WASHINGTON — A high-altitude test of the Orion deep-space capsule’s launch abort system could be delayed two years to accommodate the tighter program budgets anticipated by NASA and Orion prime contractor Lockheed Martin.

NASA has yet to set a firm date for the high-altitude test, which is intended to demonstrate that Orion’s launch abort system — which performed well in a 2010 pad abort simulation at White Sands Missile Range in New Mexico — can propel the capsule to safety if its Space Launch System (SLS) heavy-lift rocket fails midflight.

Jose Ortiz, NASA’s lead systems engineer for the Orion launch abort system at the agency’s Langley Research Center in Hampton, Va., told Space News in a June 21 email that the high-altitude abort test “may move to fiscal year 2018” as “part of a budget proposal that is still being worked.”

That message has reached Denver-based Lockheed Martin Space Systems, which had been planning for a 2015 abort test as recently as March. “Because of budget constraints, or the budgets we’ve been given to plan to, I think that high-altitude abort is now after 2017,” John Karas, Lockheed Martin vice president and general manager of human spaceflight, said in a June 19 interview here.

NASA officials have been warning since last year that work on Orion would be slowed to keep pace with the development of SLS and its launch infrastructure. The agency has proposed trimming Orion’s $1.2 billion budget back to $1 billion for 2013.With the high-altitude abort test facing at least a budget-driven delay, the Langley team has proposed conducting one or more less-expensive tests in its place. Ortiz said conducting a hot-fire test in 2015 or 2016 would “keep the [launch abort system] project moving forward and help alleviate risk.”

NASA’s plan for the high-altitude abort test, known officially as Ascent Abort 2, calls for launching an Orion mockup and its top-mounted abort system from Cape Canaveral, Fla., on a trajectory simulating an in-flight abort scenario. The flight test would be powered by a special abort-test booster assembled by Dulles, Va.-based Orbital Sciences Corp. from surplus U.S. Air Force solid-rocket motors.

The high-altitude abort is one of two Orion flight tests NASA had been planning to conduct prior to using SLS to send an empty Orion around the Moon in 2017 and repeating the mission in 2021 with a crew onboard.

Karas said Exploration Flight Test 1 — the first orbital launch of an unmanned Orion — remains on schedule for 2014. NASA added $375 million to Lockheed Martin’s Orion contract in December for the test flight, which will be launched by a United Launch Alliance Delta 4 rocket.

NASA announced June 21 that U.S. Sen. Bill Nelson (D-Fla.) and NASA Deputy Administrator Lori Garver, among others, would be on hand July 2 to mark the arrival of NASA’s first space-bound Orion capsule at Kennedy Space Center, Fla. Prior to Orion’s launch from nearby Cape Canaveral Air Force Station, the Orion production team at Kennedy will install the capsule’s thermal protection systems, avionics and other subsystems. NASA says the 2014 test launch will send Orion farther into space than any human spacecraft in more than 40 years. After orbiting the Earth twice, Orion will plunge back toward Earth at speeds close to those it would reach during a return from the Moon.

NASA will use the resulting flight data to evaluate the performance of key Orion systems, including the craft’s heat shield and descent systems.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.