Hands On: AIN Flies with the Genesys HeliSAS

 - April 16, 2018, 1:23 PM

“It was like déjà vu all over again,” as Yogi Berra might have described it.

Five years ago at Heli-Expo 2013 in Las Vegas, I flew a pristine, privately owned Bell 407 with a newly installed Cobham HeliSAS autopilot and stability augmentation system (SAS). Now I was again flying over the Nevada desert in another HeliSAS-equipped helicopter at HeliExpo 2018, also in Vegas. The main differences between these two flights are the company’s name and ownership, the helicopter and a few enhancements to HeliSAS itself.

In April 2014, Cobham sold S-Tec Corporation (the producer of HeliSAS and other autopilots) and Chelton Flight Systems to Genesys Aerosystems, a new company formed by Gordon Pratt and Rick Price (the original co-founders of Chelton) and former Cobham Avionics executives Roger Smith and Tammy Crawford. According to the Genesys Aerosystems website, “You may recognize us as the people who pioneered the world’s first FAA-certified 3D synthetic vision EFIS and GPS/WAAS navigator. Or you may fly one of the 40,000 autopilot systems we’ve shipped over the last 35 years.”

The helicopter that Chad Howard, Genesys field service engineer and test pilot, flew to Heli-Expo 2018 for demonstration flights is a former U.S. Army OH-58A+ Kiowa, a militarized version of the Bell 206, and therefore considered an experimental aircraft by the FAA. No longer olive drab, the shiny white N762MF sports a blue and black Genesys Aerosystem’s logo and looks very much like a garden-variety 206…until you notice “EXPERIMENTAL” painted on the lower section of the cockpit doors. When it wore olive drab, the helicopter carried a 7.62 mm M134 Minigun, Howard said, and its four seats still sport their original military-style harnesses. Genesys uses its OH-58A for flight-testing and customer demonstrations, he told AIN editor-in-chief Matt Thurber, me, and “Chuck” (a pseudonym for another pilot who preferred not to be identified in this report) during our safety briefing before our flight on March 1.

view from helicopter

SAS panel
SAS engages the system to provide attitude stabilization at all speeds. HDG selects the desired heading the pilot wants to fly. If a horizontal situation indicator (HSI) is installed, HeliSAS will yaw to and maintain the heading selected by the heading bug. If there is no HSI, the HDG function will maintain the existing GPS track. NAV selects the active GPS, VOR, or localizer course and automatically intercepts and tracks it. (VOR and localizer coupling require an HSI. GPS does not.) BC intercepts and flies a back course localizer approach (BC requires an HSI). ALT maintains the existing altitude for an indefinite period. VRT (vertical navigation) allows automatic flying of an ILS glide slope or GPS VNAV, if a WAAS-enabled GPS is installed. (Both functions require an HSI.) (Top photo: Matt Thurber, bottom: R. Randall Padfield)

This same month Genesys delivered its 1,000th HeliSAS to an EMS operator for an Airbus EC130T2. “Almost 25 percent of our 1,000 installations are in EMS helicopters in the United States,” Jamie Luster, Genesys director of sales and marketing, told me. “We’ve captured most of the EMS market here.” The obviously successful product, which weighs in at less than 15 pounds, “brings safety and workload-reduction advantages to a wide range of light and medium helicopter models,” she explained.

Although the company’s name and ownership have changed over the years, it has always been based in Mineral Wells, Texas. This small town of about 15,000 residents was once the home of the Army’s Fort Wolters, where thousands of Vietnam-era Army and a smaller number of Air Force helicopter pilots (including this writer) and non-U.S. military pilots became hover lovers in Bell 47s and Hughes TH-55A trainers. Fort Wolters itself was deactivated in 1973.

On before Takeoff/Off after Landing

HeliSAS is designed to be engaged at all times during flight—“SAS on before takeoff and SAS off after landing,” as Howard put it—but a pilot can easily override the system and even fly without it, although this defeats the purpose of having it. While hand flying is a good way to maintain “stick-and-rudder” skills, flying manually does get fatiguing on long legs and in turbulence; it can also become a safety factor in low visibility, especially when flying single-pilot. HeliSAS provides attitude stabilization and force feel, which improve handling and help the pilot avoid inadvertent cyclic control inputs that could result in dangerous attitudes. Roll trim limits are plus-5-degrees to minus-5-degrees and pitch trim limits are plus-11-degrees to minus-6-degrees. In whiteouts, brownouts, and other low-visibility situations, where a pilot may lose visual reference, HeliSAS is invaluable in maintaining a safe and stable attitude.

“HeliSAS has a wonderful feature that allows the pilot to recover from an unusual attitude,” Howard explained. “If HeliSAS is off and the pilot inadvertently climbs into IMC [instrument meteorological conditions] trying to avoid a cloud bank or flies into clouds, he can press the SAS button on the panel or press and hold the force trim release button on the cyclic for 1.5 seconds and HeliSAS will engage. The pilot can then remove his or her hand from the cyclic; and the aircraft will roll to zero-degree roll angle and two-degrees nose-up, establishing a safe and stable attitude. This allows the pilot to gather his wits, and by using the upper autopilot modes—altitude hold [ALT] and heading [HDG] or navigation [NAV]—to fly out of the clouds.”

A Safe and Stable Attitude

The “safe and stable attitude” capability of HeliSAS appears to have been a primary factor in saving three crewmembers and one patient from injury and possibly death on January 12 of this year. The four were onboard a HeliSAS-equipped, single-pilot Bell 206L4. In this medical configuration, the feet-end of the patient’s stretcher extends into cockpit, replacing the left-side pilot seat and controls.

According to a “Mishap Notification” posted on the Concern Network, “An Air Evac Lifeteam flight crew was transporting a patient from a scene when the pilot suffered a medical emergency that impaired his ability to operate the aircraft. The pilot had engaged the stability augmentation system and autopilot systems (HeliSAS) after departure from the scene and moments later stopped responding to the medical crew over the ICS. After several attempts to elicit a response from the pilot, the flight paramedic accessed the cockpit and assisted the pilot, who landed the aircraft safely in a rice field while the flight nurse contacted the company's Operations Control Center. The flight paramedic and nurse performed an emergency shutdown of the aircraft and removed the pilot from the aircraft. Additional resources were dispatched to transport the patient and the pilot to appropriate medical facilities.”

[The Concern Network was created in 1984 by the now-named Air & Surface Transport Nurses Association as a means of collecting and distributing information about a variety of airmedical and critical-care, ground transport mishaps. For privacy reasons, Air Evac Lifeteam declined to provide additional information about this incident for this article.]

Genesys offers HeliSAS in three configurations: SAS only; SAS with beep trim; and SAS with two-axis autopilot and beep trim. The company’s OH-58, being a demo and test aircraft, has the latter configuration.

Above 40 knots, the pilot can engage the upper modes HDG (heading), NAV (navigation) and ALT (altitude). If the aircraft has a heading bug or HSI, the autopilot’s HDG mode will follow it; NAV mode can also hold a GPS track. The pilot selects an airport or waypoint in NAV mode and the HeliSAS will fly to the destination. When in ALT mode, raising the collective increases airspeed, while lowering the collective decreases airspeed.

“In the upper modes,” Howard continued, “HeliSAS can fly an approach—ILS or LPV. If you are given vectors to intercept, you can have HeliSAS in HDG and ALT hold and turn to the intercept heading and press NAV. NAV will arm—HDG and ALT hold remain on—and as the CDI comes in, HDG releases and NAV steers the course. Pressing VRT arms vertical navigation for either the localizer or GPS and then captures the glide slope.”

Slipping the Surly Bounds of Earth

Our demonstration flight during HeliExpo 2018 took us from Henderson Executive Airport (HSH) to Boulder City Municipal Airport (BLD) and back. Howard, the pilot-in-command, flew from the right seat with Chuck in the left front seat; Thurber and I rode in the back. At Boulder City Airport, Chuck and I switched seats for the return flight to Henderson. During both legs, Howard demonstrated the various HeliSAS functions and then had Chuck and me try them while he talked us through the maneuvers. The weather was severe clear, but with a steady wind of 15 to 25 knots that became turbulent over and downwind of the rocky hills between the two airports. Total flight time was about an hour.

At Boulder City, I lifted into a hover with HeliSAS and the force trim engaged. In gusty wind it took me a while to stabilize the hover both with and without depressing the trim button to compensate for the wind. After few minutes' practice this became a bit easier, but I still felt rusty.

Howard had me do a normal takeoff straight ahead into the wind and then he selected heading hold (HDG) on the HeliSAS panel, which is below the center console in the OH-58. A pilot in the right seat can easily push the HeliSAS buttons with his left hand while keeping his right hand on the cyclic. This action is more awkward for a left-seat pilot, especially in turbulent conditions. I did not yet feel comfortable holding the cyclic with my left hand and looking down and to the right to find the HDG button on the panel. So I gratefully accepted Howard’s suggestion that he do the button-pushing.

As we flew toward Henderson, Howard showed me the system’s “recovery from inadvertent IMC” capability. He had me put the aircraft nose-up and in 30-degree left bank, and then told me to press and hold the force trim release (FTR) button one-and-a-half seconds (“Should I count?” I thought) until I felt HeliSAS taking control of the cyclic, at which time I should let go of it. I did as told, although I kept my hand close to the cyclic grip, and watched as HeliSAS rolled the helicopter wings level and settled into a slight nose-up attitude. I kept my left hand on the collective to control altitude. Seeing how well this worked, I asked to try it again. This time I took my right hand completely away from the cyclic. Cool!

OH-58A+ Kiowa on the ramp
A former U.S. Army OH-58A+ Kiowa serves as the Genesys flight-test and demo helicopter. (Photo: R. Randall Padfield)

I did more maneuvering while heading in the general direction of Henderson, and soon felt comfortable with HeliSAS doing most of the work. Traffic and wind at Henderson (and another demo flight for Howard) cancelled our planned instrument approach to the airport, but I have no doubt that the NAV, BC and VRT functions would have worked, too, as they had on my previous HeliSAS flight in 2013. Howard took control to safely bring N762MF back to its parking spot on the southernmost Henderson ramp.

Later, Luster told me, “We used to hear objections from owners who would say, ‘I got my pilot’s license to fly. Why would I want an autopilot?’ And we would try to get them to understand that HeliSAS is the augmentation system that saves lives.” But more recently there seems to be a change of mentality in the marketplace, she continued. “We’ve had helicopter owners come to us at trade shows and say, ‘If I hadn’t had HeliSAS installed, I would be dead now.’”

Luster concluded, “We offer the stability augmentation only, or stability augmentation with autopilot. All VFR. We’re continuing to add capabilities to the system. We’ve improved some of the handling characteristics. We worked with EFIS manufacturers to enable altitude preselect on their EFIS displays and feed that to the HeliSAS. Our most recent STC was for the EC120; we changed the VERT button to an airspeed button. Push it once and it holds airspeed; push it twice and it holds vertical speed.”

Airframes currently STC’d for HeliSAS are the Bell 206B/L and 407, the AS350 series, the EC120, EC130B4, EC130T2, and the Robinson R44 and R66. The total worldwide market for these airframes is roughly 12,800, Luster said.