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Flying the Phenom 300
Eduardo Menini, a senior test pilot with Embraer, walked us around EMB 505-101, the first production-conforming aircraft to enter the flight test program, during the preflight inspection. He pointed out some of the Phenom 300’s high-utilization and operator-friendly design features.
Basic maintenance intervals, for instance, are 12 months or 600 flight hours. The aircraft’s MSG 3 maintenance-friendly design makes it possible to replace windshields in two hours. The third-generation L-3 SmartProbes eliminate tubes and pipes between probes and ADC boxes. All antennas and other external sensors, including the SmartProbes, can be changed from outside the airplane. Gel gaskets eliminate the need to use liquid sealants that must cure before flight.
All flight control cables and linkages are designed so that they cannot be reversed during installation. The front and rear batteries slide out on trays for easy access and replacement. The aircraft uses only one type of grease. The fuel boost pumps have brushless motors for long life and they are mounted in dry canisters so they may be changed without defueling the aircraft. The winglets are mounted with screws, making them easy to remove and replace.
All main electronic and avionics components, including the engine FADECs, are located inside the pressure vessel where they are protected from pressure and temperature extremes. A central maintenance computer (CMC) simplifies fault identification. The CMC can even check autopilot servo torque, thereby eliminating the need to remove them for bench tests.
The Phenom 300 is designed for easy access to systems and high-frequency utilization, similar to Embraer’s jetliners. The design expedites the crew’s preflight inspections. Credit: EMBRAER
Most line service tasks are easy. If needed, the oxygen bottle may be refilled through a port in the nose baggage compartment. The single-point pressure refueling panel has a utility light for nighttime operations and it has a selectable refill quantity feature. Engine oil quantity can be checked with sight glasses visible through doors in the nacelles. The toilet is externally serviced. The baggage compartment has a large, counter-balanced swing-up door and the sill is waist high for easy loading.
Menini, though, didn’t show us how to install and remove the landing gear pins without getting dirty. The gear must be pinned if the aircraft is towed and unpinned prior to flight. One must go on hands and knees to get access to the pins in the main landing gear wheel wells. The nose gear pin is mounted high in its wheel well, so it’s almost necessary to lie down on the ramp to reach it.
In addition, while the toilet is externally serviced, fresh water reservoirs in the galley and lavatory must be replenished internally. Those systems weren’t installed in the flight test aircraft we flew, so we could not assess the associated workload issues.
Still, because of all the flight test equipment and a ballast tank, 505-001 had an empty weight of 11,900 pounds, or about 450 pounds heavier than a completed production aircraft with standard equipment.
With my strapping into the left seat and Menini in the right, flight test engineer Leandro Bigarella at the console and Daniel Bachman at the videocam, the aircraft’s zero fuel weight was 13,000 pounds, including forward water ballast to keep it in the c.g. envelope. Loaded with 4,400 pounds of fuel, ramp weight was 17,400 pounds.
Bigarella computed takeoff V speeds for Flaps 1 (eight degrees) and a 17,300-pound takeoff weight or 96 percent of MTOW. He called out 107 KIAS for the V1 decision speed, 110 KIAS for rotation and 120 KIAS for the V2 OEI takeoff safety speed, based upon São José dos Campos’ 2,119-foot field elevation, 29.94 inch Hg barometer setting and 20°C OAT. Computed takeoff distance was 3,050 feet. Estimated OEI takeoff field length over a 35-foot obstacle was not available.
We plugged in ground power to save the batteries and to allow all the onboard test equipment to warm up before engine start. During cold weather operations, the batteries must be warmed to at least 0°C before engine start, even if external power is available. This assures adequate battery performance to meet the 45-minute emergency power requirement.
Menini pointed out that the aircraft’s automated electrical system requires only one button push to connect external power. All other system switches can be left in the “on” or “automatic” positions.
After electrical power is turned on, pre-start checks are quick, consisting of fire protection, baggage compartment smoke detector, annunciator light, stall protection and ice protection checks performed with a rotary test switch. Embraer also requires that the crew manually set in OAT as a reference for the FADECs, a procedure that dates back to the EMB-145. This provides a backup reference for the FADEC’s temperature sensor in the engine inlet. We also checked individual battery voltages to assure ample power reserves.
Once the cabin door was closed, we turned first the right, then the left, engine operating switch from Off to Run to Start. The vapor-cycle air conditioner automatically turned off during start to conserve electrical power. The FADECs handled all the starting tasks as we monitored the engine and systems indications on the MFD.
After engine start, the air-conditioning automatically came online and we disconnected external power. We checked battery reserve power, free control movement and proper takeoff trim and flap setting. We verified that the FMS had programmed in the landing field elevation of São José dos Campos for proper cabin depressurization upon our return and set Flaps 1, verifying the flap movement on the MFD.
Getting the aircraft to roll out of the chocks required very little thrust increase. Wheel brake action was smooth with the cold carbon brakes, but the aircraft required heavy pedal pressure, typical for Embraer aircraft. Nosewheel steering authority through the rudder pedals was adequate for most taxi maneuvering, but differential braking and thrust was required for tight maneuvering. Since the aircraft doesn’t have a tight turning radius, care must be taken when taxiing on crowded ramps.
We also checked the emergency brakes. Pulling up partially on the parking brake T handle actuates the emergency brakes smoothly and progressively through a secondary hydraulic circuit, but no differential braking or anti-skid is available.
Prior to takeoff, Menini pressed the takeoff configuration check button and we heard the integrated Prodigy avionics system say, “Takeoff OK,” verifying that flaps, spoilers, pitch trim and parking brake were in the proper position for departure. Having 10,200 feet of pavement available on Runway 15, we were not concerned by accelerate-stop distance. Using the Flaps 1 configuration results in lower drag than Flaps 2, thereby improving second-segment OEI climb performance.
On the runway centerline, we pushed up the throttles to the takeoff and go-around (TOGA) position, the third detent in the quadrant. There’s also a maximum thrust position, forward of the TOGA detent, but how much extra thrust it will command, and under what conditions, has yet to be determined.
Acceleration was smooth, but not sporty. Rotation forces were moderate, if not hefty, another trait of Embraer jets. We rotated to 12 degrees nose up and retracted the gear with a positive rate of climb. In the process, we had to increase pitch attitude to 25 degrees to prevent exceeding the 140 KIAS Vlo limit speed imposed on the test aircraft. Production aircraft will have more-robust landing gear doors and thus a considerably higher landing gear operating speed.
At 400 feet agl, we accelerated to 136 KIAS and retracted the flaps. We continued the climb, leveling off at 5,000 feet for air traffic control while we exited the local traffic area to the northeast. We noted that while the aircraft has a heavy stick force per g, it’s not particularly sensitive in pitch to speed or configuration changes. Pitch and roll control forces were moderate, well harmonized and more in line with what we’d expect from a midsize jet than a light jet.
Winter storm clouds created a choppy ride up to 10,000 feet, but the flexible wing structure seemed to soak up most of the bumps. At that point, we noted an anomaly in the weather radar display. Garmin has yet to develop the capability of overlaying the flight plan route on the onboard radar display. That makes it difficult to determine if the programmed flight plan track will steer clear of storm clouds. However, the flight plan track is displayed together with XM radio weather graphics, if one is operating in the continental U.S. coverage area.
When stabilized at 10,000 feet, we recorded a weight of 16,975 pounds, started the clock and began a direct climb to FL 450. Menini said best climb performance would be obtained using a 225 KIAS/0.60 IMN climb schedule.
During the climb we checked roll control response, noting heavy control forces at maximum yoke deflection, but achieving 60-degree-per-second roll response, according to Bigarella’s instruments. The effect of the roll spoilers on roll rate and roll control effort seemed negligible.
Later, we checked short-period stability, noting that the aircraft is well damped. We also noted that the current version of SmartProbe software has very little dampening, thus the VSI readout often jumped ±50 feet with no change in aircraft attitude or speed.
Eight- to 10-degree warmer-than-standard outside air temperatures during most of the climb didn’t help climb performance. OAT didn’t cool off to ISA until we crossed FL 400. But OAT dropped to ISA-6.5°C by the time we leveled at FL 450, stopping the clock at 22 minutes and recording a 550-pound fuel burn for the climb.
We accelerated to 0.66 Mach long-range cruise at FL 450. We attempted to use the aircraft’s cruise speed control (CSC) function, a feature that provides limited authority thrust adjustment, with the trim range of the FADECs, when altitude hold is engaged. But CSC wouldn’t hold speed without uncoupling, so it appeared to need more development work before it’s ready for service.
Once stable, we recorded 372 KTAS while burning 840 pph at a weight of 16,340 pounds (91 percent of MTOW) in ISA-6.5°C conditions. We also noted that the aircraft’s pitch trim seemed a touch sensitive, providing plenty of pitch trim change with very little movement of the trim switch.
We then evaluated high-speed buffet margins. We rolled into an increasing angle of bank, holding altitude. Flight test restrictions limited us to using a maximum 45-degree angle of bank. But we still recorded 1.5 g of load at 16,200 pounds with no evidence of buffet.
Capt. Menini demonstrated the operation of the counter-sprung airstair door. Credit: EMBRAER
We also checked spiral stability. When we rolled into bank angles up to 30 degrees, the aircraft gradually returned to wings level. At bank angles greater than 30 degrees, the aircraft slowly would roll off.
Long-period pitch (phugoid) stability proved to be a strong point for the aircraft. We trimmed for cruise at 180 KIAS at FL 435, pulled up until the speed decreased to 156 KIAS and let go of the yoke. After five up-and-down cycles, averaging 74-second periods, aerodynamic damping almost had eliminated the porpoising.
The Phenom 300 also exhibits strong Dutch roll damping, a product of its having primary and secondary rudder dual yaw dampers. While the primary rudder yaw damper can be shut off, the secondary dorsal fin rudder is activated automatically anytime the primary yaw damper is inoperative and it cannot be shut off.
After our checks at high altitude, we descended to FL 300 for a high-speed cruise check. On the way down, we evaluated the performance of the two-position air brakes. When extended, the air brakes produce moderate buffet and mild pitch-up. Retracting them produces the opposite effect. A software interlock prevents air brake extension with the flaps extended.
Setting the throttles at max cruise at FL 300, the aircraft stabilized at 448 KTAS at a weight of 16,000 pounds (89 percent of MTOW) while burning 1,586 pph in ISA+6.5°C conditions. The final static source error correction curves have yet to be programmed into the SmartProbes, so the aircraft actually was cruising at 453 KTAS, according to the onboard flight test instrumentation. Book cruise performance predicted 451 KTAS under those conditions, Bigarella said. Both numbers back up Embraer’s claim that the aircraft will cruise at 450 KTAS at 90 percent of MTOW.
Descending to 15,000 feet, we put the aircraft through some basic air work maneuvers. A couple of near 60-degree bank angle turns revealed that the aircraft had the heavy stick force per g pitch control feel that’s characteristic of most Embraer aircraft with conventional flight controls.
Make a note: Trim into the turn or be prepared to use both hands on the yoke for your checkride.
Stall behavior was docile and predictable. At a weight of 15,870 pounds, we trimmed the aircraft to 122 KIAS in the clean configuration, equivalent to 1.3 Vs1. The stick pusher fired at 90 KIAS (94 KCAS) or 24.4 degrees AOA. Repeating the maneuver at a weight of 15,760 pounds with gear and flaps down, we trimmed to 111 KIAS or 1.3 Vso. Descending 500 feet and leveling off, the stick pusher fired at 82 KIAS (86 KCAS) or 22.7 degrees AOA. There was no tendency to roll off or yaw in either configuration during the maneuvers, but altitude loss was considerable because of the stick pusher. These are not conditions one would want to encounter at pattern altitudes.
Returning to São José dos Campos for pattern work, we coupled the autopilot and let the Prodigy system fly an FMS to ILS approach to Runway 15. Lateral and vertical navigation were very smooth throughout the procedure, with the multiple waypoint VNAV feature reducing much of the workload. However, both vertical and lateral navigation modes seemed a little soft in response, favoring smoothness over precision guidance.
Once the aircraft eventually stabilized on the 155-degree magnetic inbound course, a change in HSI course deviation needle from magenta to green signified the transition from FMS to ILS guidance. We clicked off the autopilot to get a feel for the aircraft during the approach. We again observed that the aircraft seemed to have somewhat overly sensitive pitch trim, yet was comparatively numb in speed stability. Thus, airspeed excursions of 10 knots or more didn’t result in much pitch force change.
Extending the landing gear and flaps produced very little pitch change. We bugged 110 KIAS for Vref for the Flaps 3 (26 degrees) configuration at a weight of 15,500 pounds. Final flight tests evaluating the use of full flaps on landing performance were not yet complete, so we couldn’t use that configuration.
Over the threshold, we reduced power to idle and started to let the aircraft decelerate for the landing touchdown. In retrospect, we should have chopped the power sooner. The aircraft had excess airspeed in the flare, resulting in a long float to touchdown.
Menini reconfigured the aircraft to Flaps 1 (eight degrees) and set the pitch trim into the takeoff position. We followed through with a touch-and-go, turning left downwind into the VFR pattern. This was followed by a normal touch-and-go.
The next pattern was designed to evaluate the aircraft’s OEI performance, especially its balked landing performance characteristics. Menini pulled back the right throttle on downwind, we simulated calling for the engine failure check and configured the aircraft for a simulated single-engine landing. Again we used Flaps 3 (26 degrees), but flew the approach at Vref+10. There were ample power reserves on approach.
When we neared 200 feet agl, we executed a balked landing. As we advanced the thrust lever to TOGA, Bigarella recorded a maximum 110 pounds of pedal force, indicating that the spring-loaded rudder boost system was helping to reduce pedal effort. As we rotated, we moved the flap lever to Flaps 2 and retracted the gear with a positive rate of climb. Changing to the Flaps 2 position, though, strictly was a procedural step. It didn’t change flap deflection from 26 degrees, so the aircraft climbed very poorly until we moved the lever to the Flaps 1 (eight degrees) position. We concluded that most pilots will want to use Flaps 1 for routine takeoffs because of better OEI climb performance. Flaps 2 will be better suited to light takeoff weights and very short runway operations.
The Phenom 300 features brake-by-wire with high-capacity carbon heat packs. Pedal pressure, similar the Embraer’s jetliners, is heavy but braking action is very smooth. Credit: EMBRAER
Once we climbed to flap retraction altitude, we cleaned up the aircraft and we matched the throttle positions in preparation for a normal landing, which followed. We then taxied back to Runway 15 in preparation for a simulated OEI takeoff. At a weight of 15,200 pounds and based upon using Flaps 1, Bigarella computed V speeds of 98 KIAS for V1, 103 KIAS for rotation, 115 KIAS for V2 and 127 KIAS for flap retraction.
Menini pulled back the right throttle at 93 KIAS, resulting in noticeable yaw as the aircraft reached V1. We countered with opposite rudder to maintain directional control. Bigarella recorded a rudder force of 100 pounds.
We initially rotated to 12 degrees and retracted the landing gear with a positive rate of climb. At this comparatively mid weight, the aircraft had strong OEI climb performance. We climbed to flap retraction altitude, cleaned up the aircraft and returned for a normal, albeit maximum effort landing.
Based upon a 15,000-pound landing weight and using Flaps 2, Bigarella computed a 110 KIAS Vref speed. Rolling to final, we delayed reducing thrust until reaching the threshold. Again, this resulted in excess airspeed in the flare and delayed touchdown. The aircraft decelerated smartly, with little tendency to engage the anti-skid function above 60 knots. The maneuver reminded us that Embraer aircraft require comparatively heavy pedal force to achieve maximum braking performance.
After the maximum effort landing, the carbon brakes were quite warm and they exhibited some jerkiness as we taxied back to Embraer’s delivery center. Menini said that was expected and that braking action is smooth when they are cool. Total fuel burn for the two-hour, 24-minute mission was 2,500 pounds.
Final Steps Toward Certification and Entry Into Service
Embraer now has four production-conforming aircraft in the flight test program, racing toward final Brazilian ANAC and FAA type certification late this year. All flight test data collected up to September 2009 indicate that the aircraft will meet or beat Embraer’s projections. Speed, range and sea-level runway performance numbers are on target. Hot-and-high takeoff performance appears to exceed the original estimates by a wide margin.
Embraer has been working closely with training services partner CAE to develop an FAR Part 142 training system. The first full-flight simulators will be installed at CAE locations in Dallas and Burgess Hill, United Kingdom this year. CAE and Embraer plan to open a second U.S. training center in Florida or the Northeast United States in 2010. But it’s not clear if the simulator will earn full FAA approval by the end of this year. Much the same as with the Phenom 100, the first Phenom 300 operators may have to train their pilots in their aircraft until the simulators are certified.
Officials concede that the Phenom 300 development program is about two weeks behind schedule, but are confident they will earn TC and start initial customer deliveries in the fourth quarter of the year.
That’s good news for Phenom 300 customers, including Flight Options, which has ordered 100, Executive Airshare with four orders and four options, Falcon Aviation Services of Abu Dhabi with six orders and four options, Eagle Creek Aviation Services with four positions and Dusseldorf-based Vibroair with two orders. Embraer won’t release the total number of orders it has for the aircraft, but the large block from fractional operator Flight Options could be spread out over several years because of softness in the business jet market.
Long term, though, the Phenom 300 should be a strong contender in the light jet market because of its price, cabin, performance and fuel efficiency, plus its airliner-inspired, maintenance-friendly design. In addition, Embraer’s aftermarket product support is earning high marks from Phenom 100 and Legacy 600 customers, so that reputation should help bolster Phenom 300 sales. Two levels of Embraer Executive Care will be offered, with the standard service providing just parts and freight and the enhanced service providing parts, freight, both scheduled and unscheduled labor, and emergency field service. Pratt & Whitney Canada will offer its Eagle Service Plan power-by-the-hour program to cover the engines.
Quite clearly, Embraer is making a major investment in the business aircraft market, making bold moves to unseat long established firms such as Bombardier, Cessna and Hawker Beechcraft from their positions of dominance. The design of the Phenom 300 demonstrates Embraer’s engineering muscle. The Phenom 300’s airliner toughness and 28,000-hour design life also could make some other light jets seem like spoiled prom queens in comparison. And should something break, Embraer’s growing commitment to product support is second to none. That all bodes well for the Phenom 300.
The business jet industry, particularly the light jet sector, is forecast to rebound slowly as the economy recovers. And with its Phenoms and other executive aircraft models, in production or in development, Embraer is becoming well positioned to seize a significant share of this sector over the next several years.
