The CASA/IPTN CN-235 is a medium-range twin-engined transport plane that was jointly developed by CASA of Spainand Indonesian manufacturer IPTN, as a regional airliner and military transport. Its primary military roles include maritime patrol, surveillance, and air transport. Its largest user is Turkey which has 61 aircraft.

Design and development
The project was a joint venture between Construcciones Aeronáuticas SA (CASA) and Indonesian Aerospace (PT. Dirgantara Indonesia), formerly known as IPTN, which formed Airtech to manage the programme. The partnership applied only to the Series 10 and Series 100/110, with later versions being developed independently. Over 230 of all versions of CN-235 are in service and have accumulated more than 500,000 flight hours.

Design began in January 1980 with first flight on 11 November 1983. Spanish and Indonesian certification was on 20 June 1986; the first flight of the production aircraft was on 19 August 1986 and FAA type approval was granted on 3 December 1986. The aircraft entered service on 1 March 1988

In 1995, CASA launched development of a stretched CN-235 as the C-295. In December 2002, the Colombian Navy ordered two CN-235 for patrol and anti-drug trafficking missions.

In April 2005, Venezuela ordered two CN-235 maritime surveillance aircraft plus 10 transport planes but the operation was halted because the United States government refused to allow the transfer of what they deemed to be US technology in the avionics.

In January 2006, Thailand placed an order with Indonesian Aerospace for ten aircraft, six for the Ministry of Defence and four for the Ministry of Agriculture.

In December 2007, Spain ordered two CN-235 maritime patrol aircraft for the Guardia Civil, for delivery 2008–2009.

One CN-235 MPA aircraft was delivered by Indonesian Aerospace to the Indonesian defence ministry in June 2008.

In August 2006, three CASA CN-235-10 aircraft remained in airline service, in Africa, with Safair (two) and Tiko Air(one). Asian Spirit operated a lone CN-235-220 in the Philippines, correct as of June/July 2007.

The Irish Air Corps operates two CASA aircraft for maritime patrol duty.

There are at least two CN-235s flying with the United States Air Force for an undisclosed role with the 427th Special Operations Squadron, located at the former Pope AFB, North Carolina.

In early July 2008, the Mexican Navy announced that it would purchase six CASA CN-235s from Spain. In April 2010, Hervé Morin, French Minister of Defence, announced the order of eight CN-235-300s from Spain.

In 2011, Indonesian Aerospace was still working on 4 CN-235-110 MPAs for South Korea Coast Guard with amount of $96 million.

The Senegalese Air Force acquired two CN-235s in 2010 and August 2012 under a $13 million contract. They plan to buy two more aircraft for VIP and cargo duties. The Air Force is also interested in the maritime patrol version of the aircraft.

Variants
CN-235-10
Initial production version (15 built by each company), with GE CT7-7A engines.

CN-235-100/110
Generally as series 10, but with GE CT7-9C engines in new composites nacelles; replaced Series 10 in 1988 from 31st production aircraft. Series 100 is Spanish-built, series 110 Indonesian-built, with improved electrical, warning and environmental systems.

CN-235-200/220
Improved version. Structural reinforcements to cater for higher operating weights, aerodynamic improvements to wing leading-edges and rudder, reduced field length requirements and much-increased range with maximum payload. Series 200 is Spanish-built, Series 220 Indonesian-built.

CN-235-300
CASA Modification of 200/220 series, with the Honeywell International Corp. avionics suite. Other features include improved pressurisation and provision for optional twin-nosewheel installation.

CN-235-330 Phoenix
Modification of Series 200/220, offered by IPTN with new Honeywell avionics, ARL-2002 EW system and 16.800 kg/37.037 lb MTOW, to Royal Australian Air Force to meet Project Air 5190 tactical airlift requirement, but was forced by financial constraints to withdraw in 1998.

CN-235 MPA
Maritime patrol version with 6 hardpoints to carry AM-39 Exocet-Missiles or Mk.46-Torpedos.

HC-144 Ocean Sentry
United States Coast Guard designation for a planned twenty-two
aircraft fleet bought to replace the small HU-25 Guardian business-style jets. As of 2010, twelve  had been delivered.