Convair CV-240 family

The Convair CV-240 was an American airliner produced by Convair from 1947 to 1954, initially as a possible replacement of the ubiquitous Douglas DC-3. While featuring a more modern design, the 240 series was able to make some inroads as a commercial airliner and also had a long development cycle which resulted in a number of civil and military variants. Although reduced in numbers through attrition, the "Convairliners" in various forms continue to fly into the 21st century.

Design and development
The design began life in a production requirement by American Airlines for an airliner to replace its Douglas DC-3s. Convair's original design, the unpressurised Model 110 was a twin-engined low-wing monoplane of all-metal construction, with seats for 30 passengers. It was powered by Pratt & Whitney R-2800 Double Wasp radial engines and was fitted with a tricycle landing gear, while the aircraft was fitted with a ventral airstair to aid passenger embarkation. The prototype Model 110, registration NX90653 first flew on July 8, 1946. By this time, American had changed their requirements to require pressurization and deemed the design to be too small. The first prototype was subsequently used by Convair for development work for the 240 series before being broken up in 1947.

To meet the requirements of airlines for a pressurized airliner, Convair produced a revised design, the Model 240. This had a longer but thinner fuselage than the Model 110, designed to accommodate 40 passengers in the first pressurized twin-engined airliner. The first Model 240 flew on March 16, 1947.

The Model 240 was followed into production by the Model 340, which had a stretched fuselage carrying an extra four seats and was fitted with longer span wings and more powerful engines to give improved performance. The first Model 340 made its maiden flight on October 5, 1951, with the type entering service in November that year. In 1954, in an attempt to compete with turboprop-powered airliners like the Vickers Viscount, Convair produced the Model 440 Metropolitan, with more streamlined cowlings and new engine exhausts and improved soundproofing for the cabin. As the "Super 240" evolved into the CV-340, and CV-440, the limit of piston-engine performance was reached and the next developments centered on conversion to turboprop power which resulted in a longer operational life for the type.

Operational history
The first delivery of a production Convairliner was to American on February 29, 1948. A total of 75 were delivered to American, with another 50 going to Western Airlines, Continental Airlines, Pan American Airways, KLM, Swissair, Sabena and Trans Australia Airlines.

A CV-240 was the first private aircraft used in a United States presidential campaign. In 1960, John F. Kennedy used a CV-240 named Caroline (after his daughter) during his campaign. This aircraft is now preserved in the National Air and Space Museum.

After the aborted negotiations with TWA and Eastern for "Super 240" orders, the production of the 240 series was temporarily halted. In response to a United inquiry, however, Convair redesigned the Super 240, calling it the CV-340. United ordered 55, and more US orders came from Braniff, Continental, Delta, Northeast and National. Other orders came from abroad, and the CV-340 proved popular in South America. The CV-340 earned an enviable reputation for reliability and profitability, and was developed into the CV-440 Metropolitan, the final piston-engined variant of the "Convairliners."

Kelowna Flightcraft Ltd. currently holds the type certificate for this aircraft.

Variants
Data from:General Dynamics Aircraft and their Predecessors

Civil variants



 * Convair Model 110
 * Unpressurized prototype with seats for 30 passengers. 89 ft (27.13 m) wingspan, 71 ft (21.64 m) length, powered by two 2,100 hp (1,567 kW) Pratt & Whitney R-2800-SC13G engines. One built.


 * Convair CV-240
 * Initial production version. Powered by two Pratt & Whitney R-2800 engines.


 * Convair CV-240-21 Turboliner
 * turboprop-powered conversion fitted with Allison T38 engines. It became the first turboprop airliner to fly in the United States (on December 29, 1950), but problems with the engines resulted in development being terminated and the prototype being converted back to piston power.
 * turboprop-powered conversion fitted with Allison T38 engines. It became the first turboprop airliner to fly in the United States (on December 29, 1950), but problems with the engines resulted in development being terminated and the prototype being converted back to piston power.


 * Convair CV-300
 * a conversion from a Convair CV-240 with two R-2800 CB-17 engines and nacelles as used on the CV-340. A CV-300 was involved in an accident that killed three members and the manager of the rock group Lynyrd Skynyrd.


 * Convair CV-340
 * Built for United Airlines and other operators including KLM, was basically a CV-240 lengthened to hold an additional four seats. The wing span was also extended for better performance at higher altitudes. The CV-340 replaced the DC-3 in United service. The airline flew 52 340s for 16 years without a fatality. KLM operated the type from spring 1953 until mid 1963. Many CV-340 aircraft were converted to CV-440 standard.


 * Convair CV-440 Metropolitan
 * CV-340 with improved soundproofing and an option of weather radar. Maximum weight rose to 49,700 lbs. An optional increase from 44 to 52 passengers was facilitated by the replacement of the carry-on luggage area with two more rows of seats, marked by the addition of an extra cabin window. This option was taken up by several airlines including Lufthansa and SAS.


 * Convair CV-540
 * Conversion from a Convair CV-340 aircraft with two Napier Eland turboprop engines in place of the piston engines. Six aircraft were converted by Napier for Allegheny Airlines.


 * Convair CV-580
 * conversion from Convair CV-340 or CV-440 aircraft with two Allison 501 D13D/H turboprop engines with four-bladed propellers in place of the piston engines with three-bladed propellers, an enlarged vertical fin and modified horizontal stabilisers. The conversions were performed by Pacific Airmotive on behalf of the Allison Engine Company.


 * Convair CV-600
 * Conversion from a Convair 240 aircraft with Rolls-Royce Dart turboprop engines with four-bladed propellers in place of the piston engines with three-bladed propellers. CV-600 conversions were performed by Convair. The CV-600 first flew with Central Airlines on 30 November 1965. The CV-600 aircraft that flew with Air Metro Airways was configured as a 40-passenger airliner. In August 2006, a single Convair CV-600 aircraft remains in airline service, with Rhoades Aviation.


 * Convair CV-640
 * Conversion from a Convair CV-340 or -440 with Rolls-Royce Dart turboprop engines with four-bladed propellers in place of the piston engines with three-bladed propellers. The conversions were performed by Convair. In August 2006, a total of nine Convair CV-640 aircraft remain in airline service, with Rhoades Aviation (three) and C&M Airways (six).


 * Convair CV5800
 * Conversion from a C-131 Samaritan by Kelowna Flightcraft Ltd. in Canada. The CV5800 is a C-131 Samaritan stretched by 14 ft 3 in with the Samaritan's original tail unit rather than the enlarged tail of the CV-580. These conversions also have a new freight door, digital avionics with EFIS and Allison 501-D22 engines in place of the original R-2800 engines.

Military variants

 * Convair C-131 Samaritan
 * The CV-240/340/440 series was used by the United States Air Force for medical evacuation and VIP under this designation


 * Convair T-29 trainer
 * A trainer model of the C-131 was used to instruct navigators and radio operators


 * Convair R4Y Samaritan
 * The United States Navy used the Samaritan under this designation


 * Canadair CC-109 Cosmopolitan
 * Conversion from CV-440, with Napier Eland turboprops in place of the piston engines. The conversions were performed in Canada by Canadair. In Canadian Air Force service they were known as the CC-109 Cosmopolitan. All were re-engined in 1966 with Allison 501-D13 engines.


 * Canadair CL-66
 * Company designation for the CC-109 Eland powered variant

Civilian operators



 * Aero California - CV-340
 * Aerolíneas Argentinas - CV-240 (LV-ADM, LV-ADN, LV-ADO, LV-ADP & LV-ADQ)
 * Aeromexico - CV-340
 * Aeroquetzal - CV-580
 * Air Chathams - CV-580
 * Air Fiji - CV-580
 * Air Freight NZ - CV-580 & CV5800
 * Air Maldives - CV-440
 * Air Resorts - CV-440s that were formerly operated by American Eagle
 * Air Tahoma - CV-240 & CV-580
 * Allegheny Airlines CV-340, CV-440, CV-540 & CV-580
 * American Airlines
 * Ansett Airlines - CV-340, CV-440
 * Arawak - CV-440
 * ARCO Aerolíneas Colonia S.A. CV-240, CV-600
 * Aspen Airways CV-580
 * Aviateca - CV-240, CV 440, 340
 * Bar Harbor Airlines - CV-600
 * Braniff International Airways - CV-340
 * Buffalo Airways - CV-240
 * Cal Sierra Airlines - CV-580
 * Canadian Pacific Airlines - CV-240
 * Central Airlines - CV-240 and CV-600
 * Chathams Pacific - CV-580
 * Conair Group
 * Continental Airlines
 * Caribair - CV-340, CV-640
 * Delta Air Lines - CV-340 & CV-440
 * Desert Air - CV-240
 * Eastern Air Lines - CV-440
 * ERA Aviation - CV-580
 * Finnair CV-340 (converted to CV-440) & CV440
 * Fred. Olsen Flyselskap - CV-340
 * Frontier Airlines - CV-580 and CV-600
 * Garuda Indonesia - CV-240, CV-340 & CV-440
 * Hawaiian Airlines - CV-340, -CV-640
 * IFL Group - CV-580 & CV5800
 * JAT Yugoslav Airlines - CV-340 & CV-440
 * Iberia Airlines - Convair CV-440
 * Kar-Air CV-440
 * Kelowna Flightcraft Air Charter - CV-580 & CV5800
 * Kitty Hawk Aircargo - Convair 640
 * KLM - CV-240 & CV-340
 * LACSA - CV-340
 * Líneas Aéreas Paraguayas (LAP) - 3 CV-240
 * Lake Central Airlines - CV-340 & CV-580
 * Linjeflyg - CV-340 & CV-440
 * LOT Polish Airlines - CV-240 (5 in 1957-1966)
 * Lufthansa - CV-440
 * Metro Airlines - CV-580
 * Mey-Air - CV-240
 * Miami Air Lease - CV-440
 * Midwest Air Charter/Airborne Express - CV-600
 * National Airlines - CV-340 & CV-440
 * Nolinor Aviation - CV-580
 * Nor-Fly Charter - CV-440 & CV580
 * North Central Airlines - CV-580
 * Northeast Airlines - CV-240
 * Northwest Airlines - CV-580
 * Pacific Western Airlines - CV-640
 * Pan American World Airways (Pan Am)
 * Pakistan International Airlines - CV-240
 * Partnair - CV-580
 * Philippine Airlines - CV-340 (1950s-1960s)
 * Pionair - CV-580
 * Polaris Air Transport - CV-240
 * Prinair - CV-580
 * Quebecair - CV-540 (CL-66)
 * Real Transportes Aéreos - CV-340 & CV-440
 * Republic Airlines - CV-580
 * Rhoades Aviaton - CV-640
 * SABENA - CV-240 & CV-440
 * Sahsa - CV-580
 * SAS - CV-440
 * Serviços Aéreos Cruzeiro do Sul - CV-240, CV340
 * Sierra Pacific CV-340, CV-440 CV-580
 * SMB Stage Line - Convair 640
 * Stellar Airfreighter - CV-440
 * Swissair - CV-240 & CV-440
 * Trans-Texas Airways - CV-240 & CV-600
 * Texas International Airlines - CV-600
 * Toa Airways
 * Trans Australia Airlines
 * Transportes Aéreos Nacional - CV-440
 * United Airlines
 * Varig - CV-240
 * Western Airlines
 * Wright Airlines - CV-600
 * Zantop International Airlines - Convair 640

Military operators

 * Australia
 * Royal Australian Air Force - Two CV-440 Metropolitans (RAAF serial A95-313 and 353) were in service with RAAF from 1956 to 1968.
 * No. 34 Squadron RAAF
 * Bolivia
 * CV-440 & CV-580


 * Canada
 * Royal Canadian Air Force/Canadian Armed Forces (Canada) CV-540s were re engined with T56 turbo props with 412 Squadron


 * Colombia
 * CV-580


 * Germany
 * CV-440


 * Italy
 * Aeronautica Militare Italiana CV-440 Metropolitans
 * Paraguay
 * Paraguayan Air Force: CV-440/C-131D
 * Sri Lanka
 * Sri Lanka Air Force - CV-440
 * Mexico
 * Mexican Air Force CV-580 Nowadays used as a AEW&C Simualator on AFB #1 Santa Lucia
 * Mexican Air Force CV-580 Nowadays used as a AEW&C Simualator on AFB #1 Santa Lucia

Other operators

 * USA
 * Federal Aviation Administration
 * Airborne Resources, (C-131B N131CR ))
 * Environmental Research Institute of Michigan, later Veridian and then General Dynamics Advanced Information Systems (CV-580s N51211 and N51255 )
 * Honeywell International, Everett Washington (CV-580 N580AS )
 * National Research Council (Canada) (CV-580 C-FNRC )
 * Raytheon, Tucson Arizona (CV-580 N580HH )
 * University of Washington, (CV-580 N3UW )