Lockheed L-1011 TriStar

The Lockheed L-1011 TriStar, commonly referred to as just L-1011 (pronounced "ell-ten-eleven"), was the third widebody passenger jet airliner to enter operation, following the Boeing 747 and the McDonnell Douglas DC-10. Like the DC-10, the Tristar is a three engine jet airliner. Between 1968 and 1984, Lockheed manufactured a total of 250 TriStars. After production of the L-1011 TriStar, Lockheed withdrew from commercial aircraft business due to its below target sales.

Design and development

In the 1960s, American Airlines approached Lockheed and competitor Douglas with the need for an airliner smaller than the 747, but still capable of carrying a large passenger load to distant locales such as London and Latin America from company hubs in Dallas/Ft Worth and New York. Lockheed had been largely absent from the civil airliner market since the late 1950s following problems with its L-188 Electra which had suffered a number of crashes. However, having experienced difficulties with some of its military programs, Lockheed was keen to re-enter the civil market, and its response was the L-1011 TriStar. The aircraft was originally conceived as a design having two engines but such plans were abandoned in favor of a third engine.

The design featured a twin-aisle interior, low noise emissions (in the early 1970s, Eastern Air Lines nicknamed the L-1011 TriStar "The WhisperLiner"), improved reliability, and efficient operation. American Airlines opted for the Douglas DC-10, although it had shown considerable interest in the L-1011. American's intent in doing so was to convince Douglas to lower its price for the DC-10, which it did.

Without the support of American, the TriStar was launched on orders from TWA and Eastern Air Lines. Although the TriStar's design schedule closely followed that of its competitor, the DC-10, Douglas beat Lockheed to market by a year due to delays in powerplant development. In February 1971, after massive development costs associated with the TriStar's RB211 turbofan engines, Rolls-Royce filed for bankruptcy. This halted L-1011 final assembly, but by then it was too late to change engine suppliers (to either General Electric or Pratt & Whitney). The British government agreed to approve a large state subsidy to restart Rolls-Royce operations on condition that the U.S. government guarantee the bank loans that Lockheed needed to complete the L-1011 project. Despite some opposition, not least from the then Governor of California Ronald Reagan, the U.S. government provided these guarantees.

File:L1011tristarlogo.png

Logo of the Lockheed L-1011

Designed for a maximum seating of 400 passengers, the TriStar had an engine layout with Rolls-Royce turbofan jet engines below each wing, and a third engine was located at the base of the vertical stabilizer. Manufactured in Lockheed facilities in Burbank and Palmdale, California, the TriStar faced brisk competition with the Boeing 747 and, even more directly, the McDonnell Douglas DC-10, which it closely resembled. The TriStar had a better safety record than the DC-10, and Trans World Airlines heralded the TriStar as one of the safest airplanes in the world in some of its promotional literature in the 1980s when concern over the safety record of the DC-10, which was flown by most of its competitors, was at its peak. However, the DC-10 outsold the TriStar nearly two to one, partly because of the TriStar's delayed introduction but particularly because a heavier, longer range version was not initially offered. Under state control, costs at Rolls-Royce were tightly controlled and the company's efforts largely went into the original TriStar engines, which had needed considerable modifications between the L-1011's first flight and service entry. The competition, notably General Electric, were very quick to develop their CF6 engine to higher thrust, which meant a heavier 'intercontinental' DC-10-30 could be brought to market. The flexibility afforded to potential customers by a long range DC-10 quickly put the L-1011 at a serious marketing disadvantage. Rolls-Royce went on to develop the high thrust RB211-524 for the L-1011-200 and -500, but this took many years.

The main visible difference between the TriStar and DC-10 is in the middle/tail engine; the DC-10's engine is mounted above the fuselage for more power, while the TriStar's engine is integrated into the tail through an S-duct (similar to the Boeing 727) for improved quietness and stability. The earlier versions of the L-1011, such as the -1, -100, and -150 can be distinguished from the later models by the design of the middle engine nacelles. The earlier version nacelle has a round intake while the later designed models have a small vertical fin between the bottom of the middle engine intake and the top of the fuselage.

The L-1011 was the first widebody to receive FAA certification for Cat-IIIc autolanding, which approved the TriStar for completely blind landings in zero-visibility weather. It also had a unique Direct Lift Control (DLC) system, which allowed for smooth approaches when landing. DLC helps maintain the descending glideslope on final approach by automatically deploying spoiler panels on the wings. Thus, rather than maintaining the descent by adjusting pitch, DLC helps control the descent while maintaining a more consistent pitch angle; four redundant hydraulic systems (the DC10 and MD11 had only three); production also utilized a unique "autoclave" system for bonding fuselage panels together. This made the L-1011 extremely resistant to corrosion.

The TriStar's internal Lockheed model number is L-093.

The prototype first flew on November 16, 1970. The crew for that flight was H. B. Dees (pilot), Ralph C. Cokely (copilot), and G. E. Fisher (development engineer). The first TriStar was finally delivered to Eastern Air Lines on April 26, 1972.

Lockheed bribed the members of the Japanese government to subsidize ANA's purchase of L-1011s. The resulting political scandal led to the arrest of Prime Minister Kakuei Tanaka. Within Lockheed, board chairman Daniel Haughton and vice chairman and president Carl Kotchian resigned from their posts on February 13, 1976. Tanaka was eventually tried and found guilty of violating foreign exchange control laws, but was not charged with bribery, a more serious criminal offense.

Lockheed needed to sell 500 planes to break even, but in 1981 announced that production would end with delivery of the 250th and last plane on order in 1984. The TriStar's failure to achieve profitability caused Lockheed to withdraw from the civil aircraft business.

Operational history

Civil aviation

Civilian operators of the Tristar included Aer Lingus, AeroPeru, Air Atlanta Icelandic, Air Canada, Air France, Air Luxor, Air Transat, Air Lanka, All Nippon Airways, Arrow Air, ATA Airlines, British Airways, British Caledonian, Caledonian Airways, BWIA, Cathay Pacific, Court Line, Delta Air Lines, Eastern Air Lines, EuroAtlantic, Fine Air, Faucett, Gulf Air, Hawaiian Airlines, Iberia L.A.E., LTU, Luzair, National Airlines, Orient Thai, Pan Am, Peach Air, PSA, Royal Jordanian, Saudi Arabian Airlines, Skygate, TAAG Air Angola, TAP Air Portugal, TWA, United Airlines, Worldways Canada.

Delta Air Lines was the type's largest customer. Cathay Pacific eventually became the largest non-U.S. operator of the type by acquiring many of the Eastern Air Lines examples when Eastern Air Lines went bankrupt, operating as many as 21 aircraft.

Most major airlines have retired the type from their fleets. Cathay Pacific retired its L-1011 fleet in October 1996, replacing the fleet with Airbus A330-300. TWA withdrew its last TriStar from service in 1997. Delta retired its TriStar fleet in 2001, replacing them with the Boeing 767-400ER.

The L-1011 still sees use by smaller start-up carriers, particularly in Africa and Asia. These operators mainly do their business in the ad hoc charter and wet leasing businesses. ATA Airlines (formerly known as American Trans Air) still actively operates four L1011-500s. These aircraft are used on military charter flights conducted by ATA, however, due to the lack of maintenance and spare parts reliability, ATA has scheduled their remaining L1011s to be put out of service by October 2007.

Military and government

A Royal Air Force Lockheed TriStar. The two refueling points under the rear fuselage are painted with red stripes for visibility.

The TriStar has also been used as a military tanker and passenger/cargo aircraft. The Royal Air Force has nine aircraft of four variants. The aircraft are ex-British Airways and Pan Am L-1011-500s. Two of the aircraft are designated TriStar K.MK 1s and are pure tankers. Another four are KC1s and can be either tankers or passenger/cargo aircraft. The two TriStar C.Mk 2 models and the solitary TriStar C. Mk 2A are pure passenger aircraft. The C2A differs from the C2 by having military avionics and radios. The RAF's TriStars were bought in the immediate aftermath of the Falklands War to bolster the long range capability of the RAF in the transport and tanker roles. All of the aircraft serve with No. 216 Squadron, based at RAF Brize Norton.

The aircraft have seen service in many recent conflicts. Two were deployed to King Khalid International Airport, near Riyadh in Saudi Arabia during the 1991 Gulf War as tankers, with the rest used for transport between the Persian Gulf and UK. The two aircraft deployed received nose art naming them Pinky and Perky. During the 1999 Kosovo War, TriStars deployed to Ancona in Italy, again as tankers, with four aircraft involved. TriStars joined VC-10s in the AAR role for Operation Veritas (Afghanistan), during which they provided aerial-refueling for US Navy aircraft. Their most recent wartime role was again over the skies of Iraq. The RAF deployed four TriStars during Operation Telic, to an as-yet-undisclosed location.

Orbital Sciences' L-1011-100 "Stargazer" releases Pegasus rocket.

The TriStar is expected to remain in service with the RAF until the end of this decade, when it is scheduled to be replaced by the Airbus A330 MRTT under the Future Strategic Tanker Aircraft (FSTA) program. The Airtanker consortium, led by EADS, won the FSTA contract in January 2004. However beginning in April 2004 there have been continuing rumors about the fragile state of the contract negotiations. This culminated in an ultimatum by the UK's Defence Procurement Agency, delivered to EADS, demanding a reduced price for the aircraft. With continuing doubts over the FSTA program Marshall Aerospace, responsible for the conversion of the RAF's original TriStars, have offered to buy and convert some of the large number of surplus commercial TriStars. This would give the UK a much needed increase in capacity (with the upcoming retirement of the VC-10 fleet) at a fraction of the cost of the £13Bn FSTA project.

The TriStar's second largest operator, ATA Airlines, uses the type exclusively on military charters for the U.S. Armed Forces.

In the early 1990s, Orbital Sciences began to use a converted L-1011-100 named Stargazer to launch Pegasus rockets into orbit around Earth. This venture effectively rendered the small Scout rocket obsolete. This aircraft was also used in support of the X-34 program. NASA performed aerodynamic research on Orbital Science's L-1011 in 1995.

Variants

L-1011-1

The L-1011-1 was the first production model of the L-1011, designed for short and medium-range flights. This type was purchased by Air Canada, ANA, Cathay Pacific, Eastern and other operators with regional trunk routes requiring a widebody aircraft. Pacific Southwest Airlines purchased two L-1011-1 models with lower deck seating. This variant was also the only wide-body ever to have the option for a full-height built-in airstair incorporated into the design, although it remained an option on other variants.

L-1011-50

The L-1011-50 was an upgraded version of the L-1011-1 with an increase in maximum takeoff weight from 430,000 lb (195,050 kg) to either 440,000 lb (199,580 kg) or 450,000 lb (204,120 kg). Fuel capacity was not increased. The L-1011-50 was only available as a conversion package for the L-1011-1 and was never built new.

L-1011-100

The L-1011-100 first flew in 1975 and featured a new center fuel tank that increased the aircraft's range by nearly 930 miles (1,500 km). It was purchased by several airlines with longer-range routes, such as TWA, Air Canada and BEA.

L-1011-150

The L-1011-150 was a development of the L-1011-1 with maximum takeoff weight increased to 470,000 lb (213,190 kg). It was only available as a conversion for the L-1011-1.

L-1011-200

The L-1011-200 was introduced in 1976. Although otherwise similar to the -100 model, the -200 uses Rolls-Royce RB.211-524B engines to improve its performance in hot and high-altitude conditions. Gulf Air used -200 models to replace its aging Vickers VC-10 fleet.

L-1011-250

The L-1011-250 was an upgrade developed for late-model L-1011-1 aircraft and all L-1011-100 and L-1011-200 aircraft. It increased maximum takeoff weight to 510,000 lb (231,340 kg) and fuel capacity from 23,600 US gallons (89,335 liters) to 31,632 US gal (119,735 L). This variant also used the upgraded RB211-524B4I engine which could be easily upgraded on the existing RB211-524B powerplants of the L-1011-200 but required a re-engining on the L-1011-1 and L-1011-100 which used the original RB211-22B. The upgrade allowed the L-1011 to match the performance of the long-range McDonnell Douglas DC-10-30. Although it was applicable to all L-1011 models, it was only used by Delta Air Lines on six late-model L-1011-1 aircraft.

L-1011-500

The L-1011-500 was a longer-range variant first flight tested in 1978. Its fuselage length was shortened by 14 feet (4.3 m) to accommodate higher fuel loads. It also utilizes the more powerful engines of the -200 series. The -500 variant was popular among international operators and formed a significant portion of the L-1011 fleet of Delta and British Airways.

Specifications

Orthographically projected diagram of the Lockheed L-1011.

	L1011-1	L1011-200	L1011-500
Cockpit crew	Three
Seating capacity	253 (3-class)	263	234 (3-class)
Length	177 ft 8 in (54.2 m)	177 ft 8 in (54.2 m)	164 ft 2 in (50 m)
Wingspan	155 ft 4 in (47.3 m)	155 ft 4 in (47.3 m)	164 ft 4 in (50.1 m)
Tailspan	71 ft 7 in (21.8 m)
Height	55 ft 4 in (16.7 m )
Wing area	3456 ft² (321.1 m²)	3456 ft² (321.1 m²)	3541 ft² (329.0 m²)
Empty Weight	224,579 lb (101,867 kg)	231,600 lb (105,052 kg)	232,749 lb (105,573 kg)
Maximum take-off weight	430,000 lb (195,000 kg)	466,000 lb (209,000 kg)	496,000 lb (225,000 kg)
Max speed	.95 Mach
Cruising speed	.90 Mach
Range fully loaded	4,610 mi (7,419 km)	4,610 mi (7,419 km)	6,340 mi (10,200 km)
Service Ceiling	35,000 ft (10,670 m)	36,000 ft (10,970 m)	41,000 ft (12,496 m)
Engines (3x)	Rolls-Royce RB.211-22	Rolls-Royce RB.211-524B

Deliveries

1985	1984	1983	1982	1981	1980	1979	1978	1977	1976	1975	1974	1973	1972	1971	1970	Total
3	5	5	13	28	24	14	8	12	16	24	41	39	17	0	1	250

Aircraft in service

This table shows the numbers of Lockheed L-1011 in service.

Airline	Number
Air Rum	2
Air Universal	2
Al Anwa	1
Almiron Aviation	1
ATA Airlines	4
Bismillah Airlines	1
EuroAtlantic Airways	1
Globe Jet Airlines	4
Hewa Bora Airways	1
International Air Services	3
Las Vegas Sands Company	2
Luzair	2
Orbital Sciences Corporation	1
Orient Air	3
Privilege Jet Airlines	1
Royal Air Force	9
Sky Gate International Aviation	4
Starjet	4
Thai Sky Airlines	1
Trans Atlantic Airlines	1
White	1
Total	49

Incidents

• The 1972 crash of Eastern Air Lines Flight 401 in the Everglades as a result of the flight crew's failure to monitor the flight instruments during a malfunction of the landing gear position indicator system was the subject of a Hollywood movie, The Ghost Of Flight 401.
• In August 1980, Saudia Flight 163 was destroyed by fire on the ground after making an emergency landing at Riyadh's International Airport due to fire in the rear of the aircraft. Delays in initiating the evacuation of the aircraft resulted in the deaths of all 287 passengers and 14 crew.
• In August 1985, Delta Air Lines Flight 191 crashed while approaching Dallas-Fort Worth International Airport in heavy wind shear conditions. The crash killed 8 of 11 crew members and 128 of the 152 passengers on board as well as one person on the ground.
• On July 30, 1992 TWA Flight 843 aborted take-off shortly after liftoff from JFK en route to San Francisco. The aircraft came to rest, upright and on fire, on grass-covered soil, about 290 feet to the left of the departure end of runway 13R. There were no fatalities among the 280 passengers on board, but there were 10 injuries during egress.

In popular culture

• The airplane used on the ABC television series Lost is a dismantled L-1011 formerly belonging to Eastern Airlines.
• El Ten Eleven is the name of an instrumental post-rock band formed in 2004 by Los Angeles-based musicians Kristian Dunn and Tim Fogarty. Their debut album, El Ten Eleven features a silhouetted trijet – however, it is a Boeing 727, not an L-1011.

Notes and references

• Yenne, Bill, Lockheed. Crescent Books, 1987.

External links

• L-1011 page on airliners.net
• L-1011 page on pbs.org
• Lockheed L-1011 Wing vortex study on NASA/DFRC site

Related content

Aircraft of comparable role, configuration, and era

• McDonnell Douglas DC-10
• Airbus A330-300
• Boeing 767-400ER

Related lists

• List of Lockheed aircraft
• List of airliners
• List of active United Kingdom military aircraft