What makes an ideal trainer? Flying the Leonardo TH-119

I remember my first helicopter flight. My instructor gave me control in the hover, and the cockpit was soon a flurry of elbows and knees as I struggled to remain within roughly a cubic mile of sky. Characteristically unstable, learning to hover the CH-139 JetRanger, in which I received my Royal Canadian Air Force (RCAF) pilot wings, was like learning to swim by being thrown into the deep end of the pool. But, alas, that was a long time ago; technology changes everything.

Leonardo TH-119
The TH-119, based on the AW119, is Leonardo’s bid to replace the U.S. Navy’s aging TH-57 training fleet. Leonardo Photo
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My recollections of helicopter training came to mind as I arrived at Leonardo Helicopters’ modern facilities in Philadelphia, Pennsylvania. Under the Advanced Helicopter Training System (AHTS) program, the U.S. Navy has invited bids for a new military training helicopter to replace its aged and threadbare Bell TH-57B/C Sea Ranger helicopters; my mission was to help ferry Leonardo’s contender, the TH-119, to the Naval Helicopter Association fly-in in Pensacola, Florida.

What attributes make an ideal trainer? A training helicopter? A military training helicopter? I would have ample opportunity to muse over these questions during my upcoming two days of familiarization with the TH-119, and as a good trainer, it would teach me a few things along the way.

Meet the TH-119

I met Leonardo pilot and former-U.S. Navy flight instructor Doug Edge outside at the helicopter as a tepid dawn began to warm the horizon. He would be pilot-in-command and my adult supervision as I familiarized myself with the new machine. To be honest, I really didn’t know what role I was to fulfill during our roughly seven-hour ferry flight to Florida — beyond occupying space in the cockpit.

TH-119 Departure Weather
The weather appeared unsuitable for helicopter flying on the day of the TH-119’s scheduled departure from Philadelphia. Image courtesy of Rob Erdos

But pilots make bad passengers. Not thinking that he would endorse my cunning master plan, I ventured to Edge that a good trainer shouldn’t present any obstacles to an experienced pilot, so perhaps the best way to assess it was to climb onboard and see if I could start it and fly it to Florida. He shrugged his assent, pointed at the checklist on the right seat, and wandered away to take care of some last-minute paperwork. I had never before sat in a TH-119.

Besides, I still didn’t think we were going anywhere that day. The skies southwest of Philadelphia were ominously dark, and the forecasts dire. The remnants of a tropical storm were rolling up the Atlantic coast, leaving large portions of our route under low ceilings and precipitation. In my experience, it was the sort of day when helicopter pilots clean the garage.

Edge was undaunted. The TH-119 had just received its FAA instrument flight approval — the first certification of a single-engine helicopter under the current standards for instrument flight rules (IFR), according to Leonardo. Edge thought the conditions ideal to demonstrate the TH-119’s capabilities.

Leonardo’s contender for the U.S. Navy’s new helicopter trainer is the latest incarnation of the well-proven A109 helicopter lineage. Originally a twin-engine civil utility helicopter, the A109 has undergone decades of seasoning and tuning, as engineers optimized the design for a variety of missions.

The TH-119 is a conventional aluminum single-rotor helicopter on skid undercarriage. It features a Pratt & Whitney Canada PT6B-37A engine, with a takeoff power rating of 1,002 shaft horsepower. Its maximum gross weight is 6,283 pounds (2,850 kilograms).

The cockpit features the very capable Genesys Aerosystems integrated avionics suite. The panel is dominated by four 6- by 8-inch displays, which incorporate all of the latest aeronautical acronyms: instrument-certified dual GPS/WAAS navigation; a synthetic vision system with Highway-In-The-Sky (HITS) imagery; helicopter terrain avoidance warning system (HTAWS) with terrain and obstacle database; moving map, and integrated communication and navigation systems.

A trainer should be simple

My first impressions of the cockpit were positive. Ingress was comfortable, and with fore-aft adjustable seats and pedals, everything fell easily to hand. Controls featured a conventional collective-mounted twist-grip throttle — a critical mechanism that I thought particularly robust and well-designed. It will even feature an air conditioner, although our example was not so equipped.

Leonardo TH-119 cockpit
The TH-119 cockpit features advanced avionics by Genesys Aerosystems. The author found the TH-119’s cockpit to be tidy, functional and comfortable. Leonardo Photo

Engine start-up was typical for a PT6 installation: press the “start” button, crack the throttle at 12 percent Ng, and monitor. The start can be a bit warm if the helicopter had run recently, so attention is warranted. Starter cut-out is automatic, although there is no over-temperature protection during start, which should serve to keep students alert.

Pre-flight checks were quick and painless, consisting of testing the warning lights and tones, the fuel transfer pumps, hydraulic system and the electronic engine control’s (EEC’s) manual mode.

The Genesys displays were bright and flexibly reconfigurable to suit pilot preference. I’m frankly not a big fan of the Genesys avionics interface, however. Eschewing keyboard data entry for hot keys and knobs, the interface was often very keystroke-intensive. By way of example, pre-selecting the altitude on most aircraft requires twisting a dedicated knob. On the Genesys system however, that same action demands pressing the “menu” button, followed by “BUGS,” then “MINS,” then specifying which minimum altitude by pressing “MIN ALT,” and then twisting the value into the scratchpad using the knob. It could be easier.

In many display modes, the critical engine torque and rotor speed indications are small enough to hide behind my baby finger. The caution and warning system (EICAS) is a bit too talkative, offering frequent chirps, bongs and tones informing me of things that seemed of little significance. I don’t really care to be interrupted, for example, with news that the forward-looking terrain awareness feature of the HTAWS was inhibited in the vicinity of the airport (“FLTA INHIBIT” appeared on the primary flight display with an associated tone). In other cases, audio warning (such as altitude minima) were heard in one seat but not the other.

Despite the clunky interface, the TH-119 cockpit was awash in information, and the system worked perfectly during the course of multiple legs. Besides, whatever quirks the Genesys avionics may feature, keen young student pilots will master them, developing new skills in the process. The real test of its merits comes from the similarity of those skills to those required to operate military avionics in their future operational helicopters. Only the Navy can say.

About 30 minutes out of Philadelphia, the clouds threatened to envelop us, so we picked up an instrument clearance. The autopilot did a fine job in the transition and handling of an instrument landing (ILS Runway 21) to Clarksburg, West Virginia, and later on a GPS approach (RNAV 23 Right) in Knoxville, Tennessee. The TH-119 left me in no doubt of its merits as an instrument trainer.

In terms of performance, the TH-119 had a lot to offer, with an 1,800-foot-per-minute published sea level rate of climb and a hover in-ground-effect of 11,000 feet (3,350 meters, standard conditions, maximum gross weight).

TH-119 IFR Flight
The flight to Pensacola offered plenty of opportunities to trial the TH-119’s newly certified IFR capabilities. Rob Erdos Photo

En route in cloud at 6,000 feet (1,828 meters, air temperature 11 C/51 F), I pulled collective to 75 percent, cruising at 130 KIAS, which seemed like a reasonable cruise power setting, delivering a respectable 143 knots true airspeed. The flight manual reported a fuel flow of approximately 400 pounds per hour fuel flow. With 1,516 lb. (687 kg) usable fuel, Leonardo quotes a maximum (no reserve) range of 515 nautical miles. I found the ride quality quite reasonable. Edge explained that speed and range are a benefit to a trainer, as they afford efficient instrument training without undue wasted transit time.

As evidenced by the appearance of U.S. Navy Raytheon T-6 Harvard II trainers churning up the Florida sky, the military tends to favor high-performance trainers. In that regard, the TH-119 fits the bill nicely.

A trainer should be challenging

On the day after our arrival in Pensacola, I got another chance to fly the TH-119, this time with Leonardo instructor-pilot Scott Walden. We treated the flight like a Navy student training mission, with Walden demonstrating a series of standard maneuvers, and critiquing my attempts to replicate them.

We performed instructional traffic pattern work at Pensacola International Airport, including maximum performance take-offs and steep approaches. We simulated stuck-pedal procedures and a hydraulic malfunction. Walden demonstrated a touchdown autorotation.

Rob Erdos TH-119
The author cruises the TH-119 over a solid cloud deck en route to Pensacola, Florida. Photo courtesy of Rob Erdos

Throughout the series of maneuvers, I kept thinking, “There’s nothing unusual about that.”  The TH-119 seemed well-mannered and entirely conventional. Walden demonstrated his approach style, hastened slightly to reduce the sharp vibration peak during translational lift. In keeping with my personal definition of a good trainer, it was easy to fly, but with enough power and performance to make it challenging to fly precisely. I found the undercarriage — which features an internal suspension damper on the aft crosstubes — to be among the most pleasant and forgiving skids that I have flown.

By selectively disabling the automatic flight control system (AFCS), the TH-119 can be as difficult to fly as one wishes. There was much discussion about how the Navy would configure the AFCS for training.  It consists of dual stability augmentation systems (SAS) to enhance damping, with a selectable attitude-command control loop, which provides attitude retention stability to the helicopter, extensively reducing control activity. Recalling my prior experience training in the unaugmented Bell JetRanger, I couldn’t help but wonder whether hovering the TH-119 in attitude mode wasn’t too easy. Alternatively, the Navy may elect to challenge students’ fundamental “stick handling” skills in either SAS mode or with the AFCS off entirely. Such flexibility will prove invaluable.

It may arise from the relatively low pedal gearing, but I found the TH-119 a rather pedal-intensive machine, needing large and conscious coordinating footwork; on balance, a merit for a trainer as it will teach the lower half of each student how to fly.

It has a few oddities, to be sure. The cyclic force gradient is too high, requiring nearly constant use of the force trim release button during maneuvers to avoid overtorquing one’s right arm.  Similarly, even with minimum friction selected, the high collective breakout forces made small, smooth inputs a trick.

Its torque response to collective inputs is slightly underdamped, with a characteristic small overshoot of a two- to three-percent indicated torque whenever collective is increased. It required a bit of additional attention, although I suspect that this last “bug” is more “feature,” in that it will teach students to be mindful of power.

A third voice on the intercom reminded me of a further training capability that the TH-119 offers. I had almost forgotten that Edge was riding along in the cabin-mounted forward-facing observer’s seat. The wide-open cabin interior affords an unobstructed view of the displays and controls, and from his perch, Edge could ostensibly learn from my instructional mistakes before taking his turn at the controls.

Whither the new trainer?

The contenders have been courting the Navy for years. Lined up on the ramp at Pensacola for the delectation of the Navy brass were the Leonardo TH-119, a Bell 407 and Bell 427, and an Airbus H135. Such a collection induces speculation about the ideal attributes of a modern training helicopter. The U.S. Navy is apparently asking similar questions, as the contenders feature a diverse field including both single- and twin-engine designs. Leonardo is confident that it has the solution to the Navy’s training needs, and it’s the TH-119.

Editor’s note: Prior to receiving the opportunity to fly the TH-119 helicopter, the author was invited to Vergiate, Italy, to evaluate Leonardo’s twin-engine Trekker helicopter — which the company is also marketing as a capable multi-engine military trainer. Read about the author’s experience flying the Trekker here.

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