Q: How can I tell if an international carrier is safe? —Sarah Jones, Charlotte, N.C.

A: Even if we don’t like to admit it, the act of getting on a plane involves a great deal of trust: trust in the pilots and the flight crew, in the aircraft makers, in the airline, and—ultimately—in the authorities who approved the plane to fly. Domestically, this last responsibility lies with the Federal Aviation Administration, which is known for its exacting standards. But given that there’s no single organization with the authority to enforce safety around the world, things are more complicated abroad.

The easiest rule of thumb: book on foreign airlines that operate code-share flights with U.S. partners. (Global alliances—Star Alliance, Oneworld, SkyTeam—usually involve some form of code-sharing.) Before a U.S. airline can place its passengers on a foreign carrier, it must conduct a safety review of its partner and submit the results to the FAA for approval. As an added incentive, the U.S. airline may also be liable should anything happen to its passengers on a code-share flight.

But what about the slew of new, low-cost carriers that are springing up across the globe? In Asia, their presence has expanded sevenfold in the past decade alone. They’re tempting, but how safe are they?

“Take a look at where the airline is based. That’s key,” says Mary Schiavo, a former Department of Transportation inspector general who is now an aviation lawyer and safety advocate. The International Civil Aviation Organization, an agency of the United Nations, has developed a set of guidelines to evaluate the quality of local aviation systems—the idea being that if a country has a robust civil aviation authority, its carriers will uphold high safety standards. Looking at everything from legislation to operations to airworthiness, the ICAO continuously audits 185 different countries and publishes the results online. The United States comes in well above average, earning scores of between eight and 10 (out of 10) across all categories. South Korea and Singapore both pull off straight 10’s—a strong mark in favor of carriers based in those countries. Things are less clear when a country scores in the midrange, according to Harro Ranter, president of the Aviation Safety Network, an online database: “It’s hard to tell if the local authorities are really equipped to judge the airlines in those countries.”

The FAA, meanwhile, conducts assessments of civil aviation authorities whose airlines have applied to fly into the United States. It publishes the results, delivering a verdict of either Category 1 (adheres to international standards) or Category 2 (does not adhere) for each country. Notably, both Indonesia and the Philippines (where a number of start-ups are based) have Category 2 ratings, a serious red flag for their carriers. But since the FAA only assesses certain countries, the list is far from comprehensive.

The European Commission takes an even more consumer-friendly approach, publishing a blacklist of airlines that are banned from entering member states, based on aircraft inspections, among other things. Nearly all Filipino and Indonesian carriers are on the list, along with airlines from 16 African countries. (“Don’t fly an African carrier unless it’s a well-known airline from a developed nation,” Schiavo advises.) But again, the list is selective: an airline’s exclusion is not a sign of approval.

Travelers can also cross-check a carrier with the International Air Transport Association; the trade group maintains a database of those that meet its safety standards—though many budget airlines don’t bother to go through the audit. The age of an airline’s fleet can also be revealing. Schiavo notes that budget carriers in India are still hit or miss. The ones that often rise to the top: those with new aircraft. “When you buy a plane from a major manufacturer, you usually get pilot training,” Schiavo says. (Good pilots make for safer flights.) But when in doubt, stick with a carrier you already know and trust.

By the Numbers

700: The percent increase in routes of low-cost Asian carriers—from 100 to nearly 800—over the past decade.

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