Embraer has earned a reputation in the business aircraft industry for being an innovator in the segment, as evidenced by introduction of fly-by-wire flight controls in the super-midsize class, along with standard synthetic-vision PFDs and next-gen fiber-optic gyros. Now, it’s introducing the E2VS, short for Embraer Enhanced Vision System, a two-part package that includes Rockwell Collins’ HGS-3500 compact head-up guidance systems and its new triple-band EVS-3000 enhanced vision sensor.

The goal is to provide Legacy 450 and 500 operators with the ability to fly down to 100 ft. height above touchdown on low visibility, straight-in instrument approaches with a HUD/EVS package that is roughly half the size, weight and cost of current systems.

The HGS-3500 doesn’t have a bulky overhead projector, so it will fit into small and midsize business jets. The unit integrates the image generator and combiner glass window into a single space-saving package mounted to the cockpit overhead structure just aft of the sun visor. The head-up guidance assembly is fully integrated with Rockwell Collins’ Pro Line Fusion, so it doesn’t need a stand-alone computer box. In its place, a single, slim HGS-3500 LRU remote card plugs into the Pro Line Fusion’s integrated avionics processor computer chassis, not unlike adding a peripheral into a desktop computer slot.

The triple-band, uncooled EVS-3000 camera, mounted in the nose of the aircraft, also breaks new ground. It combines an ultra-sensitive day/night videocam, a short-wave IR sensor to detect incandescent airport lights and a long-wave IR sensor to differentiate between the heat signatures of animals, pavement, paint markings and vegetation. Unlike conventional indium antimonide (InSb) infrared detectors, the EVS-3000’s two IR sensors don’t need cryogenic cooling. Eliminating the refrigerator machinery greatly reduces scheduled maintenance tasks and life-cycle costs, as well as boost reliability by an order of magnitude.

Since the system was first announced, it has undergone many iterative upgrades to improve image contrast ratio, display resolution and image fusion from its three EVS sensors. Having monitored the development of the system since its inception, we couldn’t wait to go fly with it.

Let’s Go Flying With the E2VS

At Embraer’s Gavião Peixoto test facility, I was assigned to the left seat of EMB550-0002, accompanied by senior test pilot Eduardo Camelier in the right seat and Capt. Luiz E.L. Salgado Ribeiro as safety pilot on the jump seat.

Entering the cockpit, it’s apparent that the HGS-3500 keeps a low profile. It’s easy to climb into the left seat without bumping your head on HUD hardware. And there’s no loss of headroom once seated. The unit is designed for one-hand operation and there’s no need to move one’s head when swinging the combiner glass between stowed and active positions. After belting into the seat, I could reach up with a single hand, release the catch, pivot it down with a twist of the wrist and then swing it forward a few degrees to lock it into position.

The combiner glass is considerably smaller than on Rockwell Collins’ HGS-5000 and -6000 series projector HUDs. The field-of-view also is smaller — 21-deg. vertical by 30-deg. Horizontal, compared with the 30-deg. vertical by 42-deg. horizontal FOV of Rockwell Collins’ largest HUDs. But the pilot’s eyes are closer to the combiner, so the difference doesn’t seem that large. Rockwell Collins says the ideal position is about 6 in. from eye to glass. However, I found it easier to see the entire image when my head was much closer to the combiner. At times, my forehead touched the padded bumper on the HUD assembly. But Camelier cautioned that squeezing up against the combiner actually can reduce the viewable area on the screen because the acute viewing angle of the pilot’s left and right eyes when so close to the screen cuts off part of the viewable image.

The E2VS has soft menu controls that pop up in a window on the PFD, enabling the crew to select automatic/manual background declutter modes, free or caged flight-path vector symbology and on/off controls for EVS and eventually for SVS. There’s another pop-up menu used for manual calibration of the EVS, should it become necessary. This is an automatic function anytime the aircraft is flying above 1,000 ft. AGL, most of the time.

The HGS-3500, similar to other HUDs, also has hard controls, including separate brightness adjustments for HUD symbology and EVS background imagery. One knob is a knurled cylinder and the other is cube-shaped, so they have distinctive tactile feels. The EVS also has on/off button on the base of the flight control sidestick, enabling the pilot to declutter the display when needed, leaving only essential HUD air data, flight-path vector and flight-path vector imagery.

The EVS-3000 starts displaying video and IR imagery within 10 sec. of power-up. That’s quite an improvement over the 5 to 10 min. typically required for a cryo-cooled sensor to come on line. The first image we saw was of the line service technician in front of the aircraft. Because the EVS unit is mounted high in the nose, there was less parallax error between the actual position of the technician and the image displayed on the HUD screen.

Using the EVS, I also could see the taxiway paint stripe on the HUD. It apparently was offset from the actual stripe by a couple of feet because the sensor on the centerline of the nose and the pilot’s eyes are to the left of the nose.

With the EVS-3000’s long-wave IR sensor, pilots often are able to see paint stripes on the tarmac, taxiways and runways better than with unaided vision. The sensor also can detect the thermal signatures of animals, such as rabbits, coyotes or deer.

In addition, the ultra-sensitive videocam may be able to detect images from illuminated airport signs beyond visual range.

Cleared for departure on Runway 20, we advanced thrust, engaged the autothrottles and began takeoff roll. It was easy to see the runway’s centerline stripe image in the HUD and keep the aircraft on track as we accelerated. Admittedly, the PFDs offer all the imagery of the HUD, but you still have to shift focus between head-down and head-up to see and avoid threats that only can be detected by looking outside the airplane.

After takeoff, Camelier dialed in an initial heading of 120 deg. and we first climbed to 5,000 ft. as assigned, then up to FL 170. Using the HUD’s flight director, we followed the guidance cues and flew over the nearby town of Araraquara in the mainly agrarian region north northwest of São Paulo. Several farmers were burning off sugar cane stumps in their fields, causing some blooming of the IR imagery in the HUD. A future software update will quell most of the image blooming from such hot spots.

I also noticed dots of light in the top of the HUD background imagery. Camelier pointed out that the dots were stars, too faint to see with the naked eye in the evening haze but bright enough to be detected by the sensitive day/night videocam.

The videocam also could detect the xenon strobe lights of an aircraft about 5 mi. from ours. As the intruder approached closer, I could see the heat signature from its turbine engine exhaust that was detected by the IR sensors.

Next, we proceeded direct to KOTRU intersection and then southeast on W51 toward São José dos Campos (SBSJ) for pattern work. We paused long enough to fly up the Rio Paraiba do Sul valley northeast of the airport to explore more of the E2VS’s capabilities. The IR sensors detected the faintest clouds below us along with heat plumes from factory and refinery smokestacks. We did not fly low enough for the EVS to detect terrain. Flying well above the hills, the SVS background imagery will provide improved situational awareness when it’s available.

We then flew a couple of ILS approaches to SBSJ’s Runway 15. Visual meteorological conditions prevailed. Even so, the advantages of flying an instrument procedure with a HUD were quite clear. Not only did it provide all the air data and flight guidance information needed to fly the approach, I also could look through the combiner and see the VASI, approach and flashing strobe lights to verify our position relative to the runway threshold. Align the flight-path vector, VASI lights and 3-deg. nose-down reference and you’re virtually guaranteed a precision touchdown on the stripes, assuming you’ve refined your flare technique.

A word of caution applies here. Using the HGS-3500, as with any HUD, lures the pilot into tunnel vision. It’s tempting to restrict one’s scan to that tiny 21-deg. by 30-deg. window. When making the transition from glidepath to landing flare below 50 ft. HAT, it’s still essential to use one’s peripheral vision to pick up cues to make contact with the pavement smoothly and precisely. Using the HUD’s flight-path vector cue alone can result in an embarrassing ker-plump or excessive float.

Camelier, though, said he’s learned to use the flight-path vector as a primary reference for spot landings. In the flare, he just adjusts nose attitude to reduce the angle of descent to 1 deg. and he achieves consistently smooth and precise touchdowns on the stripes.

E2VS Value Proposition

It’s been a quarter century since the Flight Safety Foundation conducted its conclusive study on the efficacy of HUDs presented in “Head-Up Guidance System Technology — A Powerful Tool for Accident Prevention” (FSF/SP-91/01). Published as a report in the September 1991 issue of the foundation’s Flight Safety Digest, the study concludes that HUDs provide “critical aircraft flight guidance and performance information” as they offer “aircraft operators an excellent tool to substantially reduce crew error” that might have “prevented or positively influenced” almost one-third of fatal civil jet transport accidents.

Quite candidly, we’ve been strong advocates for head-up displays for decades. These small “see through” screens or windows enable pilots to view aircraft energy state, flight director, air data and navigation system status annunciations while looking out the windshield. Before flying the Legacy 500 with the E2VS, I had flown a couple of dozen aircraft, including jetliners, large-cabin business jets, military transports, trainers and light attack aircraft, and strike fighters, fitted with head-up displays. Using an early generation HUD, I conducted simulated CAT III ILS approaches in a Falcon 2000 with a special electro-chromic pane just behind the pilot’s windshield that could change from clear to WOXOF cloud blur at the touch of a button.

Each time using HUDs, I’ve been impressed with their effectiveness in improving situational awareness, in helping to fly with greater precision and smoothness, in helping stay heads up and eyes out of the cockpit looking for potential traffic and terrain threats.

So, it’s easy to be so bullish on the E2VS. Embraer isn’t ready to quote a price for either or both of the E2VS components, but insiders say the HGS-3500 plus EVS-3000 is likely to add approximately $500,000 to the final tally. At that price point, it’s half the cost of a conventional projector HUD complemented by a cryo-cooled InSb IR camera.

So, a first impression from flying with the system is that field-of-view, image resolution, symbology response and background refresh rates aren’t quite on a par with traditional million-dollar class, approved enhanced flight vision systems (EFVS). But the E2VS certainly has the potential to earn EFVS certification in its present form. And improvements are slated for the system between now and scheduled certification in mid-2016.

In our opinion, the E2VS is a breakthrough product. It provides nearly all the benefits of EFVS packages installed in large-cabin aircraft while slashing the price in half. EFVS is one of the emerging safety technologies that has potential for significantly reducing fatal accidents in business aircraft, boosting mission completion rates and improving situational awareness.

Embraer has seized the high ground with the E2VS for its new Legacy 450 and 500 jets. Let’s hope that other manufacturers follow its lead by bringing down the cost of EFVS for their customers. 

This article appears in the November 2015 issue of Business & Commercial Aviation with the title "Flying E2VS."