The Sierra Nevada Corporation (SNC) has shared new insights with TWZ into its proposal to replace the U.S. Navy’s T-45 Goshawk jet trainers. The company announced yesterday that it was putting forward its twin-engine Freedom jet, the only clean-sheet design currently known to be in the running, to meet the Navy’s future Undergraduate Jet Training System (UJTS) needs.

Our Jamie Hunter had a chance to talk in depth about the Freedom jet with Ray “Fitz” Fitzgerald, Senior Vice President of Strategy and Technology at SNC, and Derek Hess, Vice President of Strategy at SNC, at the Tailhook Association’s main annual symposium, which kicked off yesterday.

As part of its rollout yesterday, SNC had already highlighted the Freedom jet’s 16,000-hour airframe life and ability to perform 35,000 touch-and-goes and/or Field Carrier Landing Practice (FCLP) landings in that time, which we will come back to later on. The company also says Freedom has a 40-percent lower lifecycle cost than the existing T-45, as well as the ability to fly 30- to 40-percent longer sorties. In terms of performance, SNC says the jet is “representative” of 4th and 5th generation types, being able to pull down to -3 and up to +8 Gs, and reach an angle of attack up to 27 degrees.

“The advantages that we’re bringing to the table is that it’s a clean sheet design, which means that we are tailoring this exactly to the Navy’s needs. So, we talk about, train like you fight, zero compromises,” Fitzgerald said. “Every aircraft in the world has its compromises, but the Navy is special.”

“So, the three things that we’re trying to get across as a value proposition for the Navy, number one is over the entire life cycle of the of the aircraft, the entire life of the aircraft, is a significant cost savings,” he explained. “This plane was designed around two engines. These two engines have 20 million hours of flight time on them, well sustained out there in the world.”

The Freedom jet is designed around a pair of Williams FJ44-4M turbofan engines. FJ44 variants are in widespread use globally, especially on business jets, such as members of the popular Cessna Citation family. Having two engines also offers an additional margin of safety over single-engine types. The Navy’s existing T-45 jet trainer is notably a single-engine aircraft.

The “number two value proposition is that we are the only competitor right now, and this is very important, that can do field carrier landing practice, FCLP-to-touchdown,” he added. “Very important for the Navy. You have to train like you fight. And every time you land on an aircraft carrier, you’re flying it into the deck. You’re not flaring or pulling throttles back. FCLP-to-touchdown is critical.”

FCLP landings, which are part of the Navy’s current curriculum for training naval aviators, are conducted at bases on land, but are structured to mimic as closely as possible the experience of touching down on a real carrier. In March, the Navy publicly released new requirements for the UJTS effort, which axed the need for its future jet trainers to be capable of performing FCLP training. Years ago now, the service had already announced that it was eliminating the requirement for the jets to be able to actually land on or take off from carriers, as T-45s do now. If the Navy does not reverse course, these controversial changes are set to fundamentally alter how the service trains new naval aviators. They may not see a carrier until they reach the Fleet Replacement Squadron (FRS) in charge of the aircraft type they have been assigned to fly.

SNC’s Fitzgerald also took the time to point out here that the 16,000-hour airframe life SNC says the Freedom jet will offer is double the Navy’s current stated requirements for UJTS.

“The third point in the value [proposition] is the fact that when we designed this, and [if] we are selected by the Navy, we are handing the Navy the entire digital package for this aircraft,” he continued. “We want to have the ability to compete in the future for future changes, but the Navy will have the data. They can do upgrades, modifications, whatever. They’re going to own it [the data rights] on onset.”

Fitzgerald claimed that this is the first time in the history of U.S. defense contracting where an original equipment manufacturer (OEM) has offered this level of data rights, and described it as an “absolute game-changer.”

The core elements of SNC’s proposal are reflected in the basic design of the Freedom jet.

“I think it is a natural tendency to go, ‘how do you replace the T-45?’ That’s not the question we had ourselves,” Hess, the Vice President of Strategy at SNC, said. “We pride ourselves on delivering, solving tough problems for our customers, in this case, the U.S. Navy. So what we designed this aircraft around is better quality training for UJTS at a lower lifecycle cost than they’re currently paying.”

“The landing gear is a dead giveaway that this was always envisioned for the naval training mission,” he continued. For “FCLPs, using this trailing link landing gear is a huge design cycle.”

A trailing link or trailing arm landing gear is specifically designed to help smooth the impact of landing and/or operating from rougher fields.

One of “the other things that we did was put a cockpit in this that is a thoroughly modern cockpit that can display things like an F-35 or an F-18,” Hess continued. “And then we gave it an eight G capable platform and a 27 degree high AOA [angle of attack] maneuvering capability. And we did that because we just avoided the supersonic and transonic region.”

“If you try and do something that gets up into that transonic region, you compromise on what your wing is, and therefore you can’t get the performance,” he explained. “And so that’s why you need a giant engine that pushes you through the drag rise of what a normal, typical fighter wing is. This is a much higher aspect wing, and we get the G onset rate, the sustained turn rates, and maneuvers that you need to train young men and women to become naval fighter pilots.”

“So all of the modeling that we have done in the MBSE [model-based systems engineering] and fluid dynamics world has been borne out by our wind tunnel testing and all those kinds of things. And we’re always a degree or two conservative,” Hess also said. “For example, this is a 32-degree angle of attack capability that we tame down to 27 degrees to make sure that it has level one handling qualities. The other thing is, this aircraft, this wing, builds all the lift through conventional means. Where you have other aircraft that have large chines on them, and that is what you need when you get into the transonic region, because your wing can’t produce that lift, so you do vortex lift over those large chines, and that’s, frankly, where you end up with problems in handling qualities, is because you can’t control the shedding of the vortices and things of that nature.”

“And it becomes a watershed there, right? So when you start with the chines, that the drag coefficient on that becomes huge, which means you need a bigger motor to dig that out, which means higher fuel – you know, just boom, boom, boom. It just bespoke,” Fitzgerald also interjected. “We started with the motor, went with the wing, went with the training capability up front, and really thought this through.”

In addition to its core shaping, Freedom’s wing will feature leading-edge slats and flaperons, as well.

Hess and Fitzgerald were responding here to a specific question about the use of digital modeling in the Freedom’s design. While digital engineering has proven to be useful across the aerospace industry, there has been growing skepticism about the full extent of the benefits it offers in recent years. Boeing’s T-7A Redhawk jet trainer for the U.S. Air Force had been a notable poster child for digital engineering and design tools, but developmental troubles with that aircraft have added to a growing view that the technologies are not as revolutionary as many had hoped. A navalized version of the T-7 is also a contender to replace the Navy’s T-45s.

“I really think it is important to say you don’t need a fighter to learn how to fly a fighter,” Hess added. “You need something that gives you all the tools to practice everything you want to and then move the graduates who are more prepared to get into those gray jets after graduating in this airplane.”

“You can complete a lot more training in this jet at a much lower cost per hour,” Fitzgerald, the SNC Senior Vice President of Strategy and Technology, further noted. “And then as you step into the fleet, you’re not having to burn the very exquisite, expensive aircraft to do very mundane training tasks.”

It is important to reiterate here that SNC’s proposal, overall, stands in contrast with the Navy’s currently stated requirements, especially when it comes to the matter of FCLP capability. The requirements changes, which have notably come on the back of Navy investments in virtualized training and automated carrier landing capabilities like Magic Carpet, have significantly opened the field offerings based on existing land-based jet trainer designs. In addition to Boeing’s navalized T-7, Lockheed Martin and Korea Aerospace Industries (KAI) have been offering the TF-50N, while Textron and Leonardo are pitching what is now branded as the Beechcraft M-346N. Both of those aircraft are based on in-production designs with significant global user bases already.

“You want … your – I call it your lizard brain – to be trained to do the things you are going to do when things go south on you, because the way a [former Air Force pilot] like me lands an airplane is 180 degrees different than a carrier guy,” Hess said in talking about why SNC has made FCLP capability a focus of its proposal. “I touch down, go to idle. He touches down, slams down, goes to MIL [maximum non-afterburner thrust], and is ready to take off again.”

“This is why FCLPs are so important,” Fitzgerlad, a former naval aviator himself, added. “On that dark, stormy night, and everything’s just going bad, you rely on muscle memory, right? So when you think about muscle memory, as a carrier aviator, you’re on speed, so you’re on the right AOA, so the hook and the gear are the right AOA to trap, and everything hits at the same time. If I’m at a slow AOA, it means my nose is up, which means the hook grabs first and slams you down. You can break a jet like that. If I’m at a fast AOA, the nose is lower, hook is up, you skip across, and you go flying again, which is not good either.”

“So every single time we’re doing an FCLP, as soon as you fly into the deck, you crash into that deck, he [the Air Force pilot] goes idle, and [says] ‘I want a nice flare, soft thing.’ We [naval aviators] fly it into the deck, and as soon as we touch it, it’s full power, 180 out,” he continued. “So that muscle memory, I mean, it’s what will save lives.”

SNC’s Hess also argued that if the Navy’s future jet trainers do not allow for FCLP landings, it will put additional more onus on FRSs and operational units to do that training. That, in turn, could take time away from other priorities and increase wear and tear on the Navy’s fighter fleets.

In addition, while SNC is a firmly established name when it comes to the special mission aircraft conversion and modification business, especially for U.S. government customers, Freedom is its only foray to date into actually building an aircraft from scratch. The jet first emerged from a partnership with Turkish Aerospace Industries (TAI, and also abbreviated TUSAS in Turkish), but SNC has been working on it independently for some years now.

“The Navy hasn’t really put out hard requirements yet. We’re expecting a draft RFP [request for proposals] soon, this fall, with a hard RFP by winter. That’s the latest we’ve heard from the Navy,” Fitzgerald said. “I think they’re still trying to figure out what their hard requirements are, which is why we’re here, trying to say, ‘Hey, make sure the aperture is open enough so that we can compete,’ because that’s what we want to do. That’s all we’re asking for is a shot at the table.”

Altogether, the Navy’s forthcoming UJTS competition is shaping up to be hotly contested, as well as an important watershed moment for how the service trains new naval aviators going forward.

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