War Emergency Power: Unleashing Tactical Dominance in Critical Combat Scenarios

By Fouad Sabry

What is War Emergency Power

The term "war emergency power" (WEP) refers to a throttle setting that was initially implemented on some military aircraft engines used by the United States during World War II. It was designed to be utilized in emergency situations, and it was capable of producing more than one hundred percent of the engine's standard rated power for a short period of time, often around five minutes. Although they may not have been known as WEP at the time, similar systems that were deployed by non-US forces are now frequently referred to as WEP as well. For example, the German Luftwaffe's Notleistung and the Soviet VVS' forsazh systems are examples of such systems.

How you will benefit

(I) Insights, and validations about the following topics:

Chapter 1: War emergency power

Chapter 2: Allison V-1710

Chapter 3: Turbofan

Chapter 4: Turbojet

Chapter 5: BMW 801

Chapter 6: Afterburner

Chapter 7: General Electric F110

Chapter 8: General Electric F101

Chapter 9: Pratt & Whitney R-2800 Double Wasp

Chapter 10: Rolls-Royce Dart

(II) Answering the public top questions about war emergency power.

Who this book is for

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of War Emergency Power.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: Jun 24, 2024

Book preview

Chapter 1: War emergency power

War emergency power, sometimes known as WEP, is a throttle setting that was available on certain military aircraft engines used by the United States during World War II. It was designed to be utilized in emergency situations, and it was capable of producing more than one hundred percent of the engine's standard rated power for a short period of time, often around five minutes. Although they may not have been known as WEP at the time, similar systems that were employed by non-US forces are now frequently referred to as WEP as well. Examples of such systems include the Notleistung system used by the German Luftwaffe and the forsazh system used by the Soviet VVS.

There would be a mechanical stop that would limit the maximum typical power, such as a wire that would be placed over the slot of the throttle lever. However, if the push was more powerful, the wire would break, which would allow for additional power. The P-51H Mustang was rated at 1,380 horsepower (1,030 kW) while it was in normal duty; however, the WEP was capable of delivering up to 2,218 horsepower (1,654 kW). This improved the Merlin III engine rating to 1,310 horsepower (980 kW), which is a gain of more than 250 horsepower (190 kW). The pilots were required to keep a journal of their usage of the emergency boost, and they were cautioned against using it for more than five minutes in a row.

The methanol-water injection system that was installed in the German MW 50 required additional plumbing in addition to a storage tank, which resulted in an increase in the total weight of the aircraft. The Focke-Wulf Ta 152H high-altitude fighter, which was one of the few German aircraft that could be equipped with both Notleistung systems, was able to achieve a velocity of around 470 miles per hour (756 kilometers per hour) when both systems were utilized together for the first time. It is said that Kurt Tank once performed this, used both boost systems simultaneously, in order to escape a flight of P-51D Mustangs in April of 1945. He was flying a Junkers Jumo 213E-powered Ta 152H prototype that was fitted with both MW 50 and GM-1.

The WEP function that was discovered in the MiG-21bis fighter jet was almost certainly the most impressive one. It was a stopgap measure to counter the more advanced and powerful American F-16 and F/A-18 fighters until the next-generation MiG-29 could be placed into service. This late variation of the basic Soviet light fighter plane was constructed as a stopgap measure.

An enhanced version of the Tumansky R-25 engine was installed in the MiG-21bis, which retained the standard 9,400 / 14,600 lbf (42 / 65 kN) normal and afterburner power settings of earlier R-13 powerplants, On the other hand, with an emergency thrust boost from an overspeed to 106% and an increase in afterburner fuel from a second afterburner fuel pump, the vehicle was able to.

During times of war, the utilization of this boost capability resulted in a maximum thrust of 21,900 Lbf (97.4 kN) for a period of two minutes.

The MiG-21bis was able to achieve a climb rate of 50,000 feet per minute (254 meters per second) with a thrust-to-weight ratio that was slightly better than 1:1, competing with the capability of the F-16 in a dogfight.

Due to the fact that every second of WEP thrust was comparable to many minutes of running without it, the use of WEP thrust was restricted to a maximum of one minute during air combat training with the MiG-21bis. This was done in order to decrease the impact on the engine on the 800 hours of time that passed between overhauls. The R-25 produced a blowtorch exhaust that was 16 feet (5 meters) long when WEP was selected. The name diamond regime was given to the emergency power setting because of the six or seven brightly lighting rhomboid shock diamonds that were visible inside the flames.

It is possible for the engines of the F-15 fighter jet to fire at a temperature that is 22 degrees higher and approximately 2 percent more revolutions per minute thanks to the Vmax switch. It is secured with a safety wire. The pilot would receive a tiny bit extra thrust if they pulled the Vmax switch when they were engaged in combat at the time. On the other hand, the engines would then require maintenance and a complete overhaul.

Additionally, WEP features are utilized by several contemporary military surface vehicles. The United States Marine Corps Expeditionary Fighting Vehicle, which was taken out of service in 2011, featured a diesel engine with 12 cylinders and 1,200 horsepower (890 kW) that was produced by the German manufacturer MTU. It is possible to increase the powertrain of the EFV to 2,700 horsepower (2,000 kW) by utilizing open circuit seawater cooling when the vehicle is in the swimming position. The MTU engine is able to drive four huge water-jet exhausts, which in turn accelerate the surface-effect riding EFV vehicle to sea speeds of up to 35 knots (65 kilometers per hour). This extreme battle power setting is required for the MTU engine.

Despite the fact that the EFV prototypes displayed revolutionary performance both on land and in water, the reliability of their massively boosted powerplants never met the demanding military standards, and the vehicle was never put into service by the Marine Corps.

Water injection

German MW50, which is a combination of methanol and water

Nitrous oxide injection, often known as GM 1 in German

Forsazh is a Russian word.

Propane injection

{End Chapter 1}

Chapter 2: Allison V-1710

Over the course of World War II, the sole V-12 liquid-cooled engine that was developed in the United States and put into service was the Allison V-1710 aviation engine, which was designed and manufactured by the Allison Engine Company. There were versions of the Lockheed P-38 Lightning that were equipped with turbochargers, and these versions provided exceptional performance at high altitudes. Additionally, turbo-superchargers were installed in experimental single-engine fighters, and the results were found to be comparable.

As a result of the United States Army Air Corps' (USAAC) preference for turbochargers early on in the development program for the V-1710, less effort was spent on developing suitable mechanically driven centrifugal superchargers for the Allison V-12 design. This was due to the fact that other V-12 designs from friendly nations, such as the British Rolls-Royce Merlin, were already using these superchargers.

Generally speaking, when versions of the V-1710 with smaller dimensions or lower costs were required, they had poor performance at higher altitudes. When turbocharged, the V-1710, on the other hand, provided outstanding performance, particularly in the P-38 Lightning, which was responsible for a significant portion of the extensive production run.

General Motors' Allison Division started working on an ethylene glycol-cooled engine in 1929 in order to fulfill a requirement from the United States Air Force (USAAC) for a contemporary engine that could produce 1,000 horsepower (750 kW) and be incorporated into a new generation of streamlined bombers and fighters. In order to simplify the manufacturing process, the new design could be outfitted with a variety of propeller gearing systems and superchargers. This would enable a single production line to manufacture engines for a wide range of aircraft, including bombers and fighters.

The United States Navy (USN) had the intention of utilizing the V-1710 in the rigid airships Akron and Macon; instead, both of these vessels were fitted with Maybach VL II engines that were manufactured in Germany. In December of 1932, the United States Air Force acquired its very first V-1710 aircraft. The Great Depression slowed down the development process, and the next time the engine was put through its paces was on December 14, 1936, when it was tested in the Consolidated XA-11A testbed. On April 23, 1937, the V-1710-C6 was the first engine of any type to successfully complete the USAAC 150-hour Type Test using 1,000 horsepower (750 kW). This accomplishment was accomplished by the engine. Following that, the engine was made available to aircraft manufacturers, who chose to use it to power the prototype Curtiss XP-37s. It was the driving force behind the Lockheed P-38, Bell P-39, and Curtiss P-40, all of which were built to compete in the new pursuit competition. In response to a request from war material procurement agents in the United Kingdom to construct the P-40 under license, North American Aviation (NAA) instead suggested their own improved aircraft design, which would make use of the V-1710 in their NA-73.

The V-1710 has 12 cylinders with a bore and stroke of 5.5 by 6 in (139.7 by 152.4 mm) in 60° V format, has a capacity of 1,710.6 cubic inches (28.032 liters) that is, as compared to the compression ratio of 6.65:1.

A single overhead camshaft is used for each bank of cylinders in the valvetrain, and there are four valves employed for each cylinder.

A philosophy of modular design for aircraft powerplants was embraced by General Motors, which resulted in the engine design benefiting from the company's philosophy of built-in production and installation versatility. The engine was built around a fundamental power section, which allowed for a variety of installation needs to be satisfied. These requirements could be satisfied by installing the suitable accessories section at the back of the engine and an appropriate power output drive at the front of the engine. If the user so wished, a turbo-supercharger may be utilized.

The P-39, P-63, and Douglas XB-42 Mixmaster were all equipped with V-1710-Es. Instead of having an integral reduction gear, these aircraft had an extension shaft that drove a reduction gear and propeller that were positioned in a remote location. Close-coupled propeller reduction gears were a defining characteristic of the V-1710-F series, and they were utilized by aircraft such as the P-38, P-40, P-51A, and the North American P-82E.

The accessory end was equipped with a one- or two-speed engine-driven supercharger that might have a second stage with or without an intercooler, the ignition magnetos, and the typical selection of oil and fuel pumps, all of which were determined by the requirements of the application. Output drives