An airstair is a set of steps built into an aircraft so that passengers may board and alight the aircraft. The stairs are built into a clamshell-style door on the aircraft. Airstairs eliminate the need for passengers to use a mobile stairway or jetway to board or exit the aircraft, providing more independence from ground services; some of the earliest aircraft to feature airstairs were the Martin 2-0-2 and Martin 4-0-4. Some models of the Douglas DC-3 were retrofitted with airstairs; as airport infrastructure has developed, the need for airstairs has decreased, as jetways or mobile stairways are available. Wide-body aircraft employ airstairs, as the doors are higher above the ground than narrow-body aircraft. One notable exception is the Lockheed L-1011, the only wide-body aircraft to feature full-height airstairs; the only other wide-bodies with airstairs, the VC-25 and the Ilyushin Il-86, have airstairs contained in the cargo hold, with steps inside the cabin to access these stairs. Some aircraft, like the Boeing 727 and McDonnell Douglas DC-9, were designed to improve ground services, with passengers deplaning from the front as the aircraft is serviced from the rear, enabling quicker turnarounds.
Airstairs are used as a security measure, for example on aircraft carrying the President of the United States, allowing the aircraft to be boarded by VIPs at any time - with or without the cooperation of ground services. Ventral airstairs are featured on most tail-engined airliners, such as the Boeing 727, the McDonnell Douglas DC-9, MD-80 and MD-90, the BAC 1-11, the Yakovlev Yak-40/Yak-42 series, are incorporated as ramps which lower from the fuselage; the Ilyushin Il-86 has three airstairs on the port side. The most common type of airstair is found in most business aircraft, regional jets, other small airliners, a stair built into the inside of the main passenger door, lowered to the outside. Aircraft such as the Fokker F-28 series and the VFW-Fokker 614 made this design popular; the stairs are part of the door rather than an attached stair. This design is efficient and because the aircraft which use it sit low to the ground, the design can stay simple and not add complexity or weight to the design, one of the biggest problems with airstair assemblies.
The design has been used with a single-length set of extension stairs on aircraft such as the cargo compartment of the widebody Ilyushin Il-86, Boeing VC-25, the belly lounges of three Lockheed L-1011s. Another widespread type of airstair is used for forward doors; the stair folds and stows under the floor of the door and is deployed from the fuselage below the forward door. This type of airstair is found on many short-range aircraft such as Boeing 737s, DC-9s, some Airbus A320 series aircraft; the mechanism is quite heavy. A unique airstair design was used for the aft doors of 737 Combi aircraft, which consisted of a clamshell door which dropped down to open much like a business aircraft, but had stairs which were stored trifold in the curve of the door, which would unfold to the ground; this system was cumbersome, was susceptible to damage, thus has been removed by many of its users. The most unusual airstair design was found on the Lockheed L-1011, a full-height airstair, stored in a cargo compartment and allowed access from the right aft passenger door to the ground.
This design was so large and heavy, it took up valuable cargo space, that it was used. The original On-Board Folding Airstairs were designed by Winters Aircraft Engineering Company over 30 years ago. Airweld Incorporated is the current STC holder and has FAA PMA for all of the original STC’s issued to Winters, as well as STC’s issued to subsequent manufactures including Kaiser Aerospace, WAPCO, Advanced Aerospace; the On-Board Folding Airstairs can be found in use on many U. S. and Foreign Military and Government Aircraft including the Boeing E4B as well as VIP aircraft around the world. The On-Board Folding Airstairs is a multi-section airstair that can be installed at either the forward, center, or aft doors; when retracted/closed, the airstair sits on a track and is stowed in a closet either Forward, Aft, or Transverse. A rear, airstair can be used as a safe means of parachuting from an airliner, equipped with one; this was attempted on 24 November 1971 by an unknown hijacker known as D. B.
Cooper, who jumped from a Boeing 727 along with US$200,000 in ransom money. However it is unknown. Subsequently, a number of individuals carried out copycat hijackings against Boeing 727s and safely parachuted to the ground, although all were apprehended by the authorities. To prevent this, Boeing 727s were ordered to be fitted with a simple device known as a Cooper vane that prevented the ventral airstair from being opened in flight. During the 2012 Boeing 727 crash experiment, a flight crew took off in the Boeing 727, to be crashed and flew it to a pre-selected desert site before safely parachuting from the ventral hatch, it was deliberately flown into the ground under remote control. Jet bridge Evacuation slide Period photographs of commercial airliners with lowered airstairs, from the Ed Coates collection: Douglas DC-3 of Southwest Airways Martin 2-0-2, Martin 4-0-4 of Pacific Air Lines The Airstair of Yakovlev Yak-42D Airliners.net
Southern Airways was an airline in the United States from its founding by Frank Hulse in 1949 until 1979 when it merged with North Central Airlines to become Republic Airlines, which on October 1, 1986, became part of Northwest Airlines, which merged into Delta Air Lines in 2008. Southern corporate headquarters was in Birmingham, with operations headquartered at William B. Hartsfield Airport, near Atlanta; as a local service airline, Southern Airways covered the south-central U. S. In 1955 their network spanned from Memphis south to New Orleans and east to Charlotte and Jacksonville. In August 1953 Southern flew to 29 airports and in August 1967 to 50. Like other Local Service airlines Southern was subsidized. In May 1968 Southern's routes extended from Tri-Cities in Tennessee south to New Orleans and Jacksonville, east from Baton Rouge and Monroe, Louisiana to the coast at Myrtle Beach and Charleston. In 1968 a route sprouted northward: three weekday Douglas DC-9-10s from Columbus GA nonstop to Washington Dulles and on to New York LaGuardia.
These originated at Eglin Air Force Base, FL. Like most local service airlines Southern flew only Douglas DC-3s for the first few years. In 1961 they began adding 22 40-passenger secondhand Martin 4-0-4s acquired from Eastern Air Lines, newer aircraft that were pressurised and had a rear ventral stairway; the last DC-3 flight was in 1967. Southern's first 65-75 passenger Douglas DC-9 series 10s arrived in 1967 followed by 85-95 passenger McDonnell Douglas DC-9 series 30s in 1969; the last scheduled flight by a Martin was on 20 April 1978 from Atlanta to Gadsden and back. Some DC-9s were bought new and some used. Both airlines had purchased these aircraft new from Douglas. Unlike other local service airlines Southern did not operate turboprops during the 1960s and 1970s, but by the time of the merger with North Central, Southern had replaced their Martin 4-0-4s with several 19-passenger Fairchild Swearingen Metroliner "Metro II"s. By 1971 Southern was flying south to Orlando and Miami. U. S. government regulation didn't allow Southern to fly nonstop from New York or Washington, D.
C. to Atlanta, so Southern had nonstops to Columbus, Georgia on to Dothan, Alabama. Many flights made six intermediate stops en route. With more DC-9s, many routes once served with prop aircraft were served with jets that linked small cities to Atlanta and Memphis: Columbus, Georgia to Washington, DC continuing to New York City. Meridian, Mississippi to Birmingham, Alabama. Tuscaloosa, Alabama to Atlanta and Columbus, Mississippi. Muscle Shoals/Florence, Alabama to Memphis and Huntsville/Decatur, Alabama with continuing eastbound service to Atlanta. Greenville, Mississippi to Memphis and Monroe, Louisiana with continuing southbound service to Baton Rouge and New Orleans. Columbia, South Carolina to Greenville/Spartanburg and Charleston, South Carolina. Albany, Georgia to Atlanta, Georgia. One DC-9-14 aircraft operated a "milk run" multi-stop routing from Miami to Orlando, Panama City, Eglin AFB, Gulfport, New Orleans, Atlanta, Memphis, St Louis and Chicago Midway. Time en route was 32 minutes. By the mid-1970s Southern's system had expanded to St. Louis, Detroit, Ft. Lauderdale and Grand Cayman in the Caribbean, Southern's only international destination.
Southern Airways called itself the "Route of the Aristocrats" and they used the slogan "Nobody's Second Class on Southern" in their television commercials. They were famous for their promotional shot glasses: for a time, differently designed shot glasses were issued each year. Original Southern shot. During the early 1970s before strict airport security was implemented across the United States, several airlines experienced hijackings. Southern Airways Flight 49, a DC-9 en route from Memphis to Miami was hijacked on November 10, 1972 during a stop in Birmingham, Alabama; the three hijackers boarded the plane armed with handguns and hand grenades. At gunpoint, the hijackers took the airplane, the plane’s crew of four, 27 passengers to nine American cities, to Havana, Cuba. During the long flight the hijackers threatened to crash the plane into the Oak Ridge, nuclear facilities, insisted on talking with President Richard Nixon, demanded a ransom of $10 million. Southern Airways was only able to come up with $2 million.
The pilot talked the hijackers into settling for the $2 million when the plane landed in Chattanooga for refueling. Upon landing in Havana the Cuban authorities arrested the hijackers and, after a brief delay, sent the plane and crew back to the United States; the hijackers and $2 million stayed in Cuba. Southern Airways accounted for the $2 million by debiting it to an account entitled "Hijacking Payment." This account was reported as a type of receivable under "other assets" on Southern's balance sheet. The company maintained that they would be able to collect the cash from the Cuban government and that, therefore, a receivable existed. Southern Airways was repaid $2 million by the Cuban government, attemptin
Colombia the Republic of Colombia, is a sovereign state situated in the northwest of South America, with territories in Central America. Colombia shares a border to the northwest with Panama, to the east with Venezuela and Brazil and to the south with Ecuador and Peru, it shares its maritime limits with Costa Rica, Honduras, Jamaica and the Dominican Republic. Colombia is a unitary, constitutional republic comprising thirty-two departments, with the capital in Bogota. Colombia has been inhabited by various indigenous peoples since 12,000 BCE, including the Muisca and the Tairona, along with the Inca Empire that expanded to the southwest of the country; the Spanish arrived in 1499 and by the mid-16th century conquered and colonized much of the region, establishing the New Kingdom of Granada, with Santafé de Bogotá as its capital. Independence from Spain was achieved in 1819, but by 1830 the "Gran Colombia" Federation was dissolved, with what is now Colombia and Panama emerging as the Republic of New Granada.
The new nation experimented with federalism as the Granadine Confederation, the United States of Colombia, before the Republic of Colombia was declared in 1886. Panama seceded in 1903. Beginning in the 1960s, the country suffered from an asymmetric low-intensity armed conflict and rampant political violence, both of which escalated in the 1990s. Since 2005, there has been significant improvement in security and rule of law. Colombia is one of the most ethnically and linguistically diverse countries in the world, with its rich cultural heritage reflecting influences by indigenous peoples, European settlement, forced African migration, immigration from Europe and the Middle East. Urban centres are located in the highlands of the Andes mountains and the Caribbean coast. Colombia is among the world's 17 megadiverse countries, the most densely biodiverse per square kilometer. Colombia is a middle power and regional actor in Latin America, it is part of the CIVETS group of six leading emerging markets and a member of the UN, the WTO, the OAS, the Pacific Alliance, other international organizations.
Colombia's diversified economy is the fourth largest in Latin America, with macroeconomic stability and favorable long-term growth prospects. The name "Colombia" is derived from the last name of Christopher Columbus, it was conceived by the Venezuelan revolutionary Francisco de Miranda as a reference to all the New World, but to those portions under Spanish rule. The name was adopted by the Republic of Colombia of 1819, formed from the territories of the old Viceroyalty of New Granada; when Venezuela and Cundinamarca came to exist as independent states, the former Department of Cundinamarca adopted the name "Republic of New Granada". New Granada changed its name in 1858 to the Granadine Confederation. In 1863 the name was again changed, this time to United States of Colombia, before adopting its present name – the Republic of Colombia – in 1886. To refer to this country, the Colombian government uses the terms Colombia and República de Colombia. Owing to its location, the present territory of Colombia was a corridor of early human migration from Mesoamerica and the Caribbean to the Andes and Amazon basin.
The oldest archaeological finds are from the Pubenza and El Totumo sites in the Magdalena Valley 100 kilometres southwest of Bogotá. These sites date from the Paleoindian period. At Puerto Hormiga and other sites, traces from the Archaic Period have been found. Vestiges indicate that there was early occupation in the regions of El Abra and Tequendama in Cundinamarca; the oldest pottery discovered in the Americas, found at San Jacinto, dates to 5000–4000 BCE. Indigenous people inhabited the territory, now Colombia by 12,500 BCE. Nomadic hunter-gatherer tribes at the El Abra, Tibitó and Tequendama sites near present-day Bogotá traded with one another and with other cultures from the Magdalena River Valley. Between 5000 and 1000 BCE, hunter-gatherer tribes transitioned to agrarian societies. Beginning in the 1st millennium BCE, groups of Amerindians including the Muisca, Zenú, Tairona developed the political system of cacicazgos with a pyramidal structure of power headed by caciques; the Muisca inhabited the area of what is now the Departments of Boyacá and Cundinamarca high plateau where they formed the Muisca Confederation.
They farmed maize, potato and cotton, traded gold, blankets, ceramic handicrafts and rock salt with neighboring nations. The Tairona inhabited northern Colombia in the isolated mountain range of Sierra Nevada de Santa Marta; the Quimbaya inhabited regions of the Cauca River Valley between the Western and Central Ranges of the Colombian Andes. Most of the Amerindians practiced agriculture and the social structure of each indigenous community was different; some groups of indigenous people such as the Caribs lived in a state of permanent war, but others had less bellicose attitudes. The Incas expanded their empire onto the southwest part of the country. Alonso de Ojeda reached the Guajira Peninsula in 1499. Spanish explorers, led by Rodrigo de Bastidas, made the first exploration
Air Florida was an American low-cost carrier that operated from 1971 to 1984. In 1975 it was headquartered in the Dadeland Towers in what is now Kendall, Florida in unincorporated Miami-Dade County, Florida. Air Florida was based at Miami International Airport, it was founded in September 1971 by a Miami, native, Eli Timoner, was organized by company president Ted Griffin, a former marketing director of Eastern Airlines. It initiated revenue operations on September 28, 1972, operating as an intrastate airline using two Boeing 707 jetliners purchased from Pan American World Airways and offering twice-daily service in Florida between Miami, Orlando and St. Petersburg on a "triangle" routings of MIA-MCO-PIE-MIA and MIA-PIE-MCO-MIA with a one way introductory fare of $12.00. The airline acquired Lockheed L-188 Electra turboprop aircraft which replaced the Boeing 707s. Although Air Florida began operations as an intrastate air carrier flying wholly within the state of Florida, it subsequently began adding domestic and international destinations outside of the state.
With this expansion, Air Florida's fleet grew to include Boeing 727-200, Boeing 737-100, Boeing 737-200, Douglas DC-8-62, Douglas DC-9-10, McDonnell Douglas DC-10-30 jetliners. Ed Acker CEO of Braniff International Airways, led an acquisition of Air Florida in 1975 and expanded the airline into the interstate market following the Airline Deregulation Act of 1978. In addition to Air Florida having a large presence in the Northeast-to-Florida market during the 1970s and 1980s, the airline expanded internationally and served various points in the Caribbean and Central America, as well as a number of European destinations including Amsterdam, Brussels, Düsseldorf, London, Madrid and Zurich; the European services were flown with McDonnell Douglas DC-10-30 aircraft, although British Island Airways provided connecting passenger service with their British Aircraft Corporation BAC One-Eleven jets for Air Florida on some intra-European route segments with an example being London-Amsterdam. The airline operated a leased Douglas DC-8-62 for use on transatlantic flights at one point.
Air Florida was well known for its attractive flight attendants and, on international flights, four-star cuisine. In 1981, shortly before the crash of Air Florida Flight 90, Acker left Air Florida to become the Chairman, CEO and President of Pan American World Airways. Air Florida tried to buy out Western Airlines during the 1980s in order to increase its presence in the West and begin proposed flights to Mexico and western Canada; the negotiations with Western ended up with Air Florida owning 16 percent of the California-based company. Western was acquired by and merged into Delta Air Lines; the crash of Flight 90 on January 13, 1982, coupled with Air Florida's high financial leverage and reliance on foreign currency trading for profits, led the company to declare bankruptcy and cease operations on July 3, 1984, despite an effort by new head Donald Lloyd-Jones to save the company. When operations ceased, Air Florida had over 18 months of unprocessed credit card ticket purchases and dozens of flight crews idle at home because management had failed to renew leases on all DC-10-30 aircraft.
Midway Airlines acquired most of the assets of Air Florida for $53 million while Air Florida was in Chapter 11 bankruptcy protection. Air Florida Commuter was not an airline, but a system of affiliated commuter and regional air carriers that fed traffic into Air Florida's hubs. In an arrangement known as code-sharing, each airline painted their aircraft in Air Florida colors and their flights were listed in reservations systems as Air Florida flights. Air Miami became the first affiliate in 1980 and over a dozen other airlines became part of the system, including: Marco Island Airways, Florida Airlines, Key Air, Southern International, Skyway Airlines, North American Airlines, National Commuter Airlines, Gull Air, Finair, Atlantic Gulf, Skyway of Ocala and others; as Air Florida became financially strapped, the commuter system was dismantled in early 1984. Air Florida sponsored Southampton Football Club, an English Football League side, during the 1983-84 season, in which Southampton were league runners-up.
The deal was cancelled after one season due to Air Florida's insolvency. When Air Florida ceased all operations, the airline was operating the following mainline jet aircraft: Air Florida operated the following aircraft in its mainline fleet, but retired these types before the demise of the airline: Boeing 707 Boeing 727-100 Boeing 727-200 British Aircraft Corporation BAC One-Eleven Lockheed L-188C Electra The commuter and regional affiliates of Air Florida operated the following prop and turboprop aircraft: Beechcraft 99 Britten-Norman Islander Britten-Norman Trislander CASA 212-200 Cessna 208B Grand Caravan Cessna 340 Cessna 402 Convair 580 de Havilland Canada DHC-6 Twin Otter de Havilland Heron Embraer EMB-110 Bandeirante Martin 4-0-4 Mohawk 298 Nord 262 Piper Navajo Some of the above destinations in the U. S. and the Bahamas were served by commuter air carriers operating Air Florida Commuter service with prop and turboprop aircraft via respective code sharing agreements. Air Florida served Charleston, South Carolina.
Glenn L. Martin
Glenn Luther Martin was an early American aviation pioneer. He designed and built his own aircraft and was an active pilot, as well as an aviation record-holder, he founded an aircraft company in 1912 which through several mergers amalgamated into what is today known as Lockheed Martin. Glenn L. Martin was born in Iowa, on January 17, 1886 to Minta and Clarence Martin. At the age of two, Martin's family moved to Salina, Kansas, so that his father could run a wheat farm. By age six, he at first his friends made fun of box-kites he built; when the kites flew well, people paid him twenty-five cents to build one for them. He turned his mother's kitchen into a "factory" to produce more kites. Martin began using sails on everything from ice skates to wagons, his bicycle to move faster with less effort, he studied business at Kansas Wesleyan in Salina, Kansas. In 1933, he received an honorary Bachelor of Science degree from Kansas Wesleyan University; as he grew up, he became fascinated with flight, first with kites later the Wright brothers' airplane.
In 1909 he decided to build one himself based on the Curtiss June Bug, but it was destroyed on the first test flight. For his next effort, Martin used bamboo in the aircraft's construction; this airplane made a short flight. Martin was assisted by his mother Minta Martin holding a lamp in the building of his first few airplanes. On May 10, 1912, Martin flew a self-built seaplane from Newport Bay, California to Avalon on Catalina Island back across the channel; this broke the earlier English Channel record for over-water flight. Martin's total distance was 68 miles, with the Newport-Avalon leg taking 37 minutes, he picked up a bag of mail on the island on the way, was presented with $100 prize for his achievement. In 1913, Martin was not as fortunate while competing in the Great Lakes Reliability Cruise, a 900 miles race of seaplanes around the Great Lakes. Martin's pontoon hit a wave at high speed and low altitude, causing the plane to somersault, sink to the bottom with Martin, who escaped and attempted to salvage the plane to finish the race.
In 1912, Martin built an airplane factory in an old Methodist church in California. To make money to finance this business, he began stunt-flying at local airfields, he saw an advertisement for a pilot/airplane owner to play a role in a movie. Sensing an opportunity to market his airplanes, he got the part, he was to play the role of a dashing hero in the movie A Girl of Yesterday starring Mary Pickford. He soon found. In addition to flying Pickford around in his airplane, he had a scene where he had to kiss Frances Marion, who became a legendary Hollywood screenwriter. Martin in describing his hesitance having to kiss Marion declared "my mother would not like it" which astounded Pickford, he worked up the courage however after persuasion by Paramount boss Adolph Zukor and completed the scene. Martin held a record for longest American over-water flight, 66 miles, his company designed aircraft including bombers for both world wars. An early success came during World War I with production of the MB-1 bomber.
The MB-2 and others were successful. In 1932, Martin won the Collier Trophy for his involvement with the Martin B-10 bomber, he founded the Glenn L. Martin Company in 1912. In 1916 he merged his company with the original Wright Company, forming the Wright-Martin Aircraft Company, he soon left and founded a second Glenn L. Martin Company in 1917; that company merged with the American-Marietta Corporation in 1961, becoming the Martin Marietta Corporation. This company merged with the Lockheed Corporation in 1995, forming Lockheed Martin, a major U. S. aerospace and defense contractor. In the 1940s, towards the end of Martin's life, he and his beloved and now aged mother Minta were photographed touring the Martin facilities in Baltimore and celebrating Martin's success as one of the captains in the aviation industry. In 1925, the Industrial Bureau contacted Glenn Martin at his plant in Ohio, it was the Bureau's job to attract Martin to Maryland. After speaking with Martin, a site in Middle River was chosen.
From this point it was a three-year-long struggle to acquire the land needed from forty-five property owners. This struggle involved convincing the citizens that this was going to become a booming industry and would provide many jobs in the area. In 1928, the Glenn L. Martin Company moved to Maryland, bringing hundreds of much needed jobs, an airport, a booming aviation industry, he died from complications of a stroke on December 5, 1955, in Maryland. Martin's donations to the University of Maryland, College Park, created the Glenn L. Martin Institute of Technology, which includes the A. James Clark School of Engineering; the University's wind tunnel and a classroom building bear Martin's name. The Glenn L. Martin Stadium on the campus of Kansas Wesleyan University opened in 1940. In 1977, Martin was inducted into the International Space Hall of Fame. Notes BibliographyGlenn Martin flies to Avalon to celebrate a 25-year-old record. LIFE May 10, 1937. Pg 30 From Barnstorming to Bombers. Popular Science Sep 1941.
Pg 51PatentsU. S. Patent D134,875, Design for a lapel pin or the like U. S. Patent 1,165,891, Packed parachute U. S. Patent 2,411,382, Docking flying boats U. S. Patent 2,147,795, Aircraft construction Martin's biography at the GLM Maryland Aviation Museum Kites to Bombers Glenn L. Martin at Find a Grave
Fairchild Swearingen Metroliner
The Fairchild Swearingen Metroliner is a 19-seat, twin-turboprop airliner first produced by Swearingen Aircraft and by Fairchild Aircraft at a plant in San Antonio, United States. The Metroliner was an evolution of the Swearingen Merlin turboprop-powered business aircraft. Ed Swearingen, a Texas fixed-base operator, started the developments that led to the Metro through gradual modifications to the Beechcraft Twin Bonanza and Queen Air business aircraft, which he dubbed Excalibur. A new fuselage and vertical fin were developed, married to salvaged and rebuilt Queen Air wings and horizontal tails, Twin Bonanza landing gear. Through successive models the engines were changed to Pratt & Whitney Canada PT6 Garrett TPE331 turboprops; these were marketed as business aircraft seating eight to ten passengers. An all-new aircraft was built and named the SA226-T Merlin III with a new nose, landing gear, cruciform horizontal tail and inverted inlet Garrett engines. A stretch of the Merlin III was designed, sized to seat 22 passengers and called the SA226-TC Metro.
Because FAA regulations limited an airliner to no more than 19 seats if no flight attendant was to be carried, the aircraft was optimized for that number of passengers. The standard engines offered were two TPE331-3UW turboprops driving three-bladed propellers. A corporate version called the SA226-AT Merlin IVA was marketed and sales of this version were double that of the Metro. Prototype construction of the Metro began in 1968 and the first flight was on August 26, 1969. Swearingen Aircraft encountered financial difficulties at this stage, late in 1971 Fairchild, bought 90% of Swearingen and the company was renamed Swearingen Aviation Corporation, it was at this point that the cash-strapped company was able to put the Metro into production. In 1974, the original Metro models were replaced by the SA226-TC Metro II after about 20 Metros and about 30 Merlin IVAs had been built. Among the changes made were larger, squared-oval windows and optional provision for a small Rocket-Assisted Take Off rocket in the tail cone, this being offered to improve takeoff performance out of "hot & high" airfields in the event of an engine failure.
The Metro and Metro II were limited to a maximum weight of 12,500 pounds in the US and countries using imperial units, 5,700 kg in countries using SI units. When this restriction was lifted the Metro II was re-certified as the Metro IIA in 1980 with a maximum weight of 13,100 pounds and the Metro II's TPE331-3 engines replaced by -10 engines of increased power; the SA227-AC Metro III followed initially certified in 1980 for up to 14,000 pounds, this increasing to 14,500 pounds as engines and structures were upgraded. An option to go as high as 16,000 pounds was offered. Externally, improvements incorporated into the Metro III were a 10 ft increase in wing span, four-bladed props, redesigned "quick-access" engine cowlings and numerous drag-reducing airframe modifications, including landing gear doors that closed after the gear was extended. Once again a corporate version was offered as the Merlin IVC. A version with strengthened floors and the high gross weight option was offered as a cargo aircraft known as the Expediter.
Both the Expediter and the Merlin IVC were designated the SA227-AT. Due to reliability problems with Garrett engines in the second half of the 1980s, the Metro IIIA was offered with two Pratt & Whitney Canada PT6A-45R turboprops in place of the Garrett units. A special model was the SA227-BC Metro III built for Mexican airline AeroLitoral, which took delivery of 15 of the 18 of this model that were produced. Improvements beyond the Metro III provided better systems, more power and a further increase in takeoff weight; this design effort resulted in the SA227 CC and SA227-DC models called the Metro IV renamed Metro 23, so named as they were designed for certification under FAR Part 23 standards. A Metro 23 EF with an external pod under the lower fuselage for greater baggage capacity was offered as well as an Expediter 23 and Merlin 23; the SA227-CC was an interim model with TPE331-11U engines and only a handful were built. In the 1960s Swearingen Aircraft developed a prototype SA-28T eight-seat jet aircraft with a flapless delta wing.
It shared the cockpit with the Merlin/Metro. The two engines were to be Garrett TFE731 turbofans in development. Early flights were to be undertaken with General Electric CJ610 engines fitted. Development continued after Fairchild acquired the company, but the project was shut down nine weeks from first flight, it was cut up as scrap and the fuselage used as a Metro display at trade shows. At the 1987 Paris Air Show, Fairchild released details of proposed developments of the Metro designated the Metro V and Metro VI; these versions would have featured a longer fuselage with a taller "stand-up" cabin providing 69 in of interior height for passengers. A Merlin V corporate version of the Metro V was plan
Piedmont Airlines, Inc. is an American regional airline operating for American Eagle US Airways Express. It is a wholly owned subsidiary of the American Airlines Group, headquartered in unincorporated Wicomico County, near the city of Salisbury, it conducts flight operations using Embraer ERJ 145 aircraft. Piedmont Airlines, Inc. provides ground handling and customer service for airports in the Northeastern & Western parts of the United States. Its main base is Philadelphia International Airport with an additional hub at Charlotte Douglas International Airport; the airline was formed in 1961 by Richard A. Henson as Henson Aviation, a fixed-base operator in Hagerstown, Maryland, it began its first scheduled flights to Washington National Airport in 1962 under the Hagerstown Commuter name changed to Henson Airlines. Allegheny Airlines and Henson began one of the world's first code sharing arrangements in 1967. Henson re-branded itself as an Allegheny Commuter carrier using Beechcraft 99 aircraft.
It developed a route structure serving Washington D. C. Philadelphia and Baltimore, while establishing a new headquarters for Allegheny Commuter at Salisbury, Maryland in 1968. In the 1970s, the airline upgraded to Short de Havilland Canada DHC-7 Dash 7 turboprops. In 1983, Piedmont Aviation bought Henson and re-branded the airline as "Henson, The Piedmont Regional Airline." Under Piedmont's control, the airline expanded particularly in Florida. Both were purchased by the USAir Group in 1987 with Piedmont absorbed two years and Henson's aircraft repainted in USAir Express livery; the 1980s saw rapid growth by the company with the upgrade of its fleet to the de Havilland Canada Dash 8 aircraft and fleet expansion. With the growth in capacity, the airline expanded to Florida, including numerous intrastate routes in Florida, it opened a maintenance facility in Jacksonville; the Piedmont name was resurrected in 1993, when USAir renamed Henson to "Piedmont Airlines", to protect the Piedmont brand name, which could be used by others if not exercised in trade use for a period of time.
USAir continued this practice by changing the name of its two other wholly owned regional airline subsidiaries and Suburban Airlines, to PSA Airlines and Allegheny Airlines, respectively. In 1997, USAir was renamed US Airways, Piedmont and Allegheny were re-branded as US Airways Express carriers. US Airways merged Allegheny Airlines into Piedmont in 2004; the airline had more than 7,000 employees, as of December 2017. As of December 2017, the airline operated 400 daily flights to more than 55 destinations; as of August 2018, Piedmont is the exclusive operator at Williamsport Regional Airport, Salisbury Regional Airport. Piedmont Airlines flies under the American Eagle brand, after a merger of American Airlines and US Airways in December 2013. Piedmont has crew bases in two locations: Charlotte Douglas International Airport Philadelphia International Airport As of March 2019 the Piedmont Airlines fleet consists of the following aircraft. On September 23, 1985, Henson Airlines Flight 1517, a Beechcraft B99 Airliner 15-passenger turboprop airplane, crashed near Grottoes, Virginia.
The crash was fatal to all both crewmembers. S. pilot, First Officer Zilda A. Spadaro-Wolan; the National Transportation Safety Board concluded that part of the probable cause of the crash was the airline's failure to standardize the cockpit configurations of its aircraft and on its failure to provide adequate training to its pilots. On November 16, 2008, Flight 4551, a US Airways Express de Havilland Dash-8 turboprop operated by Piedmont Airlines, took off from Lehigh Valley International Airport at 8:20am heading to Philadelphia International Airport, had to make an emergency landing; the flight crew was indicated that the front nose gear hadn't come down and had to make a flyover the runway for confirmation. Of 35 passengers and 3 crew, there were no injuries; the aircraft was returned to service shortly thereafter. On January 1, 2011, US Airways Express Flight 4352, a Piedmont Airlines-operated de Havilland Dash-8 turboprop forced an evacuation of the U. S. Capitol and fighter jets were scrambled from Andrews Air Force Base after Flight 4352 suffered radio problems on approach to Washington, DC's Ronald Reagan Washington National Airport and strayed into restricted airspace.
The Capitol was evacuated for 20 minutes until the Dash-8 aircraft landed at Reagan National Airport. On January 7, 2011, a Bombardier Dash 8-100, operating as Piedmont Airlines Flight 4507 under US Airways Express from Philadelphia International Airport to Tweed New Haven Regional Airport in Connecticut was struck by lightning over the Long Island Sound; the captain reported electrical problems and diverted safely to Long Island Macarthur Airport due to more favorable weather conditions. The aircraft had 33 passengers aboard who were bussed to New Haven. On May 18, 2013, US Airways Express Flight 4560 made a belly landing at Newark Liberty International Airport after landing gear would not extend. All passengers and crew members were evacuated safely; the airline began sponsoring NASCAR as the primary sponsor for Ricky Rudd and Richard Childress Racing in 1982. They won a championship as the primary sponsor for Terry Labonte in 1984. Air transportation in the United States List of airlines of the United States List of airports in the United States Transportation in