BOEING 767 VARIANTS:

The 767-200ER : The 767 tanker is a high performance version of the 767-200ER twin aisle jetliner equipped for fully integrated tanker operations. 767-200ER is an extended range version announced in 1983 seating 181 to 224 passengers. The range is up to 12,325km. The aircraft first flew in 1984 with first delivery in 1984 to El Al airlines.

The Boeing 767-300ER, around 6.43m (21ft) longer than the 200ER, provides seating for 218 to 269 passengers and has a range up to 11,389km. First flight was in 1986 with first delivery in 1988 to American Airlines.

The 767-300 Freighter, launched in 1993 and first flight in 1994, has a freight volume capacity of 16,034m³ and a range of 5,560km. First delivery was in 1995 to United Parcel Service.

The 767-400ER, around 6.43m (21ft) longer than the 300ER, is the latest member of the 767 family and the first flight took place in October 1999. The stretched aircraft provides seating for 304 passengers in two-class cabin layout and 245 seats for passengers in a three-class layout. The 767-400ER entered service with Continental Airlines (total order 16) in September 2000 and with Delta Airlines (total order 21) in October 2000. The 767-400ER features aerodynamic improvements, including new raked wing tips, increased takeoff weight capability, a new main landing gear, and a new upgraded flight deck. The new, highly Tbackswept (raked) wing-tip extensions increase the 767's 156ft wingspan to 170ft 4in (52m). The 7ft 8in (2.4m) wing extensions are designed to increase the aerodynamic efficiency of the wing and thus improve the range.

FLIGHT DECK:The flight deck, which accommodates the pilot and co-pilot is similar to that of the 757. The aircraft's flight instrument system is the Honeywell EFIS-700.The navigation suite includes Honeywell VHF omnidirectional radio, an integrated instrument landing system, and a marker beacon receiver, an automatic direction finder, distance measuring system and a radio magnetic indicator RMI-743. There are dual digital flight management systems and triple redundant flight control computers. The aircraft carries CAT IIIb landing certification.

Rockwell Collins has developed a Large Format Display System, which has been fitted in the 767-400ER. The system incorporates six 203mm x 203 mm (8in x 8in) liquid crystal displays.

The 767 aircraft in service with All Nippon Airways, Britannia Airways and Transbrasil are fitted with the Honeywell RDR-4A colour weather radar.

ENGINES: The aircraft has two turbofan podded engines mounted below the leading edges of the wings. The available engines are General Electric CF6-80 (A 767-400 engine nacelle being fitted to A General Electric CF6-80C2B jet engine.)engines rated at 225kN to 276kN, Pratt and Whitney PW 4052, 4056, 4060 and 4062 rated at 233 to 282kN and the Rolls Royce RB211 rated at 251kN and 265kN.

The auxiliary power unit is installed in the tailcon.

LANDING GEAR.

The aircraft is equipped with hydraulically operated, retractable tricycle type landing gear. The forward retracting nose unit supplied by Menasco has twin wheels. The inward retracting main landing gear supplied by Cleveland Pneumatic is fitted with two four wheeled bogies. The wheels are supplied by Honeywell. The main landing gear has steel disc brakes and a hydraulically actuated tail skid.

Wing design: The Boeing 777 wing is the most aerodynamically efficient airfoil ever developed for subsonic commercial flight. With a long wing span of nearly 200 feet and a high aspect ratio (8.68), the design gives Boeing ample freedom to grow the plane. With an upper skin made of the new 7055 aluminum alloy from Alcoa, which resists fatigue and corrosion, the airfoil carries a lot more lift towards the trailing edge than in any other Boeing jetliner. The design enhances the airplane's ability to climb quickly and cruise at higher altitudes.

Propulsion systems: The three engine manufacturers--General Electric, Pratt & Whitney, and Rolls Royce--all developed new and more powerful turbofans for the 777. For the initial plane, these engines are rated in the 74,000 to 77,000-lb thrust class. For longer-range models, the same engines can provide 84,000 to 90,000 lbs of thrust and could be developed for even higher thrust ratings, depending on future payload and range requirements. Although these engines are 40% more powerful than those used on the smaller Boeing 767, they are just as quiet. Key factors in this performance are larger-diameter fans with wide-chord blade designs and bypass ratios ranging from 6-to-1 to as high as 9-to-1, compared to the typical 5-to-1 ratio for engines on previous wide-body jets.

Also notable: the Pratt & Whitney engines on the first 777s put in service were FAA-approved from the outset for 180-minute, extended-range, twin-engine operations (ETOPS). This gives pilots many alternate airport choices all along the way.

Flight deck and systems: Principal flight, navigation, and engine information appear on six large flat-panel display screens. Besides saving weight and space, the new displays consume less energy and do not require the heavy, complex air conditioning apparatus needed on current flight decks. In addition, three multipurpose control display units, installed in the flight deck's center aisle stand, interface with an integrated Airplane Information Management System (AIMS). This modular avionics concept--a first for commercial jetliners--provides all pertinent information concerning the overall condition of the airplane, its maintenance requirements, and key operating functions.

In addition, a patented two-way digital data bus permits airplane systems and their computers to communicate through a common wire path instead of through separate one-way wire connections. This saves weight and boosts reliability.

The flight crew transmits control and maneuvering commands through electrical wires, augmented by computers, directly to hydraulic actuators for the elevators, rudder, ailerons, and other control surfaces. Such fly-by-wire systems reduce weight, simplify factory assembly, and ease maintenance.

New materials: Composites make up about 10% of the structural weight of the 777, far more than on any previous Boeing jetliner. You'll find composites--primarily carbon-fiber reinforced plastics--in the 777's floor beams, engine cowlings, flight control surfaces, landing gear doors, and wing-to-body fairings, and empennage.

Passenger space:One of the most spacious passenger cabins ever developed, the 777 interior offers great flexibility, allowing airlines to make easy changes to seating, galley, and lavatory configurations. Passenger service units and overhead stowage compartments can be quickly removed without disturbing ceiling panels, air conditioning ducts, or support structure. A typical 777 configuration change, such as converting from three-class to two-class service, takes as little as 72 hours, compared to two or three weeks on existing aircraft.

For the passenger's comfort, overhead compartments not only offer greater storage capacity but fit neatly into the streamlined contours of the interior structure, allowing for more head room. Depending on the airline, some 777s will be equipped with personal entertainment systems, featuring compact viewing screens and hand-held controllers for movies, video games, and flight information.

The Industrial Designer's Society of America gave the 777's passenger cabin its Design Excellence Award, the first time an airplane interior has won such honors.

The 777 family. Though Boeing delivered its first 777s in 1995, it already is planning future versions of the plane that will expand both passenger and range capacity. From the initial model, which carries from 305 to 375 passengers, the big twin will get stretched to accommodate as many as 550 people in a single-class, high-density configuration. Future versions, such as a 777-100x, would bring non-stop service to destinations as far away as 8,000 nautical miles. .

The 757 and 767. Introduced in the early 1980s, both are powered by very fuel-efficient twin engines. With a single-aisle configuration, the 757 typically carries 186 passengers in two classes up to 3,900 nautical miles. A new 757-300X model now under consideration would hold 20% more passengers and travel 600 nmi farther. Similarly, the larger, twin-aisle 767 could be slated for changes. Now carrying 220 to 300 passengers and with a range of up to 6,000 nmi, the plane would boost passenger and cargo capacity by 20% in a 767-400X model under study.

Click to see the Reference: Design News: For the Love of Flying By Lawrence D. Maloney Editorial Director Design News March 4, 1996

1. Even if the 764 is the 7-6 candidate, it's still a minimum of $15 million cheaper than the 777-200 2.

2. The prices could change dramatically when in military form) If the USAF were to buy 200 airframes, that's at least $3 billion less dollars.

3. More 767's than 777's.

1. There always was the option for airlines, but no one was interested in it.

2. the folding wings would decrease the ramp "footprint" of the aircraft

3. If the USAF were to buy 200 airframes, that's at least $3 billion more dollars.

4. They could get by with fewer 777's than 767's.

Reducing the massive number of tankers (currently 500+ KC-135 counting AF, ANG, and AFRes) is great, but taking it to the extreme of a small number of 777's may be a bit overboard.

KC-135 Maximum Takeoff Weight(MTOW): 322,500 Lbs KC-767 MTOW:

450,000Lbs, MD-11 MTOW:630,000, KC-10 MTOW: 590,000.

B-777 MTOW: 660,000.

777-200LR (MTOW 766,000 lbs)

1. 777 with the folding wing.

2. More capacity than the 767

The 767 already has a cargo door available for both the -200 and -300.

As an added bonus, the military is already equipped with a 767-200 medevac interior kit, where the KC-767 can pick up the slack for the loss of C-141 and C-9 medevac.

KC 777-200 would be a decent supplement to the KC-10 fleet,

The large tanker fleet is much too small to consider replacing any of the KC-10s.

You end up with much more unused (wasteful) capacity in an MD-11/777/A330 tanker.

To meet numbers : KC-777-200's, would need 323 of them: costing $50 - $55 billion

KC-777-200ER's would need 268 of them: costing $44 - $49 billion

KC-777-200LR's we would need 230: costing $43 - $49 billion

KC-777-300's we would need 266 of them: costing $47 - $53 billion

KC-767 will be (it is already ordered for Italy and Japan) superior to the KC-135.

The Pentagon might well have considered nuclear survivability to be important for tanker aircraft, more so than transports like the C-17 as they will be operating in the front line.

Costs for used 767-300ER aircraft vary between $51M and $88M

In terms of speed its Mach 0.8 performance compares to the Mach 0.85 or better performance of the KC-135 aircraft.