with a comfort station. Four bunks and a primitive toilet were placed in the tail end of the 121. A small kitchenette was also installed there. Propelling the aircraft were four 2535-Kw Wright R3350-34 radial piston engines capable of generating 3,400 hp. The 121 could stay airborne for up to thirty five hours without refueling.

Four squadrons of the Warning Star were formed in the mid 1950s. Operating from bases in Scotland and Iceland, Warning Stars performed around-the-clock air patrols over the North Atlantic. They also operated from US Navy bases in Puerto Rico and Cuba. They saw combat action in the sky over Vietnam, offering assistance and relaying electronic information to US aircraft operating in the area. Only one EC-121 was lost during a combat operation. One 121 was shot down near North Korean territorial waters in 1969. The aircraft was lost along with its complementary crew. In the early 1970s, the US Air Force and Navy replaced its respective fleets of EC-121 Warning Stars with the first truly AWACS system platform: Boeing’s E-3. Today we can still see some Warning Stars gracing the skies above the US. All remaining 121s are privately owned and are flown at air shows all across America.

– Raul Colon

More information:
wikipedia: EC-121 Warning Star

Latest Russian Air Force Bomber
Developments

Raul Colon

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The end of the Cold War and the new financial realities within the Russian Federation in the early 1990s, accelerated the decommissioning, and eventual termination of large portions of the former Soviet Union’s Strategic Bomber Force on-going development programs. In addition to these cutbacks, new aircraft development programs have been dramatically cutback and the aircraft industry itself no longer reflects the one that dominated Soviet society from the late 1940s onward. Nevertheless, studies into future bomber developments have continued, although relatively little information has so far, been made available to the general public regarding Russia’s newest bomber designs. The following is a partial view of some of the work that the Soviet Union undertook since the early 1980s. But, as with all related aircraft design information, it’s difficult to verify if any of these programs are still active today. In the early 1990s, the Mikoyan Bureau commenced a research study into a hypersonic, high-altitude reconnaissance aircraft, which may also have being given the designation of bomber. The Mikoyan 301, as the type was designated, could had flown at speeds of over Mach 3.5 utilizing special hybrid power plant that would operate in flight as a ram jet engine. To cope with the built up of heat friction, the 301 was designed to be built completely out of an new stainless steel alloy. The aircraft’s concept design was able to take-off with a maximum weight of 176,367lb. A variable geometry wing was to be employed in the design. By the end of the 1990s and the beginning of a new century, work on this spectacular design probably would had been shelved or at best, moving on a much slower pace than original conceived by Soviet, and then Russian authorities.

The next generation Russian bomber could very well have been the incredible Sukhoi T-60S. Few, if any, detail have surfaced of this design. What it is known is that the T-60S was conceived as a supersonic, stealth heavy bomber. Re-heat wouldn’t have been fitted to the aircraft, as the plane was supposedly able to supersonically cruise at high altitude on dry power, and its weapon system platform would have included cruise missiles, second generation precision guided conventional munitions and free-fall nuclear weapons. Some have speculated that this aircraft in fact entered full scale development in early 1990, but the subsequence collapse of the Soviet Union at the end of 1991, prevented any additional work on the project. In the summer of 1998 it was widely reported that the project was still ongoing as a possible replacement for the Tu-16 and Tu-22M bombers.

From the early 1980s onward, the Tupolev Design Bureau began to look for a potential successor to its successful Tu-160 bomber platform. The end result of these studies produced a pair of hypersonic aircraft projects. The first, designated Aircraft 260, was, from 1983 forward, intended to fly at Mach 4 at an operational ceiling of 83,000 ft and was to have an un-refuelled range of 6,215 miles. This aircraft was proposed to be powered by four Soloviev D80 jet engines mounted in a side-by-side configuration beneath a double delta wing configuration. The aircraft would have had a relatively flat main fuselage. There was to be no tail-plane on this new bomber, just a single tall fin. Its fully-loaded take off weight was around 396,825lb. A preliminary design project was completed by the fall of 1985. The next hypersonic plane design to surface in relation with Tupolev’s future design program was Aircraft 360. It had a similar layout to the 260 project, but was bigger and supposedly capable of speeds in excess of Mach 6 with an un-refuelled range of 9,323 miles. It could carry a massive bomb load of 22,046lb. Aerodynamics studies suggested that with a constant cruise speed of Mach 6, the aircraft would lose about three thousand miles in operational range. To obtain this incredible speed, the installed engines would need to utilize cryogenic fuel cells and, as a result, six hydrogen-powered units were intended to be fitted; all of them “variable cycle” types that could operated in both a turbojet and ramjet environment. There were to be two crewmen and the aircraft bomb load was to be carried in two wing root bomb bays. The design development program also envisioned the flight testing of a scale model plane weighting around 176,367lb, but the project was terminated in the fall of 1992 after some fuselage and fuel system parts had already been manufactured. Again, the program termination was in great part due to the strained financial situation in Russia

It’s also believed that Tupolev’s designers began work on a subsonic flying wing bomber concept as early as the mid 1980s, designated Aircraft 202, and with research still ongoing during the late 1990s, it was hoped by the design team that a version of this aircraft might actually reach hardware development status in the early 2000s. The aircraft was given a temporary designation of B-90, which stood for Bomber of the 1990s and the project was visualized as an intercontinental strike heavy bomber aircraft replacement for the aging Tu-95M Bear bomber fleet. But as with many of these exceptional designs, financing was a major problem and the project was cancelled in the early 2000s.

– Raul Colon

References:

1. Aircraft of OKB Tupolev, Vladimir Rigmant, Moscow Russavia 2001
2. Soviet X-Planes, Yefim Gordon & Bill Gunston, Midland Publishing 2000
3. Russian Aviation and Air Power in the Twentieth Century, Edit Robin Higman, John T. Greenwood & Von Hardesty, Frank Cass 1998