Theories — what might have happened to AirAsia plane?

As the search continues for AirAsia Flight 8501, theories on what led to the jet's disappearance are focused on stormy weather over the Java Sea.

Expert investigators could spend a year unraveling what happened to the jet — after it is found. In addition to weather, possible mechanical problems and human errors will be studied in an effort to prevent the recurrence of any problems.

Possible factors:

• A storm disabling aircraft equipment, as happened when Air France Flight 447 crashed into the Atlantic Ocean in 2009.

• A storm confusing pilots, who then lose control of the aircraft, as investigators found with Air France and with Colgan Air Flight 3407, which crashed near Buffalo in 2009.

• Some sort of catastrophic failure of the aircraft, which could explain why the pilots didn't send a distress call before colleagues on the ground lost track of it.

Airlines, manufacturers and government regulators will want to examine the jet and its voice and data recorders to learn what happened.

"Those provide the most important and crucial information," said Steve Marks, a Miami aviation lawyer, who urged officials to provide only factual updates about the search and not to speculate.

Capt. Patrick Smith, a commercial pilot who blogs about aviation at askthepilot.com, said in an e-mail interview that a seeming red flag is the stormy weather, which pilots are taught to avoid.

"Could the Airbus A320, flying between Surabaya and Singapore, have wandered inadvertently into a violent thunderstorm and suffered some kind of catastrophic malfunction or structural failure?" Smith asked. "It's possible."

He said early hunches about aviation problems are often off-base. Smith said he flew on AirAsia a few years ago and the airline seemed as professional as any other major airline.

"Headquartered in Kuala Lumpur, Malaysia, AirAsia is the largest low-fares airline in Asia and one of the biggest in the world," Smith said. "It operates about 70 aircraft, all of them A320s, on routes around Indonesia, Thailand, Malaysia and beyond."

Smith said the lack of a distress call from the pilots "likely means nothing" because communicating with ground controllers is low on the list of priorities in an emergency.

"Your priorities are to control the aircraft and deal with whatever malfunction or urgency is at hand," Smith said.

The AirAsia pilots were considered quite experienced. The captain had 20,000 flying hours, including 6,100 hours on the Airbus, AirAsia said.The first officer had 2,275 flying hours.

The A320 family of jets, which includes the A319 and A321, has a good safety record, with just 0.14 fatal accidents per million takeoffs, according to a safety study published by Boeing in August.

Sunardi, a forecaster who goes by one name at Indonesia's Meteorology and Geophysics Agency, said dense storm clouds were detected up to 44,000 feet in the area at the time.

"There could have been turbulence, lightning and vertical as well as horizontal strong winds within such clouds," Sunardi said.

Christopher Herbster, associate professor of applied meteorology at Embry-Riddle Aeronautical University in Daytona Beach, Fla., said pilots are warned about hurricane-force vertical winds in a thunderstorm that can push up and down on a plane's wings.

"Certainly one reason to fly around is risk of injury to passengers and risk of damage to the aircraft," said Herbster, who said strong storms covered the Java Sea before the AirAsia flight disappeared.

Ice buildup is another problem. even in summer storms, because the cold air at high altitudes allows water drops to freeze against an aircraft. The anvil-shaped cloud at the top of a storm is ice, while the puffy white clouds below are water, so pilots try to navigate around storm clouds in the search for blue skies, Herbster said.

"They are literally doing a slalom through thunderstorms when you get to a situation like this," Herbster said.

In the Air France crash of an A330 — a different model and larger aircraft than the AirAsia aircraft — instruments called pitot probes that measured air speed became frozen and their readings then confused the pilots, according to investigators.

Airbus replaced the pitot probes on that series of aircraft to prevent future problems, said Marks, the aviation lawyer.

Contributing: The Associated Press