The super-midsize class has been one of the hottest selling segments of business aircraft in recent years. These versatile aircraft can fly eight passengers nonstop between East Coast and West Coast North American cities at true jetliner speeds. They also can fly nonstop across the North Atlantic eastbound. Almost all can fly westbound from England or Ireland to the U.S. East Coast. To fly from virtually any city in Europe to any destination in North America, they need no more than one refueling stop. Their cabins provide passengers with ample room to work, to relax and to converse. They have full galley facilities, ample storage space for carry-on luggage and full-width aft lavatories. Most have inflight access to a pressurized aft baggage compartment.

The origins of today’s super-midsize class date back almost half a century. In the early 1960s, Grumman embarked upon development of the GII, a large-cabin, transcontinental range turbofan business aircraft, capable of flying coast-to-coast at true jetliner speeds. Building upon the success of its large-cabin Gulfstream I turboprop, Grumman engineers retained the basic fuselage tube and stretched the cabin by almost 4 ft. They added mildly swept wings, a T-tail and two pylon-mounted Rolls-Royce Spey engines to create the new model.

Customers, especially GI operators, eagerly signed orders for the new aircraft, well in advance of Grumman’s building a mock-up. Similar to the GI, the GII would have a flat floor, more than 6 ft. of headroom, a 7.2-ft. maximum cabin width and signature wide, oval windows. The cabin had room for a forward four-seat club section, a mid-cabin conference grouping and a single aft, forward-facing CEO’s chair flanked by a small divan. It could fly most coast-to-coast trips at 440 to 450 KTAS and had a maximum range of 2,600 to 2,700 nm at long-range cruise. That range enabled the GII to transport eights passengers between most U.S. coastal city pairs, if headwinds were moderate. It also could fly between most North American and European cities with one fuel stop.

The market responded quickly and enthusiastically. Grumman management slashed a full year from the sales promotion campaign and proceeded directly to cutting metal for the first production conforming aircraft. GII s.n. 001 sprinted off Grumman’s Bethpage, N.Y., runway in late 1966 and earned its FAA type certificate in October 1967.

Grumman went on to deliver 258 aircraft in the next 12 years. The GII was succeeded by the GIII in 1980, GIV in 1987 and GV in 1997, among other derivatives. While its successors were faster and had more range, the basic need for a coast-to-coast range business jet offering 450-plus KTAS cruise speeds and a comfortable cabin for eight or more passengers never went away. GII production ended in 1967, leaving a market segment that wasn’t filled for 25 years. In spite of all its assets, the GII eventually was doomed to obsolescence because of its 4,000-pph fuel thirst and ear-splitting jet roar.

“We left an opportunity for others when we abandoned that market niche. For years, there never was an aircraft in that segment to fill the void,” said Pres Henne, Gulfstream’s senior vice president programs, engineering and test.

IAI Astra IV

Astra Jet Corp., the U.S.-based business aircraft marketing arm of Israel Aircraft Industries, announced development of the IAI-1126 Astra IV at the September 1992 NBAA Convention in Dallas. Developed from the IAI Astra SP light-medium jet, the Astra IV would retain its basic wing airfoil, airframe systems and cruciform tail design.

The Astra IV would have a large, circular tube-shaped fuselage, with a shallow dropped aisle, affording passengers 6.1 ft. of headroom, 7.0 ft. of cabin width and 24.3 ft. of cabin length. While overall length of the main passenger seating area was somewhat shorter than that of the GII, the Astra IV offered almost as much seated head and shoulder room as the GII.

IAI was ambitious in its goals for the program. The Astra IV would be able to fly four passengers 3,650 nm while cruising at 430 to 435 KTAS and land with NBAA reserves. It would be able to fly eight passengers, coast-to-coast in the United States while cruising at 476 KTAS. Just as importantly, the Astra IV at $13 million would be priced competitively with midsize aircraft and it would rival their direct operating costs.

The key to achieving the price point was to partner with outside firms to share the development costs. Design tradeoffs, however, became necessary to meet the cost goals. The relatively small wet wing, adapted from the Astra SP, required fitting the aircraft with a large aft fuselage tank that reduced available cabin length and precluded inflight access to the aft baggage compartment.

Instead of upgrading to a hot wing anti-ice system, the Astra SP’s deice boots were retained to protect the leading edges. The engines retained relatively heavy starter-generators so that DC electrical power, rather than high-pressure air, could be used for starting. The electrical system retained the Astra’s parallel bus design rather than embracing a more modern split bus architecture.

The Astra IV also used the Rockwell Collins Pro Line 4, similar to the Astra SPX. A fifth CRT was added to the instrument panel, adding EICAS and rudimentary systems synoptics capabilities.

Controlling weight as aggressively as a French fashion model was critical to achieving range, speed and payload goals, along with holding down direct operating costs. The Astra IV initially was projected to have an 18,150-lb BOW and 32,500-lb MTOW, roughly half the weights of the GII. IAI selected Pratt & Whitney Canada to supply highly efficient, but modestly sized PW306A engines. If the Astra IV gained weight, the engines would not have the margins needed to produce enough thrust to offset the added girth.

Perennially cash-strapped IAI courted equally lean Yakovlev Aircraft as a potential joint-venture partner to build the airframe. Eventually, both IAI and Yakovlev conceded that they lacked the resources to bring the Astra IV to market. But six years later, Fort Worth-based Galaxy Aerospace, backed by a large cash infusion from the Pritzker family and under the leadership of industry veteran Brian Barents, finally propelled the Astra IV, reborn as the Galaxy, into the market.

Gulfstream was so impressed with the Galaxy’s potential as a GII replacement, that the company acquired the program and renamed the aircraft G200 in 2002. However, by then the aircraft’s BOW had ballooned to nearly 20,000 lb, necessitating an increase in MTOW to 35,450 lb. Having 6,040-lb-thrust engines and 369 ft. of wing area that were adequate for a 32,500-lb aircraft, the G200’s nearly 10% higher takeoff weight resulted in mediocre takeoff and climb performance. That left unfulfilled some of the promises of the original aircraft. A typically equipped G200 can carry only two passengers with full fuel. But it can still fly eight passengers 3,100 nm at Mach 0.75. Currently, new G200 aircraft are priced at $23 million. But with its successor less than two years away from certification, prices are soft due to tepid demand.

Hawker Horizon

Four years after the announcement of the Astra IV, Raytheon Aircraft Co. (now Hawker Beechcraft Corp.) unveiled the $14.5 million Hawker Horizon, a revolutionary new composite fuselage/aluminum wing aircraft, at the 1996 NBAA Convention. The new Hawker would “retain the [legacy] Hawker’s classic look and feel,” but would offer large-cabin aircraft class avionics and systems, a high-speed, super-critical airfoil and a thorough aerodynamic clean-up.

Raytheon positioned the Horizon as a step-up product from the legacy Hawkers. It could fly considerably higher, faster and farther than any British-designed Hawker, plus it would have much improved hot-and-high takeoff performance.

Maximum range was set at 3,400 nm at Mach 0.78 and Raytheon guaranteed the airplane would be able to fly 3,100 nm at Mach 0.82, assuring the aircraft would have transcontinental U.S. range against virtually any probable headwind.

The overall 7.0-ft. outside diameter of the fuselage would be virtually the same as the all-aluminum legacy Hawker 125 series, but the more structurally efficient, sandwich construction composite fuselage tube would increase maximum cabin height to 6.0 ft. and width to 6.5 ft. Overall cabin volume would be 60% greater than that of the Hawker 800XP, which was the large-cabin midsize aircraft at the time. This would make room for two full seating areas. The Hawker Horizon also would have a flat floor, inflight access to the aft baggage compartment, a full-service forward galley and a full-width aft lavatory, all much-desired design features in the super-midsize class.

H. Sam Bruner, a prime architect of the GIV and lead engineer on the Hawker Horizon, embraced large-cabin aircraft design standards for the new aircraft. The Horizon would have long-life, low maintenance, brushless AC generators powering TRUs that supplied a split bus DC electrical system, dual Honeywell Laseref IRS boxes, dual air cycle machines, bleed air wing anti-ice, along with fly-by-wire rudder and spoileron controls, plus a best-in-class 6,000-ft. maximum cabin altitude. It also would be the launch platform for Honeywell’s new Primus Epic flat-panel avionics system and it would be the first aircraft in class to have full-authority autothrottles, vertical navigation and an integrated performance computer.

Bruner wanted the Horizon to offer a legacy Gulfstream’s sporty performance. Similar to the GIV, it would have a generously sized 531-sq.-ft. wing and ample engine thrust to assure margin for weight growth. The original estimated maximum takeoff weight was 36,000 lb and each PW308A turbofan engine was to be rated at 6,500 lb. Estimated standard-day takeoff distance was 5,250 ft.

Raytheon boldly predicted first flight would occur in late 1999, with type certification and initial customer deliveries to commence in second quarter 2001. But the development program became mired in difficulties and composite fuselage manufacturing was plagued by process control hiccups. Some at Raytheon wondered if the Horizon program was too ambitious for the capabilities of its legacy engineering department in Wichita.

Initial FAA type certification finally occurred in November 2006. Along the way, Raytheon renamed the aircraft Hawker 4000. The program continued to stumble along with numerous post-certification IOUs due customers. Only a dozen production aircraft were delivered before 2009. EASA certification wasn’t received until May 2010.

On balance, though, the Hawker 4000 is maturing into a strong player in the super-midsize league. Bruner’s foresight in providing plenty of wing and engine margins proved critical. When the empty weight of the aircraft ballooned by 2,700 lb, MTOW was bumped up to 39,500 lb and they asked P&WC to crank up engine thrust to 6,900 lb. There was ample wing and thrust to compensate for the weight gain. Actual takeoff distance decreased to 5,068 ft.

But the extra bulk did cause range performance to suffer by 300 nm. With eight passengers, the Hawker 4000 can fly just over 3,100 nm at Mach 0.80. However, it’s still the only currently certified super-midsize aircraft that can carry seven passengers with full fuel.

Hawker Beechcraft has delivered fewer than 60 Hawker 4000 aircraft in the past four years. In an attempt to stimulate sales, it’s holding down the price to $22 million, a bargain considering this aircraft’s capabilities and systems sophistication.

Bombardier Challenger 300

Not long after Raytheon’s announcement of the Hawker Horizon development program, Bombardier embarked upon a two-year clandestine super-midsize engineering program. Bombardier’s $14.25 million Continental was unveiled at the 1998 NBAA Convention and officially launched at the 1999 Paris Air Show. First metal was cut in October 1999 as Bombardier rushed toward a planned June 2001 first flight, September 2002 type certification and December 2002 customer deliveries.

Market focus groups told Bombardier they wanted much the same performance characteristics as the Hawker Horizon offered. In response, Bombardier projected that the Continental would be able to fly eight passengers 3,100 nm at Mach 0.80 and land with NBAA IFR reserves. That range performance would assure transcontinental U.S. range against 80-plus kt. headwinds. It would need less than 5,000 ft. of runway for takeoff, assuming standard day conditions and it would have rock bottom direct operating costs because of a maintenance friendly, MSG-3 design.

Of prime importance to its legacy customers, the Continental would have a significantly wider cross section than its archrival Hawker Horizon. Its cabin would measure 7.1 ft. wide and 6.0 ft. high. It also would feature a flat floor, full-service galley, full-width aft lav and inflight accessible baggage compartment. The main cabin would feature double club seating in two areas.

John Holding, Bombardier’s head of engineering, endowed the new aircraft with a generously sized wing and ample thrust engines. The Continental would be the launch customer for AlliedSignal’s new 7,000-lb-thrust class AS907 turbofan, an engine that balanced low maintenance costs and high reliability with good fuel efficiency.

The Continental would feature a four-screen Rockwell Collins Pro Line 21 avionics suite with full EICAS. While the system is quite capable, Bombardier and Collins froze the configuration without making provisions for an optional synthetic vision system, HUD or enhanced vision system.

To minimize development risk, the Continental would embrace proven technologies, similar to the Astra IV. Holding specified conventional aluminum monocoque construction for the airframe. The Continental also would feature an all-DC, split bus electrical system powered by two brushless generators, two independent hydraulic systems and a brake-by-wire system using carbon heat packs and a single air cycle machine refrigeration pack.

Along the way to certification, Bombardier encountered a few snags that delayed the program by a few months. But there were no major showstoppers on the way to certification. While sorting out the snags, Montreal renamed the aircraft Challenger 300 in an attempt to give it a more up-market image.

Simultaneously, AlliedSignal, then merged with Honeywell, encountered some engine reliability problems that could have irked early operators and perhaps delayed certification. Honeywell announced that the certification date was being rolled back so the engineers could improve durability. In the process, Honeywell scrubbed the AlliedSignal AS907 engine name and dubbed it the HTF7000. The engineering delay proved valuable. When the Challenger 300 entered service in late 2003, the HTF7000 proved to produce more cruise thrust than forecast and also achieve better fuel efficiency.

Soon, operators became Bombardier’s best sales force. They boasted that the aircraft would climb directly to FL 430 and cruise at Mach 0.82 or faster. They could fly eight passengers from coast to coast at Mach 0.80, just as Bombardier promised. And the aircraft proved to be exceptionally reliable.

Operators also said they loaded up the aircraft with optional equipment. That resulted in a payload of only four passengers with full fuel. Each additional passenger costs about 50 to 60 mi. of range, so the Challenger 300 has an eight-passenger range that’s close to 3,000 nm, which is still impressive for this class of aircraft.

Bombardier has delivered more than 300 Challenger 300 aircraft and its sales success has encouraged it to bump up the asking price. Typically equipped, the Challenger 300 now is priced at above $25 million.

Embraer Legacy 500

The Brazilian airframe manufacturer’s first foray into the super-midsize segment is impressive. Announced at EBACE 2008 in Geneva and due to enter service in late 2012, Embraer is positioning the $19 million Legacy 500 to be the value leader in the super-midsize class. It features a 26.8-ft.-long passenger cabin with a 6.0-ft. height and 6.9-ft. width, thus its cross section is between that of the Hawker 4000 and Bombardier Challenger 300 while its cabin is slightly longer. Its 860-cu.-ft. cabin volume equals that of the Challenger 300.

The Legacy 500 has a flat floor, the largest windows in class and a 6,000-ft. cabin altitude at maximum cruise altitude, the same as the currently class-leading Hawker 4000. Similar to other super-midsize aircraft, there are two main seating sections, plus a full galley up front and a full-width lavatory with a window in the aft cabin. It has a 110-cu.-ft. aft external baggage compartment that is not accessible in flight because it is aft of the rear pressure bulkhead. But the aircraft has an additional 40 cu. ft. of carry-on luggage space for laptops and personal items.

The cabin will be available with five interior seating configurations, including various combinations of two-place club chairs and three-seat divans. A two-seat, right-side divan may be ordered in place of the forward galley. A belted potty seat will be an option.

Embraer estimates that the aircraft will have a 2,800-nm eight passenger range when cruising at Mach 0.80, but the firm is notorious for understating the performance of its business aircraft prior to certification. This aircraft may roll out with close to a 3,000-nm cruising range, in BCA’s opinion. Full fuel payload is 1,600 lb.

Both the Legacy 500 and the smaller, shorter range Legacy 500 are powered by Honeywell HTF7500E turbofan engines. The firm predicts the Legacy 500 will have a 4,600-ft. takeoff field length, assuming standard day conditions. That’s best-in-class runway performance. It also will be able to climb directly to FL 430 in 22 min.

The Legacy 500 and its shorter-range sibling, the Legacy 450, are the first aircraft in this class to be fitted with digital flight control systems and side control sticks. They also will be equipped with Embraer’s Prodigy flight deck, featuring four 15-in., landscape configuration Rockwell Collins Pro Line Fusion flat-panel display avionics. Synthetic vision, autothrottles and graphical flight planning are standard. Laptop computers will support Embraer’s comprehensive OPERA flight planning software that fine tunes runway and climb performance computations.

Options include Collins MultiScan weather radar with predictive wind shear, RNP 0.3 certification, HF radio, HUD with enhanced vision system, data-link graphical weather and FMS performance computer.

Because of its price point, Embraer is positioning the Legacy 500 as a direct competitor to smaller, midsize aircraft, such as the $17 million Citation Sovereign, $15 million Gulfstream G150 and $16 million Hawker 900XP. Its runway performance is better than any midsize aircraft except for the sprightly Citation Sovereign and it has more range with eight passengers than any business aircraft at its price point.

But it’s truly a super-midsize jet and it will compete against similarly sized aircraft that have more range.

Gulfstream G250

The $24 million Gulfstream G250 is the spiritual successor to the Gulfstream II, even though the airframe is built by IAI in Tel Aviv. Slated for certification this year, the G250 retains the G200’s basic fuselage tube created for the Astra IV, thus it has the widest and highest cabin cross section in the super-midsize class. The usable cabin length is one-third longer than the G200 because the aft fuselage fuel tank has been eliminated. The increased cabin length also makes room for two additional cabin windows on each side of the aircraft. In addition, without the aft aux tank, passengers also have inflight access to the aft baggage compartment.

True to the high-performance legacy of Savannah-built Gulfstream aircraft, the G250 has a large, 495-sq.-ft. wing that incorporates G550 transonic airfoil aerodynamics, a T-tail and powerful Honeywell HTF7250G turbofans, rated at 7,445 lb thrust for takeoff. It has the sportiest thrust-to-weight ratio in the super-midsize class, the longest range, the highest maximum mach cruising speed and the best fuel efficiency at Mach 0.80. It can fly eight passengers 3,200 nm while cruising at Mach 0.80, thus becoming the class leader in range/payload performance. That’s impressive because the G250 actually has less fuel capacity than the G200 and it has a 3,950 lb higher empty weight. But it climbs quicker, cruises higher and faster, plus it squeezes more miles out of each pound of fuel because of its superior wing aerodynamics and more-efficient engines.

The G250 promises to offer the shortest takeoff field lengths on equal length missions of any super-midsize class aircraft, including the Challenger 300. The G250 owes its strong runway performance to a classic Gulfstream blend of relatively low wing loading and high thrust-to-weight ratio.

Aircraft systems have been upgraded. Similar to the Challenger 300, the G250 has relatively small, manually actuated ailerons to provide natural aerodynamic feedback, as well as jammed flight control disconnect protection. The ailerons are complemented by comparatively large, fly-by-wire spoilerons to provide robust roll control authority. The rudder has dual fly-by-wire digital control systems and the elevator has dual hydraulic actuators with jammed flight control disconnect protection. Similar to the G650, the tail has a fully trimmable stabilizer.

Up front, pilots will find Gulfstream’s signature PlaneView250 avionics suite, based upon Collins Pro Line Fusion and featuring three, landscape-configuration, 15-in. displays along with dual Honeywell Laseref IV IRS units. Autothrottles and JeppView electronic charts are standard. An optional second file server will make possible paperless chart operations. Portable PlaneBook computer tablets will host electronic AFM, QRH, weight-and-balance and operating manuals.

Synthetic vision and Gulfstream’s second-generation HUD and enhanced vision systems will be optional, as will be XM radio weather, predictive wind-shear weather radar and electronic en route charts. Similar to other super-midsize aircraft, the G250 will feature brake-by-wire. But it also will have an auto-braking system.

Gulfstream long has been known for its cabin completions expertise and the G250 will benefit from advancements developed for its Savannah-built aircraft. The cabin will feature Gulfstream’s Cabin Essential architecture that provides avionics-like fail-active, dual-channel redundancy for lighting, temperature control, entertainment, water and waste systems.

Next-Generation Super Midsize Aircraft

Almost two decades ago, the Astra IV became the first super-midsize business aircraft, launching an all-new market segment. Since then, four business aircraft manufacturers have entered the market, each one offering a distinctive blend of qualities.

The Astra IV/Galaxy/G200 had the best cabin cross section, an evolutionary airframe and simple systems, but mediocre runway, climb and cruise performance. However, the Galaxy was first to market and it gained early sales success. Raytheon (now Hawker Beechcraft) pursued a revolutionary design with its Hawker Horizon/4000, having a lean cabin cross section, strong performance and sophisticated systems modeled after those of the Gulfstream IV. The Bombardier Continental/Challenger 300 embraced a low-risk approach, but it is endowed with a wider cabin and equally strong performance.

In the last two to three years, the second-generation super-midsize aircraft made their debut. Embraer jumped in with the Legacy 500, promising best-in-class value as well as fly-by-wire flight controls. Gulfstream capitalizes on lessons learned from its Savannah-built aircraft, enabling the firm to transform the matronly G200 into the sporty G250, a true Gulfstream by any measure.

The second-generation super-midsize business aircraft continue a trend toward offering passengers more cabin volume, better fuel efficiency, a lower noise signature and reduced carbon emissions. Newer super-midsize models also have better takeoff field performance than first-generation aircraft in this class, along with advanced avionics systems that rival those of large-cabin aircraft, such as paperless charts, synthetic vision systems, HUDs with enhanced vision systems and high-speed Internet access.

Clearly, customer expectations are being raised. Some emerging aircraft will blur the distinction between super-midsize and large-cabin business aircraft. Dassault’s super-midsize aircraft, for instance, is likely to be based upon its large-cabin Falcon 7X. If the economy improves enough to warrant Cessna’s reviving its Citation 850 Columbus program, that super-midsize should be able to fly as far as a large-cabin Challenger 605 as well as cruise faster. Embraer could counter with a higher thrust version of the Legacy 600 that would offer improved takeoff performance, retain its ability to fly eight passengers more than 3,200 nm at high-speed cruise and provide the largest cabin in class.

The future of the super-midsize class looks bright. A large segment of business aircraft operators still need an aircraft that fills the gap left in the market when Gulfstream ceased production of the GII in 1979. The core requirements remain unchanged. Super-midsize operators want a comfortable and useful cabin including a fully flat floor, full-service galley, full-width aft lav and full-time access to all baggage. The aircraft should be able to fly eight passengers with 3,000-plus nm range at Mach 0.80. Strong short-field performance is a major asset because it provides access to thousands of close-in general aviation airports. To be viable in the super-midsize class, an aircraft must have acquisition and operating costs well below the bottom of the heavy-iron class.

Not all super-midsize aircraft offer all of these assets. But each has a personality, performance capabilities and a price point that distinguishes it from its competitors. The segment will expand as new models make their debut in response to market demand. Look for SMS to grow into one of the largest niches in the business aircraft market. BCA