MONTREAL - An airline that provides service to Northern Canadian communities added extra flights Friday to transport passengers stranded by the shutdown of a key satellite struck by a software failure just ahead of the Thanksgiving holiday.

"We've beefed up our schedule today to make sure that we look after everybody and try to minimize the disruptions because of this," First Air vice-president Chris Ferris said Friday in an interview.

The Kanata, Ont.,-based airline cancelled 48 flights with about 1,000 passengers for safety reasons Thursday because it wasn't able to communicate with air traffic controllers or emergency responders on the ground after the Anik F2 satellite stopped transmitting.

Flights were maintained, however, to Yellowknife, Edmonton and charters to diamond mines.

Air Canada (TSX:AC.B) said it didn't suffer any disruptions.

Nav Canada said backup systems and procedures were activated to mitigate much of the impact on Canada's civil air navigation system.

Standard procedural separation used when radar is not available was put in place north of latitude 54 to keep aircraft safely separated, said spokesman John Morris. These flights, including those from Europe, were forced to switch to satellite phones or radio to communicate with air control centres and obtain weather information.

Morris said Nav Canada will be conducting a review to see if any procedural changes are required.

The satellite problem also affected long-distance phone service, cellphone data service and some Internet access in parts of the country.

Service began to be restored around 10 p.m. and was fully back to normal by 7 a.m. Friday.

Telesat said a software error that occurred during a routine manoeuvre triggered the satellite to shut down, causing many Canadians to lose communications for much of Thursday.

The Ottawa-based owner and operator of the communications spacecraft said Friday that the error appears to have been caused by a software update recently provided by the satellite manufacturer.

"It's our belief that it was that particular software load update that conflicted with other software on the spacecraft and caused it to go into safe mode," said Telesat spokesman John Flaherty.

The company said that type of anomaly is highly unusual.

Launched in 2004, the Anik F2 is one of the largest and most powerful telecommunications satellites orbiting 35,800 kilometres above the Earth.

Once the satellite put itself in "safe mode," it pointed towards the sun to charge its batteries until the repair prompted it to turn around and resume its transmissions.

The disruption or "loss of earth lock" affected services for customers including Shaw Direct TV, government agencies, and The Canadian Press news agency.

The satellite supports a variety of services including voice and data for Internet, broadcast and business customers in Canada and parts of the United States.

The blackout reminded many residents of remote communities how isolated they are and highlights the need for governments to beef up the communications infrastructure in the Far North, Ferris said.

"I think yesterday demonstrated how critical it is to basic commerce and communications in the North."

Flaherty said several customers, including Shaw Direct, were able to maintain some service because they had other satellites as well.

"Telesat has multiple satellites that cover the north so if you have the right terrestrial ground infrastructure in place...they can easily switch services from one to the other."

Options include repointing to another satellite or having a second antenna pointed at other satellites.

Former astronaut Marc Garneau, who headed the Canadian Space Agency when the satellite was launched, said Telesat's service is outstanding. However, he added that it's up to territorial and provincial governments to decide whether they want to invest in beefing up the telecommunications system or leave the role to the private sector.

"Local government need to make a decision about, whether they consider that to be as fundamental as roads, sewage and water systems," the Liberal MP said in an interview.

He said the federal government's role would be to advance technology through the space agency.

Remote northern locations were the most affected, with 10 of 33 communities served by NorthwesTel seeing disruptions from the outage.

About 20,000 subscribers were affected, including the entire population of Nunavut.

NorthwesTel has access to three satellites but is now looking into alternative capacity arrangements.

"We're look into ways that we could transfer to one of our remaining satellites just enough to restore basic service should something like this occur again," said spokeswoman Emily Younker.

Shaw Direct uses several satellites so its service was only partly affected. Bell TV uses a different satellite while Telus said its customers faced no service problems.

NorthwesTel said long distance service was disrupted in satellite communities. DSL-based Internet in Iqaluit, other data services in the Northwest Territories and Nunavut and some cable television channels were also impacted.

Bell Aliant said about 7,800 residential and business customers in northern Ontario, northern Quebec and Atlantic Canada were affected by a disruption to long distance telephone service and some TV channels.