Traveling faster than the speed of sound requires special aircraft to achieve. Air Force Captain Charles E. “Chuck” Yeager was the first to do it in 1947.
Gun ammunition typically travels at speeds above the speed of sound, producing loud noise known as sonic cracks. But some ammunition is purposefully subsonic.
1. Subsonic
The speed of sound in air is approximately 1100 feet per second (fps), depending on atmospheric conditions and altitude. Anything traveling faster than this threshold is considered supersonic while anything slower is considered subsonic – most target and defensive ammunition is designed for subsonic operation.
Shooters might choose subsonic ammunition for various reasons, the primary being to avoid the audible “crack” caused by breaking through the sound barrier; this audible noise can be quite bothersome to those sensitive to firearm noise and disturbing for those sensitive. Furthermore, using suppressors with subsonic ammunition will significantly decrease noise production.
Subsonic ammunition provides many benefits over supersonic rounds, one being its reduced recoil. This can be especially advantageous to new shooters or those seeking a gentler experience when shooting, such as using suppressors for noise-sensitive environments or concealed carry purposes.
Manufacturers typically increase bullet weight and decrease overall velocity to make subsonic ammunition, in order to ensure more accurate shooting at their target. Sometimes a round can even naturally become subsonic due to cartridge and bullet design; an example would be traditional American military 45 ACP ammo with its heavier bullet that travels at only 850fps is automatically subsonic.
Subsonic or supersonic ammunition should present no major problems when shooting them, though subsonic ammunition could damage suppressor baffles if fired through one. Therefore, before taking it out on the range with subsonic loads it should always be tested with specific loads first to see how they behave and test suppressors accordingly. Furthermore, its lower velocity could cause instability to set in that could prevent proper feeding into barrel and result in malfunction.
2. Transonic
As a projectile approaches the speed of sound it begins interacting with its surrounding air and creating transonic flow – an area in the atmosphere where air moves around it without creating shockwaves at slower speeds like normal.
As the bullet travels through this region of atmosphere it may become unstable, becoming less efficient at cutting through airflow and creating drag compared to subsonic speeds. This effect is made even worse by different barrel twist rates; thus prompting Bryan Litz from Applied Ballistics to conduct extensive research on how different barrel twist rates influence bullet performance in both supersonic and transonic zones.
As it passes through the transonic zone, a bullet will also experience increased air turbulence that causes it to pitch and yaw violently, destabilizing it further and increasing drag significantly; its BC will consequently drop significantly as a result.
An inaccurate long range bullet has no way of cutting through air effectively and becomes inert, and can often hit something solid like rocks or trees before stopping again – all this results in inaccurate shots.
Once a bullet leaves the transonic zone, its velocity will increase again; but returning into this region can pose additional difficulties and lessen accuracy, as it must once more battle against turbulence’s effects and will suffer even greater accuracy losses.
Aircraft that travel at speeds greater than the speed of sound are generally known as supersonic aircraft. While the exact definition varies with atmospheric pressure and temperature conditions, most aircraft should be capable of reaching Mach 1 speeds or faster. Ernst Mach first described this phenomenon; hence its naming as Ernst Mach’s Boom.
3. Supersonic
When an object travels faster than the speed of sound, it produces a shockwave known as a sonic boom which may create vibrations in nearby structures that cause lasting damage.
The speed of sound varies with temperature and pressure; in air at 20 degrees Celsius with sea-level pressure, its speed is 343.2 metres per second (1,125 feet per second, 768 miles per hour or 667 knots). Aircraft traveling faster than this are known as supersonic aircraft, one of four “regimes of flight” that also include subsonic, transonic, supersonic and hypersonic flight regimes.
Sonic booms occur when an aircraft or missile travels at supersonic speeds through the atmosphere, producing a very loud noise that can destroy surrounding structures and cause serious injury or damage, thus prompting the FAA to ban most overland supersonic flights in 1973.
Chuck Yeager of the US Air Force became the first pilot ever to fly a jet beyond the speed of sound in 1947. The flight took place aboard a heavily modified Bell X-1 fitted with experimental equipment designed to combat vibrations caused by supersonic speeds.
On October 14, 1947, Yeager’s X-1 broke through the sound barrier, becoming history as the first man ever to travel supersonic. To ensure his own survival during his flight – vibrations can make one feel disoriented or discombobulated during such flights – special training was required in order for him to survive it safely.
Supersonic travel offers many advantages beyond speed; for instance, London and New York City can be reached in under three hours by supersonic airliner. Furthermore, new company Boom is working on developing an ultrafast jet that could reach Mach 5, which would exceed five times the speed of sound.
Modern firearm ammunition is typically supersonic, with rifle projectiles often travelling at speeds nearing or exceeding Mach 3 and black powder musket rounds even being loaded to subsonic levels by using jacketed ammunition in combination with longer barrels – this allows the bullet to gain greater velocity by traveling farther down the barrel; its exact velocity also depends on factors like cartridge type and muzzle velocity.
4. Transonic + Supersonic
Supersonic describes speeds greater than those associated with sound waves traveling through air. As objects travel faster than this limit, they create loud sonic booms and shockwaves. Modern firearm bullets are considered supersonic; its name comes from Latin words meaning “above and beyond sound”.
There are four “regimes of flight”, from subsonic through hypersonic flight. Anything over 768 miles an hour (1.225 km/h in dry air at sea level) is considered supersonic flight.
At supersonic speeds, an aircraft experiences several unique aerodynamic effects compared to subsonic flight. Most significantly, its center of lift shifts back, creating more nose-heaviness and necessitating more thrust from its pilot in order to maintain Gs levels at their original levels. This effect occurs because airflow over its wings becomes disturbed at such high speeds causing shockwaves which push back against them causing greater nose-heaviness than subsonic flight would allow.
Another effect is an abrupt increase in drag. This occurs because supersonic speeds move into areas of denser air than was experienced at lower speeds, thus increasing pressure and temperature, leading to greater drag resistance from your aircraft and forcing more resistance through it into your flight path. Many have found supersonic flights challenging due to this increase.
Although traveling at supersonic speeds presents some unique challenges, there can be numerous advantages associated with supersonic flight. For instance, this would enable passengers to travel from London to New York in under two hours if there were commercial airplanes capable of flying consistently at supersonic speeds between them. Although commercial airplanes currently can’t do this reliably yet due to technological limitations, advances could one day allow this possibility. Although the exact speed at which an aircraft flies supersonic depends on several factors such as atmospheric conditions and altitude – hence there being no single definition for supersonic flight – though on average this would likely average out around Mach 0.8 which is comparable with rifle bullet travel speeds.