Tis the season to be traveling as US airlines add 143,000 seats a day across their global networks to cope with a forecast 45.7 million passengers over the 18-day Christmas holiday period. That’s up 5.2 percent on last year and equates to an average 2.54 million passengers a day -  126,000 a day more than the same period in 2017-18 - between December 20 and January 6. Industry lobby group Airlines for America (A4A) forecasts daily passenger volumes will range from 2.1 to 2.9 million with Thursday, December 20, Friday, December 21 and Wednesday, December 26 the busiest days. Those looking for the lightest travel days are advised to book their flights on Christmas Eve, Christmas day or Saturday, January 5. The Yule travel boom comes after the busiest Thanksgiving on record. “With airfares at historic lows, travelers are choosing to fly on U.S. airlines in record numbers, especially during the busy holiday season,” A4A Vice President and Chief Economist John Heimlich. US Airlines are also working closely with the Transportation Security Administration in an attempt to keep security bottlenecks to a minimum. "Airlines are investing and work in close coordination with the TSA, including by expanding the use of biometrics and innovative screening technology and encouraging more passengers to enroll in Trusted Traveler Programs,” said A4A Vice president of security and facilitation Lauren Beyer. “These innovations make us more secure and improve the passenger experience. The security of our passengers and crew is always the industry’s top priority, especially during the busy holiday travel season.” Airlines in other markets are also girding themselves for the Christmas period. In Australia, Virgin Australia announced it had put on 1000 more flights and an additional 175,000 seats for the festive season. These include an additional 850 domestic flights and 45,000 more seats to international destinations such as New Zealand and Fiji. The Australian carrier is predicting to the 10 most popular destinations for the southern hemisphere summer holiday period will be Gold Coast, Hobart, Queenstown, Cairns, Christchurch,  Fiji, Perth, Alice Springs, Vanuatu and the Sunshine Coast. In New Zealand, however, travelers face potential disruptions as Air New Zealand continues talks with unions about threatened Christmas strikes. Read: Air New Zealand faces expanded Xmas strike threat.