TOKYO (AFP) - Japan Airlines (JAL) said on Monday that its net profit in the nine months to December slipped 3.7 per cent to US$1.52 billion (S$1.9 billion), but the carrier boosted its full-year profit estimate.

JAL, which re-listed its shares in Tokyo last year after a high-profile bankruptcy restructuring, said it booked a 140.64 billion yen (S$1.9 billion) net profit in the nine-month period, while upping its profit estimate for the year to March to 163 billion yen from an earlier 140 billion yen forecast.

Sales over the nine-month period were up 3.6 percent at 942.04 billion yen.

JAL credited the upward full-year profit revision to an expected income boost "from new products and services as our business in Europe and the United States as well as Southeast Asia are performing well, despite concerns over the suspension in service of the Boeing 787".

JAL and rival All Nippon Airways (ANA) have been hit by the worldwide grounding of Boeing's Dreamliner following an emergency landing by an ANA domestic flight earlier this month.

The carriers, major Dreamliner customers with over 100 combined orders, have each cut hundreds of flights that affected tens of thousands of passengers.

Aviation regulators are focusing on the next-generation plane's lithium-ion battery system as the cause of a problem that forced an ANA flight to make an emergency landing in mid-January, setting off probes and the international no-fly order.

US regulators have said they will not allow the 787 to fly again until they are sure the problems around the battery system are fixed.

The Japanese carriers have also been affected by a row between Tokyo and Beijing over sovereignty of a group of islands in the East China Sea, which triggered anti-Japan rallies across China and a consumer boycott of Japanese