An effort to fly a glider into the stratosphere is rapidly approaching a crossroads.

A lack of Sierra Wave during the month of April has left the crew of the Perlan II with a choice — remain in Minden to complete testing, or take the effort to South America.

The ultimate goal is to be the first glider to fly to 90,000 feet, but on Saturday, crewmembers were watching the sky to see if they would be able to make a 13th test flight.

In order to be ready for the big climb, the aircraft must complete 20 test runs and spend at least two hours above 30,000 feet.

So far the Perlan II has yet to make it to that height, according to Airbus Group Senior Vice President Ken McKenzie.

Key to the decision is whether there is sufficient technical support for the project in South America.

Airbus Chief Executive Officer Tom Enders visited Minden on Saturday for an update on the project. Airbus is sponsoring the project.

McKenzie said the project was funded for two years, so the decision in June could be critical.

Wave conditions coming off the Andes in Argentina are anticipated to propel the Perlan II to record-breaking altitudes.

While the first season in South America is not anticipated to include a record flight, McKenzie said that if conditions are right, the team could make an attempt.

Glider pilot and Perlan Project Manager Morgan Sandercock pointed out that not much is known about the edge of the atmosphere, where the Perlan will fly.

“The glider will explore a part of the atmosphere people have never been,” he said. Information gathered during the flight could be a benefit to meteorologists.

He said another benefit is the inspiration to children to become the next generation of engineers.

In order to survive stratospheric conditions, the Perlan II has a sealed cabin. Pilots Steve Fossett and Einar Enevoldson broke an altitude record of 50,722 feet on Aug. 30, 2006. But they found controlling the aircraft in pressure suits was difficult.

Morgan pointed out that the sealed cabin will allow pilots to avoid the bulky and heavy suits.

The aircraft also has a parachute mounted behind the cabin in case of emergency. While a record-breaking flight is only expected to take 6 hours, everything is engineered to last eight hours.

One issue still to be worked out is controlling the cabin temperature. In gliders where the cabin is open, temperatures at upper altitudes can drop to well below freezing. However, Morgan said the Perlan cabin has had temperatures of around 100 degrees.

Chief Pilot Jim Payne is a retired U.S. Air Force pilot who moved to Minden three years ago to fly gliders in the Sierra Wave.

Wife Jackie, who is also on the team, said Payne broke a speed record in his own glider as recently as March, but that April hasn’t been that good for flying.

Payne meanwhile was outside watching the sky for some hint that the Perlan could fly on Saturday.

“It started raining again,” he said.

Fair weather is forecast for this week, which will give the team ample opportunities to get the Perlan into the air.