May 1, 2001

Cover Story: EC-130 B4: More Than a Tour Ship!

Contributing writer Ron Bower explains why the heli-tour label that some have slapped on the EC-130 B4 may be too narrow for this multifaceted helicopter.

by Ron Bower, Reporting from Grand Prairie, Texas

EUROCOPTER DROPPED THE curtains at Heli-Expo 2001 in February, revealing a beautifully painted EC-130 B4, the latest member of its civil helicopter family. The helicopter was in full livery, ready to join launch customer Blue Hawaiian’s large air tour fleet operating out of Maui.

The initial press coverage and HAI floor "scuttlebutt" seemed to label the EC-130 as a widebody AS-350 B3 "tour operator’s ship." This label is understandable, since the AS-350 family has become the de facto industry standard for many tour operators, particularly in Hawaii.

However, after flying the EC-130 B4, I found this "tour-ship" tag to be far too narrow a description for what should be a market-pleasing helicopter in a wide variety of customer missions. These could include: electronic newsgathering (ENG), emergency medical services (EMS), offshore, police, and executive transport.

In early March, I had the opportunity to fly 2.3 hours in the EC-130 at American Eurocopter’s facility in Grand Prairie, Texas. The EC-130 was more than I expected—much more.

Flying the EC-130

The Texas CAVU day with a light southerly wind was perfect for my EC-130 flight. My host was Didier Delsalle, a Eurocopter staff test pilot based at the company’s main production factory in Marignane, France.

Didier (pronounced slowly in Texas as "D-D-A") has been with the EC-130 since its inception. He was the first person to fly the helicopter. He is a former French military jet and helicopter pilot, and, like most experimental test pilots I’ve met, is a consummate professional. He knows, through hands-on experience, the fine details of how and why the helicopter flies the way it does.

We first conducted a classroom systems and performance review, and then went to the flight line, where we opened all the cowlings and did a lengthy walk-around preflight inspection and briefing.

The EC-130 (F-WQES) initially was a production test aircraft, but is now painted with the factory’s attractive multicolored design. All EC-130s will come from the factory equipped as this ship was, with many features included in the base price—just over $1.6 million.

Among the standard equipment items usually listed as options: rotor brake; left rear sliding door; seven-seat standard interior; flight instruments; avionics master switch; KX-165 nav/comm; Garmin 430 GPS nav/comm; ELT; KT-76C transponder with encoder; KI-525 HIS; and an NAT AA95/AA 38 eight-place intercom.

Next, we strapped in and fired up. With a simple flick of a switch, the 847-shaft-horsepower Turbomeca Arriel 2B1 engine came to life. We had a full tank of 143 gallons (972 pounds) of fuel on board.

We began with hovering maneuvers, both in and out of ground effect. I perceived no difference between flying a helicopter equipped with a fenestron tail rotor system and flying one with a conventional tail rotor. More than ample tail rotor authority was available. The engine was loping, with untapped power to spare.

For the next phase of our flight, we departed south to open country for the flight maneuvers. The ride was typically smooth, very similar to that of its AS-350 cousin. We quickly accelerated to an indicated airspeed of 130 knots.

After a few steep turns, quick stops and hovers out of ground effect (HOGE) at 2,000 feet MSL, we picked out a confined area for approaches and landings. The extra-large windshields and chin bubbles afford the pilot excellent views of obstacles and the immediate landing area. The pilot can see even the rotor head through the larger overhead windows, and has much-improved forward visibility for landing and confined-area approaches.

We then validated the altitude loss of the height-velocity curve from a zero-airspeed HOGE by chopping the throttle and entering an autorotation. All of these maneuvers were docile and similar to the newer AS-350 series with the improved AS-355 rotor blades.

From several flight attitudes, Didier asked me to remove my hand from the cyclic to demonstrate the EC-130’s flight stability. There was no forced trim, stabilization, or autopilot, yet the aircraft held the attitude.

We then returned to the airport to shoot a few autorotations. These were gentle with a vertical rate of descent in the 1,700 feet per minute to 1,800 fpm range. The flare was smooth, with just a little forward cyclic required for a flawless touchdown.

Once we completed the autorotations, our photo chase aircraft—an AS-350 B2 flown by American Eurocopter’s Bob Reuland—joined us in the practice area.

Didier showed me some of the controllability maneuvers used in the test flight program and for certification. These maneuvers should carry a "don’t try this at home" warning label.

We climbed considerably higher than the photo ship and gave them a readying countdown for entry. Didier made an aggressive forward-pitch nose over from an OGE hover. It must have been Didier’s jet-fighter background, because the entire windshield suddenly became earth-colored and started getting bigger, fast. It looked like a 90° vertical angle, though I am sure it was probably "only" 70° or 75° from the horizon. I have never seen anything quite like that.

Didier next began a steep cyclic climb that seemed to stand us on our tail. When we were almost hanging, he followed with an abrupt left pedal pressure that caused us to swap ends quickly. In what might be called a helicopter version of a wingover, he gave me one more good full view of the earth through the overhead windows. I started to say, "Well, Didier, is that all this baby will do?" but when I opened my mouth, no audible sound came out.

A melded heritage

The EC-130 B4 is most closely related and shares the same FAA Type Certificate with the popular AS-350 AStar. There are about 1,700 commercially registered single-engine AS-350s registered worldwide, plus a goodly number more in military roles (designated the AS-550 Fennec). The EC-130 B4 received its FAA certification in late December 2000.

The engine, drive train, main rotor system, fuel system, and hefty tailboom are straight from the super-powerful AS-350 B3, one of the industry’s top "high and hot" performers. With more than two decades of engine, transmission and rotor system enhancements in the AS-350 series, Eurocopter made these mature AS-350 B3 systems the working core of the new EC-130.

In addition, the EC-130 incorporates beneficial vestiges of other popular Eurocopter products. For example, the shrouded fenestron tail rotor system is derived from the EC-135, the dual hydraulics from the AS-355 N, and the cabin structure is spawned from the EC-120.

The EC-130 is a stretched version of the AS-350 fuselage—but stretched in a different way. Rather than stretching the helicopter longitudinally with a cabin plug, the company stretched it laterally by turning it into a "widebody." This is a far easier approach if you have a predecessor with extra power, rotor performance and a strong transmission, like the AS-350 B3.

None of these components required expensive redesign or manufacturing changes to work in the EC-130. As a result, the EC-130 didn’t take the quantum price jump that we usually see with redesigns.

A roomier cabin

The EC-130 cabin section might be described as an EC-120 cabin stretched laterally with a center plug. If you look at the helicopter from the nose, you can see the extra 20+ inches of the middle windshield segment, which matches the added width from the lateral plug.

The cabin sides, large outboard windshields, large chin bubbles, and doors are right off the EC-120—an off-the-shelf approach that helps hold down development and manufacturing costs. The EC-130’s cabin length is a foot longer than an AS-350’s. That means a 24% increase in cabin volume, from 105 cubic feet to 130 cubic feet.

This wider cabin allows Eurocopter to add up to two more seats than the standard six-seat (2+4) configuration of earlier AS-350 cabins. The EC-130 has a comfortable seven-seat (3+4) version and an eight-seat (4+4) version. The latter cabin configuration will be available later this year.

Access to the spacious cabin is easy through large jettisonable crew or aft doors. A sliding aft door on the left side comes standard. On the skids, entry steps (also standard) run the length of the doors, providing easy access to the cabin.

The EC-130’s wider and longer cabin area means that more room is now available for cargo, or in EMS roles, for litters and medical crew. I expect the EC-130 soon to begin penetrating the space-conscious medical market—more so if and when the helicopter receives single-pilot IFR (SPIFR) certification.

The aft fuselage is still based on the AS-350, but the two side baggage compartments got a needed 22% increase in volume—a benefit from the flared fuselage that starts just forward of the aftmost baggage compartment.

Changes in performance

The many benefits of the EC-130’s widebody cabin resulted in only minor performance differences due to changes in airflow around the cabin. On the aft tailboom area, the fixed horizontal stabilizer fins, which are taken directly from the AS-350, had to be lengthened a couple of inches on each side to keep pitch stability in check.

In addition, as on the EC-120, what look like fairings on the aft skid cross-tubes are really shaped composite airfoils called "profilers." These were installed primarily to enhance yaw stability in flight. The profilers might be compared to additional vertical fins, or endplates, which often are found on the tips of the horizontal stabilizers on many helicopters.

Because the EC-130 is so closely related to the AS-350 B3 due to a common powerplant, rotor system and drive train, a comparison of the two serves as a satisfactory indicator of the overall effect of these airframe changes.

Since we are talking about comparative performance, it is important to remember that the EC-130’s maximum gross takeoff weight (MGTOW) is 5,291 pounds—331 pounds heavier than the muscular AS-350 B3.

Standard-equipped EC-130s have a published useful load of 2,293 pounds. Loading seven seats and calculating the weight using the FAA’s average of 170 pounds, you get 1,190 pounds for the pilot and passengers. If you fill the tank with max fuel, add another 972 pounds. If you then take the 2,293-pound useful load and subtract the weight of seven people minus full fuel, you get 131 pounds still unused.

In other words, you can fill all seven seats, top off the tank and still not be at max gross takeoff weight. Now there’s a novel idea that might sell!

However, the EC-130’s wider and flatter nose carries with it a minor drag penalty, which translates into a slower cruising speed. The helicopter cruises at 131 knots, about nine knots slower than its -B3 cousin at a comparable MGTOW of 4,960 pounds. Since fuel capacity and burn rates are the same in both helicopters, the EC-130’s maximum range decreases by 6% compared with the -B3.

Using Eurocopter’s published technical data books, I found that, at the AS-350 B3’s 4,960-pound MGTOW, other minor performance differences are apparent. There is a 6% reduction in the -B3’s ear-popping climb rate of 2,037 fpm and a 2,000-foot penalty in maximum hovering altitudes—both in and out of ground effect.

The EC-130 is still an impressive "high and hot" performer, however. At 4,960 pounds, the EC-130’s service ceiling is 17,700 feet MSL—1,200 feet higher than the -B3.

While I don’t consider the EC-130 a utility work ship, it has a respectable approved cargo swing load capacity of 2,557 pounds (same as the AS-350 B2). With the pilot-in-command (PIC) already approved for the far-left crew seat, sling work will be an added benefit to some multi-use operators.

The fenestron

One difference between the EC-130 and the AS-350 that is immediately apparent is the anti-torque system. This is not a radical application of the technology. For decades, Eurocopter has used the fenestron on a variety of helicopters—the Gazelle, Dauphin, EC-120, EC-135, and EC-155.

There are three important benefits in using the fenestron. The first is safety. On the ground, the shroud surrounding the tail rotors prevents passengers and ground crew from inadvertently walking into the invisible rotor blades.

Last year, 38 tail rotor accidents were reported in the United States. The fenestron can significantly relieve this "pilot’s worst nightmare."

The second benefit is a lower noise level. Rather than having two paddle-like blades thrashing the air, the EC-130’s enclosed tail rotor has 10 much smaller blades that are asymmetrically spaced to reduce noise-generating harmonics.

In addition, under the control of the full-authority digital electronic controls (FADEC), the EC-130 automatically reduces main rotor RPM in cruise by about 3.5%, from 400 RPM to 387 RPM. The yield is lower decibel readings, and a much quieter noise signature than the AS-350 series.

After my flight, but before shutdown, I asked Didier to perform a fly-by directly overhead at 400 feet AGL. The EC-130’s published Effective Perceived Noise Level (EPNL) rating is 84.3 EPNdB. This rating deals with perceived noise, and my perception is that the EC-130 is indeed a quiet helicopter, even at that altitude.

The third benefit of the fenestron is efficiency. Think about it: On most conventional tails, the optimum tail rotor airflow usually is blocked by the tailboom and the vertical fin. To get the required anti-torque thrust, you have to force more air around the blocking tailboom and fin. This usually requires moving the air with bigger and louder tail rotor blades, often using up to 25% of engine horsepower. A more efficient tail rotor could free up engine horsepower for application where it counts—to the main rotor.

To enhance the fenestron’s efficiency, the output thrust of the EC-130’s rotating tail rotor blades flows across 10 fixed "stator vanes," which are carefully shaped airfoils that smooth and optimally direct the airflow. The end result in the EC-130 is a safer, quieter and more efficient tail rotor system than conventional tails.

On AS-350s, the tail rotor control must be hydraulically assisted, or "boosted." This is not the case with the EC-130. Hydraulic boosting has been eliminated, along with the extra weight and cost associated with it. This is allowed because the tail rotor authority of the EC-130’s fenestron is very high and is applied with minimal pedal pressures. In OGE hovers, whether the helicopter was downwind or flying sideways (at a GPS-indicated ground speed of 52 knots), I had no trouble maintaining tail control during our flight.

Once the helicopter reaches a forward airspeed of about 60 knots, the large tail fin takes over and almost no pedal inputs are needed. This means that, in the unlikely event of a tail rotor failure during cruise flight, you probably could continue to fly to a safe landing area.

Dual hydraulics: The road to SPIFR

A major change in the EC-130 from the AS-350 series is the incorporation of a dual hydraulic system, rather than a single set of pumps, servos and control actuators. This proven dual hydraulic design is borrowed from the AS-355 N Twin Star.

Although hydraulic failures are rare in helicopters, a "lost hydraulics" emergency can be a challenge for pilots and has caused numerous accidents (many of them in training for that emergency). Most single-engine helicopters have only one hydraulic system for flight controls.

On the EC-130, if you lose a set of hydraulics, the redundant system makes the loss of the system almost a non-event. Another benefit of the dual hydraulic system is the elimination of the accumulator, an emergency hydraulic pressure storage tank found on the single hydraulic systems in the AS-350 series.

Dual hydraulics are now generally accepted as a requirement for SPIFR certification, due to the high pilot workloads that result when the pilot has a failure in a single-hydraulic system while in the soup. Attempting to retrofit and certify dual hydraulics on a single hydraulic aircraft is extremely difficult and has brought several aftermarket shops to their knees.

The EC-130 is presently certified only for VFR flight, but I suspect SPIFR certification is in the cards. While there is presently no certified autopilot for the EC-130, Eurocopter already has installed autopilot annunciators in the instrument panel. This decision by the OEM seems to be a telltale sign of a move toward SPIFR certification. SFIM’s autopilot used on the AS-350 and AS-355 is a likely candidate. Given the EC-130’s inherent flight stability, it should be an excellent IFR platform.

A smarter, two-channel FADEC

Nearly all the new aircraft hitting the market now have full-authority digital electronic controls (FADEC). In the FADEC-equipped EC-130, starting the engine is as simple as you can get: set the throttle to the ground position and hit the start switch. The FADEC makes an optimized, temperature-stabilized start.

These computer units control the engine’s fuel supply with electronic speed from light-off to shutdown. By rapidly monitoring a wide range of engine parameters, especially turbine outlet temperature (TOT), they can eliminate expensive hot starts, warn you of reaching power limits, record any exceedances, and provide accurate time logging.

With FADECs now gathering so much data from a variety of sources, they need someplace to convert the data and display it as meaningful information. Eurocopter calls its glass panel display the Vehicle and Engine Multifunction Display (VEMD).

I found the VEMD easy to read and easy to interpret in flight. It provides a changing first limitation indication display to show which limitation you are closest to reaching. It even warns you audibly if you are close to exceeding an operating limit. At the end of the flight, the VEMD allows the operator access to maintenance and flight log information by paging through its various screens.

In the EC-130, the FADEC is dual-channel, offering a redundant path and processing if the unit encounters a problem. This next-generation, dual-channel FADEC reduces the likelihood of a crippling in-flight emergency and makes the EC-130 one of the smartest single-engine helicopters in the sky.

A simple back-up mode with minimal pilot intervention is easily activated for training or in case both FADEC channels fail. I also believe two channels will prove to be another benefit in the aforementioned and likely SPIFR certification.

In the end, whether an operator selects the EC-130 B4 depends on how closely the -B4 matches the company’s needs. Another consideration is how well the manufacturer understands those needs and is able to enter into a mutually profitable partnership with the customer. Rudy Palladina, American Eurocopter’s new CEO and a former operator in Canada, probably said it best: "The operator has to get the right product, and the manufacturer has to get the product right."

My time with the new EC-130 convinced me that Eurocopter has the right product for many operators, and that it has indeed "got the product right."

Ron Bower is a contributing editor at Rotor & Wing. He has 8,000 hours total time in helicopters and fixed-wing aircraft. He also holds the around-the-world helicopter speed records for both easterly and westerly directions. Readers may reach him by e-mail at ron@bowerhelicopter.com.