Supersonic Flight

**Supersonic Flight**, also known as the ability to go faster than sound in level flight, is a dream for all flight engineers of the New World, except for Japan and the Ravernal Empire, who have already achieved this goal, both by scientific and magical means. In addition to having gaining a great advantage in air power during war, it can also be seen as an advantage to long-distance travel.

## Overview

The speed of sound is roughly measured at sea level to be 767 mph or 1,235 km/h. This is also known as Mach 1. Exceeding this speed would cause an object to break the sound barrier, which will create a huge amount of aerodynamic drag behind the object, and a vacuum as well. When air rushes in to fill that void caused by the vacuum, a huge detonation of sound will be produced, which is called a sonic boom. The object must have the correct aerodynamics to deal with the increasing drag, stress and friction caused by sustained supersonic flight. Furthermore, it must also have enough propulsion to reach and exceed the speed of sound.

On Earth, in 1947, U.S. test pilot Chuck Yeager became the first man to break the sound barrier in level flight in the Bell X-1, achieving a speed of Mach 1.05. In the New World, the Ravernal Empire's jets were said to be the equal of supersonic jets of the 1970's.

### Supercruise

**Supercruise** is sustained supersonic flight of a supersonic aircraft with a useful cargo, passenger, or weapons load without using afterburner (also known as "reheat"). Many supersonic military aircraft are not capable of supercruise and can only maintain Mach 1+ flight in short bursts with afterburners. Aircraft such as the SR-71 Blackbird are designed to cruise at supersonic speed with afterburners enabled.

Some 4th generation fighter jets are technically capable of supercruise, but only at high altitudes and in a clean configuration. For an aircraft to be deemed capable of true supercruise, it must be able to carry a normal load for an extended distance without diving or using an afterburner. Planes marketed as featuring supercruise usually have the ability to carry a combat load at low to medium altitudes; being able to break Mach 1 without afterburner does not necessarily show supercruise ability. For example, the Federation of American Scientists defined supercruise as "the ability to cruise at speeds of one and a half times the speed of sound or greater without the use of afterburner for extended periods in combat configuration" in discussing the F-22.

One of the best-known examples of an aircraft capable of supercruise was Concorde. Due to its long service as a commercial airliner, Concorde holds the record for the most time spent supersonic; more than all other aircraft combined

## Supersonic Flight in the New World

### Third Civilization and Outside the Civilized Areas

Wyverns and other flying mounts used by the various air forces of this area, will never break the sound barrier. Even when diving at the enemy, due to the exposed rider and the living beast, the speeds attained do not even come close. During an air show in Japan, the ambassadors for the Qua-Toyne Principality and the Quila Kingdom were astounded at hearing that the F-15J could reach speeds of over 800 kph and even more than twice the speed of sound.

### Second Civilization

Mu's best fighter, the Marin, is a propeller-driven biplane, and is not suited for high-speed subsonic flight, let alone supersonic. The double-wings create too much drag and the propeller itself will hit the sound barrier first, causing small shockwaves that will disrupt the aircraft's stability, making it uncontrollable. Furthermore, the entire air-frame is too fragile and will break apart under the stress. The Mu engineers were also shocked to learn that Japan already had supersonic aircraft.

After deciding to follow Japan's lead and move away from magic, Mu engineers have gained the blueprints of one of Japan's first jet during World War 2. However, they would have to learn the principles of jet propulsion and advanced aerodynamics by themselves. Whether or not they will produce a supersonic aircraft in the near future is up for debate.

### Gra Valkas Empire

Like Mu, the Gra Valkas also had propeller-driven aircraft like the Antares. These are more advanced monoplanes with powerful engines, making them 200 mph faster than the Marin. However, they still suffer the same problems as the Mu aircraft and will never reach supersonic flight, due to the drag caused by their straight-wings and their propellers causing instability as they reach the sound barrier.

Since the Gra Valkas have abandoned research on jet engines due to the high research and development cost, it is unlikely that the Empire will achieve supersonic flight in the near future.

### First Civilization

Despite inheriting the many relics of the Ravernal Empire, the Holy Milishial Empire has yet to achieve supersonic flight. Their best aircraft, the Alpha-3 Fighter and the Floating Ship of the Heavens Type 35, are powered by Chant Powered, Light Magic-Compressed Air Discharge Engines. However, these are poor imitations that were reverse-engineered from the original engines developed by the Ravernal Empire. They have very poor thrust, compression ratio, fuel efficiency and acceleration. As a result, they cannot even outperform the Antares, nor reach the speed of sound. Furthermore, since the engineers seem to have self-taught themselves on basic aerodynamics, they are not very knowledgeable about the effects on a plane during faster-than-sound flight.

Milishial engineers have begun theorizing the feasibility of swept wings during supersonic flight, and were shocked to see the swept wings of the Japanese combat aircraft. Like Mu, the Holy Empire's engineers are looking toward Japan's aircraft as templates.

### Japan

Hailing from the early 21st century, Japan already possesses supersonic jets and high-speed aircraft and have mastered all the principles needed to achieve those kinds of speed. Currently, they are developing the next generation of aircraft that is able to super-cruise, the ability to fly at supersonic speeds without the use of fuel-hungry afterburner.