Analysis: Airbus Corporate Jet
Transcription
Analysis: Airbus Corporate Jet
Analysis Airbus Corporate Jet Boasting the largest cabin cross section and some of the most advanced systems among its peers, Airbus’ airliner in pinstripes is ready to compete. By Fred George Photography by Mike Vines wo decades ago, Airbus revolutionized airliner design by introducing the then-radical A320. It had a wider cabin compared to conventional singleaisle aircraft. It was fitted with a new-gener at ion su per-critical wing for higher cruise speed and better fuel economy. It was en d owed with the most-ad v an c e d glass cockpit of any airliner yet produced. And it was the first subsonic aircraft to be equipped with fly-by-wire flight controls and a side-stick controller. W h ile not an instant success, the pio- T 44 Business &CommercialAviation ■ July 2002 neering A320 eventually captured a signific ant share of the market for the Fren c h , German, Spanish and U.K. partners. Airbus evolved shorter and longer, A318, A319 and A 321, variants of the basic A320 design. Moreover, the A320 series helped spawn the A330, A340 and A380 families of Airbus aircraft that, Airbus boasts, together with the A320 family, now account for more than half of new airliner sales in the world. Five years ago, buoyed by the success of the A319 airliner, Airbus decided to lock horns with Boeing, as well as Bombardier and Gulfstream in the ultra-long - r ang e business aircraft market by announcing the A319CJ, or Airbus Corporate Jetliner. Based upon the A319, the 22-foot-shorter variant of the A320, Airbus figured the ACJ’s bigger cabin cross-section and advanced technology were viewed as competitive advantages in the business aircraft market, just as they were in the airline market. Moreover, the ACJ could be fitted with up to six auxiliary center tanks (ACTs) in t he fuselage, boosting its range to more than 6,000 miles, an increase of up to 2,200 miles over the standard A319 aircraft. The A319CJ, built at the con s o rt i u m ’s plant in Hamburg, Germany, would be the “crème de la crème” of the A320 famil y, according to Richard Gaona, vice president of the consortium’s ACJ division. Tanked and trimmed according to individual cust om er needs, it could be configured as a head-of-state or government transport, an executive jet, or a corporate shuttle aircraft, among other variations. ACJ certification occurred in mid-1999. However, Airbus could allocate only four ACJ delivery slots per year because of high www.AviationNow.com/BCA d e m and for its A319 and A321 jet l i ner s . This threw cold wat er on hot cus t om er demand, Gaona conceded. Nobody wants to wait four or five years for delivery. Just as importantly, Boeing, Bombardier and Gulfstream had a healthy head start in the ultra-long-range market segment and they had all the best customer contacts in corporate America and the international business aviation community. And all three branched out into fractional ownership programs. Airbus was a newcomer to business aviation. Newer still to fractional ownership, in 2001 it inked a deal with ill-fated UAL subsidiary Avolar. Un d a u nted, Gaona and his ACJ team have now refocused on the business aircraft market, eager to steal half of future orders from archrival Boeing Business Jets. Can they do it? This report may provide some answers. Aircraft Structure and Systems The original A320 earned type certification in 1988. In January 1989, the FAA imposed several special conditions relating to the aircraft’s unique fly-by-wire control system, engine controls, side-stick controllers and flight characteristics. Heavy re l i ance on computers also necessitated special conditions regarding resistance to high-intensity radiated fields and lightning strikes. The A319 variant was awarded type certification in 1996, including voluntary compliance with newer requirements, such as more-stringent structure, flight loads and m ane u v ers, gust lo ads and mane u v er i ng rules specified in later certification regulat ions. The A319 C J - 133 is fitted with 26,500-lbf IAE V2527M-A5 turbofans, and t he -115 has 27,000-lbf CFM56 - 5 B 7 / P engines. The -133 was certified in accordance with JAR 25 in August 1999, according to Airbus officials. Reciprocal FAR Part 25 certification has not yet been sought. T he pr i m a ry ai rframe is made from high-strength aluminum alloy using conventional construction methods. Secondary s t ru c t ures, including the ho r i z ontal tail , vertical fin and certain flight control surfaces, are fabricated from composites. Most Airbus 320 family members have a 39,100foot cert i f ied ceil i ng and a design life g re at er than 75,000 cycles. The ACJ, in contrast, is certified to cruise at FL 410 and has a slightly higher pressurization ratio of 8.33 psi. It also has extra reinforcement in the fuselage to handle the additional weight of the auxiliary center fuel tanks. As a result, the ACJ has a design life of 18,000 flights, according to Airbus officials. The A319 airliner, in contrast, has a 48,000-flight design life. Competitors’ design lives range from 16,000 to 75,000 cycles. Airbus officials hasten to add that the ACJ is intended to fly www.AviationNow.com/BCA 4.3-hour cycles, thereby providing a design life of 77,400 hours — significantly longer than most competitors. Standard equipment now includes a dualhandrail, folding, electrically operated, illuminated airstair. The aircraft has four 73by-32-inch, Type I, plug-design doors, two f o rw a rd and two aft, plus left and right, 40.1-by-20-inch, inward-opening, Type III over-wing emergency exits. The forward and aft cargo bays are accessible through a pair of hydraulically actuated, 48.3-by-71.5-inch doors. The outward opening door design allows forward or aft ACTs to be removed and replaced without removing the associated cargo door. A hand pump can be used to open the doors with no power on the aircraft. Need to replace any door? Each is an i nt erc h ang e ab le part. No hand fitting is necessary. Fuel is contained in wing and center fuel tanks with a capacity of 42,223 pounds. The standard four ACTs, one forward and three aft, hold 18, 787 pounds, for a total fuel c a p a c i ty of 61,010 pounds, enough for a maximum range of about 4, 800 mile s , a c c o rd i ng to oper ators. The four tank s leave 124 cubic feet of baggage space in the c a rgo hold. The optional fifth and sixth ACT boost fuel capacity to 71,815 pounds, stretching maximum range to 6,000-plus miles, but they eliminate all under- f lo o r cargo volume. A i r b us is evaluat i ng a ne w, four- A C T configuration, with 1,500 pounds more fuel capacity and 255 cubic feet of baggage volume in the aft cargo bay. The extra fuel also should boost range by 150 miles. Fuel is transferred from the ACTs to the center fuel tank using cabin air pressure. Six dry-canister AC pumps supply the engines Standard equipment now includes a lighted airs t a i r, a vi r tu al ne ce ss i ty c on si d er i n g t h e A319CJ’s tall stance and intended use as a business aircraft. and APU. A static inverter, powered by the aircraft batteries, furnishes AC power for a fuel pump during APU start. The primary electrical system is 115 VAC, 400 Hz, with a 28 VDC used for secondary systems. Both use a split bus architecture with automatic bus tie and load shedding. Each engine is fitted with a 90 Kva, brushless AC IDG, supplemented by a 90 Kva constant-speed AC generator powered by the APU. Transformer rectifiers supply DC. If both engines and the APU fail in flight, a ram air turbine (RAT), powering the blue c h annel of the hydraulic system, can be deployed. This, in turn, furnishes power to a The super-critical airfoil, illustrated by the characteristic bottom surface reflex “s” curve, enables the A319CJ to cruise at 0.78 Mach with 99-plus-percent fuel efficiency at all but the lightest weights. Business &CommercialAviation ■ July 2002 45 Analysis fourth, hydraulically powered, emergency AC generator. Twin 23 AH batteries supply DC power to start the APU and furnish emergency DC and AC power by means of a static inverter. Airbus Corporate Jet Price Green Aircraft . . . . . . . . . . . $39,000,000 Estimated Completion Cost . $12,000,000 Total . . . . . . . . . . . . . . . . . $51,000,000 Characteristics Wing Loading . . . . . . . . . . . . . . . . 126.3 Power Loading . . . . . . . . . . . . . . . . . 3.14 Noise (EPNdB) est’d. . . . 85.9/92.0/93.9 Seating . . . . . . . . . . . . . . . . . . 4+12/48 Dimensions (ft/m) External Length . . . . . . . . . . . . . . . . . 111.0/33.8 Height . . . . . . . . . . . . . . . . . . 38.6/11.8 Span . . . . . . . . . . . . . . . . . . 111.8/34.1 Internal Length . . . . . . . . . . . . . . . . . . 78.0/23.8 Height . . . . . . . . . . . . . . . . . . . . 7.4/2.3 Width. . . . . . . . . . . . . . . . . . . . 12.2/3.7 Thrust Engine. . . . . . . . . . . . . 2 IAE V2527M-A5 Output/ Flat Rating OAT°C . . 26,500/ISA+30°C Inspection Interval . . . . . . . . . . . . . . . OC Weights (lb/kg) Max Ramp . . . . . . . . . . 167,380/75,922 Max Takeoff . . . . . . . . . 166,445/75,498 Max Landing . . . . . . . . 137,800/62,505 Zero Fuel . . . . . . . . . . 128,970/58,500c BOW . . . . . . . . . . . . . . . 94,245/42,749 Max Payload. . . . . . . . . . 34,725/15,751 Useful Load . . . . . . . . . . 73,135/33,174 Executive Payload . . . . . . . . 2,400/1,089 Max Fuel . . . . . . . . . . . . 61,016/27,676 Payload with Max Fuel. . . . 12,119/5,497 Fuel with Max Payload. . . 38,410/17,423 Fuel with Executive Payload . . . . 61,016/27,676 Limits Mmo . . . . . . . . . . . . . . . . . . . . . . 0.820 FL/Vmo . . . . . . . . . . . . . . . . FL 250/350 PSI. . . . . . . . . . . . . . . . . . . . . . . . . . 8.3 Climb Time to FL 370 . . . . . . . . . . . . . . 23 min. FAR Part 25 OEI rate (fpm) . . . . . . . . . na FAR Part 25 OEI gradient (ft/nm) . . . . . na Ceilings (ft/m) Certificated . . . . . . . . . . 41,000/12,497 All-Engine Service. . . . . . 37,000/11,278 Engine-Out Service . . . . . . 22,000/6,706 Sea Level Cabin . . . . . . . . 22,000/6,706 Certification . . . . . . . . . . . . . . JAR Part 25 46 Business &CommercialAviation ■ July 2002 ACJ has a triple - c h annel, 3,000 - p s i hydraulic system powering the landing gear, spoilers, wheel brakes, flight controls, nosewheel steering, thrust reversers and cargo doors. The triple - c h annel design, along with engine-driven and electrically powered pumps, a left/right power transfer unit and the RAT, assure maximum redundancy. Each of the flight controls has multiple actuators powered by different combinations of channels. This reduces the probability of control loss to less than one in a billion if single- or double-component failure occurs. Fully powered, irreversible primary and secondary flight controls are fly-by-wire (FBW) controlled. Artificial feel is provided by springs in the side-stick control units. A i r b us says FBW saves se v eral hundre d pounds of weight. The landing gear feature carbon/carbon brakes with an estimated life of 1,500 to 2, 200 lan d i ngs and an overhaul cost of $50,000, according to Airbus. Bleed air from the APU or from engines on the ground or in flight supplies the twopack air-conditioning system. The ACJ uses partial recirculation, with three-zone temperature control. Maximum pressurization is 8.3 psi, pro v id i ng an 8,000-foot cab i n altitude at FL 410. Anti-ice protection for the engine inlets and wing leading edges, including a crossflow feature, also is provided by bleed air. T he windshields and vario us probes are electrically heated for anti-ice protection. Emergency oxygen for the pilots is furni s hed by a 77-cubic-foot bottle. Cab i n crew and passenger emergency oxygen systems are installed by the customer during completion. An APIC APS 3200 APU, rated for engine starts up to 9,200 feet field elevation and ISA + 35°C temper at ures, is stan d a rd equipment. A Honeywell GTCP 36-300A is a factory standard option. Also available is the new Honeywell 131-9A APU, with 12percent more power, yielding faster cabin cool-down times, quicker engine starts, better high-altitude electrical power output in flight and lower hourly operating cost. Cabin, Range and Weight Allowances The green weight of a -133 aircraft is 82,507 pounds, while -115 ai rcraft weigh 200 pounds less. Sogerma in To u lo use; Jet Av i at ion in Basel; Lufthansa Tec h nik in Ha m b urg; Ozark Aircraft Systems in B ent on v il le, Ark.; and As s o c i ated Air Center in Dallas are among the authorized Airbus Corporate Jet completion centers. T he com p let ion weight allow an c e d e pends upon the number of ACTs installed in the aircraft. With full fuel in the standard four-tank package, for example, c om p let ions as heavy as 20,000 pounds, accommodating up to 12 passengers, are feasible. The optional fifth and sixth tanks add 1,380 pounds to the green weight. This reduces the tanks-full completion allowance to just over 11,000 pounds, assu m i ng an eight-passenger payload. Most customers favor the four-tank configuration because they prefer its range/payload tradeoff. Completion centers told B/CA that the ACJ’s factory-designed ACTs are easier to remove, replace and re-rig than some after-market aux tank systems in other large-cabin aircraft. The ACJ has removable panels in the cabin floor for maintenance access to the ACT plumbing and gauging systems. Com p let ion cent ers said su c h access panels don’t limit the interior configuration any more than in other aircraft. They also advise customers to order the optional Cabin Intercommunication Data System (CIDS), a digital interface unit that enables various cabin systems, such as light- www.AviationNow.com/BCA Aero Services’ ACJ, completed by SOGERMA, has four seating areas in the main cabin. Extensive use of off-the-shelf airliner hardware expedited certification and helped keep completion weight down. ing, inflight entertainment and air conditioning, to interface with main aircraft systems. They praised the ACJ’s three-zone temperature control because it simplifies airflow distribution from front to rear. Choice of completion materials, such as fabrics, upholstery and furniture coverings, may be limited to those approved for commercial airliners with seating capacities in excess of 20 passeng ers, unless a blanket exemption is sought through the controll i ng ai rw o rt h i ness autho r i ty. In No rt h America, for example, Airbus has not pursued such an exemption through Transport Canada or the FAA, as has Boeing, completion centers told B/CA. At present, North A m er i c an com p let ion cent ers are taske d with this responsibility, adding to completion cost and time. The only four interiors we’ve seen thus far are relatively high-density corporate shuttle or group charter configurations. The Aero Services group charter aircraft that we flew for this report, for example, is equipped with five ACTs and 29 passeng er se at s . Completed by Sogerma, it has a forward VIP section, including a lavatory with shower, plus four, two-by-four super club-class seating areas in the main cabin. Sogerma used plenty of off-the-shelf airliner interior c om p onents, including sidewall pane l s , overhead bins and PSUs, to keep the weight down and to speed the completion process. Flying Impressions What’s it like to fly? The ACJ has the most comfortable cockpit we’ve yet experienced, immediately apparent when we strapped i nto the left se at of Aero Services’ ACJ, a c c om p anied by Pet er Chan d ler, Airbus experimental test pilot in the right seat and www.AviationNow.com/BCA Aero Services’ chief pilot Richard Cimino on the jump seat as safety pilot. The ACJ’s side-stick controller, which eliminates the column and yoke between the pilots’ knees, is the main reason why cockpit comfort is head-and-shoulders above the competition. For all its advanced fly-by-wire, throttleby-wire, steer-by-wire and brake-by-wire controls, the A319CJ flies like a typically refined French airplane, albeit one with a very bright digital flight engineer on board who majored in cockpit ergonomics. Quite cle a r l y, the FBW flight cont ro l system is the most critical of the four digital c ont rol systems. Two pr i m a ry and thre e secondary, dual-channel flight control computers, each using dissimilar hardware and software, ensures optimum redundancy. L o se one com p u t er channel? You can still dispatch and have critical level redundancy, as well as full functionality. The five c om p u t ers pro v ide FBW cont rol of the elevators, ailerons and spoilers, along with horizontal stabilizer trim. Rudder control, though, is conventional, augmented by a computerized yaw damper. There are no mechanical links between t he side stick and the flight cont ro l s . Instead, the FBW system uses computer control laws to determine how much control surface deflection is needed to achieve the desired result. Control laws, in essence, are the software "brains" of a fly-by-wire system, that process pilot, IRS, air data and other sensor signals to generate the appropriate electrical commands to the aircraft's hydraulic control surface actuators. FBW enables aircraft designers to overcome the classic stability versus maneuverab il i ty aerodynamic design compromise. A i rcraft with con v ent ional, mec h ani c a l link flight controls can be designed to be as stable as ocean liners or have dogfight agility — but not both. The FBW system's control laws, though, enable aircraft designers to endow the aircraft with both exceptional stab il i ty an d maneuverability. Stability characteristics are enhanced by moving the control surfaces as nec e s s a ry, without any inputs from the pilot, to hold pitch and roll attitude, within s pec i f ied pitch, roll, speed, g-lo ad an d angle-of-attack protection limits, similar to t he touch-cont rol steer i ng mode of an autopilot. Don't touch the side stick, and the aircraft remains fixed in attitude. M ane u v er ab il i ty characteristics are enhanced by deflecting the control surfaces as needed, in response to pilot inputs, to achieve maximum aerodynamic perform- The right side of the aircraft has four club seat sections, each with four chairs and a folding work table. Business &CommercialAviation ■ July 2002 47 Analysis Airbus Corporate Jet These three graphs are designed to be used together to provide a broad overview of the ACJ’s approximate performance.They were pieced together using several data sources, so it is especially critical that they not be used for fine-tuned comparisons, let alone flight planning. For a complete operational analysis, use realistic completion weights for the candidate aircraft, look closely at the JAR 25 Approved Flight Manual, and be sure to use Airbus’ Less Paper in the Cockpit (LPC) mission-planning software. Notably, we had no access to these essential tools when we prepared this report. Time and Fuel vs. Distance — This graph shows the range performance of A319CJ at 0.78 Mach high-speed cruise, assuming departure at MTOW, the standard four ACT configuration and a 4,600-pound NBAA IFR reserve.We chose not to include a long-range cruise line because the ACJ’s advanced super-critical wing enables it to cruise at this speed with 99 percent, or better, specific range efficiency. Notably, the ACJ’s relatively high wing loading and airfoil design result in comparatively low initial cruise altitudes at the highest weights. Using this speed profile, for example, leveling off at FL 350 as the initial cruise altitude yields the best specific range performance,assuming a departure at MTOW. After five to six hours, a step climb to FL 370 improves specific range performance. The ACJ should be flown at FL 410 only at relatively light weights. However, the highest altitude for which we had cruise performance data was FL 390. Specific Range — The ratio of true airspeed to hourly fuel burn is a measure of fuel efficiency. Using a mid-range cruise weight of 130,000 pounds, the chart illustrates that it is counterproductive to push the ACJ to a higher than recommended cruise altitude when cruising at 0.78 Mach, equivalent to 447 KTAS in ISA conditions. The specific range, at this mid-range cruise weight, actually is slightly better at FL 370 than FL 390, even though the aircraft has ample reserve climb thrust to climb to FL 390 or FL 410. Range/P ayload Profile — The purpose of this graph is to provide gross simulations of various trips under a variety of payload and airport density altitude conditions, with the goal of flying the longest distance at 0.78 Mach high-speed cruise.The four payload lines are highly simplistic, based upon Airbus data at minimum weights and B/CA estimates at maximum weights, with straight lines between the endpoints.We estimated the range performance assuming departure at MTOW, with maximum fuel and available payload, using the flight-planning guide for a standard A319 airliner. Boiled down to basics, the ACJ has 10.5 to 11.0 hours of endurance with the standard four ACTs, a typical 15,000- to 18,000-pound ultra-large cabin interior and 20 passengers on board. That’s enough for a maximum range of about 5,000 miles, based upon our estimates.Range with a super-lean, 8,000-pound interior and eight passengers is 5,400-plus miles, according to Airbus officials. 48 Business &CommercialAviation ■ July 2002 www.AviationNow.com/BCA ance within said protection limits. T h ree levels of FBW cont rol law are available, assuring optimum redundancy. "Normal" control law, the top-level mode, is available when all systems are working or after a single computer or related system failure. While in flight, fore/aft movement of the side-stick controller changes g-loading in pitch and lateral movement controls roll rate, within said protection limits. Pitch trim is automatic, adjusting for speed and c on f i g ur at ion changes. The system also compensates for variations in pitch-control re s p on se associated with c.g. movement. Normal control law incorporates ground, flight and landing flare sub-modes. The transition between the three sub-modes is automatic and virtually transparent to the crew, tossing in just enough digital magic to impart a natural control feel and appropriate cont rol re s p on se dur i ng the critical takeoff and landing phases of flight. Ground law mode enables the crew to have full control over the flight control surfaces. At liftoff, the system blends in flight law mode, with its envelope and attitude pro t ec t ions. The process is re v er sed for landing, except that at 50 feet the system slowly rolls in two degrees of nose-down pitch trim for a more natural pitch feel during landing flare. The FBW system is so robust that the reversion modes aren’t taught during initial or recurrent flight training, unless the operator requests otherwise. All maneuvers are performed using normal control law. Actual c ont rol law re v er s ion events have been “very, very, very few,” according to Airbus o fficials. Actual MTBF statistics for the FBW system were not avail ab le from Airbus. One of the biggest advantages of FBW is the ability of any pilot, regardless of experience level, to extract maximum performance from the airplane at critical times. If wind shear is encountered, for example, the procedure is simple. Reef all the way back on the side-stick and slam the throttles to the forward stop. Immediately, the aircraft rotates to the optimum angle-of-attack for climb, within g limits, and the eng i ne s spool up to maximum thrust. The escape maneuver is perfectly and consistently executed, regardless of the amount of gray hair or accumulated flight hours in the cockpit. A word of caution app l ies here. The FBW system won’t let you pull over 2.5 g’s during an escape maneuver. The pilot isn’t given the option of overstressing the aircraft if it’s necessary to avoid hitting the ground. T he ai rcraft also has one of the most capable avionics suites ever installed in a civil aircraft (see accompanying sidebar). Airbus’ design philosophy was years ahead www.AviationNow.com/BCA of most business aircraft when introduced two dec ades ago. Pilots of lat e - m o d e l heavy-iron business aircraft, though, should have little tro u b le ad a p t i ng to Airbus ’ a u t om at ion, even though the acron y m s , systems design feat ures and some colo r c on v ent ions are diff erent from tho se on most bus i ness ai rcraft. For all its digital c a p ab il i t ies, the ACJ still is an ai r p l ane designed by and for pilots. Airbus pilots we’ve contacted love the airplane and would loathe going back to a conventional aircraft. Most engine and systems functions are automated, thereby reducing pilot workload. Engine start, for example, is handled by computers. APU bleed is automatically rerouted from packs to starter, the FADEC h an d les the eng i ne start, the gener at o r comes on line, and the APU bleed air then is rerouted to the packs. I t ’s easy to get used to flying with the side-stick controller and using FBW normal control, based on our observations. But what The side-stick controller provides excellent artificial control feel. After 15 minutes, we felt comfortable using it in place of a yoke. ACJ Avionics The ACJ has one of the most capable avionics suites ever installed in a civil aircraft. Six large-format CRTs provide a wealth of information, including context-sensitive system synoptics, extensive use of graphics and text prompts to keep the crew out of trouble after coping with an abnormality or emergency. Color cues, boxed text titles and flashing annunciations provided by the system ensure that the pilots are “in the loop” in spite of the aircraft’s advanced automation. Hand-eye coordination features are especially well designed, in our opinion. However, it takes a little time to get used to the non-moving autothrottles. Normally, the pilot flying engages the system by pushing the throttles up to the flex takeoff/max continuous thrust detent in the quadrant. At 3,500 feet, or a manually selected, noise abatement power reduction altitude, the pilot pulls the throttles back to the climb detent. That’s the last time the throttles move, or have to be touched, until retarding to idle during landing flare. All thrust changes are controlled by the autothrottle system using automatic or manual speed set modes. The avionics package includes triple ADIRS integrated with angle-of-attack sensors, dual multi-mode nav radios with ILS and GPS receivers, dual VOR receivers, dual DMEs, dual Mode S transponders, and two radio altimeters, plus a Doppler weather radar, ADF,TCAS and EGPWS. Triple VHF voice/data radios, triple audio panels and dual radio management units, plus a single HF, SELCAL, solid-state CVR and ACARS with printer also are included. There are provisions for a multi-channel satcom system. A HUD option is under development and is slated for JAA and FAA certification in December 2004. EVS sensor development will be discussed at an upcoming customer focus group meeting. Business &CommercialAviation ■ July 2002 49 Analysis if highly improbable failures were to cause loss of normal control law? If two failures occur within a system, such as loss of two of the aircraft’s three hydraulic systems or loss of both pitch trim channels, then the system reverts to “alternate” control law. This second-tier mode provides “normal” law handling characteristics with reduced envelope and attitude limit protection. In the event of triple failures, the system reverts to “direct” law. The pilot then has direct control of the control surfaces, with elevator deflection compensated for aircraft c.g. Even though it’s highly unlikely that a pilot would ever encounter such reversions, we wanted to experience “alternate” and “direct” control law. So Chandler turned off both flight control computers. We found that it’s not hard to fly the aircraft using alternate law mode, with its normal control law feel. In the direct mode, we found flying characteristics acceptable, albeit with thrust and configuration induced pitch trim changes, similar to a conventional aircraft. The ACJ still is a stable aircraft without all its FBW capab il i t ies, but it takes som e practice to be smooth without high-level help from the computers. Stalls are impossible in flight because of the envelope protection provided by normal control law. They’re also tough on the airframe, considering the buffeting of the engine pylons and empennage. As a result, we executed them in the simulator using the control law reversion modes. The ACJ, we soon discovered, still has conventional handling qualities. There’s plenty of pre-stallwarning buffet. If stall recovery is initiated at the onset of buffet, the ACJ recovers with no loss of aplomb. When pressed close to the aerodynamic stall, however, the nose pitches up, unless the stick force is relaxed. Pull all the way into the stall and a wing often drops. S w i t c h i ng back on both flight control computers, we returned for pattern work. We found the aircraft docile during twoeng i ne oper at ions. It’s som e w h at more challenging with one engine inoperative, as we experienced in the simulator session. Why? While the flight control computers h an d le the ele v ators and wing - m o u nt e d flight controls, it’s entirely up to the pilot to step on the rudder to prevent adverse yaw. It’s back to basics during OEI takeoffs. Push the on-side rudder close to the floor and pull back to 12-degree nose-up pitch to hold V2. The maneuver takes a little practice for new pilots because the combination of body movements is different without the yoke. After a few attempts, we found the ACJ is no harder to handle than a conventional jet with wing-mounted engines during OEI takeoffs. Once at a safe altitude, we accelerated and retracted the flaps. The flight manual then calls for engagement of the autopilot and autothrottle. This allows both pilots to concentrate on coping with the emergency. The ECAM, Airbus’ term for EICAS, displays provide context-sensitive systems graphics, along with QRH recommendations handling the emergency, including balancing the fuel load and returning for landing. Conclusion? After experiencing the handling ease and capabilities of Airbus’ FBW flight controls, it’s hard to go back to 90year-old analog technology. Will Europe’s Best Triumph? A gre at ai r p l ane doesn’t autom at i c a l l y translate into great air transportation. To date, there only are 11 ACJs in service and one A319 jet l i ner con f i g ured as an ACJ. Most are in service in veteran flight departm ents with years of ai r l i ner operation s experience. These folks know how to deal with large jetliner manufacturing organiza- The standard four-ACT configuration provides 124 cubic feet of underfloor cargo volume. Bring a tall ladder for loading. tions and how to arrange for support with local com m ercial ai r l i ne mai nt enan c e departments. In the past, Airbus seemed detached from t he bus i ness aviat ion com m u ni ty, som e o per ators and com p let ion cent ers told B/CA. Five years ago, the ACJ team had few key people with any business aircraft e x per ience. Some of their marketers seemed more bent on bad-mouthing the competition than on explaining the virtues of the ACJ. More o v er, coord i nat ion between the ACJ team and Airbus headquarters seemed lacking, even though both organi z at ions were, and are, in the same office building in Toulouse. And in addition to airliners, Airbus is a world leader in production of aviation-grade red tape, according to some industry observers. All those perceptions are history, Gaona says. Of key importance was the appoint- IAE V2500 or CFMI CFM56-5? ACJ customers have a choice of engines. Thus far, all have chosen the IAE V2527M-A5 over the CFM56-5B7/P. Airbus officials claim the V2527, while adding 100 pounds per side to aircraft weight, offers slightly better fuel economy and lower FAR Part 36/ICAO Annex 16 noise levels. While both engines offer airlinerquality reliability, the IAE engine, on average, visits the shop more than seven times per 100,000 flight hours, while the CFM makes fewer than five visits per 100,000 flight hours, according to Airbus’ data for the last 12 months. Hidden behind this cover is a quiet, fuel-efficient IAE V2527M-A5, standard aboard the A319CJ. XX Business &CommercialAviation ■ July 2002 www.AviationNow.com/BCA Analysis Stout carbon/carbon brakes provide excellent stopping power without grabbing when cold. Airbus Corporate Jet Comparison Profile (Percent Relative to Average) Tradeoffs are a reality of aircraft design, although engineers attempt to optimize the blend of capabilities, performance and passenger comfort. In order to portray graphically the strengths and compromises of specific aircraft, B/CA compares the subject aircraft to the composite characteristics of other aircraft in its class, computing the percentage differences for the various parameters. We also include the absolute value of each parameter, along with the relative ranking, for the subject aircraft in the composite group. For this Comparison Profile, B/CA includes the Airbus A319CJ Corporate Jetliner, Boeing Business Jet BBJ1, Bombardier Global Express and Gulfstream VSP. The Comparison Profile quite clearly illustrates that the ACJ has the biggest cabin and the highest maximum payload of any aircraft in the composite group.Surprisingly, it also offers the second-best hot-and-high airport takeoff performance. Cruise performance, though, is airliner grade, a notch below that of traditional business aircraft. When the ACJ’s $51 million price is considered, its strongest asset is its lowest cost per cubic foot of cabin volume. 52 Business &CommercialAviation ■ July 2002 ment of Haig Hagopian, a well-known, 30plus-year business aviation veteran, to take on a high-profile role in ACJ marketing in No rth America. Ha g o pi an is wid e l y respected for his willingness to listen to customers and respond to their concerns. With m o re members like that, the ACJ team could overc ome market inertia. To cut delivery lead time for new orders, ACJ production rates will increase to six deliveries in 2003. Gaona would like to see the rate increased in 2004, if demand warrants. To improve after-sale communications, Gaona now meets with each one of his ACJ operators at least twice per year. He can be reached 24/7 on his mobile phone at other times. He’s also assigned no more than three customers to each technical service representative in Toulouse, using the adjac ency of the ACJ division and the hom e office to best advantage. Warranty administration continues to be handled by UAL’s United Services during the five-year airframe, engine and avionics warranty period. United Services also offers long-term ACJ support, regarded by Gaona as the best in the airline industry. The ACJ has been relatively trouble-free, and operators said that spares support from Airbus and its vendors has been satisfactory. Most of the engine and systems gremlins were wrung out by dozens of airlines in regular passenger service. De s pite having a high deg ree of commonality with garden-variety airliners, both the ACJ and BBJ are distinct models not routinely operated by commercial air carriers. Thus, the ACJ’s 18,000-flight design life is not a limitation in the business aircraft resale market, but it’s a shortcoming t h at could se v erely limit its value in the commercial airliner resale market, considering the 3,000-cycle-per-year work schedule of the average single-aisle jetliner. A n o t her dark cloud lo oms large. The demand for $50-million-plus, airliner-size b us i ness aircraft seems to have reached a plateau, as illustrated by the soft sales both of new aircraft and of fractional ownership u nits dur i ng the past 12 months. Even demand for traditional, ultra-long-range b us i ness aircraft, such as the Gulfstream V/VSP and Global Express, has slowed as a result of the world economic slump. Yet, Gaona, Hagopian and the rest of the ACJ team are confident the slump in ACJ sales is over. They maintain that the ACJ can triumph because it has the biggest cabin cross-section, the most-modern systems, and a strong swell of acceptance in the airline community. Clearly, when the world economy does rebound, the ACJ team will be better positioned than in the past to skim la crème from the very top of the business aircraft market. B/CA www.AviationNow.com/BCA