one the very last SWISSAIR flights were "smoking on board" was permitted!

After years of debate over health concerns, Congressional action in 1987 led to a ban on inflight smoking. In 1988, airlines based in the United States banned smoking on domestic flights of less than two hours, which was extended to domestic flights of less than six hours in February 1990, and to all domestic and international flights in 2000. The 1990 ban applied to the passengers and the cabin of the aircraft, but not the flight deck; pilots were allowed to continue smoking after the 1990 ban due to concerns over potential flight safety issues caused by nicotine withdrawal in chronic smokers. Despite a prohibition of smoking, the US Federal Aviation Administration regulations mandate that functioning ashtrays be conspicuously located on the doors of all airplane bathrooms. This is because there must be a safe place to dispose of a lit cigarette if someone violates the nosmoking rule.[24]

In 1990, Air Canada adopted a nonsmoking policy on all its routes. In 1994, Canada was the first country to ban smoking on all flights operated by Canadian carriers, which also covered charter flights, but not foreign airlines flying to Canada. It had previously banned smoking on commercial domestic flights in Canada and international flights of less than six hours, which obviously did not cover the Japan route. Canadian Airlines had opposed the blanket ban, saying it would put the airline at a competitive disadvantage especially on the lucrative Japan route. It said it would lose millions of dollars in business from smoking passengers. It estimated it would lose $22 million in annual revenues on its 14 flights a week to Japan. It said that three quarters of its passengers on the Japan route were Japanese and that 60% of them smoked.

In March 1995, the United States, Canada, and Australia agreed to ban smoking on international flights traveling between those countries.

Japan

Despite a prohibition on smoking, many aircraft lavatories contain an ashtray, to minimize the risks with a noncompliant passenger putting a lit cigarette in the toilet or trash receptacle instead.
In April 1988, Japan Airlines (JAL) was the first Japanese airline to introduce a smoking ban on domestic flights of less than one hour, which was extended in October 1990 to flights of less than two hours. In 1998, All Nippon Airways and JAL banned smoking on all domestic flights, which covered more than 50% of Japanese domestic travelers. These airlines extended the ban to international flights in March 1999, among the last airlines to ban smoking on international flights. Japan Tobacco lobbied the airlines to reconsider the ban, noting that smoking was earlier banned on all flights of 22 foreign airlines using Japanese airports and that with the smoking ban by the two major Japanese airlines more than 80% of seats on international flights departing from Japan would be nonsmoking.

Europe
In 1986, flag carrier of Turkey, Turkish Airlines banned inflight smoking for all domestic flights and international flights of less than six hours. The airline banned all inflight smoking in 1999.

In 1988, SAS made domestic flights in Sweden and Norway nonsmoking and in 1989, the policy was expanded to domestic flights in Denmark and flights between the Nordic countries. In 1996, SAS flights to the Benelux countries, France, Germany, Switzerland, Austria and the United Kingdom became nonsmoking. In 1997 SAS banned smoking on all flights. Also in 1997, the European Union banned smoking on flights in member states. Air France, the French staterun carrier, did not allow inflight smoking from November 2000.

United Kingdom
Aurigny Air Services which is based in the Bailiwick of Guernsey became the first airline in the world to ban smoking entirely on its flights, in July 1977. The first United Kingdom airline to ban smoking was Loganair which banned smoking on all flights in 1980. The Flag carrier British Airways introduced a trial ban on smoking on some flights in 1990 and banned smoking on all flights in 1998. Virgin Atlantic banned smoking on all flights in 1995.

Other
Australia banned smoking on domestic flights in December 1987, on international flights within Australian airspace in 1990, and in 1996 banned smoking on all Australian international flights.

Cuba’s stateowned Cubana banned smoking on international flights in 2014.

China banned smoking on domestic flights in 1983. In 1993, China announced that all flights would be smokefree by January 1995. Both 1983 and 1993 bans only applied to passengers smoking in the cabin, while pilots were allowed to smoke in the cockpit. A total ban of inflight smoking was announced in October 2017, and individual airlines were given two more years before a cockpit ban was to take effect; however, this concession was scrapped in January 2019 following incidents that triggered safety concerns.