Question: How long does it take for a bullet fired into the air to come down?

Celebratory gunfire

Celebratory gunfire (also called aerial firing or happy fire) is the shooting of a firearm into the air in celebration.  It is culturally accepted in parts of the Balkans, the Middle East, the Central Asian region of Afghanistan, and the South Asian region of Pakistan.  In regions such as Puerto Rico and the contiguous United States any practice of it is illegal, especially on holidays like New Year's Eve.[1]
Common occasions for celebratory gunfire include New Year's Day as well as religious holidays such as Eid.[2] The practice may result in random death and injury from stray bullets. Property damage is sometimes another result of celebratory gunfire; shattered windows and damaged roofs are often found after such celebrations.[3]
Falling-bullet injuries

Bullets fired into the air usually fall back with terminal velocities much lower than their muzzle velocity when they leave the barrel of a firearm.  Nevertheless, people can be injured, sometimes fatally, when bullets discharged into the air fall back down to the ground.  Bullets fired at angles less than vertical are more dangerous as the bullet maintains its angular ballistic trajectory and is far less likely to engage in tumbling motion; it therefore travels at speeds much higher than a bullet in free fall.
A study by the U.S. Centers for Disease Control and Prevention (CDC) found that 80% of celebratory gunfire-related injuries are to the head, feet, and shoulders.[4]  In Puerto Rico, about two people die and about 25 more are injured each year from celebratory gunfire on New Year's Eve, the CDC says.[5] Between the years 1985 and 1992, doctors at the King/Drew Medical Center in Los Angeles, California, treated some 118 people for random falling-bullet injuries. Thirty-eight of them died.[6]
Firearms expert Julian Hatcher studied falling bullets in the 1920s and calculated that .30 caliber rounds reach terminal velocities of 90m/s(300feet per second or 186miles per hour).[7]
A bullet traveling at only 61m/s(200feet per second) to 100m/s(330feet per second) can penetrate human skin.[8]
In 2005, the International Action Network on Small Arms (IANSA) ran education campaigns on the dangers of celebratory gunfire in Serbia and Montenegro.[9]
In Serbia, the campaign slogan was "every bullet that is fired up, must come down."[10]
Property damage
Bullets often lodge in roofs, causing minor damage that requires repair in most cases. Normally, the bullet will penetrate the roof surface through to the roof deck, leaving a hole where water may run into the building and cause a leak.[11]
Trends
Philippine Health Secretary Francisco Duque III noted the drop in stray bullet injuries, in that country, during the 2005 year-end holiday period – from 33 cases to 19.[12]
The number of complaints regarding random shooting in Dallas, Texas, on New Year's Eve declined from approximately 1,000 in 1999 to 800 each in 2001 and 2002.[3]
In early 2008, increased partisanship in Lebanon led to the practice of firing celebratory gunfire in support when politicians appeared on local television, leading to multiple deaths and to calls from these leaders to end the practice.[13]
Notable incidents

Europe
On 7 January 2008, at about 9:30 pm, a Montenegro Airlines Fokker 100 (4O-AOK) was shot at while landing at Podgorica Airport. A routine inspection of the aircraft led to the discovery of a bullet hole in the aircraft's tail. The aircraft was carrying 20 passengers, but no one was injured. The reason for the incident is unknown; however, reports indicate that it may have been an inadvertent result of guns being fired during celebrations for Orthodox Christmas.
January 1, 2005: A stray bullet hit a young girl during New Year celebrations in the central square of downtown Skopje, Macedonia. She died two days later. This incident led to the 2006 IANSA awareness campaign in that country.[2]
October 12, 2003: Wedding guests in Belgrade, Serbia mistakenly shot down a small aircraft.[14]
Middle East
April 6, 2014: A 20-year-old pregnant mother of two, Wadia Baidawi, was struck in the head and killed by a stray bullet from her neighbor’s wedding in Sidon, Lebanon.[15]
November 21, 2012: Following a cease-fire ending fighting with Israel, celebratory gunfire in the Gaza Strip killed a man and wounded three others.[16]
October 30, 2012: Twenty-three people were electrocuted after celebratory gunfire brought down a power cable during a wedding party in eastern Saudi Arabia.[17]
August 2012: A Kuwaiti bridegroom was killed when a friend of his accidentally shot him as he charged his gun to fire into the air in celebration.[18]
August 2010: 2 people were killed and 13 were injured in Jordan, as part of the yearly celebration of the announcement of the result of Tawjihi.[19]
July 29, 2007: At least four people were killed and 17 others wounded by celebratory gunfire in the capital city of Baghdad, Iraq, following the victory of the national football team in the AFC Asian Cup.[20][21] Celebratory gunfire occurred despite warnings issued by Iraqi security forces and the country's leading Shiite cleric, Grand Ayatollah Ali al-Sistani, who forbade the gunfire with a religious fatwā.[22]
July 22, 2003: More than 20 people were killed in Iraq from celebratory gunfire following the deaths of Saddam Hussein's sons Uday and Qusay in 2003.[13]
South America
December 25, 2012: A stray bullet killed a three-year-old girl in Asunción, Paraguay.[23]
South Asia
November 16, 2016: A self-proclaimed godwoman and her private guards went on a celebratory shooting spree at a wedding in Haryana's Karnal town in India, killing the groom's aunt and leaving three of his relatives critically wounded.[24]
June 6, 2013: a 42-year-old Pakistani woman was killed by a stray bullet from celebratory gunfire. The gunfire was attributed to celebrations for the election of Pakistan's prime minister Newaz Sharif. Her 19-year-old niece was also hit, and rushed to hospital in critical condition.[25]
February 25, 2007: Five people were killed by stray bullets fired at a kite festival in Lahore, Pakistan, including a six-year-old schoolboy who was struck in the head near his home in the city's Mazang area.[26]
December 1859: An autopsy showed that a native servant in India, who suddenly fell dead for no apparent reason, was mortally wounded from a bullet fired from a distance too far for the shot to be heard. The falling bullet had sufficient energy to pass through the victim's shoulder, a rib, a lung, his heart and his diaphragm.[27]
United States
July 1, 2017: A 13-year-old boy, Noah Inman, was struck in his head and killed while playing basketball in the street.[28]
January 1, 2017: Armando Martinez, a Texas state Representative, was wounded in the head by a stray bullet during a New Year's celebration.[29]
January 1, 2015: A 43-year-old man, Javier Suarez Rivera, was struck in his head and killed while watching fireworks with his family in Houston.[30][31]
July 4, 2013: A 7-year-old boy, Brendon Mackey, was struck in the top of his head and killed while walking with his father shortly before 9 p.m. amid a large crowd prior to the fireworks display over the Swift Creek Reservoir, outside Richmond, Virginia.[32]
January 1, 2013: A 10-year-old girl, Aaliyah Boyer, collapsed after being struck in the back of the head while watching the neighborhood fireworks in Eklton, Maryland. She died two days later of her injuries.[33]
July 4, 2012: A 34-year-old woman, Michelle Packard, was struck in the head and killed while watching the fireworks with her family. The police believe the shot could have come from a mile away.[34]
January 1, 2010: A four-year-old boy, Marquel Peters, was struck by a bullet and killed inside his church The Church of God of Prophecy in Decatur, GA. It is presumed the bullet may have penetrated the roof of the church around 12:20AM.[35]
In March 2008, Chef Paul Prudhomme was grazed by a .22-caliber stray bullet while catering the Zurich Classic of New Orleans golf tournament. He at first thought a bee had stung his arm, required no serious medical attention, and within five minutes was back to cooking for the golf tournament. It was thought to have been a falling bullet.
December 28, 2005: A 23-year-old U.S. Army private on leave after basic training fired a 9mm pistol into the air in celebration with friends, according to police, one of the bullets came through a fifth-floor apartment window in the New York City borough of Queens, striking a 28-year-old mother of two in the eye. Her husband found her lifeless body moments later. The shooter had been drinking the night before and turned himself in to police the next morning when he heard the news. He was charged with second-degree manslaughter and weapons-related crimes,[36][37] and was later found guilty and sentenced to 4 to 12 years in prison.[38]
June 14, 1999: Arizona, A 14-year-old girl, Shannon Smith, was struck on the top of her head by a bullet and killed while in the backyard of her home.[39]  This incident resulted in Arizona enacting "Shannon's Law" in 2000, that made the discharge of a firearm into the air illegal.
December 31, 1994: Amy Silberman, a tourist from Boston, was killed by a falling bullet from celebratory firing while walking on the Riverwalk in the French Quarter of New Orleans, Louisiana. The Police Department there has been striving to educate the public on the danger since then, frequently making arrests for firing into the air.[40]
July 4, 1950: Bernard Doyle was killed in his seat while attending a New York Giants game at the Polo Grounds. The bullet was determined to have been fired by Robert Peebles, a juvenile, from an apartment building some distance away on Coogan's Bluff, presumably in celebration of Independence Day.[41][42][43]
Penalties
In the Republic of Macedonia, a person found guilty of firing off a gun during celebrations faces a jail sentence of up to ten years.[2]
In Italy, under the art.703 of the Penal Code(Dangerous lightings and explosions), a person found guilty of firing off, without authority's permission, a gun in an inhabited place or near it, is sentenced to a fine up to 103 Euros, while if he commit the act in a place with more person than usual is sentenced to up a month in prison. The offence include also fireworks, rockets, flaming aerostats and, in general, "dangerous lightings and explosions".[44]
In Pakistan, section 144 of the law is imposed to prevent aerial firing during celebrations if harm is caused, and an FIR may be registered against a person who does so. However, many cases of aerial firing go unreported.[1]
In the United States, crime classifications vary from a misdemeanor to a felony in different states:
In Arizona, firing a gun into the air was raised from a misdemeanor to a felony by Shannon's law, in response to the death of a 14-year-old from a stray bullet in 1999.[45]
In California, discharging a firearm into the air is a felony punishable by three years in state prison. If the stray bullet kills someone, the shooter can be charged with murder.[46][47]
In Minnesota, it is illegal to discharge a firearm over a cemetery, or at or in a public transit vehicle. Additionally, local governments may regulate the discharge of a weapon within their jurisdictions.[45]
In Ohio, discharging a firearm or a deadly weapon in a public place is classified as disorderly conduct, a Class B misdemeanor, punishable by up to 180 days in jail and a fine of up to $2,000.[48]
In Texas, random gunfire is a Class A misdemeanor, punishable by a maximum one year in jail and $4,000 fine. Anyone who injures or kills someone with a stray bullet could face more serious felony charges.[3]
In Wisconsin, criminal charges for this type of offense range from "endangering safety by use of a dangerous weapon" to "reckless homicide" in the event of a death, with penalties ranging from nine months to 25 years in prison."[5]
Cultural references
The non-fiction U.S. cable television program MythBusters on the Discovery Channel covered this topic in Episode 50: "Bullets Fired Up" (original airdate: April 19, 2006). Special-effects experts Adam Savage and Jamie Hyneman conducted a series of experiments to answer the question: "Can celebratory gunfire kill when the bullets fall back to earth?"
Using pig carcasses, they worked out the terminal velocity of a falling bullet and had a mixed result, answering the question with all three of the show's possible outcomes: Confirmed, Plausible and Busted.[49] They tested falling bullets by firing them from both a handgun and a rifle, by firing them from an air gun designed to propel them at terminal velocity, and by dropping them in the desert from an instrumented balloon.
They found that while bullets traveling on a perfectly vertical trajectory tumble on the way down, creating turbulence that reduces terminal velocity below that which would kill, it was very difficult to fire a bullet in a near-ideal vertical trajectory. In practice, bullets were likely to remain spin-stabilized on a ballistic trajectory and fall at a potentially lethal terminal velocity. They also verified cases of actual deaths from falling bullets.[50]
See also

Feu de joie
21-gun salute


Further reading
"Falling bullets: terminal velocities and penetration studies", by L. C. Haag, Wound Ballistics Conference, April 1994, Sacramento, California.


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