Guest Posted May 26, 2017 Share Posted May 26, 2017 For those who might have one coming their way. Flying The A321neo: Technology Upgrades Under The Skin Small but significant changes—not just new engines—set the reengined A321neo apart May 26, 2017Tim Wuerfel | Aviation Week & Space Technology Arriving at Airbus headquarters on the south side of Toulouse-Blagnac Airport, it was clear there was going to be one unexpected factor for our upcoming A321neo test flight: low clouds, rain and a westerly wind at 10C (50F). We were going to have to look for airspace suitable for low-altitude testing, and landings would be on a wet Toulouse runway. On our way to the briefing room, ahead of what would be more than 3 hr. of test flying, we pass the two A321neos used for certification testing, both parked outside Airbus’s flight-center at Blagnac. One of them is powered by the Pratt & Whitney PW1100G, the other by the CFM Leap 1A. At a length of 44.5 m (146 ft.), the A321neo is the longest of the A320neo family, but its larger engines are the distinctive difference from the conventional engine option (CEO) version. They make the aircraft look more balanced and powerful. FLYING THE AIRBUS A231NEO A321neo is the largest member of Airbus’s reengined A320neo family Aircraft is finding success as a replacement for the Boeing 757 Aviation Week flew the Pratt & Whitney PW110G-powered version Pratt and Airbus are working to minimize start times on the engine But the NEO is about more than just putting new engines under old wings, and that is reflected in flight testing, explain Airbus test pilot Capt. Etienne Miche De Malleray and flight-test engineer Sandra Bour-Schaeffer. The new airframe/engine combinations had to undergo intensive testing, including flutter, crosswind landings and minimum unstick speed, which is used during certification to establish other speeds like rotation (VR). As the new engines add about 1.8 metric tons (4,000 lb.) to the aircraft’s dry operating weight, areas such as engine pylons, wing structure and bleed and oil systems were adapted. Other changes were made to improve the A320neo family by introducing technology developed for the A380 and A350. Certification flight testing turned out to be about three-quarters of the effort required for an all-new aircraft, at more than 4,000 flight hours. The aircraft for our flight, registered as D-AVXA, is powered by PW1100G geared turbofans (GTF). The larger fan diameter, at 2.06 m, and the reduction in number of fan blades to 20 from 36 on the CFM56-5B, are the obvious differences from the CEO. The A321neo is the largest of Airbus’s reengined A320 family, seating up to 236 passengers. Credit: P. PIGEYRE/AIRBUS The higher bypass ratio of 12.5:1, compared to the CFM56’s 6:1, is also immediately visible and accounts for most of the NEO’s lower fuel burn, noise and emissions. On the A321neo, the PW1100G is rated at 32,900 lb. thrust and therefore has about 1,000 lb. more thrust than the CEO, while maximum takeoff weight is unchanged at 93.5 metric tons. Because of the lower fuel consumption, range is increased by 500 nm, or 2 metric tons of extra payload is available. If it used to be easy to turn the fan a little during the preflight walkaround to ensure it is freely moving, the checks are a bit of a workout on the GTF because of the mechanical drag of the fan-drive gear system. The fan will not turn counterclockwise if parked in a tailwind, so no boarding passengers will be wondering what the rattling means. The aircraft does not have to be repositioned out of a strong tailwind for engine start. The fan-cowl door latches underneath the engine are a new feature and send a message to the electronic centralized aircraft monitoring (ECAM) screen in the cockpit if two out of three latches are not properly closed after maintenance. The test aircraft had an unfinished cabin with water tanks for ballast and an engineering station in the middle of the cabin. In the cockpit, everything looked familiar, except for some test hardware and the optional head-up display. This reduces the minimum required visibility for takeoff to 75-m from 125-m runway visual range. Going through the preflight cockpit checks, I noted two oxygen-pressure indications on the system display (SD). It is optional on the NEO to have separate oxygen bottles for the two pilots, a choice for more redundancy that many customers are taking, Airbus says. On the engine page of the ECAM, there were amber crosses where engine oil quantity is on the CEO. On the NEO, as on the A380 and A350, I had to turn on the full-authority digital engine control (FADEC) ground-power switches on the overhead maintenance panel to check the quantities. Once the engine start sequence began, oil quantity was displayed continuously. The Leap 1A is a conventional turbofan with a high bypass ratio, but the PW1100 has 3:1 reduction gearbox that allows the fan and low-pressure compressor to each operate at optimized speeds. After a recent shutdown, the PW1100G requires cooling to minimize internal temperature differences before restarting. The engine performs an automatic dry crank during the start sequence to avoid a bowed rotor. The length of this “cooling” period, which actually balances the internal temperatures, is dependent on the exhaust gas temperature at last shutdown, ambient temperature and the time since last shutdown. The time until ignition is shown on the engine warning display (EWD) together with the word “Cooling.” Initial A320neo customers together with Airbus have put a lot of effort into reducing the start times and, with the input of Lufthansa’s technical team, a dual-start procedure was created. This is initiated by pushing a new button on the overhead panel. As the dry cranking of the first engine begins, normally No. 2 on the right side, the other “slave” engine is dry-cranked at the same time. When fuel flows in the “master” engine, the dry cranking of the slave engine is stopped so all air pressure from the auxiliary power unit is available for one engine. After completion of the first start sequence, the second engine needs a few seconds of additional cooling before it is ready to start. This saves a lot of dry cranking time and, in the coming months, further small changes by Pratt are expected to deliver normal and known engine start times. Aviation Week’s evaluation pilot found manual control of the A321neo to be more direct and dynamic than that of the A320ceo. Credit: A_Doumenjou/AIRBUS Cleared to taxi toward Runway 32L, I released the parking brake. Our A321neo starts to move without increasing thrust as the ground-idle thrust is higher than I am used to on the CEO to provide the necessary cooling for engine accessories. In preparation for departure, the takeoff configuration test was initiated by pushing the respective button. With the latest software, this internal check now includes the minimum oil temperature, which is a good feature because, at 52C, it is slightly different from the old limitation. We are ready for takeoff at a weight of 71 metric tons and a calculated rotation speed of 134 kt. with flaps in configuration 2 and a reduced takeoff thrust of slightly above 83% N1(low-pressure spool speed). Lining up on the runway, I took a look at the bleed configuration, displayed at the top of the EWD on the NEO. Skies were still overcast with a cloud base at 1,400 ft. I was curious to see the pitch damping at rotation, Airbus’s answer to the certification requirement for tailstrike protection on takeoff and again used on the A380 and A350. But first the sound of the engines caught my attention as the thrust levers were advanced to takeoff power. It is a surprisingly deep sound that gives the impression there is more thrust if needed. Having flown as a passenger in an A320neo, I can say the cabin noise level did not make it necessary to raise one’s voice in conversation while becoming airborne. During the rotation, with a 10-kt. crosswind and a little turbulent air, it was not possible to feel the pitch damping. This is slightly reducing the elevator force at pitch angles above 7 deg. Malleray says a normal, steady rotation is expected just like on the CEO and that if, for any reason, a further pitch input is commanded, it is still possible to rotate the tail into the ground. RELATED CONTENT Podcast: Flying the Airbus A321neo Aviation Week 1987 Pilot Report: Airbus A320 Pilot Report: Flying the 737-8 After retracting gear and flaps, we climbed northwest out of Toulouse into a block of airspace at 8,000-16,000 ft. while I tried to get a feel for the differences in manually flying the NEO compared to the CEO. We had time to look at another new feature: thrust control malfunction logic in the FADEC to detect engine overspeed. There is a shutdown mode while the aircraft is on the ground with stowed reversers to counteract an unwanted runaway if the thrust levers are at idle, but N1 is higher than 60%. An ECAM caution warning appears indicating that the engine has failed. A so-called cutback mode will activate if, while airborne below 15,000 ft. and Mach 0.45, there is an overspeed of an engine. Fuel flow will automatically be cut back to a low preset value. Then it is up to the flight crew to evaluate the situation and shut down the engine if the problem cannot be resolved. The A321neo orderbook is bolstered by airlines buying the aircraft as a replacement for the Boeing 757. Credit: H. Gousse/Airbus Arriving in the reserved airspace, we were finally out of the clouds and continued at varying speeds with different flap settings. The aircraft felt comfortably familiar to an A320ceo pilot. However, the pitch and roll control are more direct and dynamic, and the little allowance or slackness in the CEO is not there. Many Airbus pilots will be flying a mix of CEOs and NEOs for many years, probably even on the same day, so they will have to keep that difference in mind. We continued with more dynamic situations, such as a simulated engine failure during go-around up at 15,000 ft. After my call “go-around, flaps” Malleray reduced the flap setting from 3 to 2 and pulled engine No. 2 back to idle. I reduced the pitch and waited for the beta target reaction on the primary flight display (PFD), which on Airbus aircraft indicates the sideslip (beta) due to the asymmetric thrust. I then slowly added pressure to the left rudder to counter the asymmetric thrust. The maneuver can be flown smoothly and showed no handling differences from the CEO. Due to the design of the new engine, with its larger fan, it delivers more thrust after a few seconds. Airbus compensated for this by adding 5 deg. to the maximum rudder deflection, which is now 30 deg. on the NEO, so minimum control speeds would stay in the same range. We continued with some impressive maneuvers showing the angle-of-attack protections already familiar from the CEO. We flew a ground-proximity-warning-system recovery, which on the Airbus means full back stick, takeoff/go-around (TOGA) power, and letting the flight-envelope protection fly the aircraft at minimum speed and maximum angle of attack of about 11 deg. to avoid a possible obstacle. We traded speed for altitude with an initial rate of climb of more than -5,000 ft./min., and slowed down to about 125 kt. at our weight and altitude. In the avoidance maneuver that followed, I even added full lateral stick input to the back stick, banking the aircraft 45 deg. All these maneuvers showed that the combination of more dynamic control via thesidestick and more powerful engines results in smooth, comfortable control of the aircraft. Malleray then showed me a feature Airbus has added to help during the decrab in a crosswind landing. Aiming at a cloud, we simulated the pilots turning the nose out of the wind during the flare before touching down with a crosswind to align the aircraft with the runway centerline. One of the problems during this complicated maneuver is that the upwind wing is moving faster and therefore has a tendency to rise—which you do not want during landing, as it creates a target for gusts that might push you toward the lee side of centerline. You want wings level for touchdown, with a tendency to have the wing low on the upwind side. So the NEO now gives a little wing-low input during decrab to avoid a rising wing. It was noticeable during our practice, and I like the feature, which will help in gusty and dynamic situations. As with the fly-by-wire system’s gust-alleviation function, it does not relieve the pilot from making distinct steering inputs to assure a safe landing. We climbed to high altitude, catching a glimpse of the Atlantic coastline west of Bordeaux. The A321neo’s engines improve climb performance so the aircraft reaches 31,000 ft. 4 min. earlier and at a 30-nm shorter distance than the CEO at the same maximum weight. Airbus has added a performance improvement package on the wing for low- and high-altitude operations that includes a cover blade behind the spoilers and a lowered leading edge with the wingtip sharklets. Together these changes lead to higher optimum and maximum altitudes compared to the CEO. At lower levels and speeds, the higher mass-flow of the “cold” bypass stream versus the “hot” core stream lead to higher engine thrust, and the greater excess thrust for acceleration during climb was noticeable. After reaching flight level 300, we slowed to “green dot” speed (minimum clean), which is now 216 kt indicated airspeed (KIAS), then accelerated to the maximum operating Mach number of 0.82. At high altitude and high speed, airliners have to be handled carefully, as small pitch changes have large effect. The NEO felt just as sensitive as the CEO, and at low speed it felt similarly well-balanced and easy to control. During our idle-power descent back toward Toulouse, I checked the fuel page on the system display and saw an impressive combined fuel flow of 5 kg/min. (12 lb./min.) for both engines. The descent gave us time to look at a few add-ons to the NEO fuel system. To give early warning, there is a new ECAM message alerting the crew to degraded operation of a fuel filter, generated by detecting a differential in fuel pressure. To warn of possibly contaminated fuel, and if the blockage of both fuel filters is impending, the message “LAND ASAP” is shown in amber. Also on the NEO, there is a new measurement of any abnormal difference in fuel flow and usage between engines, warning of a possible fuel leak. This is another feature I like, as there is a better chance of getting an early warning than the hourly fuel check that is performed on longer flights. Of course, pilots are used to watching the calculated fuel at destination on the flight management system every few minutes. The oil system has also been modified because of the new engines. The gear system on the PW1100G has about 15 quarts more oil for lubrication than the CEO engines. However, the oil quantity indication in the cockpit is kept at similar values to the CEO. There is a new oil-debris-monitoring system that can now detect ferrous and nonferrous particles using an inductive sensor upstream of the main oil filter. Our low-power/low-drag descent was interrupted by air traffic control and the need to be put into sequence for our first approach at Toulouse Airport. We prepared an instrument landing system approach for Runway 32L at 65 metric tons in configuration 3, which is the lower of the two landing-flap settings and unchanged from the CEO. However, on this approach we were going to level off at about 150 ft. above the runway and fly a low pass to demonstrate the runway overrun warning, a new option on the NEO that is also available on the A350. As we flew above the touchdown zone of the 3,500-m-long runway, the system called out first: “If wet, runway too short”—and in fact it was wet. About 2 sec. later, the next warning level came up: “Runway too short.” Both warnings were also shown on the PFD. Had we already touched down, the system would have continued to calculate the remaining runway length. If it was critically short for deceleration, the synthetic voice would have called for “Max braking,” “Max reverse” or even for “Keep max reverse” if the pilot was reducing reverse thrust. After the demo, I pushed the thrust levers into the TOGA notch, climbed back to 4,000 ft. on the northeastern side of the airport, cleaned up the aircraft and prepared for a flaps full landing on Runway 32L. Our gross weight was down to 64 metric tons, and we would see a crosswind of almost 11 kt. on landing, so we would get another look at the decrab support built into the NEO. Pratt & Whitney and Airbus are working to minimize start times for the PW1100G geared turbofans. Credit: Airbus Our approach speed (VAPP) was calculated at 135 kt. with the maximum flap setting, which has been increased to 37 deg. from 35 deg. on the A321neo and to 40 deg. on the A320neo. The change was due to customer demand for better takeoff and landing performance on short runways. With the higher flap settings, VAPP is decreased by 5-6 kt. compared to the CEO, resulting in 5- 7% shorter landing distances. The change means the range from clean speed to the slower VAPP is greater, so you have to be prepared to start speed reduction earlier, particularly with the engines producing higher flight idle thrust and the Sharklets reducing drag. As the engine fan is highly efficient at low speeds and low RPMs, the required power setting for approach is lowered by about 5% N1. On my first approach, I thought the aircraft was not as stable in pitch as I was used to, but our test pilot made clear this was because the power changes I was used to on the CEO were a little bigger than needed on the NEO. Smaller changes of engine thrust will keep you from overcontrolling in speed and pitch. The new engines can be set precisely even at low N1 values. During this final approach, I visually swung to Runway 32R at about 2,000 ft. after flying out of the clouds and then back to 32L at about 1,300 ft. to get another impression of the NEO’s control. After our final landing, I opened the reversers and used idle thrust for a smooth deceleration. Compared to the CEO, the higher ground idle of the NEO engines helped slow us down faster without using the brakes. This keeps the brakes cool for the next departure and will extend the life of the expensive carbon brakes. Stepping off the aircraft, I took another look at the engines. The reduced ground clearance compared to the CEO is noticeable. But the maximum angle to keep them off the ground is reduced by 0.5 deg. and it does not require any change in attention during operation of the NEO. So far, there have been no complaints from customers about foreign object damage due to the reduced ground clearance, Airbus says. RELATED CONTENT Podcast: Flying the Airbus A321neo Aviation Week 1987 Pilot Report: Airbus A320 Pilot Report: Flying the 737-8 Pilots type-rated on the A320 family can fly the NEO after an approved differences course that covers familiarization, technical changes and procedures. This can be done by self-study via computer-based training and takes half a day. The engine manufacturers promised fuel savings of 15% on the A320neo family, and airline experience so far shows these are being achieved—and sometimes exceeded—depending on route structure. Additionally, the NEO is reducing noise footprint by 50% compared with the CEO, and emissions of NOx and CO2 are sharply cut. Because of the new engines, many systems had to be adapted and different limits put in place, but the aircraft will tell you if you are coming close to any of them. Airbus has taken the opportunity to build in technical advances developed for the A380 and A350 but at the same time has managed to keep 95% commonality to the CEO, which is important for the airlines and their maintenance divisions. And how does it fly? It flies like a CEO with some improvements, which is a compliment. Manual control via the sidestick is more reactive, and it feels more direct and dynamic. Due to the number of small changes, as an airline pilot, I would prefer not to fly the CEO and NEO during the same duty time on the same day. But the aircraft is fun to fly, and I am sure pilots will appreciate the technical upgrade. Tim Wuerfel is an A320 captain at Lufthansa, with 14,000 hr. and 6,000 landings. He started flying DC-9s for Aero Lloyd in 1990 and later moved to models such as the DC-8, MD-11 and Boeing 747-200F flying for Lufthansa Cargo. Wuerfel became a Boeing 737 captain at Lufthansa in 2005 and changed to the Airbus A320 in 2013. 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Guest Posted May 26, 2017 Share Posted May 26, 2017 and a second look. FLIGHT TEST: A321neo stretches its legs 26 May, 2017 SOURCE: Flightglobal.com BY: Mike Gerzanics Toulouse Test pilot Michael Gerzanics put the A321neo through its paces for FlightGlobal, and here delivers his verdict When Airbus launched the original A320 in the 1980s, it faced entrenched competition in the narrowbody segment from Boeing and McDonnell Douglas. To answer and perhaps better these rivals, Airbus chose to offer an aircraft with a larger-diameter fuselage and advanced fly-by-wire (FBW) technology. Since then, Airbus has stretched (A321), shrunk (A319) and re-shrunk (A318) its innovative design. And, with the exception of the A318, these models have enjoyed huge success in the market. "Sharklet" wing-tips save some fuel, but the Neo's new engines deliver much greater efficiency and – crucially – longer range Airbus Since the A320's entry into commercial service with Air France in 1988, Airbus has made continual refinements to the series. After initially being delivered with CFM56-5 engines, Airbus quickly introduced a second engine option – the International Aero Engines V2500 – and production of the baseline A320 family continues with the latest versions of both those engines. The stretched A321 arrived in 1994 and Airbus incorporated double-slotted flaps to help low-speed performance of this larger variant. The first major aerodynamic change across the family came in 2012 when the small wing-tip fences were replaced with a 2.4m high blended winglet, dubbed "sharklet", promising fuel savings of as much as 4% on longer routes. Airbus test pilot Etienne Miche de Malleray (right) monitors Gerzanics during engine start Max Kingsley-Jones/FlightGlobal Of late, the narrowbody market has evolved, with carriers desiring to offer service on so-called long, thin routes. Narrowbody transatlantic and Hawaii services from the continental USA are now a reality. The sharklets were a good first step, but further extension of the A321's range would require a more involved and innovative solution. An aircraft's wing loading and thrust-to-weight ratio are two critical parameters in determining its capabilities. The A321's wing area, while increased 2.15m2 by the sharklets, was in effect the limit on available gross weight. How else could the range be increased? While there was no margin for added fuel uplift, a radical increase in fuel efficiency could reduce the total fuel required. Both CFM and Pratt & Whitney were developing engines that promised a 15% reduction in fuel consumption, enough to give the A321 the added range it needed. Versions of both those engines are applied to the A319, A320 and A321 variants, with the new iterations suffixed "neo" (new engine option). The way that CFM and P&W have attained the new efficiency is markedly different. CFM chose a path of incremental improvements and refinements to the CFM56 to develop its Leap turbofan, designated the Leap-1A for the Airbus single-aisles. P&W choose to develop a whole new series of geared turbofan (GTF) engines, dubbed the Pure Power PW1000G family, specifically the PW1100G-JM for the A320neo models. As well as offering significantly increased efficiency, both engines have about 1,000lb (4.5kN) more thrust than their predecessors. STICKY SOLUTION More efficient engines and sharklets gained the range desired by operators, but the circle had yet to be completely squared. Airbus also wanted its more capable offering to have the same or better runway performance as its predecessor. The new engines and associated airframe modifications added 1.8t to empty weight, forcing Airbus to the drawing table for a solution. The A320neo family's sharklets did have a positive effect on take-off performance as they effectively increased the wing's aspect ratio, which directly improved second-segment climb performance. The ground-roll performance for the A321, at all except low-gross-weight conditions, is limited by its layout. Its main gear height and aft fuselage length limits the attainable pitch attitude for take-off. In general, the slower the lift-off speed (Vlof), the shorter the take-off roll. Correspondingly, lowering Vlof lowers the rotation speed Vr. One critical parameter for determining Vr in a geometry-limited aircraft like the A321 is its minimum unstick speed (Vmu). Vmu is the slowest speed the aircraft can lift off the runway and fly away from ground effect. In short, lowering Vmu lowers VLof and Vr, yielding a shorter take-off roll. Tall gear allows good engine ground clearance; double-slotted flaps are an A321 trademark Max Kingsley-Jones/FlightGlobal Further complicating Airbus's task were new requirements levied by certification authorities. Certification speeds would be determined while accounting for average pilot skills, not those of steely-eyed test pilots. To this end, Airbus made two modifications to the pitch flight control axis for the take-off condition to lower the critical Vmu parameter. Unlike Airbus's widebody aircraft, the A320 series has no specific rotation flight control scheme. In legacy A320s, elevator movement is proportional to stick displacement. To ease the task of attaining and maintaining the right pitch attitude, Airbus made pitch response to stick input a rate-command one for take-off. The new scheme should allow pilots to hit the desired 3°/sec rotation rate and easily capture the target pitch attitude. A321s, whether the current engine option (Ceo) or Neo version, have some inherent tail-strike protection due to ground effect as the tailplane and elevator approach the runway surface. As in legacy aircraft, tail-strike avoidance cues are also provided in the Neo's primary flight display. Water barrels are used as ballast for testing Max Kingsley-Jones/FlightGlobal To further enhance safety, Airbus also added a tail-strike protection feature to the A321neo flight control system (FCS) rotation law. Coined an "electronic tail bumper", the FCS system actively prevents a tail-strike as long as the stick is displaced less than three-quarters of the way aft. While full aft stick deflection can still cause a tail-strike, the modifications to the FCS should make real world take-off performance more closely match certification data. TEST MILESTONE At first blush it might seem the flight-test programme for the Neo models could be fairly cursory, as they share 95% parts commonality with their predecessor models. But this was not the case, because the addition of the new heavier, higher-thrust engines necessitated completion of 75% of the test points a new design would have required. Airbus has flown around 4,000h in its certification effort for both powerplant versions of the A320neo and A321neo. Testing of the Leap-powered A319 was under way when FlightGlobal was invited to fly the Pratt-powered A321neo. Late last year, I was fortunate to fly Bombardier's CS300, also equipped with Pratt & Whitney's GTF. Needless to say, I was quite keen to see how the A321neo compared and fared in the skies over southern France. Our preview aircraft – Airbus's Pratt & Whitney-powered A321neo test aircraft (D-AVXA) – was parked at the manufacturer's flight-test centre at Toulouse-Blagnac airport. Before boarding, I did a quick walk around and found the GTF's large-diameter fan most impressive, with the A321's tall main landing gear allowing ample ground clearance for the 2.23m cowling. The cabin was configured for flight test, water barrels to serve as ballast and centre-of-gravity control installed. Midway in the cabin was a two-place flight-test engineer station. On the flightdeck, Etienne Miche de Malleray – Airbus experimental test pilot and head of flight test product design – had already programmed the flight management system. As I strapped into the left seat I found the cockpit to be familiar. One of Airbus's strengths is that its commercial flightdecks have as much in common with each other as possible. With the exception of LCD displays in place of CRTs and an optional HUD, the Neo's flightdeck was essentially unchanged from the A318 I had flown 14 years earlier. A320neo family cockpit will be familiar workplace for current A320 pilots Max Kingsley-Jones/FlightGlobal After completion of the pre-start flows, I noted a “COOLING” time of approximately 2min 40s displayed on the engine-indicating and crew-alerting system display for each engine. Each would have to be dry-motored for that span before fuel could be applied and the start sequence continued. Much has been written about the long start-cycle times of P&W's GTF engines. Longer start times not only affect the starting aircraft; at crowded airports they can delay other aircraft trying to push back or park at their gates. On our flight, the start sequence took just over 7.5min. It should be noted that these were developmental engines and not production representative. Airbus and P&W have made efforts to reduce total time to operationally acceptable levels. While not installed on our aircraft, Airbus has developed a "dual motor" feature for the start sequence. When the first engine is dry-motored, the second engine will also motor and work off its cooling time. For its part, P&W has added a cubic boron nitride coating to the tips of the engine's 11 integrally bladed rotors. The coating creates a better seal and reduces cooling time by about 1min. These efforts are welcome, and according to P&W start times for production engines will be on par with those of the V2500-powered A321s. INCREASED RUDDER AUTHORITY Prior to leaving the chocks, Miche de Malleray set "flaps 2". During taxi to runway 32L for take-off I reacquainted myself with the A321's thrust reversers, handy for keeping a slow taxi speed in wet conditions on our light 74,400kg aircraft (18,500kg of fuel, 14 occupants and 5,000kg of flight-test kit). Once cleared by ATC for take-off, I advanced the thrust levers to the FLX/MCT detent. Power on both engines ramped up symmetrically and quickly, allowing me to keep the Neo dead on centreline. The 1,000lb of additional thrust offered by the new engines, when combined with slower rotation and lift-off speeds, required more rudder authority. To this end, Airbus increased the rudder's maximum deflection from 25° to 30°, with pedal range of motion unchanged. Once airborne the gear and flaps were retracted for transit to our working area west of Toulouse. During the climb to an intermediate altitude I hand-flew the Neo to re-familiarise myself with the FBW aircraft's handling qualities. Once in the working area I did a series of high angle-of-bank steep turns, up to the normal envelope limit of 67°. I appreciated the inherent turn co-ordination of the flight control system, as these manoeuvres were flown feet on the floor. Simply placing the primary flight display's flightpath vector on the horizon allowed me to maintain level flight, with the responsive engines manually modulated to maintain speed. Flight envelope protections are unchanged, and to many are a strength of Airbus's commercial aircraft. With normal flight-control laws, three angle-of-attack values are computed. The highest, AlphaPROT, is shown on the primary flight display at the top of yellow hash marks to the right of the speed tape. If AlphaPROT is reached, the autopilot will disconnect and speedbrakes retract, if extended. The stick stops commanding g and now commands angle-of-attack directly. Continued aft stick pressure is required to slow the aircraft further, just like a conventional flight-control system. Gerzanics (right) with Airbus test engineers Jean-Philippe Cottet and Sandra Bour-Schaeffer Max Kingsley-Jones/FlightGlobal The next slower speed is AlphaFLOOR, which is not displayed to the pilot. Before reaching AlphaFLOOR, a low-energy warning is triggered, causing an audible "SPEED, SPEED, SPEED" to be sounded. At AlphaFLOOR, the autothrust system will engage and advance both engines to the take-off/go-around (TOGA) power setting regardless of the actual thrust lever position. In no case will the aircraft slow below AlphaMAX, a speed just above the actual stall angle-of-attack which is indicated by a red band on the speed tape. Miche de Malleray next had me slow for a demonstration of these envelope protection features. The demonstrations were performed in two configurations: one clean, and the other with gear down and flaps "3". I slowed twice in each configuration. The first time, when AlphaFLOOR was reached, Miche de Malleray disconnected the autothrust, allowing me to stabilise at AlphaMAX. In both configurations the aircraft was stable as a rock at AlphaMAX, with no wing rock or meandering in side slip. Roll control was still precise, with turns at 20° angle-of-bank turns to a heading easily accomplished. Neo maintains a respectable pace at altitude, while burning less fuel than its predecessor Max Kingsley-Jones/FlightGlobal For the second deceleration in each configuration the autothrust was allowed to engage when AlphaFLOOR was reached. In both instances, TOGA power was automatically commanded and the aircraft powered out of the slow-speed state. To highlight the Neo's capabilities in an emergency situation, we simulated a close encounter with the ground. Level at FL140 while still configured with gear deployed and flaps "3", I used manual thrust to hold 150KIAS (knots, indicated airspeed) – equivalent to Vls+10 for our configuration and weight. Miche de Malleray then bellowed "Terrain!" to simulate a GP&WS warning. With my hands off the thrust levers, I rapidly pulled full aft on stick. At AlphaFLOOR the autothrust engaged and selected TOGA thrust. The aircraft reached a nose-high attitude of over 20° as the airspeed stabilised at 140kt (260km/h). We climbed away from the simulated terrain at a rate of 2,400ft/min, with no aircraft exceedances. The FBW control system made the escape manoeuvre a no-brainer, helping even the least proficient pilot avoid controlled flight into terrain. z Chunky PW1100G dominates the wing Max Kingsley-Jones/FlightGlobal For the last low-speed manoeuvre we added a lateral component to the above GP&WS escape exercise. At the same conditions as detailed above, Miche de Malleray directed me to roll the aircraft to the right to avoid rising terrain. While holding full aft pressure, I planted the stick in the aft right corner. The nose initially dropped a few degrees and the aircraft crisply rolled to 45° AoB. The nose tracked smoothly to the right as we calmly climbed away from the simulated terrain. SIMULATED ENGINE FAILURE While still configured with gear-down and flaps "3", I lowered the nose and recovered to level flight. Once in a level attitude, I advanced both thrust levers to TOGA to simulate a take-off. As has been pointed out in previous flight-test reports, a fly-by-wire Airbus's initial response to an engine failure is similar to an aircraft with conventional flight control: yawing and a wing drop. The design of the Airbus flight-control system allows for recognition of the failure, but limits the aircraft's dynamic response so that things don't quickly get out of hand. Climbing in a 12° nose-high attitude at about 145KIAS, Miche de Malleray rapidly retarded the right thrust lever to idle to simulate an engine failure. Initially I let the aircraft respond to the asymmetric thrust condition, to observe its response. As expected, the nose yawed to the right with a corresponding wing drop of about 5°. The magnitude of the drop was on par with that I had experienced when I flew the A350 several years ago. This came somewhat as a surprise, as I had expected a bigger wing drop. While developing the A320neo series, Airbus refined its flight control laws, endeavouring to make them handle more like their widebody stablemates in crosswind landings. They have a more wings-level attitude when they de-crab for touchdown. With landing flap settings (3 or 4), the A320neo's roll due to yaw (phi to beta ratio/dihedral effect) has been reduced by half compared with the A320ceo series. Once stabilised in the TOGA power engine-out climb, less than 20kg of left-pedal input was needed to center the PFD's BETA target. To optimise climb performance some side slip is allowed, with the Neo not being in full co-ordinated flight. The low pedal forces and newly reduced apparent dihedral effect combined to make the Neo's response to an engine failure a somewhat docile event. CRUISING BACK TO TOULOUSE After completing the medium-altitude evaluations, another journalist pilot climbed the aircraft to FL330 for two brief cruise-performance points. The first was at Mach 0.76, simulating a long-range cruise condition. On the ISA -2°C day the 67t Neo trued out at 501kt with a total fuel flow of only 2,200kg/h. Next, Mach 0.80 was held to simulate a high-speed cruise condition. Fuel flow increased to 2,440kg/h as the Neo trued out at 527kt. While by no means definitive, these snapshot figures show the Neo can maintain a respectable pace at altitude while gulping less fuel than its predecessor. Midway through the descent back to Toulouse, I sampled how the A321neo handled in the traffic pattern. ATC provided radar vectors for an ILS approach to runway 32L. I hand-flew the approach to 200ft above ground level (AGL), where Miche de Malleray levelled the aircraft off to demonstrate the airborne part of the optional runway-end overrun warning/runway-overrun prevention system (ROW/ROPS). ROW is active at 500ft AGL and aims to prevent long landings and subsequent runway departures by alerting the crew to the necessity of a go-around. Configured for landing, Miche de Malleray flew the A321neo at 140KIAS down the runway. The ROW uses real-time position and energy data (speed and altitude) to determine if a landing can be made in the available runway remaining. About a third of the way down 32L, the message "IF WET: RWY TOO SHORT" appeared on the primary flight display. A little further down the runway a repetitive aural, "RWY TOO SHORT", was sounded with the terse "RWY TOO SHORT" message displayed. At the end of the runway, the gear was retracted and Miche de Malleray started a climbing right turn to the crosswind pattern leg. On downwind, I took control for a hand-flown visual approach to 32R with a sidestep to the land on 32L at 1,000ft AGL. The initial plan was modified when low clouds forced us to fly the ILS final segment to 32L. With the gear down and flaps "4", I manually held an approach speed of 129KIAS. We broke out at 1,600ft AGL and visually acquired both 32L and 32R. I hastily aligned with 32R, about 200m to the southeast. I was well stabilised at 1,000ft AGL when Miche de Malleray directed a sidestep to 32L for our full-stop landing. Stabilised on the ILS, Gerzanics flies the A321neo towards Toulouse's runway 32L Max Kingsley-Jones/FlightGlobal Whilst still in a 3° descent, I crisply rolled the aircraft to the left in a 25° bank to align with the left runway. At 500ft AGL, I was aligned with 32L as judged by the localiser and on the ILS glidepath. At 20ft radio-altimeter (RA) I started the round-out portion of the flare manoeuvre, retarding the thrust levers to idle at 10ft RA. After a smooth touchdown, the aircraft was initially slowed by thrust reversers alone, light wheel-braking applied for runway turn-off at taxiway S10. Once clear of the runway I taxied to the hold point for RWY32L. When Airbus offered FlightGlobal the chance to fly the A321neo, my first thought was: how could an engine swap on a proven airframe be that big a deal? Compared with the current engine option, the A321neo can carry the same passenger load, out of the same or shorter runways, 490nm (900km) farther. That's London to Berlin as the crow flies – a big deal indeed. While both CFM and P&W are to be applauded for bringing dramatically more fuel efficient engines to the table, the success of the A321neo will not be a reflection of their efforts alone. Airbus engineers and flight-test personnel played critical roles in tweaking the A321's aerodynamics and flight controls to put these fuel-sipping engines to good use. With the A321neo I can wholeheartedly agree with the marketing hyperbole. It really is new and improved. Link to comment Share on other sites More sharing options...
Seeker Posted May 26, 2017 Share Posted May 26, 2017 Nice, looks like a good aircraft, too bad we won't be seeing any of them in Canada. Meanwhile, over at Boeing, here's a video of the cockpit procedures on the brand new 737 Max: https://www.youtube.com/watch?v=r0wptjX3aO0 Link to comment Share on other sites More sharing options...
rudder Posted May 26, 2017 Share Posted May 26, 2017 2 hours ago, seeker said: Nice, looks like a good aircraft, too bad we won't be seeing any of them in Canada. Meanwhile, over at Boeing, here's a video of the cockpit procedures on the brand new 737 Max: https://www.youtube.com/watch?v=r0wptjX3aO0 The cockpit noise level is about right...... Link to comment Share on other sites More sharing options...
Super 80 Posted May 28, 2017 Share Posted May 28, 2017 On 2017-05-26 at 7:18 AM, seeker said: Nice, looks like a good aircraft, too bad we won't be seeing any of them in Canada. Airbus is pretty strident about Air Canada taking the A321neo. Link to comment Share on other sites More sharing options...
Seeker Posted May 28, 2017 Share Posted May 28, 2017 5 hours ago, Super 80 said: Airbus is pretty strident about Air Canada taking the A321neo. The 737 sim is already installed and guys are bidding the positions. I guess it's not impossible that an A321Neo might still show up but the odds are low. Link to comment Share on other sites More sharing options...
Super 80 Posted May 28, 2017 Share Posted May 28, 2017 It isn't an either-or, Air Canada took delivery of a brand new A321 for Rouge just about a year ago. Link to comment Share on other sites More sharing options...
rudder Posted May 28, 2017 Share Posted May 28, 2017 Rouge would be well suited to go all Airbus. A mix of 320/321/330 would create significant efficiencies. Mainline will eventually be all Boeing (other than c-series). Link to comment Share on other sites More sharing options...
Super 80 Posted May 28, 2017 Share Posted May 28, 2017 I think you can probably extrapolate something of a plan from the fact that Rouge received five brand new A321s while mainline received another five ex-Air France A321s that are already ten to fifteen years old. I haven't seen any dispatch materials for the Max, but I have to imagine the Max 9 will struggle operating in a Slaveship configuration into shorter Caribbean runways. Link to comment Share on other sites More sharing options...
Seeker Posted May 29, 2017 Share Posted May 29, 2017 7 minutes ago, Rich Pulman said: The funny thing is that Air Canada could have had a 'B' scale operation with a mix of 319/320/330s back in 2001, but ACPA convinced their membership that the world would come to an end should that ever come to fruition. How times have changed! We haven't seen the end of the story yet - some believe the world is coming to an end! Link to comment Share on other sites More sharing options...
rudder Posted May 29, 2017 Share Posted May 29, 2017 16 hours ago, Rich Pulman said: The funny thing is that Air Canada could have had a 'B' scale operation with a mix of 319/320/330s back in 2001, but ACPA convinced their membership that the world would come to an end should that ever come to fruition. How times have changed! No more B scale. ACPA should not approve any Rouge fleet expansion unless pay scales are harmonized. The reality is that most Rouge flying used to be mainline flying. Unit cost savings can come from hundreds of new-hire FA's and seat configuration densification. Pilot pay should be removed as a tool for cost reductions. Link to comment Share on other sites More sharing options...
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