When Airbus entered into a partnership with Bombardier to take a majority stake in the C Series program in October 2017, the European airframer added a brand new 100- to 150-seat single-aisle aircraft to its lineup. Since this tie-up, Airbus has pushed the former C Series program beyond the imagination of most observers. Closing in on total orders for 550 aircraft, the rebranded Airbus A220 is now demonstrating its efficiency by surpassing its original fuel savings and direct operating cost estimates with operators around the world.
This clean-sheet design was developed to tackle the lower end of the Airbus and Boeing lines, the A318 and 737-600, respectively. The final green light was given to the C Series program when the Pratt & Whitney PurePower PW1000G geared turbofan family was introduced—this development offered an “out-of-the-box” fuel savings of 15 percent. Aerodynamic efficiencies and the use of advanced weight-saving material bumped the savings up to 20 percent over legacy airliners in this space.
There are now 72 Airbus A220s in service with five operators. Available in two sizes, depending on configuration, the A220-100 seats between 100 and 130 passengers and the A220-300 has 130 to 160 seats.
Several key features differentiate the A220 from legacy airliners. Considering that most aircraft in this class were certified 20 or more years ago, the A220 takes full advantage of advanced technologies, including Fadec-controlled geared turbofan engines, a fly-by-wire (FBW) flight control system, and fully integrated avionics. For the pilot, the main purpose of this advanced technology is to reduce workload and enhance safety.
To experience the aircraft firsthand, AIN was invited to Wichita, Kansas, to fly an A220-100. Before the trip to Wichita, a familiarization course was completed in Montreal that included a complete computer-based training program and simulator training.
From the start, I soon learned that the A220 is light years ahead in technology, automation, and operating philosophies than earlier jetliners. In fact, the FBW system and Rockwell Collins ProLine Fusion avionics on the A220 are more closely related to the new Global 7500 business jet than any other airliner. The main difference is a leap towards simplicity, safety, and highly integrated systems.
A few days after the familiarization course in Montreal earlier this month, I would again find myself in the cockpit of an A220. This time, I visited the flight test center in Wichita to fly FTV-2—the second A220-100 prototype.
The crew for our test flight comprised of experimental test pilots Captain Dave Lewandowski and Captain Andy Litavniks and flight test engineer Mark King. Following our preflight briefing, we walked out to the flight line to begin preparing the A220 for the flight.
For the preflight, I joined Lewandowski to complete the walk-around inspection. For the most part, the walk-around is like any other airliner. However, as we approached the PW1525G, the large fan section and contoured composite blades really stood out. The PW1525G is the highest-power variant available for the A220-100 and is rated at 23,300 pounds of thrust with an additional 5 percent reserve.
With the preflight complete, we settled into the cockpit. The A220 flight deck is huge—and it’s clean, uncluttered, and provides a great workspace.
The Rockwell Collins ProLine Fusion avionics are the heart of this cockpit. Five large 15.1-inch LCD display units take center stage; each is configurable to meet a pilot’s needs based on phase of flight. An optional HUD for both the captain and first officer is available that replicates the symbology from the primary flight display, easing the transition to an outside view and reducing training requirements.
On this flight, Lewandowski sat in the right seat to guide me through our test card, while Litavniks served as a safety pilot in the observer seat and gave valuable input and assistance. Smith, the flight test engineer, provided additional performance data when needed. I occupied the left seat during the three-hour evaluation flight.
Engine start on the A220 is fully automated. The start sequence is initiated by placing the engine start switch to “run” and everything from normal to non-normal starts is completed automatically. Total start time for both engines was just under three minutes. Next, we shut down the APU, performed a flight control check, cleared the ground crew, and were ready to taxi.
Taxing the A220 out of the flight test center to Wichita Dwight D. Eisenhower National Airport’s (KICT) Runway 19R took little effort. The aircraft with idle thrust taxied at a manageable speed and the electric brakes and nose steering were responsive, but not too touchy.
Weather for the flight was typical for Wichita in the spring—VFR with a high broken layer of clouds and strong southerly winds from 180 degrees at 15 knots, with gusts to 24. Takeoff weight was 107,700 pounds—about 80 percent of mtow—with 20,950 pounds of fuel onboard.
Cleared for takeoff, I lined the aircraft up with the centerline and advanced the thrust levers to 55 percent N1. Once the N1 stabilized, I further advanced the thrust until the autothrottle engaged. Acceleration was brisk and the airspeed soon reached Vr. I then increased back pressure on the sidestick—less than a half inch of travel—and pitched towards the “pitch target marker” on the attitude direction indicator.
During the climb or any other phase of flight, when hand flying the pilot must adjust the pitch trim as speed increases or decreases. On the airspeed tape, there is an “FBW trim speed bug” that is the cue to identify the speed that the aircraft is trimmed for in manual flight.
When the autopilot is engaged, the pitch trim is automatically adjusted. Maximum allowable pitch, according to the flight envelope protections, is 30-degrees nose up and 20-degrees nose down, though this is further limited during takeoff for tailstrike protection.
FBW Demos
In roll, the FBW system has neutral spiral stability up to 30 degrees of bank, and once established the aircraft will maintain its bank once the sidestick is released. Above 30 degrees of bank, the aircraft has positive spiral stability, meaning that when the sidestick is released, the bank will return to 30 degrees. The maximum allowable bank angle is 80 degrees, which is controlled through flight-envelope protections.
Hand flying the A220 is extremely precise. Once the aircraft is properly trimmed, the A220 through its FBW system is rock solid. During the evaluation flight, I hand flew the aircraft up to FL280, and it was nearly effortless.
Level at FL280, the next item on our agenda was to demonstrate the emergency descent mode (EDM). EDM is an automatic function that is active above 25,000 feet. In the event of a rapid depressurization (cabin altitude above 14,500 feet), EDM activates.
EDM automatically engages the autopilot and autothrottles (if not already engaged), selects 15,000 feet on the mode control panel (MCP), and resets “7700” in the transponder. Next, the system will reduce the thrust levers to idle and begin a descent near Vmo/Mmo. The pilots only need to don oxygen mask and deploy the spoilers.
To demonstrate, Lewandowski lifted the guarded EDM switch and manually selected it. At this point, we simulated putting on the oxygen mask and I extended the spoilers to the maximum position; in less than a minute and a half we were level at 15,000 feet—the average descent rate was approximately 9,000 fpm.
Next, we would demonstrate the A220’s low-speed handling characteristics and FBW high-alpha protections (HAP). To begin, the aircraft was configured with landing gear down and Flaps 4. I then began trimming the FWB trim speed bug and set the MCP speed to 124 knots (Vref at this weight). At 124 KIAS, I rolled the aircraft to the right and left at 45 degrees of bank. At this speed and configuration, the aircraft was responsive, with no signs of aerodynamic buffeting.
Continuing with the HAP demo, I next turned off the autothrottles and reduced the thrust levers to idle for a wings-level approach to stall. In pitch, the A220’s sidestick has a soft and hard stop. The main differences between the hard and soft is the level of angle-of-attack and load protections provided. To reach the hard-stop requires an additional 16 pounds of force to move past the soft stop.
By design, HAP will reduce the angle-of-attack to maintain control regardless of what you can throw at it—and I tried practically everything. During this demo, I would pull on the sidestick to the soft stop and then further aft to the hard stop. The aircraft was not pleased with my actions.
First it provided a visual warning on the airspeed tape, followed by an aural warning (“Speed, Speed” and then “Stall, Stall”) and finally a tactile nudge and the lowering of the nose to decrease the angle of attack. It was not possible to stall due to the aircraft’s FBW HAPs.
Additional demonstrations of the HAP included adding bank, a dynamic approach to stall with max thrust and a final attempt in the clean configuration. In each case, I would pull aft on the side stick to reach the hard stop and get the same result—no aerodynamic stall.
Recovering from the airwork portion of the flight, Lewandowski negotiated with ATC to obtain a clearance to the Kansas City International Airport (KMCI) for an autoland demo. Kansas City Center accommodated the request with direct routing to KMCI and a climb to FL290.
Autoland
With the approach brief and checklist complete, we were prepared for the approach into KMCI. The autoland land function on the A220 provides approach tracking, runway alignment, de-crabbing (in a crosswind), landing flare, and runway tracking during rollout. Designed to provide the highest level of approach capability based on system status (automatic up-mode capability), there are no different actions required by the pilots when compared to a normal ILS approach.
Configured with landing gear down and Flaps 4, we calculated a Vapp of 130 knots (Vref of 123 plus five knots for the autothrottle and an additional two knots for gusty conditions). The autopilot and autothrottles performed flawlessly during the entire approach, flare, landing, and rollout, even with a slight crosswind. Autobrakes and full thrust reversers were used to slow the aircraft. Once clear of the runway, we taxied back for another takeoff and return to KICT.
Holding short of Runway 19L at KMCI, we set up for a NADP-1 (close-in noise abatement) departure with Flaps 2. Following a normal takeoff and climb, we leveled off at FL230 for the quick trip back to KICT.
Descending into KICT, we planned and set up for a normal hand-flown ILS to Runway 19R. During the approach, the autothrottle did a nice job maintaining speed in gusty conditions—hand flying an ILS using the HUD made it easy to track the localizer and glideslope. Touchdown was smooth, but a bit long since I initiated the flare too early (a habit from my experience with the larger A300-600).
After taxiing back to the departure end of Runway 19R, we set up for a Flaps 3 takeoff and discussed and planned for a simulated engine failure at 200 feet. After takeoff at an airspeed of approximately V2 plus 10 knots, Lewandowski reduced the right thrust lever to idle. The aircraft yawed slightly to the right, but quickly and easily I was able to maintain runway heading.
During an engine failure, the FBW system will sense the change in yaw and apply rudder in the correct direction. The system applies about half the rudder required to maintain directional control and the pilot does the rest.
On downwind, back to Runway 19R, Lewandowski returned the right engine to normal and I continued around the pattern to perform my final landing without the aid of autopilot, autothrottles, or autobrakes. The approach was flown primarily using the HUD for guidance and the approach and touchdown were normal.
From a pilot’s perspective, the A220 is a wonderful airplane that is safe, efficient, comfortable, and a joy to fly. A recent Airbus study comparing accident rates over the past 50 years shows that each generation of aircraft makes a substantial improvement over the preceding generation. This study points to fourth-generation FBW aircraft with flight envelope protection systems—like the A220—to reduce the likelihood of a loss of control inflight (LOC-I) by 75 percent. From my view and the market’s acceptance, Airbus has got a winner with the A220.
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