Design and developmentEditIn the 1960s, American Airlines approached Lockheed and competitor Douglas (later McDonnell 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 early in its career due to wing vibration. 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 "jumbo twin", but a three-engine design was ultimately chosen to give the plane enough thrust to take off from existing runways.
The design featured a twin-aisle interior with a maximum of 400 passengers, a three-engine layout, low noise emissions (in the early 1970s, Eastern Air Lines nicknamed the L-1011 "The WhisperLiner"), improved reliability, and efficient operation. The main visible difference between the TriStar and the DC-10 that emerged at Douglas 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 that of the Boeing 727) for improved quietness and stability. A major differentiator between the L-1011 and the DC-10 was Lockheed's selection of the Rolls-Royce RB211 engine for the L-1011. As originally designed, the RB211 turbofan was an advanced three-spool design with a carbon fibre fan, which would have better efficiency and power-to-weight ratio than any competing design. This would make the L-1011 more efficient, a major selling point.
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 power plant development. In February 1971, after massive development costs associated with the RB211, Rolls-Royce went into receivership. 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 the U.S. government guarantee the bank loans 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. For the rest of the RB211 project, Rolls remained a government-owned company.
Manufactured in Lockheed facilities in Burbank and Palmdale, California, the TriStar faced brisk competition with the 747 and, even more directly, the DC-10, which it closely resembled. 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.Template:Fact However, 446 DC-10s were sold compared to 250 TriStars, 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 that 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 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, whereas the later 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, using four redundant hydraulic systems; 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 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.
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) operated three L1011-500s prior to the company's shut-down in April 2008.
The two L-1011 aircraft delivered to PSA were configured with internal airstair doors that led into an entry hall in what was normally the forward lower baggage hold. This was intended to allow operations from airfields in Latin America that did not have terminal buildings with Jetway type gates. These two aircraft were later in service with Aeroperú and Worldways Canada.
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.
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. All of the aircraft serve with No. 216 Squadron, and are based at RAF Brize Norton. 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 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.
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 -50 was available only as a conversion package for the L-1011-1 and was never built new.
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.
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 available only as a conversion for the L-1011-1.
The L-1011-200 was introduced in 1976. Although otherwise similar to the -100, 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 uneconomical Vickers VC-10 fleet.
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 liters). 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.
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.
Aircraft in serviceEdit
This table shows the numbers of Lockheed L-1011 in service (10 October 2008)Template:Fact
|Las Vegas Sands Corporation||1|
|Orbital Sciences Corporation||1|
|Royal Air Force||9|
Incidents and accidentsEdit
- Notable incidents and accidents
- 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 2 Hollywood movies, Crash and The Ghost Of Flight 401.
- In August 1980, a fire destroyed the L-1011 used for Saudia Flight 163 on the ground after the pilots made 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.
- On December 23, 1980, Saudi Arabian Airlines Flight SV162, a tire on L-1011 exploded, penetrating the passenger cabin. The plane lost cabin pressure and two passengers fell out of the plane.
- On May 27, 1985, an L-1011 overran the runway at Leeds Bradford International Airport after a flight from Palma De Mallorca in bad weather. The plane suffered serious damage to its fuselage and undercarriage but only minor injuries were reported. The aircraft was repaired and remained in service for another 14 years. The crash resulted from the aircraft landing just past the old runway threshold, which was a different color from the recently laid extension to the runway.Template:Fact
- In August 1985, Delta Air Lines Flight 191 crashed while approaching Dallas-Fort Worth International Airport in micro burst 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 May 3, 1986 an Air Lanka Flight UL512 TriStar was destroyed on the ground in Colombo, Sri Lanka, after a bomb exploded in the rear cargo hold severing the tail and killing 21 people.
- 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 minor injuries during egress. The L-1011 was destroyed in the fire.
|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 (50m)
|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 (231,332 kg)|
|Max speed||Mach 0.95|
|Cruising speed||Mach 0.90|
|Range fully loaded||4,610 mi (7,419 km)||4,610 mi (7,419 km)||6,340 mi (11,900 km)|
|Service Ceiling||35,000 ft (10,670 m)||36,000 ft (10,970 m)||43,000 ft (12,496 m)|
|Engines (3x)||Rolls-Royce RB.211-22||Rolls-Royce RB.211-524B|
In popular cultureEdit
The airplane used on the ABC television series Lost is a dismantled L-1011 formerly belonging to Eastern Airlines and later Delta Air Lines. Post-rock band El Ten Eleven derives its name from the aircraft.Template:Fact
- ↑ 1.0 1.1 Template:Citation/core
- ↑ PBS - Chasing the Sun - Lockheed L-1011
- ↑ Boyne, Walter J., Beyond the Horizons: The Lockheed Story. St. Martin's Press: New York, 1998, p. 354.
- ↑ It did this because, if Lockheed (which was itself weakened by the difficulties) had failed, the market for the RB211 would have evaporated.
- ↑ Template:Citation/core
- ↑ Template:Citation/core
- ↑ Tristar used to launch Pegasus
- ↑ Orbital Sciences Corporation L-1011, Stargazer carries HESSI spacecraft from Vandenberg AFB to the Kennedy Space Center, February 1, 2002
- ↑ NASA Dryden L-1011 Tristar Photo Collection
- ↑ US Airways History
- ↑ Luzair.com "Fleet" page. Accessed June 22, 2008.
- ↑ Lockheed L-1011 Tristar incidents, Aviation-Safety.net, 13 August 2008.
- ↑ Lockheed L-1011 Tristar hull-losses, Aviation-Safety.net, 13 August 2008.
- ↑ Lockheed L-1011 Tristar Statistics, Aviation-Safety.net, 3 December 2007.
- ↑ AirDistaster.com #12231980
- ↑ Aircraft Accident Report, Trans World Airlines Flight 843, NTSB, 31 March 1993.
- ↑ The "Lost" airplane made 28,822 flights before its "crash"
- Yenne, Bill, Lockheed. Crescent Books, 1987.
- L-1011 page on pbs.org
- L-1011 page on airliners.net
- Lockheed L-1011 Wing vortex study on NASA/DFRC site
- NMedia.com L1011 Tribute video
- Pan Am L-1011-500 Clipper Aircraft Names by FAA Registry Number