Z-Car


General Dynamics F-111 Aardvark

The F-111 Aardvark is a all weather fighter-bomber with a variable geometry wing developed by the United States in the 1960s . The development of this aircraft was difficult, but once all the problems were solved, the F-111 proved to be a formidable weapon system, and very reliable. Over 554 F-111’s were produced over twenty years.  In December 2010, it was retired from service with the Australian Army, the last to possess in service.


As early as 1968 , the F-111A was sent to fight in Vietnam. Following the loss of several aircraft, all F-111 were banned from flying in December 1969 to July 1970. Three problems were discovered and fixed: the first in the motion control of the rudders, and the other two are the weaknesses of the structure at the wings. The war missions revealed various other malfunctions in the electronic systems, and in case of heavy rain, problems with the engines. Despite this, the F-111 proves capable of performing missions a variety of missions, and took over many bombing missions from the lesser capable F-4 Phantom.

All models of the F-111 (except the Australian F-111C) were equipped to carry the nuclear weapons . Tactical versions typically can carry the B43 , B57 or B61 , while the FB-111A can also carry the B77 and B83.


The Rolls-Royce Merlin – Could it be the best piston engine ever?

The RAF fighters which resisted the German invasion in 1940 during the Battle of Britain, were all equipped with the same engine, the Rolls-Royce Merlin.  This same engine also powered the majority of the bombers of RAF Bomber Command, and some of the best fighters of the 8th USAAF.   Named after a bird of prey, like all piston engines that Rolls-Royce produced, the Merlin is a unique engine for several reasons.

  • Unlike other engines, which changed relatively little during the war, between 1939 and 1945, no fewer than 52 different versions of the Merlin were produced
  • Powered a wide variety of aircraft, including both fighters and bombers.  These included the Spitfire, Hurricane, Boulton Paul Defiant, Avro Lancaster, De Havilland Mosquito, Handley Page Halifax, Armstrong-Whitworth Whitley, and the P-51 Mustang.  The Merlin even replaced the Hercules II version of the Bristol Beaufighter and the Pegasus in version II of Wellington.
  • The Merlin transforms two of the most important aircraft of World War II.  From the poor performing Manchester was born the transformed Merlin powered Lancaster, the legendary aircraft of Bomber Command.  The P-51 Mustang became one of the best fighters in WWII once the under-powered Allison’s were replaced with the Merlin.  With the new found extended range, it became the only fighter to effectively protect the 8th USAF B-17 deep into enemy territory.
  • Finally, it is the only engine to be built in large numbers simultaneously on both sides of the Atlantic during WWII.

The Birth of the Merlin

The Merlin is a conventional engine, derived from relatively older power trains, as engineers and technicians at Rolls-Royce simply evolved the Merlin from existing proven designs. The Merlin was born into a family of  V12 engines whose origin dates back at Rolls-Royce to the First World War.  As mentioned, they all  bear the names of birds of prey, when studying reciprocating engines from Rolls Royce, you also get a lesson in  ornithology.   Rolls entry into aeronautical engines begins with the Eagle in 1915.  The V-12 Eagle propels the Short Bomber (1916), the Vickers Vimy (1917), the Handley Page O/100 (1916), the Handley Page V/1500 (1918), and fighters like the AIRCO DH.4 (1917).  The Eagle is also mounted in the U.S. aircraft (Fairey F.17).  The Eagle was rated between  250 and 375 hp in its various versions, which for the time was a considerable amount of power, and advantage that the water-cooled engines had over the air-cooled engines of the day.   During this time period the Americans, British and French prefer the V-12 engines from  Rolls Royce, Hispano-Suiza, Renault, and Liberty.  The Germans and Italians are loyal to the 6-cylinder Mercedes, Fiat and Isotta-Fraschini.

After the war, Rolls-Royce began, like all its competitors, the race for power, while remaining faithful to the formula of V-12 liquid cooling.  Advances in design, metallurgy, and fuel allow for an increase in the speed (RPM) and compression ratio of the engine.  In 10 years, the compression ratio increases by 50% (it goes from 4: 1-6: 1) and the rotational speed from approximately 1800 to 2400 rpm. In 1927, the Kestrel 21.25 liter engine is released, which soon powers the Hawker biplanes (Audax, Fury, Hart) in the early 1930s.  The Kestrel develops 745 hp, double the power of the engines produced at the end of WWI.  In order to compensate for lower density air at higher altitudes, the Kestrel gets a mechanical compressor, the super-charger, the first turbocharged engine Rolls-Royce produces.  With the gasoline at that time rated at 87 octane, it allowed for a boost pressure of 5.6PSI.

The Kestrel turns out to be a great engine, with innovations such as the use of ethylene glycol for cooling which reduces the size of the radiators.  Interestingly, Messerschmidt, which still awaits the Daimler-Benz V12 engine, will acquire a Kestrel to test the first version of the BF 109 in 1935.  However, the displacement of the Kestrel is a bit inadequate for the next generation of fighters will require, such as Britain’s future Spitfire.

The Kestrel was followed in 1929 by the Buzzard (36.7 liters), which was named Type R in its competition form. It is with the 2300 hp R-type aircraft that race Supermarine S6 allows England to win for the third consecutive time in the 1931 Schneider Cup and beat the world speed record at 407MPH.  However, the Type R is a racing engine, whose performance can only be sustained for a short period of time.

To fill the existing hole in the range between Kestrel and Buzzard, Rolls began to privately develop a new V12 called the PV 12 (Private Venture 12).  In October 1934, the Air Ministry officially orders the PV12 into production and it is given the name Merlin.  For the next 10 years, Rolls-Royce will continue to develop the Merlin, to make it ever more powerful and versatile.

The Merlin I and II : In July 1934, Rolls releases the first pre-production Merlin A, which like many motors, has a bore (137 mm) which is slightly less compared to the stroke (152 mm), a feature that promotes low-end torque. The Merlin is estimated at 790 hp at 2500 rpm at an altitude of 12,000 feet, already outstanding performance for a block that weighs less than 1322 pounds dry (no oil or coolant).  At the same time (Feb 1935), another version (Merlin B) is produced with a redesigned combustion chamber and 4 valves per cylinder, it reached 960 hp at 11,000 feet. The changes follow through F, to be released in small numbers with the name of Merlin I. The Merlin G (called Merlin II production) is the first type for mass production, it reached 1030 hp at 3000 rpm and 16,250 feet. Compared to the type A, the Merlin type G has gained 30% in power, while the weight has increased by 220 pounds. The Merlin II has a single-speed super-charger, and with 87-octane fuel limit has a boost pressure up to 5.6PSI, and in 1939 with the introduction of 100 octane fuel, this was increased to 11.2PSI, improving power at high-altitude.

The X Merlin : The Merlin X represented a milestone in the evolution of Merlin with the introduction of a two-speed compressor.  Driven by the engine, the supercharger requires power to compress the incoming air.  Therefore, it is important that the power required to compress the air does not exceed the power gained.  The two-speed compressor would allow a lower pressure when the engine was at low to medium altitude, and only use maximum pressure at high altitude.  With the adoption of this compressor Rolls-Royce significantly improves the performance of the Merlin.

Series 60 and Beyond : For the 60 series, the Merlin receives a two-stage compressor. Rather than resorting to turbocharging, which Rolls Royce has no experience, and requires special alloys, Sir Stanley Hooker (Merlin Head Engineer) prefers to mount a two-stage compressor.  This again allows efficient low altitude performance, while increasing high altitude performance.  The ultimate development of this technology will lead to the series 100, which develops over 2000 hp at sea level, and retains a power of 1000 hp at 12,000 ft, with a boost pressure of  2.8PSI.  With the two-stage compressor, Rolls-Royce has the Merlin which is the envy of American turbocharged engines.

The Merlin in Action

Almost all British aircraft, fighters or bombers, were, during the war, equipped with the Merlin. With its V configuration, Merlin offered a reduced frontal area, which was perfect for swift fighters.  Two of these mythical Battle of Britain fighters were the Spitfire and Hurricane. The first Spitfire and Hurricane used the Merlin II. Although designed for fighters, the Merlin also powers almost all British bombers, first the twin-engine bombers (Stirling, Whitley, Mosquito) and then the four-engined Lancaster and Halifax.  The Merlin power plant is also installed in two American fighters, the Curtis P-40 in limited numbers, and the P-51 Mustang almost excusively.


B-17 E-Z Goin’ and the Sonderkommando Elbe – Buchen Raid

Laurence J. Lazzari Crew
Kneeling L to R: Sgt. Laurence W. Donnelly (BTG), T/Sgt. Robert J. Steele (ROG), 2nd Lt. Charles W. Staiger (NAV)Sgt. Joseph G. Allen.  Standing L to R: Sgt. Richard H. Heritage (NG/TOG), T/Sgt. Charles A. Weiss (TTE), 2nd Lt. Laurence J. Lazzari (P),
2nd Lt. Guiher G. Greenwood (CP), 2nd Lt. Daniel J. O’Connell, Jr. (TG).
100th BG Photo Archives

This website recently received a comment from USAF Colonel Guiher G. Greenwood (retired) who served with the 351st Bomb Squadron, 100th Bomb Group, regarding a picture posted in our gallery. He identified the plane pictured as that of the B-17 E-Z Goin’ piloted by Joe Martin with co-pilot Henry Cervante on the Buchen raid of April 7, 1945. Interestingly, Col Greenwood and Joe Martin lived through one of the more infamous “suicide” attacks by the Germans in their last desperate days of the war.

The Sonderkommando Elbe was a special squadron of the German Luftwaffe, a Luftwaffe task force assigned to bring down Allied bombers by ramming German aircraft into the Allied bombers. Sonderkommando means special command, and Elbe is a river that runs through Germany to the North Sea. The Sonderkommando Elbe was formed at Reichmarschall Hermann Goering’s insistence that the Reich’s defense units should start ramming bombers as a last resort. This group of fighters was not solely tasked with ramming bombers, but that was their last ditch option. In theory this was not a suicide mission, they were only supposed to ram an Allied bomber if there was a chance to bail out alive. Unlike the Japanese kamikaze pilots, the inexperienced German pilots brought a parachute with them while flying their striped-down Messerschmitt Bf 109’s, if the pilot survived the collision, he could use the parachute.

The only documented mission, often called Rammkommando Elbe (ramming) or Werewolf, was on April 7, 1945 when a total of 120 pilots took off in their fighters and attacked several formations of U.S. bombers heading towards the Germany heartland. These young German pilots were motivated to destroy Allied bombers by any means necessary, they had seen their country decimated by the relentless Allied bombing campaign. Although the Luftwaffe had an amply supply of airplanes, even in April 1945, they lacked trained pilots and aviation fuel. Many of the Sonderkommando pilots had only 50 hours of training, and their lack of experience was as likely to get them killed as the P-51 Mustangs that protected the Bomber Armada.

This last ditch effort of the mighty Luftwaffe resulted in only 15 Allied bombers attacked with eight successfully destroyed. Several planes barely limped back to base, these included the E-Z Goin’ flown by Joe Martin’s crew. Their left stabilizer was ripped off, and the rudder substantially damaged. In addition to having little control of the plane, they also lost engine #1. Somehow the crew was able to return to England, and landed successfully.

 


 


Lockheed Martin RQ-170 Sentinel – Beast of Kandahar

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The US Air Force today confirmed that it is using a drone named the RQ-170 Sentinel, in Afghanistan. The stealthy unmanned aircraft system is developed by the Lockheed Martin’s Skunk Works division, the same company that developed the F-117 Stealth Fighter. However, the RQ-170 looks like a scaled down version of the B-2 Spirit Stealth Bomber. The USAF confirms that the RQ-170 Sentinel is in development, and is expected “to provide reconnaissance and surveillance support to forward-deployed combat forces”, according to a statement released on 4 December.

This announcement comes after a series of images of a jet-powered, stealthy aircraft have appeared on the internet last April, including a clear shot of the aircraft that circulated widely in early December. Besides describing the RQ-170 as stealthy, the USAF released no further technical information about its new UAV, or any photos. This plane has also been rumored to be called the “Beast of Kandahar”. The main purpose of the drone has been reported to be providing aerial and strategic information to the ground forces battling in Afghanistan. “RQ” represents that the aircraft is unmanned and unarmed, which is different from other drones named with “MQ” which are loaded with laser guided weapons.

The aviation authorities coined the name of the aircraft as “Beast of Kandahar” after its 2007 pictures were released which showed the aircraft in action in Afghanistan. The pictures gave the description of an aircraft that resembles a drone that has the ability to cheat radar and has the shape which resembles that of a stealth aircraft. Several aviation journals have made speculations about this mysterious aircraft and have published its pictures. The presence of “Beast of Kandahar” in the region has questioned why the U.S. is using such technology in a warzone where there are no radar systems available to militants. This has pointed towards the possible us of the drone over Iran and Pakistan. According to reports, the U.S. air force has targeted many terrorists in Pakistan with the help of Predators and Reaper drones.
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