Interjet has become the largest domestic mainline carrier in Mexico in terms of enplanements, although Aeromexico’s network remains by far the most dominant courtesy of its regional operation, Aeromexico Connect, new data from the country’s transport ministry show.

Interjet’s passenger traffic has blossomed since its launch in 2005, particularly since Mexicana de Aviacion declared bankruptcy and ceased operations in 2010; Interjet’s enplanements grew 58% in 2011 alone compared to the previous year.

Rival low fare carrier Volaris also has grown rapidly since its started operations in 2005, and in 2011 posted a 27% year-on-year improvement in traffic, according to data released this month by the Secretaria de Comunicaciones y Transportes (SCT).

These data show that Interjet has outpaced Aeromexico to become the country’s largest domestic mainline operator in terms of enplanements, the metric the SCT uses for its analysis. Interjet’s 2011 domestic enplanements rose to 6.3 million, compared with Aeromexico’s enplanements, which grew 19% to 5 million.

Aeromexico Connect, however, adds a further 5.2 million enplanements to Aeromexico’s systemwide operations.

Volaris has become Mexico’s third-largest domestic mainline operator, with 4.6 million domestic enplanements in 2011, according to the SCT.

The domestic Mexican market grew by 4% in 2011, the first full year without Mexicana and its Click regional subsidiary, which combined had been the country’s largest operator. But the demise of Click seems to have had the greater effect, with regional enplanements in 2011 falling 27% while domestic mainline enplanements grew 22%.

While Interjet may have wrestled some domestic market share from Aeromexico, the largest operator continues to benefit from Mexicana’s departure from the long-haul sector, a fact illustrated in the 12% rise in Aeromexico’s international enplanements to 3.2 million passengers.

Aeromexico is the largest Mexican international carrier, with two-thirds more traffic than its closet competitor, Volaris. Yet, Volaris’ international market share is rising rapidly, with a 190% year-on-year increase in 2011 enplanements to 1.5 million.

Mexican carriers’ percentage of the international market, however, has declined since Mexicana ceased operations, with enplanements falling from 63% of the market to 60%. Foreign carriers saw market share grow correspondingly, from 37% of the market in 2010 to 41% in 2011. The market overall grew 4% to 51 million enplanements, SCT data show.

Most of the foreign gains went to U.S. carriers, with their passenger traffic rising 11% in 2011 to 15 million enplanements. But Central and South American airlines saw the largest percentage growth in the time period, with passenger traffic rising 37% to 2 million enplanements, the data show.

The passenger market between Mexico and Central and South America is one-tenth the size of the Mexico-U.S. market, according to the SCT data.