Language in the recently approved Senate Armed Services Committee markup of the fiscal 2015 defense spending bill is giving new hope to nascent business jet manufacturer Eclipse Aerospace in its bid to replace the Air Force’s Raytheon T-1A Jayhawk trainer with new or leased Eclipse 550s very light jets.

The T-1A is a militarized version of the Beechjet 400A, with thicker wing leading edges and windscreens, along with a jump seat and avionics rack in the cabin.

The language, which was not included in the House’s version of the same bill, directs the secretary of the Air Force to "report on the options for replacing or upgrading the T-1A trainer aircraft’s capability."

That would require the Air Force to take another look at its latest plans to spend $313 million on an avionics upgrade for the existing T-1A fleet, considering options for leasing or buying different aircraft for the mission.

Eclipse responded to two earlier Air Force requests for information from industry, in 2006 and 2012, for options on replacing the T-1A with a very light jet. The company, which is now producing 1.5 new $2.9 million Eclipse 550s per month at its Albuquerque, N.M. plant, could ramp up to 10 aircraft per month, Eclipse President Mason Holland says. He added that leasing portions of the existing fleet of 270 aircraft may also be an option. Eclipse estimates the Air Force could save about $11 billion over 20 years in operations and sustainment costs with an Eclipse 550 fleet, in part due to significantly lower fuel burn, in aircraft that already have NextGen-compliant integrated avionics and autothrottles.

The T-1A avionics upgrade is meant to address obsolescence issues with the aircraft’s traffic collision awareness system (TCAS), flux detectors (part of the navigation system), maintenance diagnostic computers and multi-function displays. The T-1A will also need GPS and automatic dependent surveillance broadcast (ADS-B) out avionics to meet the FAA’s NextGen surveillance mandate by 2020. The airframes are expected to last until 2032, when a service life extension would be needed, barring a fleet replacement.

The Air Force puts about 700 undergraduate pilots for airlift and tanker roles (C-17, KC-135, KC-10 and C-130) through specialized undergraduate pilot training (SUPT) for advanced training using a fleet of 178 T-1As. Twenty-one of the aircraft are fitted with extra electronics for Combat Systems Officer training. Fighter and bomber undergraduates use the T-38C for SUPT before moving on to the F-15, F-16, A-10, F-22, F-35, B-1 and B-52. Helicopter pilots who will fly the CV-22 or the H-60 have a separate advanced track, although all undergraduates, fixed-wing or rotary-wing, use the T-6A for primary training .

With the T-38C set for retirement between 2023 and 2029, to be replaced by the T-X trainer, the Air Force is mulling changes to its basic training structure. Included are options for SUPT with the T-1A and T-X, a composite track with 52 hr. of simulator time for T-1A pilots, or a generalized track using the T-X for all advanced training for fixed-wing pilots.

Regardless of that decision, the looming T-1A upgrades remain a problem.

The Senate Armed Services Committee says it is concerned that the T-1A, although it came into service after the T-38C, has not received "similar upgrades and service life extensions," in part due to budget constraints caused by the T-X program. The bill calls for the Air Force to submit a report to Congress on "the options for replacing or upgrading the T-1A aircraft’s capability, to include options of leased aircraft or services, not later than 90 days after the date of the enactment of this Act."