The ATR-72 is a stretched development of the popular ATR-42 and was launched in January 1986.

The first of three ATR-72 development aircraft flew for the first time on October 27 1988, followed by the awarding of French and then US certification in late 1989. Entry into service was on October 27 1989 with Kar Air of Finland. Some other early operators are Foshing Airlines, NFD (later Eurowings), CSA, American Eagle, TAT, Air Littoral, LOT, and Olympic Aviation.

Significant differences between the ATR-72 and the smaller and older ATR-42 include a 4.50m (14ft 9in) fuselage stretch and reworked wings. The ATR-72's wings are new outboard of the engine nacelles and with 30% of it made up of composite materials, comprising composite spars and skin panels and a carbon fibre wing box.

Aside from the baseline ATR-72-200, two developments have been offered, the ATR-72-210, and the ATR-72-500 (previously ATR-72-210A). The ATR-72-210 is optimised for operations in hot and high conditions. It has more powerful PW-127 engines for better takeoff performance.

The ATR-72-500 (renamed from ATR-72-210A on May 18, 1998) further improved hot and high model was certificated in early 1997. It features PW-127Fs driving six blade composite Hamilton Sundstrand propellers.

The ATR-52C is an as yet unlaunched derivative with a redesigned tail to incorporate a rear loading ramp, intended for military and commercial operators. As with the ATR-42, a military maritime patrol version, known as the Petrel 72, has also been offered.

The ATR-72 would have formed the basis for the ATR-82, a 78 seat stretched development. The ATR-82 would have been powered by two Allison AE-2100 turboprops (ATR studied turbofans for a time) and would have a cruising speed as high as 610km/h (330kt). The ATR-82 was suspended when AI(R) was formed in early 1996

The Beechcraft Baron is a light-medium twin-engine piston aircraft originally developed by Beech Aircraft Corporation and currently manufactured by the Beechcraft Division of Raytheon Aircraft. The Baron is a variant of the Beechcraft Bonanza, and was first introduced in 1961. Oddly, Beech also offered a Twin Bonanza line of airplanes which featured some design commonality with the Bonanza but in all respects were entirely different airplanes and could not be considered to be true "twin bonanzas".

As of 2006, a new Baron costs over $1.2 million. Since its inception, the Baron has always been near the top of the light airplane hierarchy. Expensive as it is to buy and to operate, the 'next step up' from a Baron is a very big one. Faster aircraft, with greater range and more load-carrying capability are generally turbine-powered and far more expensive.

Barons come in two basic types: the Baron 55 (short body) and Baron 58 (long body), with several subtypes.

Introduced in 1970, the more powerful Baron 58 has club seating, double aft doors, and a gross weight of 5400–5500 lb (2450–2500 kg), and is fitted with either the Continental IO520 or IO550 300 hp (224 kW) engine. The Baron 58 can cruise at 200 knots (370 km/h) at 7000 ft (2100 m), and is equipped with either 166 or 190 US gallon (628 or 719 L) fuel tanks.

In 1976, the turbocharged Baron 58TC and pressurized Baron 58P were introduced. These variants were powered by Continental TIO520 turbocharged engines of 310–325 hp (230–240 kW) and had an increased 6100–6200 lb (about 2800 kg) gross weight, and were certified under FAR23 with a new type certificate. The Baron 58P/58TC models were capable of cruising at 200 knots (370 km/h) at 8000 ft (2400 m) and 220 knots (410 km/h) at 20000 ft (6100 m), and were typically equipped with 190 US gallon (719 L) fuel tanks.

A big change in panel/system layout on 58/58TC/58P occurred in 1984, including relocating throttle, gear, flap, propeller and mixture controls to industry-standard positions.

Although the turbocharged 58TC/58P variants were discontinued in 1985, the normally aspirated Baron 58 is still in production as of 2006

The distinctive Model 35 Bonanza is one of general aviation's most famous and prolific types, and enjoyed a production life spanning four decades.

The Bonanza first flew on December 22 1945. Featuring metal construction, retractable undercarriage and high performance, it heralded a new class of high performance GA aircraft. The design also featured the distinctive Vtail, incorporated for aerodynamic efficiency and reduced weight. Deliveries of production aircraft began in 1947.

Subsequent development led to a significant family of subtypes. Briefly these are the A35 of 1949 with a greater max takeoff weight; the B35 with a 146kW (196hp) E1858 engine; the 153kW (205hp) E18511 powered C, D and E models through to 1954; the F and G35 with third cabin window and 170kW (225hp) E2258 of the mid fifties; the 180kW (240hp) Continental O470G powered H35 of 1957; the fuel injected 187kW (250hp) powered J35; 1960's M35 with larger rear windows; and the N35 and P35 with a 195kW (260hp) IO470N and greater max takeoff weight.

Then followed the redeveloped S35 of 1964 with six seats and redesigned rear cabin, optional three blade prop, 215kW (285hp) IO520B engine and yet greater weights; the heavier V35 of 1966; and turbocharged V35TC; V35A and V35ATC of 1968 with more raked windscreen; and the V35B and V35BTC (just seven built) from 1970. The V35B remained in production until 1982 and underwent a number of detail changes in that time.

The Beech 1900 19 seat commuter was chosen along with the smaller 1300, both developments of the King Air 200, and the C99 for Beech's reentry into the regional airliner market in 1979.

The most obvious change from the King Air 200 to the 1900C is the substantially lengthened fuselage (17.63m/57ft 10in compared to 13.34m/43ft 9in). Other changes include more powerful engines, a modified tail with tailets, and stabilons on the lower rear fuselage.

Development of the 1900 commenced in 1979, with first flight occurring on September 3 1982. US FAA certification was awarded in November 1983, prior to the 1900C's entry into service in February the following year. The first ExecLiner corporate transport version was delivered in mid 1985.

During the course of 1900C production a wet wing was introduced increasing fuel capacity by 927 litres (204Imp gal/245US gal), while military transport, maritime patrol and electronic surveillance versions were offered.

Beech announced the improved 1900D at the US Regional Airlines Association meeting in 1989, with the prototype, a converted 1900C, first flying on March 1 1990. Production switched to the improved model in 1991, with first deliveries (to Mesa Air) that November. The main change introduced on the 1900D was the substantially deeper fuselage with standup headroom. In addition it also introduced larger passenger and freight doors and windows, twin ventral strakes and auxiliary horizontal fixed tails, while more powerful engines and winglets improve hot and high performance.

The 1900D has sold particularly well. For example the 1900D's biggest customer is Mesa Airlines, a United Airlines feeder, which has placed total firm orders for 118. A 1900D delivered to Impulse Airlines in Australia in March 1997 was the 500th 1900 built.

The Beech 1900 19 seat commuter was chosen along with the smaller 1300, both developments of the King Air 200, and the C99 for Beech's reentry into the regional airliner market in 1979.

The most obvious change from the King Air 200 to the 1900C is the substantially lengthened fuselage (17.63m/57ft 10in compared to 13.34m/43ft 9in). Other changes include more powerful engines, a modified tail with tailets, and stabilons on the lower rear fuselage.

Development of the 1900 commenced in 1979, with first flight occurring on September 3 1982. US FAA certification was awarded in November 1983, prior to the 1900C's entry into service in February the following year. The first ExecLiner corporate transport version was delivered in mid 1985.

During the course of 1900C production a wet wing was introduced increasing fuel capacity by 927 litres (204Imp gal/245US gal), while military transport, maritime patrol and electronic surveillance versions were offered.

Beech announced the improved 1900D at the US Regional Airlines Association meeting in 1989, with the prototype, a converted 1900C, first flying on March 1 1990. Production switched to the improved model in 1991, with first deliveries (to Mesa Air) that November. The main change introduced on the 1900D was the substantially deeper fuselage with standup headroom. In addition it also introduced larger passenger and freight doors and windows, twin ventral strakes and auxiliary horizontal fixed tails, while more powerful engines and winglets improve hot and high performance.

The 1900D has sold particularly well. For example the 1900D's biggest customer is Mesa Airlines, a United Airlines feeder, which has placed total firm orders for 118. A 1900D delivered to Impulse Airlines in Australia in March 1997 was the 500th 1900 built.

The 412 family is a development of the 212, the major change being an advanced smaller diameter four blade main rotor in place of the 212's two blade unit.

Development of the 412 began in the late 1970s and two 212s were converted to the new standard to act as development aircraft for the program. The first of these flew in August 1979, and the 412 was awarded VFR certification in January 1981. That same month the first delivery occurred. Subsequent development led to the 412SP, or Special Performance, with increased fuel capacity, higher takeoff weight and more optional seating arrangements. The 412HP, or High Performance, superseded the 412SP in production in 1991. Features include improved transmission for better hovering performance.

The current standard production model is the 412EP, or Enhanced Performance. The 412EP features a PT6T3D engine and a dual digital automatic flight control system fitted as standard, with optional EFIS displays. Fixed tricycle landing gear is optional.

Meanwhile in Indonesia, IPTN has a licence to build the 412SP, which it calls the NBell412. IPTN has a licence to build up to 100 NBell412s.

Like the 212, the 412 is in widespread use for a number of utility roles, including EMS and oil rig support, its twin engine configuration being an asset, particularly in the latter role. It too is in military service, Canada once again being a major customer (including 100 recently delivered 412EP based CH-146 Griffons).

The 747-400 is the latest, longest ranging and best selling model of the 747 family.

Boeing launched the 747-400 in October 1985 and the first development aircraft first flew on April 29 1988. US certification (with PW-4000s) was awarded in January 1989.

The 747-400 externally resembles the -300, but it is a significantly improved aircraft. Changes include a new, two crew digital flightdeck with six large CRT displays, an increased span wing with winglets (the -400 was the first airliner to introduce winglets), new engines, recontoured wing/fuselage fairing, a new interior, lower basic but increased max takeoff weights, and greater range.

Apart from the basic passenger 747-400 model, a number of variants have been offered including the winglet-less 747-400 Domestic optimised for Japanese short haul domestic sectors, the 747-400M Combi passenger/freight model, and the 747-400F Freighter (which combines the 747-200F's fuselage with the -400's wing).

The latest model is the 747-400ER, which was launched on November 28, 2000 when Qantas placed an order for 6. The -400ER has the same size as the -400, but has more range or payload capability. The MTOW was increased by 15,870kg (35,000lb) to 412,770kg (910,000lb), giving a further range of 805km (435nm) or a 6800kg (15,000lb) greater payload. The -400ER also features a wholly new cabin interior with larger luggage bins, and several flight deck improvements.

The -400ER incorporates the strengthened wing, body, and landing gear of the -400F, plus an auxiliary fuel tank in the forward cargo hold, and an optional second one. Operators who don't need these can remove them both, gaining additional cargo volume.

The first 747-400ER was rolled out in June 2002, and flew for the first time on July 31, 2002, and this was the 1308th 747 to fly.

A cargo version, the 747-400ERF, followed the standard -400ER, and was launched April 30, 2001 on an order by leasing company ILFC for 5. The first -400ERF is the 1315th 747 built. The -ERF has the same MTOW as the -ER, and this will give an extra range of 970km (525nm), or an extra payload of 9980kg (22,000lb) at MTOW compared with the standard -400F.

Shortly before delivery of the first -400ER, Boeing had received orders for 15 ER/ERFs from 5 customers.

The 747-400 is the latest, longest ranging and best selling model of the 747 family.

Boeing launched the 747-400 in October 1985 and the first development aircraft first flew on April 29 1988. US certification (with PW-4000s) was awarded in January 1989.

The 747-400 externally resembles the -300, but it is a significantly improved aircraft. Changes include a new, two crew digital flightdeck with six large CRT displays, an increased span wing with winglets (the -400 was the first airliner to introduce winglets), new engines, recontoured wing/fuselage fairing, a new interior, lower basic but increased max takeoff weights, and greater range.

Apart from the basic passenger 747-400 model, a number of variants have been offered including the winglet-less 747-400 Domestic optimised for Japanese short haul domestic sectors, the 747-400M Combi passenger/freight model, and the 747-400F Freighter (which combines the 747-200F's fuselage with the -400's wing).

The latest model is the 747-400ER, which was launched on November 28, 2000 when Qantas placed an order for 6. The -400ER has the same size as the -400, but has more range or payload capability. The MTOW was increased by 15,870kg (35,000lb) to 412,770kg (910,000lb), giving a further range of 805km (435nm) or a 6800kg (15,000lb) greater payload. The -400ER also features a wholly new cabin interior with larger luggage bins, and several flight deck improvements.

The -400ER incorporates the strengthened wing, body, and landing gear of the -400F, plus an auxiliary fuel tank in the forward cargo hold, and an optional second one. Operators who don't need these can remove them both, gaining additional cargo volume.

The first 747-400ER was rolled out in June 2002, and flew for the first time on July 31, 2002, and this was the 1308th 747 to fly.

A cargo version, the 747-400ERF, followed the standard -400ER, and was launched April 30, 2001 on an order by leasing company ILFC for 5. The first -400ERF is the 1315th 747 built. The -ERF has the same MTOW as the -ER, and this will give an extra range of 970km (525nm), or an extra payload of 9980kg (22,000lb) at MTOW compared with the standard -400F.

Shortly before delivery of the first -400ER, Boeing had received orders for 15 ER/ERFs from 5 customers.

The Bell BA 609 is set to become the first civil application of the revolutionary tiltrotor technology, taking advantage of its experience with the military V22 Osprey.

Bell pioneered the tiltrotor concept with the experimental XV3 which first flew as early as 1957 and then with NASA developed the XV15 experimental demonstrator which first flew in 1977. In conjunction with Boeing it is building the military V-22 Osprey - the first production Ospreys are due to be delivered to the US Marines in 1999.

In late 1996 Bell and Boeing announced that they intended to use their expertise and experience with the V22 to develop a nine seat civil tiltrotor. The Bell Boeing 609 was formally unveiled on November 18 1996. However in early 1998 Boeing announced its withdrawal from the program as a risk sharing partner to remain as a major subcontractor. Then in September that year Bell announced that Agusta would become a risk sharing development partner in the redesignated BA 609. Agusta will participate in BA 609 development, manufacture components and assemble BA 609s for European and other markets.

First flight for the BA 609 is planned for mid 1999 with certification and first deliveries scheduled for April 2002. (The US FAA is drawing up a new certification category for tiltrotors and a new pilot type rating.)

The benefits of a tiltrotor are that it has the vertical takeoff, landing and hovering abilities of a helicopter combined with fixed wing turboprop speed and performance. As such Bell anticipates that the 609 will compete against helicopters such as the Sikorsky S76 and turboprops such as Beech's King Air. As well as point to point corporate transport Bell envisages that the 609 will be used for offshore oil rig support, search and rescue and medevac missions, where its unique capabilities would be particularly useful.

The 609 will incorporate advanced technologies such as a glass cockpit, flybywire flight controls and a composite construction fuselage. Power will be from two PT6C67A turboprops.

The 609 could form the basis for a family of civil tiltrotors.

Boeing announced that it was developing a stretched development of the 767-200 in February 1982.

The resulting 767-300 features a 6.42m (21ft 1in) stretch consisting of fuselage plugs forward (3.07m/10ft 1in) and behind (3.35m/11ft) the wing centre section. The flightdeck and systems were carried directly over from the 767-200, the only other changes were minor, and related to the increased weights of the new version. Initially the max takeoff weight was the same as the later 767-200ER.

The 767-300 flew for the first time on January 30 1986, and was awarded certification and entered service in September that year. The higher weight Extended Range ER version flew on December 19 1986, while RollsRoyce RB-211-524G engines became available from 1989. The range of the 767-300ER has proven to be very popular with a number of airlines using them for long range low density flights.

In 1993 Boeing launched the 767-300F General Market Freighter. Changes include strengthened undercarriage and wing structure, a cargo handling system, no cabin windows and a main deck freight door. Capacity is 24 containers.

The BN-2 Islander was Britten-Norman's second original design, work on which began during 1963.

Developed as a Dragon Rapide replacement, the emphasis was on producing a rugged and durable aircraft that had good field performance, low operating costs and was easy to maintain. One unusual feature is that there is no centre aisle between seats in the main cabin, instead there are three doors along each side of the fuselage for passenger boarding. The prototype BN-2 Islander was powered by two 155kW (210hp) IO-360s and first flight was on June 13 1965.

The first production machines were powered by 195kW (260hp) IO-540s and were simply designated BN-2, the first flew in 1967. A small number were built before production switched to the BN-2A which introduced fairings to the main undercarriage legs, wing leading edge and flap droop, and an increased max takeoff weight. From 1970 the base A model was the BN-2A-6 and the BN-2A-7 had extended wingtips, while the BN-2A-2 and BN-2A-3 were powered by the 225kW (300hp) IO-540, the latter with the extended wingtips.

Appearing in 1972 were the 195kW (260hp) powered BN-2A-26 and extended wingtips BN-2A-27, and the 225kW (300hp) BN-2A-20 and extended wingtips BN-2A-21, all four models having higher weights. Further improvements came with the BN-2B range with higher weights, improved interior and instrument panel and shorter diameter props. The 26, 27, 20 and 21 variants were available as before. The 27 and 21 were later dropped while the BN-2B-20 and BN-2B-26 remain in production. The turboprop (Allison 250) powered BN-2T has been built since 1981.

In September1979 Britten-Norman became Pilatus Britten-Norman, in July 1998 it was renamed back to Britten-Norman, and from April 2000 it became B-N Group.

The introduction of the Cessna 150 marked Cessna's return to the two seat trainer market after a six year absence and resulted in the most prolific and successful two seat trainer line in history.

Development of the original 150 began in the mid 1950s, resulting in a first flight in September 1957. This modern, all new aircraft followed the Cessna conventions then gaining favour of a strut braced high wing, all metal construction and tricycle undercarriage. Production began in September 1958.

What followed was a continuous process of product improvement, although throughout the 150 model life the Continental O-200A powerplant remained unchanged. One of the most significant model changes was the 150D of 1964 which introduced the wraparound rear window. Most versions were built in Standard, Commuter and Trainer forms with differing equipment levels, while licence production was undertaken in France by Reims and in Argentina by DINFIA. Aerobat versions were stressed for limited aerobatic work.

The 152 was a response to availability problems with 80/87 octane fuel, and used the 150's fuselage coupled with a Lycoming O-235 running on 100 Octane. The 152 replaced the 150 from 1977 and remained in production until late 1985. It too was progressively updated, offered in A152 Aerobat form, and also built in France

The 180 started life as a more powerful development of the 170, and evolved into a family of useful utility aircraft that was in production for over three decades.

The first 180s were essentially Model 170s with a more powerful 170kW (225hp) O-470-A engine. The first of the type flew in 1952 and deliveries began in February the following year. The 180's career as a high performance single was short lived due to the arrival of the tricycle 180 based 182 in 1956, but by then the type had established itself a useful niche as a utility aircraft.

Progressive updating of the line led to a range of updated models including the 170kW (230hp) 180A, and 1964's 180G with a third cabin window which from 1966 was offered as a six seater, by then having the same fuselage as the more powerful 185 Skywagon. The Skywagon name was applied to the 180 in 1969. The 180 remained in production until 1981.

The first 185 Skywagon flew in July 1960. It differed from the 180 in having a more powerful engine (195kW/260hp) and larger cabin, allowing six seats. Updated models include the 225kW (300hp) A185E from 1967 and the AgCarryall capable of chemical spraying.

During its production life the Cessna 210 was at the top of the Cessna single piston engine model lineup, positioned between the 182 and the 310 twin.

First flight of the 210 occurred in January 1957. This new aircraft featured for the first time on a Cessna aircraft retractable undercarriage and swept back vertical tail surfaces. The 210 entered production in late 1959, and from that time the line was constantly updated.

Notable early upgrades include the 210B which introduced the wraparound rear windows, the 210D with a more powerful (210kW/285hp) engine and introduced the Centurion name, and the turbocharged T210F. The 210G introduced a new strutless cantilever wing, increased fuel capacity, restyled rear windows and enlarged tail surfaces. Continual development of the 210 and T210 range continued through until production ceased in 1985.

A significant development of the T210 was the high performance, pressurised P210 which first appeared in 1978. The pressurisation system meant that the cabin's internal altitude was equivalent to 8000ft when flying at 17,350ft.

In 1998 Cessna was considering returning the 210 to production.

The popular 205/206/207 line began life as a four seat utility aircraft, stretched from the 182 Skylane.

In its initial form the 205 (originally 210-5) was essentially a fixed undercarriage derivative of the 210 Centurion, optimised for utility roles, giving more baggage space. Introduced to the Cessna lineup in 1962, the 205 was powered by the same IO-470 engine as the 210B and featured an additional small cargo door on the left side of the fuselage. It later gained it's 6th seat.

The 205 lasted in production until 1964 when it was replaced by the more powerful 206, which came in 2 options, the P206 Super Skylane and the U206 Super Skywagon, which respectively meant Passenger and Utility, the U206 featuring larger double cargo doors on the right fuselage side. Continuous improvement followed, including introduction of turbocharged and fuel injected models. The 'Super' prefix for the Super Skywagon was dropped in 1969 and the Stationair name was adopted in 1971. Production originally ceased in 1985.

The 207 Skywagon meanwhile featured a 1.07m (3ft 6in) fuselage stretch (allowing seating for seven) and became available from 1969. Known as the Stationair 7 from 1978, it was replaced by the 207A Stationair 8 from 1979 which had seating for an eighth occupant. Production ended in 1984. A few were built in France by Reims as the F207. Several 206 and 207 aircraft have been converted to turbine power by Soloy as the Turbine 206 and 207.

The 206 is the third Cessna single to be returned to production at the company's new Independence plant in Kansas. Two versions are offered, the normally aspirated 206H and turbo T206H. The T206H first flew on August 6 1996, powered by a TIO-580, while the normally aspirated 206H, powered by an IO-580, followed on November 6. A decision to switch to the TIO-540 and IO-540 because of reliability concerns pushed back production by about 10 months. The 206H was certificated on September 9 1998, the T206H on October 1.

TDM PJ-CAA 'Isla Saona'

TL PJ-CAC 'El Portillo'

TDS PJ-CAB 'Las Terrenas'

TA N2062T 'Angoon'

TA N2066T 'Chevak'

With sales exceeding the 1000 mark the useful Caravan is a popular utility workhorse worldwide.

Design work for the Caravan dates back to the early eighties. First flight of a prototype occurred on December 9 1982 and certification was granted in October 1984. When production began the following year it became the first all new single engine turboprop powered aircraft to achieve production status.

The Caravan I has had a close association with US package freight specialist Federal Express (FedEx), on whose request Cessna especially developed two pure freight versions. The first of these was the 208A Cargomaster (40 delivered), the second was the stretched 208B Super Cargomaster (260 delivered). The first Super Cargomaster flew in 1986 and features a 1.22m (4ft) stretch and greater payload capacity, including an under fuselage cargo pannier. FedEx's aircraft lack cabin windows.

The 208B Grand Caravan first flew in 1990 and like the Super Cargomaster is a stretched version of the basic Caravan powered by a 505kW (675shp) PT6A-114. It can seat up to 14 passengers.

Announced at the 1997 NBAA convention, the 208-675 has replaced the basic 208. It combines the standard length airframe of the 208 with the more powerful PT6A-114 of the 208B.

Underbelly cargo pods, floats and skis are offered as options on the Caravan I family, and the type is easily converted from freight to passenger configurations.

A military/special missions version of the 208A, dubbed the U-27A, is also on offer. The Brazilian Air Force designation is C-98.

Soloy is offering a dual-engine conversion of the 208B, named Pathfinder 21. This version is powered by a 991kW (1329shp) Pratt & Whitney Canada/Soloy Dual Pac powerplant, consisting of two PT6D-114A engines driving a single propeller. Other distinguishing features of the Pathfinder 21 include a 72in cabin stretch behind the wing and a large integral cargo pod.

With sales exceeding the 1000 mark the useful Caravan is a popular utility workhorse worldwide.

Design work for the Caravan dates back to the early eighties. First flight of a prototype occurred on December 9 1982 and certification was granted in October 1984. When production began the following year it became the first all new single engine turboprop powered aircraft to achieve production status.

The Caravan I has had a close association with US package freight specialist Federal Express (FedEx), on whose request Cessna especially developed two pure freight versions. The first of these was the 208A Cargomaster (40 delivered), the second was the stretched 208B Super Cargomaster (260 delivered). The first Super Cargomaster flew in 1986 and features a 1.22m (4ft) stretch and greater payload capacity, including an under fuselage cargo pannier. FedEx's aircraft lack cabin windows.

The 208B Grand Caravan first flew in 1990 and like the Super Cargomaster is a stretched version of the basic Caravan powered by a 505kW (675shp) PT6A-114. It can seat up to 14 passengers.

Announced at the 1997 NBAA convention, the 208-675 has replaced the basic 208. It combines the standard length airframe of the 208 with the more powerful PT6A-114 of the 208B.

Underbelly cargo pods, floats and skis are offered as options on the Caravan I family, and the type is easily converted from freight to passenger configurations.

A military/special missions version of the 208A, dubbed the U-27A, is also on offer. The Brazilian Air Force designation is C-98.

Soloy is offering a dual-engine conversion of the 208B, named Pathfinder 21. This version is powered by a 991kW (1329shp) Pratt & Whitney Canada/Soloy Dual Pac powerplant, consisting of two PT6D-114A engines driving a single propeller. Other distinguishing features of the Pathfinder 21 include a 72in cabin stretch behind the wing and a large integral cargo pod.

The sleek Cessna 310 was the first twin engine design from Cessna to enter production after WW2.

The 310 first flew on January 3 1953. The modern rakish lines of the new twin were backed up by innovative features such as engine exhaust thrust augmentor tubes and the storage of all fuel in tip tanks. Deliveries commenced in late 1954.

The first significant upgrade to the 310 line came with the 310C of 1959, which introduced more powerful 195kW (260hp) IO-470-D engines. The 310D of 1960 featured swept back vertical tail surfaces. An extra cabin window was added with the 310F. A development of the 310F was the turbocharged 320 Skyknight, with TSIO-470-B engines and a fourth cabin side-window. The Skyknight was in production between 1961 and 1969 (the 320D, E and F were named Executive Skyknight), when it was replaced by the similar Turbo 310.

The 310G introduced the 'stabila-tip' tip tanks, while the 310K replaced the rear two windows on each side with a single unit. Subsequent significant developments include the 310Q and turbocharged T310Q with redesigned rear cabin with a skylight window, and the final 310R and T310R, identifiable for their lengthened noses. Production ended in 1980.

USAF military versions were the L-27A (310A) and L-27B (310M) Blue Canoe, later redesignated U-3A and U-3B.

When released, the Cessna 340 joined the Beechcraft Duke as the only other six seat pressurised piston twin from a major manufacturer, positioned in Cessna's product line between the 310 and the eight seat 414 and 421.

Development of the 340 began in 1969, but the loss of the prototype early in 1970 set back the development program so that production deliveries did not begin until early 1971. The resulting aircraft borrowed heavily from other Cessna twins of the time including the wings from the 414 and the 310's undercarriage and a similar tail unit. Design features of the new aircraft included a pressurisation system with a differential of 0.29bars (4.2psi) that kept the cabin's internal altitude at 8000ft while the aircraft was at 20,000ft, an all new fail safe fuselage and an integral airstair door.

Initial production 340s were powered by two 210kW (285hp) turbocharged Continental TSIO-520-K engines, but these were replaced on the improved 340A, which was first introduced in 1976. Power for the 340A was supplied by two 230kW (310hp) TSIO-520-NBs, while other improvements included reduced diameter props and a slight increase in weights. The 340A was offered in optional 340A II and 340A III forms with various levels of IFR avionics fitted.

The Cessna 335 is an unpressurised, lighter weight and thus lower cost development of the 340. Available from 1979, aside from being unpressurised it differed in having 225kW (300hp) TSIO-520-EB engines. Although claimed by Cessna as the lowest priced cabin class business twin on the market, just 64 335s were built before production was terminated in 1980.

Production of the 340 continued until 1984.

Through their pushpull engine configuration the twin boom Cessna 336 and 337 were designed to overcome conventional twins' problems of poor engine out asymmetric flight handling characteristics.

Cessna called the layout concept Centre Line Thrust, as the nose mounted tractor and rear fuselage mounted pusher engine eliminated asymmetric handling problems normally experienced when one of a twin's engines fails. The concept was recognised by the US FAA which created a new centre thrust rating for pilots to be rated on the type.

The Model 336 Skymaster first flew on February 18 1961, but significant improvements to the design were made before production aircraft were delivered. Changes included more powerful engines, a larger fuselage with seating for six, and revised wing, tail and rear engine cowling. The 336 was delivered from mid 1963 and production lasted until late 1964 when it was replaced by the 337 Super Skymaster ('Super' was later dropped) which was released in February 1965.

The improved 337 introduced retractable undercarriage, more powerful 160kW (210hp) engines, a dorsal air intake for the rear engine, variable cowl flaps, repositioned forward engine and cowl for improved visibility, and higher weights.

Subsequent development resulted in the turbocharged T337 (first released in the 1967 model year, dropped in 1972 and relaunched in 1978), while the ultimate 337 was the T337G Pressurized Skymaster, introduced from August 1972.

Development of the 337 continued in France by Reims after Cessna production ended in 1980, resulting in the FTB337 Milirole, a military STOL version with underwing hardpoints. Cessna also built more than 500 337s as O-2s for the US Air Force, used largely in the Forward Air Control role.

The Citation X is Cessna's largest, fastest and longest range aircraft yet, and Cessna claims it to be the fastest civil transport in service other than the supersonic Concorde.

The Citation X (as in the Roman numeral, not the letter, and Cessna's Model 750) is also the largest member of business aviation's biggest corporate jet family, the Citation series.

The design objectives behind the Citation X included transcontinental USA and trans Atlantic range in a mid size package that cruises faster than any other business jet available. This high speed cruise capability, which Cessna says is 105 to 210km/h (55 to 113kt) faster than other mid size corporate jet, means the X can save up to one hour's flight time on transcontinental US flights, flying from Los Angeles to New York with normal wind conditions in 4 hours 10 minutes. Because of its ability to cruise at high speed at high altitudes, Cessna also says the Citation X will consume less fuel than current jets on such a transcontinental flight.

The X's FADEC equipped Allison AE 3007A turbofans are very powerful for an aircraft of the X's size, while the highly swept (37°) wings are also long in span.

Other design features of the Citation X include the fuselage cross section of the Citation III, VI and VII but with more efficient use of internal space that allows greater head and shoulder room, an area ruled, waisted rear fuselage, trailing link main undercarriage units and a modern Honeywell Primus 2000 EFIS avionics suite with five colour CRT displays.

Cessna announced that it was developing the Citation X in October 1990 at that year's NBAA conference. The prototype was publicly rolled out in September 1993 and flew for the first time on December 21 that year. Certification was granted on June 3 1996, with the first customer delivery (to golfer Arnold Palmer) that month.

A Citation X was the 2500th Citation to be delivered, handed over on September 10 1997. The USA's National Aeronautics Association awarded its prestigious Collier Trophy to the Citation X design team in February 1997.

De Havilland Canada's first purpose designed bush aircraft, the Beaver was that company's most successful program sales wise (both military or civil), with almost 1700 built in a production run lasting two decades.

Beaver development work began in 1946 and the Ontario Department of Lands and Forests had considerable input into the final design and configuration of this rugged and versatile utility. A prototype flew on August 16 1947, with seating for five or six, although the production Beaver grew slightly to seat an extra two passengers by the time civil certification was awarded in March 1948.

The only major development of the Beaver (aside from a one off powered by a 410kW/550hp Alvis Leonides 502/4 radial engine) was the Turbo Beaver. First flown in December 1963 it featured a Pratt & Whitney PT6A6 turboprop, which offered lower empty and higher takeoff weights, and even better STOL performance. The Turbo Beaver's cabin was also longer, allowing maximum accommodation for 11, including the pilot. Externally, the Turbo Beaver had a much longer and reprofiled nose, and squared off vertical tail. DHC also offered conversion kits enabling piston powered Beavers to be upgraded to Turbo standard. Other conversions have been performed.

Lockheed's L-100 freighters are the civil equivalents of the venerable military C-130 Hercules, and have proven to be of great utility, particularly in undeveloped countries.

Lockheed initiated design of the Hercules in response to a 1951 US Air Force requirement for a turboprop powered freighter. This resulted in the C-130 Hercules, which first flew in prototype form on August 23 1954. Design features included the high mounted wing, four Allison 501/T56 turboprops and the rear loading freight ramp. The USAF ordered the C-130 into series production in September 1952, and since that time more than 2500 have been built.

The C-130's appeal to freight operators led Lockheed to develop a civil version. The first commercial versions were based on the C-130E model, and a demilitarised demonstrator first flew in April 1964. This initial civil development, the L-100 (L-382), was awarded civil certification in February 1965. This model was soon followed up by the series L-100 (L-382B), which introduced an improved freight handling system.

Sales of these initial versions were slow, leading Lockheed to develop the 2.54m (8ft 4in) stretched L-100-20 (L-382E), which offered better freight capacity and operating economics. The L-100-20 was certificated in October 1968, but was soon followed by the even longer L-100-30 (L-382G). The -30 was 2.03m (6ft 8in) longer than the -20, first flew in August 1970, and was delivered from December that year. Most civil Hercules sales have been of the L-100-30 variant. Although basically a civil aircraft, several L-100s are in service with military operators, e.g. in Algeria, Gabon and Kuwait. The last L-100 was built in 1992, while the last military Allison 501/T56 powered C-130 was delivered in 1996.

The L-100J would be a commercial derivative of the new generation C-130J Hercules II. Improvements would include new 3425kW (4591shp) Rolls-Royce (Allison) AE-2100D3 advanced turboprop engines driving six blade props, two crew EFIS flightdeck and significantly lower maintenance and operating costs. The C-130J first flew on April 5 1996, while US FAA civil certification was awarded in September 1998. The L-100J would be based on the stretched fuselage C-130J-30, but in 2000 the program was frozen as Lockheed martin focussed on the military variants.

The PA-32 series began life as the Cherokee Six, a significantly modified six seat development of the PA-28 Cherokee series.

While similar in configuration to the Cherokee, the Cherokee Six differed in a number of major areas. Two of the big differences were implied in its name, a six cylinder O-540 or IO-540 powerplant, and the six seat configuration. While the wing was based on the Cherokee's, the fuselage was substantially larger, with strengthened undercarriage and a larger tail.

The Cherokee Six first flew on December 6 1963, while deliveries of production PA-32-260s began from mid 1965. Development led to a range of improved models, starting with the 225kW (300hp) fuel injected IO-540 powered Cherokee Six 300 (PA-32-300). Production of the 260 and 300 ended in the late 1970s, but in the meantime they had been joined by the PA-32R Cherokee Lance. The Cherokee Lance, or just Lance from mid 1977 with the introduction of the improved Lance II, was a retractable undercarriage development. The Lance II and turbocharged PA-32R-300T Turbo Lance also introduced a T-tail as the PA-32RT and remained in production to late 1979.

The Lance II and Cherokee Six were replaced by the Saratoga. Available in fixed or retractable undercarriage form, with standard or turbocharged powerplants, the major change was the new increased span tapered wing.

Production of the Saratoga ceased in 1985, but New Piper reintroduced the Saratoga II HP in 1993 with aerodynamic improvements and a revised instrument panel and interior. The turbocharged Saratoga II TC was introduced in 1997. 1999 models introduce new Garmin and S-TEC avionics. A five seat interior with a entertainment/workstation console (similar to that in the Seneca V) is optional.

The PA-32 was also built under licence in Brazil as the Embraer EMB-720 Minuano, and the PA-32R as the EMB-721 Sertanejo, while Chincul in Argentina built the PA-32 as PA-A-32, the PA-32R as PA-A-32R, and the PA-32RT as the PA-A-32RT.

Production of the Saratoga ceased in 1985, but Piper reintroduced the Saratoga II HP in 1993 with aerodynamic improvements and a revised instrument panel and interior. The turbocharged Saratoga II TC was introduced in 1997. The 1999 models introduced new Garmin and S-TEC avionics. A five seat interior with an entertainment/workstation console (similar to that in the Seneca V) is optional.

The most successful six place light twin since its introduction, the Seneca is a twin engine development of the Cherokee Six.

Seneca development began when Piper flew a converted trimotor Cherokee Six, designated PA-32-3M, fitted with two additional 85kW (115hp) Lycomings O-235 on either wing. The subsequent twin engine prototype PA-34-180 Twin 6 first flew with two 135kW (180hp) Lycomings, while the definitive standard third Seneca prototype, the PA-34-200 Twin 6, first flew in October 1969 with fuel injected 150kW (200hp) IO-360s. Production deliveries of the initial PA-34-200 Seneca began in late 1971.

Handling and performance criticisms were addressed from the 1974 model year with the PA-34-200T Seneca II which introduced changes to the flight controls and, more importantly, two turbocharged Continental TSIO-360-Es. Piper originally planned that the follow-on PA-34-220T Seneca III would feature a T-tail, but these plans were dropped and the main changes introduced were counter rotating 165kW (220hp) TSIO-360s and a revised interior and instrument panel. Introduced in 1981, the Seneca III was replaced by New Piper's improved PA-34-220T Seneca IV in 1994 with aerodynamic refinements, axisymetric engine inlets and a revised interior.

The current PA-34-220T Seneca V was introduced in January 1997. It features intercooled turbocharged L/TSIO-360-RB engines which maintain rated power to 19,500ft, and seating for five, with a standard entertainment/executive workstation with extendable worktable and optional phone/fax. A sixth seat in place of the workstation is optional.

The Seneca was also built or assembled by other manufacturers, AICSA in Colombia, Chincul in Argentina (as the PA-A-34), Embraer in Brazil (as the EMB-810), and PZL-Mielec in Poland (as the M-20 Mewa, partly with PZL/Franklin engines).

Conversions are made by Seguin as the Princess, and by Robertson as the Super Seneca I and II.

The Kodiak is a high-wing turboprop-powered fixed-tricycle-gear all-metal aircraft suitable for humanitarian applications in unimproved areas; a skydiving version has been certified. Its cabin is not pressurized. The Kodiak bears a strong resemblance to the Cessna Caravan, but it is substantially smaller and lighter than the Cessna, intended more for the utilitarian market (although an executive interior, the "Summit package" with club seating, is planned for introduction in summer 2009).

Large contributors to the Kodiak's STOL performance are a fixed, discontinuous leading edge on the outboard wing and the popular, high performance Pratt & Whitney PT6A-34 turboprop engine (750 hp @ TO). The PT6 has a reputation for reliability. Variants of the engine have been in service since the 1960s.

Passenger seats in the Kodiak are track-mounted, making them easily removable when cargo is to be carried. It has standard access doors for pilot and co-pilot positions, with a large clamshell door in the aft fuselage for cargo loading or for access to the other 6 passenger positions (the lower half of the clamshell door has automatically extending/retracting steps).

• Typical price = $1,800,000
• Seats = 8 (1 Pilot, 7 Passengers)
• Engine = P & W PT6, 750 shp takeoff, 700 shp continuous @ 2200 rev/minute
• Propeller = Hartzell 96 inch diameter, four-blade, full-feathering, reversible
• Prop clearance = 19 inch
• Length = 33.4 feet
• Height = 15.4 feet
• Wingspan = 45.0 feet
• Wing area = 240 feet²
• Takeoff weight = 6,750 pounds
• Landing weight = 6,690 pounds
• Useful load = 3,100 pounds
• Useful load w/full fuel = 911 pounds
• Approx empty weight= 3,700 pounds
• Usable fuel = 320 US gallons/2,144 pounds
• S/L rate of climb = 1,540 feet/minute maximum
• Certified ceiling = 25,000 feet
• Takeoff ground roll= 760 feet
• T/O w 50' obstacle = 1,212 feet
• Landing ground roll= 915 feet without thrust reverse usage
• Landing w 50' obstacle = 1,681 feet
• Cruise speed = 185 knots maximum
• Range = 1,032 nautical mile @ 12,000 feet, 179 knots
• Endurance = 5.9 hours @ 10,000 feet, high-speed cruise
• Stall speed no-flaps = 77 knots
• Stall speed, flaps = 59 knots
• Maneuvering speed = 142 knots @ maximum weight

The MD-11 is a modernised, slightly stretched and re-engined development of the DC-10 trijet.

Launched on December 30 1986 (following a launch order from British Caledonian for three placed earlier that month), the MD-11 was the result of a two year study to find a replacement for the DC-10. First flight occurred on January 10 1990, certification was granted in November that year, and the first one was delivered on December 7 1990 to Finnair.

Compared to the DC-10, the MD-11 features a 5.71m (18ft 9in) fuselage stretch, winglets, modified tail with less sweepback, an advanced two crew six screen EFIS flightdeck, restyled main cabin interior and new engine options. Variants offered were the longer range MD-11ER available from early 1996, MD-11F freighter, MD-11C Combi and MD-11CF convertible passenger/freighter models.

McDonnell Douglas at various times proposed MD-11 developments aimed at increasing seating through stretches and underfloor panorama deck seating. In 1996 MDC looked closely at the MD-XX, MD-11 variants with a new wing. Two versions were proposed, one with the standard MD-11 fuselage and a 15,565km (8400nm) range, the other a stretched 375 seater. These were not launched.

In November 1997 following the Boeing/McDonnell Douglas merger Boeing announced that the MD-11 would be retained in production, primarily as a freighter. However in June 1998 Boeing reversed that decision, saying that due to a lack of market demand production would be wound up. The last MD-11 built, a MD-11F for Lufthansa cargo, was delivered February 22 2001.

The PC-12 is a King Air class and size turboprop aimed at corporate transport and regional airliner operators. It is the latest in a line of single engined PT6 powered Pilatus products.

Pilatus announced it was developing the PC-12 at the National Business Aircraft Association's annual convention in October 1989. First flight of the first of two prototypes occurred on May 31 1991. Certification was originally planned for mid 1993 but a redesign of the wings with the addition of winglets to ensure performance guarantees were met pushed this back, with Swiss certification awarded on March 30 1994 and US FAA FAR Part 23 approval following on July 15 1994.

Compared to the King Air 200 twin, its major competitor, the PC-12's most significant design feature is its use of a single PT6A-67B turboshaft. Internally the PC-12's cabin is also longer (by 6cm/2.4in) and wider (by 15cm/6in) than the King Air 200's, and the same height. The cockpit features EFIS displays and the PC-12 is certificated for single pilot operation while each PC-12 built features a standard cargo door in the rear fuselage. Weather radar is an option but has been fitted to all production aircraft thus far. From 1997 the increased 4.5 tonne MTOW has been standard. New, smaller winglets were introduced in 1998.

The PC-12 is offered in standard nine seat airliner form, in a four passenger seat/freight combi version and as a six place corporate transport. A pure freighter model is under consideration. The PC-12 Eagle is a military special missions platform.

Most PC-12s built thus far have been corporate transports but recent important regulatory changes in Australia, Brazil, Canada and the USA have cleared single engine turboprops for IFR RPT operations in those nations. This has opened up new potential markets for the PC12 as a regional airliner, replacing older King Airs and elderly piston twins such as the Navajo Chieftain and Cessna 400 series.

The Saab 340 proved to be a highly popular regional airliner that helped to pioneer the 30 seat turboprop class but slow sales in the late 1990s has forced Saab to cease production.

In 1979 SaabScania of Sweden and Fairchild in the USA reached an agreement to conduct joint feasibility and development studies on a 30 to 40 seat commuter airliner. The resulting SF340 design was launched in September 1980 with the aim of capturing 25 to 30% of its market. Within the 65/35 SaabFairchild partnership split Saab was responsible for the fuselage, fin and final assembly, while Fairchild was responsible for the wings, engine nacelles and empennage. The two companies selected the General Electric CT7 (a commercial development of the T700 which powers Sikorsky's S70 series of military helicopters) to power the new airliner.

The first of three SF340 prototypes first flew on January 25 1983, while the first production aircraft flew in early March 1984. US and European certification was awarded that June. From November 1 1985 Saab assumed overall responsibility for the SF340 following Fairchild's decision to divest itself of its aircraft divisions. Saab initially retained the SF340 designation but later changed it to 340A.

The first improved development of the Saab 340 was the 340B. More powerful engines improved hot and high performance, while other changes included a greater span tailplane, a higher max takeoff weight and better range. Deliveries began in September 1989.

The last development of the 340 was the 340B Plus, which introduced changes developed for the larger Saab 2000, including an improved cabin interior. The first 340B Plus was delivered in March 1994. Lack of sales and profitibility however forced Saab to cease 340 and 2000 production, with the lines winding up in 1998.