GUATEMALA CITY — A joint U.S. and Guatemalan anti-narcotics aviation program is in trouble after less than a year in operation due to chronic non-payment of a key contractor by the Central American nation's government.

Helicopteros de Guatemala notified the country’s Interior Ministry in July that it would cease Guatemalan air operations used for anti-drug surveillance and interdiction.

The program’s failure raises questions about the reliability of Guatemala as a dependable partner with the United States in the war against Central American drug lords who are also deeply involved in the movement of thousands of illegal immigrants, including many unaccompanied children, to the U.S.

The Guatemalan company's U.S. partner is the Florida-based Bristow Academy. The Guatemalan government's part of the program's funding was $10 million.

Guatemalan Interior Minister Mauricio Lopez Bonilla told the Washington Examiner the contract would end but promised a new expedited bidding process to resume the program.

Guatemala is the northern-most of three Central American countries — El Salvador and Honduras are the others — that are home for most of the young children showing up at the U.S. border with Mexico.

Central American and Mexican drug lords profit on each minor by assisting coyotes, individuals who promise passage to the U.S. border. The children are taken on a perilous journey that can include sexual attacks and other abuses.

The helicopter transfer program began last year when the U.S. State Department encouraged the Guatemalan government to operate an anti-narcotic air wing rather than rely on the U.S. government.

Washington donated six upgraded Huey II helicopters, a modernized version of the Bell UH-1, to serve as Guatemala’s new anti-drug air fleet.

The Obama administration heralded the program and assisted the Guatemalan government in an award of a three-year contract to the two companies.

Guatemala’s President Otto Perez Molina and U.S. Ambassador Arnold Chacon watched from a viewing stand Oct. 8, 2013, as the six helicopters flew in formation over Guatemala City's La Aurora air base.

Perez hailed the helicopter transfer as “a vote of confidence for Guatemala from the United States,” according to Dialogo, a military magazine published by U.S. Southern Command.

As early as December 2013, however, it became clear the Interior Ministry was having trouble making the monthly payments on time, according to a knowledgeable individual who was willing to speak only on the basis of anonymity.

The Guatemalan government was three and a half months behind in its payments by June of this year.

The failure to pay on time dramatically affected the availability of the helicopter air fleet by hobbling the company’s ability to maintain an adequate inventory of spare parts, according to a second knowledgeable individual.

Only two of the six helicopters were airworthy due to lack of parts on multiple occasions, and there have been times when only one of the helicopters was airworthy.

None of the helicopters met the 120 hours of flight time required for training purposes during the past three months. The contract required training for 12 Guatemalan Air Force pilots.

Eight veteran contract pilots served as first-line pilots, trainers and mentors for the Guatemalan airmen.

“The first months were OK,” the first knowledgeable individual told the Examiner, referring to the period between September and December 2013.

“The following months, there were partial payments, then no payments at all. It could not continue like that,” the first knowledgeable individual said.

After Helicopteros de Guatemala told the Guatemalan government it would terminate the program in September 2014 on its first anniversary, additional negotiations resulted in an agreement to extend operations through Oct. 23, 2014.

Lopez told the Examiner that “with these types of payments, anything to do with the state regularly has delays,” adding that “in the contract, it is established that there can be delays in the payments, and because of that, the businesses that participate in this kind of operation have to be very strong financially.”

But the first knowledgeable individual disagreed, contending that “the contract did not say that. The payments have to be on time, not in a delay of months and months.”

A government’s reputation for late payments can take a toll on a country’s credibility, according to Jose Luis Gonzales, a lawyer and professor of political science at Francisco Marroquin University in Guatemala City.

The late government payments “not only break a promise,” Gonzales said, but also send a message that the government “is untrustworthy for any future commitment or contract.”

The U.S. Embassy in Guatemala City did not reply to the Examiner’s request for comment.