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T-X Advanced Trainer Replacement - 2015 Requirements

Air Force officials released requirements for the T-X trainer aircraft family of systems that will replace the T-38 Talon, 20 March 2015. The release was the first under the service's new 'Bending the Cost Curve' initiative and follows Secretary of the Air Force Deborah Lee James' emphasis on increased dialogue with industry to build affordability into the acquisition process. "The industry dialogue will help guide Air Force evaluation of threshold and objective requirements, producing better informed cost-capability decisions," James said. "The T-X requirements are being released approximately 10 months earlier than under the normal acquisition process and is part of an ongoing effort for more deliberate and open engagement with industry," said Brig. Gen. Dawn Dunlop, the director of plans, programs and requirements at Air Education and Training Command.

As Lockheed Martin talked up the clean-sheet option, and Air Force requirements were clarified, Northrop Grumman concluded it had little choice but to ditch the Hawk bid in favor of another brand-new design. The only remaining off-the-shelf platform was the T-100, a collaboration between General Dynamics and Italy's Alenia Aermacchi based on the latter’s M-346 design. However, in early April 2015 General Dynamics pulled out of T—X. The firm‘s decision to ditch its T-X effort as a prime contractor was announced on 26 March 2015, just a week after the Air Force released its final program requirements.

According to a July 2015 statement from the USAF's Air Education and Training Command, the service wanted an aircraft capable of 7.5g turns “while losing no more than 2,000ft of vertical altitude and 10% of the initial airspeed”. The sustained G maneuver would be flown with a standard configuration (i.e., clean with no external stores), at or above 80% fuel weight (relative to maximum fuel capacity), steady state flight, and standard day conditions. The maneuver will begin in level flight (flight path angle no lower than zero and no higher than two degrees nose high), wings level (+/- 5 degrees of bank), at or above 15,000 feet pressure altitude, and at or below 0.9M. From this point, the pilot shall immediately initiate bank and back pressure to achieve the sustained G. The sustained G must be maintained for a minimum of 140 continuous degrees. The pilot may begin reducing the load factor and rolling out after a minimum of 140 degrees in order to roll out at approximately 180 degrees of turn.

The flight path angle shall be no lower than 15 degrees nose low and the aircraft shall descend to no lower than 13,000 feet pressure altitude during any portion of the entire 180-degree maneuver. There is no power setting specified for this maneuver. The aircraft may lose no more than 10% of the initial airspeed during the 180-degree maneuver. There are no specified degrees of turn for roll in or roll out. “Approximately 180 degrees of turn” is meant to describe a recognizable maneuver without mandating exactly 180 degrees. There is no specified length of time for the 140-degree portion of the maneuver or for the 180-degree maneuver as a whole.

Minimum acceptable load factor will be 6.5 sustained for a minimum of 140 degrees. The lowest load factor registered during the 140-degree period will establish sustained G for the maneuver. For example, if the aircraft maintains 7.2Gs for less than 140 degrees and then drops to 6.9Gs by the end of the 140-degree period, 6.9Gs will be used as the maximum sustained G. There is no requirement to exceed 7.5Gs.

The Weapons Systems Support Pod (WSSP) is intended to be an electronic-type pod compatible with MIL-STD-1760 interface capability. The ALQ-188 carried by the T-38B (adversary for F-22 training) is a good example of a WSSP. Note that there is no requirement to integrate a specific WSSP. The requirement is only to have carriage capability to allow for potential future integration. Carriage requirements will be further defined in the System Spec. The T-X requirements identified three key performance characteristics for the advanced pilot training mission: sustained G, simulator visual acuity and performance, and aircraft sustainment. While there are just over 100 requirements in all, these were the most critical to ensure the T-X Family of Systems closes training gaps and creates strategic agility for the future. A highlight in the requirements is embedded training with synthetic sensors and data link. Significant progress has been made the past decade in synthetic training that very closely approximates the real system. Currently, nine partner air forces already have advanced pilot training systems that take advantage of these increased capabilities.

Prior to the new change to evaluate clean sheet designs against non-development items the USAF stated that they believed a "fly-off" was not necessary due to the familiarity they acquired during the Analysis of Alternatives in 2010 and in 2014. The government will not have a fly-off, but is looking at having a demo of some sort. If a flight demo is part of the source selection, the contractors need to be airborne and have relevant flight-test data as proof. The government had not developed the evaluation criteria or begun drafting source selection plan.

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Page last modified: 31-01-2017 16:07:33 ZULU