Z-Car

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.


Lockheed Martin F-16 Fighting Falcon

The U.S. Air Force officially named the F-16 “Fighting Falcon” on July 21st, 1980, during a ceremony at Hill AFB in Utah.

The F-16 Fighting Falcon is a compact, multi-role fighter aircraft. In the air combat role, the F-16’s maneuverability and combat radius exceed that of all potential enemy fighter aircraft. It can locate targets in all weather conditions and detect low flying aircraft in radar ground clutter. In the air-to-surface role, the F-16 can fly over 500 miles, deliver its weapons accurately, defend itself, and return to base. An all-weather capability allows it to accurately deliver ordnance during bad weather or at night. With a full load of internal fuel the F-16 can withstand up to 9G’s, it’s likely the pilot will fail before the airframe does.. The bubble cockpit canopy gives the pilot unobstructed vision forward and upward and much improved vision over the side and rear.

The F-16 first flew in December 1976. The first operational F-16A was delivered to the 388th TFW at Hill AFB, Utah in January 1979. The two-seat version, the F-16B, has two cockpits each about the same size as the single ‘A’ version cockpit. To make room for the second cockpit the forward fuselage fuel tank and avionics growth space is reduced.

The Falcon was one of the first to use the now standard fly-by-wire control system whereby no direct mechanical link is provided, instead the pilot’s controls communicate with the F-16 ‘s electronics which in turn move the aircraft’s flying surfaces. This system requires a side-mounted control stick instead of the conventional between the knees joystick that came as standard with combat planes since the beginning, needed for better control during the high-G maneuvers the plane can fly.

To simplify and cut the cost of development and production of the Falcon, some existing and proven systems from other USAF aircraft were adapted for it’s use. Parts used in the earlier F15 Eagle and the old swing wing F111 fighter bomber found a home in the aircraft. Unusually the F16 Falcon has a single engine instead of two. While cutting the cost of the aircraft and also maintenance time it does always increase the chance of a ‘dead stick landing’, however the F16 has proven reliable in the field.

The Lockheed Martin F-16 Fighting Falcon, the first of the US Air Force multi-role fighter aircraft, is the world’s most prolific fighter with more than 2,000 in service with the USAF and 2,000 operational with 23 other countries.

Lockheed Martin F-16 Fighting Falcon

 

 

 

 

 

 

 

 

 

 

 

 

 

Specifications
Primary Function Multi-role fighter
Builder Lockheed Martin Corp.
Power Plant F-16C/D:
one Pratt and Whitney F100-PW-200/220/229 or
one General Electric F110-GE-100/129
Thrust F-16C/D, 27,000 pounds(12,150 kilograms)
Length 49 feet, 5 inches (14.8 meters)
Height 16 feet (4.8 meters)
Wingspan 32 feet, 8 inches (9.8 meters)
Speed 1,500 mph (Mach 2 at altitude)
Ceiling Above 50,000 feet (15 kilometers)
Maximum Takeoff Weight 37,500 pounds (16,875 kilograms)
Combat Radius [F-16C]

740 nm (1,370 km) with 2 2,000-lb bombs + 2 AIM-9 + 1,040 US gal external tanks
340 nm (630 km) with 4 2,000-lb bombs + 2 AIM-9 + 340 US gal external tanks
200 nm (370 km) + 2 hr 10 min patrol with 2 AIM-7 + 2 AIM-9 + 1,040 US gal external tanks

Range Over 2,100 nm (2,425 mi; 3,900 km)
Armament One M-61A1 20mm multibarrel cannon with 500 rounds; external stations can carry up to six air-to-air missiles, conventional air-to-air and air-to-surface munitions and electronic countermeasure pods.


Lockheed Martin F-22 Raptor

The F-22A Raptor is a next-generation fighter/attack aircraft that features the latest stealth technology to reduce detection by radar. Using more advanced engines and avionics than the current F-15 Eagle, the F-22A is intended to maintain U.S. Air Force capabilities against more sophisticated enemy aircraft and air defenses in the 21st century.


The Raptor combines stealth, maneuverability and the ability to fly long distances at supersonic speeds — or “super cruise” — in performance of air superiority and air-to-ground missions. Furthermore, it requires less maintenance than older fighters. These capabilities represent an exponential leap in war fighting capabilities.

In 1981 the U.S. Air Force needed a new air superiority fighter that would take advantage of new technologies in fighter design including composite materials, lightweight alloys, advanced flight control systems, higher power propulsion systems and stealth technology. Lockheed Martin’s F-22 won the design competition in April 1991, and the rollout ceremony for the first F-22 Raptor occurred in April 1997.

The Raptor successfully completed its initial operational and test evaluation in 2004, and the program received approval for full rate production. In December 2005 operational aircraft were designated F-22As.

Production of the F-22A is a partnership between Lockheed Martin, Boeing and Pratt & Whitney. Boeing builds the Raptor’s wings and aft-fuselage; the engines come from Pratt & Whitney, and Lockheed Martin builds the forward fuselage and assembles the subsections in Marietta, Ga.

On May 12, 2005, the Raptor program achieved a historic milestone with the delivery of the first combat-capable Raptor to the 27th Fighter Squadron, 1st Fighter Wing, at Langley Air Force Base, Va. In January 2006 the 27th Fighter Squadron flew the first operational mission with the F-22 in support of Operation Noble Eagle (the official name given to the defense of U.S. borders).

A combination of sensor capability, integrated avionics, situational awareness, and weapons provides first-kill opportunity against threats. The F-22A possesses a sophisticated sensor suite allowing the pilot to track, identify, shoot and kill air-to-air threats before being detected. Significant advances in cockpit design and sensor fusion improve the pilot’s situational awareness. In the air-to-air configuration the Raptor carries six AIM-120 AMRAAMs and two AIM-9 Sidewinders.

The F-22A has a significant capability to attack surface targets. In the air-to-ground configuration the aircraft can carry two 1,000-pound GBU-32 Joint Direct Attack Munitions internally and will use on-board avionics for navigation and weapons delivery support. In the future air-to-ground capability will be enhanced with the addition of an upgraded radar and up to eight small diameter bombs. The Raptor will also carry two AIM-120s and two AIM-9s in the air-to-ground configuration.

Advances in low-observable technologies provide significantly improved survivability and lethality against air-to-air and surface-to-air threats. The F-22A brings stealth into the day, enabling it not only to protect itself but other assets.

The F-22A engines produce more thrust than any current fighter engine. The combination of sleek aerodynamic design and increased thrust allows the F-22A to cruise at supersonic airspeeds (greater than 1.5 Mach) without using afterburner — a characteristic known as super cruise. Super cruise greatly expands the F-22A ‘s operating envelope in both speed and range over current fighters, which must use fuel-consuming afterburner to operate at supersonic speeds.

The sophisticated F-22A aero design, advanced flight controls, thrust vectoring, and high thrust-to-weight ratio provide the capability to outmaneuver all current and projected aircraft. The F-22A design has been extensively tested and refined aerodynamically during the development process.

From the very beginning, the F-22A exceeded the USAF’s expectations, and during exercises and deployments, it proved to be more than a match for any fighter opposing it.

During the highly realistic Exercise Northern Edge 2006, the F-22 proved itself against as many as 40 “enemy aircraft” during simulated battles. The Raptor pilots achieved a 108-to-zero “kill” ratio against the best F-15, F-16 and F-18 “adversaries.” The stealthy F-22A also proved that it could avoid and destroy enemy surface to air missiles, and recorded an impressive 97 percent mission capability rate.

Specifically noting the Raptor’s performance at Northern Edge, the National Aeronautic Association (NAA) awarded its 2006 Robert J. Collier Trophy, considered America’s most prestigious award for aeronautical and space development, to the Lockheed Martin Corp.-led F-22 Raptor aircraft team “for designing, testing and operating” the Raptor. Team members included Lockheed Martin, Boeing, Pratt & Whitney, Northrop Grumman, Raytheon and BAE Systems. This amazing aircraft was described as “the most efficient and effective fighter in history, through exceptional performance and outstanding safety features.”

The F-22A will have better reliability and maintainability than any fighter aircraft in history. Increased F-22A reliability and maintainability pays off in less manpower required to fix the aircraft and the ability to operate more efficiently.

Specifications
Primary Function: Air dominance, multi-role fighter
Contractor: Lockheed-Martin, Boeing
Power Plant: Two Pratt & Whitney F119-PW-100 turbofan engines with afterburners and two-dimensional thrust vectoring nozzles.
Thrust: 35,000-pound class (each engine)
Wingspan: 44 feet, 6 inches (13.6 meters)
Length: 62 feet, 1 inch (18.9 meters)
Height: 16 feet, 8 inches (5.1 meters)
Weight: 43,340 pounds (19,700 kilograms)
Maximum Takeoff Weight: 83,500 pounds (38,000 kilograms)
Fuel Capacity: Internal: 18,000 pounds (8,200 kilograms); with 2 external wing fuel tanks: 26,000 pounds (11,900 kilograms)
Payload: Same as armament air-to-air or air-to-ground load outs; with or without 2 external wing fuel tanks.
Speed: Mach 2 class with super cruise capability
Range: More than 1,850 miles ferry range with 2 external wing fuel tanks (1,600 nautical miles)
Ceiling: Above 50,000 feet (15 kilometers)
Armament: One M61A2 20-millimeter cannon with 480 rounds, internal side weapon bays carriage of two AIM-9 infrared (heat seeking) air-to-air missiles and internal main weapon bays carriage of six AIM-120 radar-guided air-to-air missiles (air-to-air load out) or two 1,000-pound GBU-32 JDAMs and two AIM-120 radar-guided air-to-air missiles (air-to-ground load out)
Crew: One
Unit Cost: $142 million
Initial operating capability: December 2005
Inventory: Total force, 91


McDonnell Douglas F-15 Eagle

The F-15 Eagle is probably the most recognizable military jet fighter in the skies today having held the distinction of the premier jet fighter over the past 30 years. The F-15 is the only operational jet fighter to have never been shot down in combat. Along with the US, the air forces of Israel, Saudi Arabi, and Japan have all flown the F-15.

The F-15 was designed to remain highly maneuverable in all weather conditions and to carry a variety of weapons. The F-15’s superior maneuverability and acceleration are achieved through high engine thrust-to-weight ratio and low wing loading. Low wing-loading is a vital factor in maneuverability and, combined with the high thrust-to-weight ratio, enables the aircraft to turn tightly without losing airspeed.

The pilot’s head-up display projects on the windscreen all essential flight information gathered by the integrated avionics system. This display, visible in any light condition, provides information necessary to track and destroy an enemy aircraft without having to look down at cockpit instruments.

The first F-15A flight was made in July 1972, and the first flight of the two-seat F-15B trainer was made in July 1973. The first Eagle F-15B was delivered in November 1974, and in January 1976, the first Eagle destined for a combat squadron was delivered.

The single-seat F-15C and two-seat F-15D models entered the Air Force inventory beginning in 1979.

The F-15E Strike Eagle is a two-seat, dual-role, totally integrated fighter for all-weather, air-to-air and deep interdiction missions, 237 were built between 1985-2001. The rear cockpit is upgraded to include four multi-purpose CRT displays for aircraft systems and weapons management. The digital, triple-redundant Lear Siegler flight control system permits coupled automatic terrain following, enhanced by a ring-laser gyro inertial navigation system.

McDonnell Douglas F-15 Eagle

Specifications
Speed: 1,875 mph
Range: 2,400 miles
Height: 18 feet 8 inches
Length: 63 feet 9 inches
Wingspan: 42 feet, 10 inches
Weight: 68,000 pounds


Lotus Evora – Cool Name, Cool Car

2010_lotus_evora_400

Lotus officially announced the new Evora, previously known by the code name Eagle. This is the first all new Lotus since the Elise made its debut in 1995. Currently, this is the world’s only 2+2 mid-engine sports car. Although, Lotus is careful to warn that the back seats are only suitable for children or those with very small legs.

This Lotus still retains its sporting heritage, however much attention has been made to make it a more practical and comfortable car. Those familiar with the Elise/Exige are familiar with the contortions required to enter and exit the vehicle. The new Evora has wider and taller door openings, and the sills are narrower, making it easier to slide over.

Similar to other Lotus, it is mid-engine, and lightweight, although at 2976 pounds, it tips the scales at almost 1000 pounds more than the svelte Elise/Exige. To help propel that increased weight, a Toyota 3.5-liter V-6 is stuffed behind the passenger cabin. This engine churns out 276 horsepower and 252-lb-ft of torque. That is enough to push the car from 0-60MPH in five seconds with a top speed of around 160MPH.

While clearly not as sporting as the Elise/Exige, which are essentially street-legal race cars, the Evora will help lure those who are used to comfortable sports cars such as the Porsche Cayman. The classy styling, lower price (~60K), and exclusivity may help steer younger would-be Porsche customer into a Lotus.


Where I have been – cars that I have owned over the years

lotus in a field

These are some of the cars I have owned in the past, starting with the first car I ever owned.

1976 Datsun 710
1970 Datsun 240Z
1987 Toyota MR2
1988 Toyota Celica All-Trac
1972 Datsun 240Z
1991 Eagle Talon
1992 Mazda Miata
1991 Toyota MR2 Turbo
1994 Mazda RX-7
1968 Datsun Roadster
1970 Datsun 240Z
1976 Datsun 260Z
1998 BMW M3
1997 Mazda Miata
1993 Mazda RX-7 CYM
2003 Mazda Miata
1987 Toyota SDK8
2005 Lotus Elise
2006 Infiniti G35x
1997 Ford F150
2011 Infiniti M37x
1994 Mazda Miata

I have also owned a couple Tundra’s, T100, and Troopers mixed in there as well.  What was my favorite car?  I love my current Lotus Elise, however my 1993 RX-7 CYM was probably my all time favorite.  The Talon was most reliable, it went over 150K miles, very few of them were what you would call “easy” miles.  My 2006 Infiniti cleared 170K miles before finally giving up one of its cylinders.