10 Interesting airliners turned into military aircraft

10: Focke-Wulf Fw 200 Condor

The journey took 24 hours and 55 minutes, at an average speed of 164 mph (264km/h). This mastery of the Atlantic would later be used for far less peaceful reasons.

It would take a much darker role in the Second World War, being described by Churchill (perhaps apocryphally) as the ‘scourge of the Atlantic’; it did much to disrupt vital supplies to the Allies. In what was essentially a hastily converted airliner, the Germans sank over 300,000 tons of shipping in less than a year. This modern but fragile machine proved alarmingly effective thanks to the excellent range.

The Fw 200 also acted as a personal aircraft for senior German leaders; Adolf Hitler (pictured), SS chief Heinrich Himmler and armaments minister Albert Speer each had one at their disposal, among other people.

9: Douglas C-47/DC-3

The most successful and longest-lived tactical transport aircraft began as an airliner, the DC-3, developed in the mid-1930s. At the beginning of the Second World War, it was adapted (with minor modifications) into a military transport aircraft and designated the C-47. Over 95% of the airframes built were these military versions.

During the decade of C-47 production, several engine variants were used without significant changes to the type or size of the engine. The original DC-3 was powered by the 9-cylinder Wright R-1820 Cyclone 9 producing 1,000 horsepower. The C-47 mainly used the 14-cylinder Pratt & Whitney R-1830 Twin Wasp which produced 1200 horsepower.

9: Douglas C-47/DC-3

Roughly 33% of the US-built aircraft was the C-47B variant. This aircraft used Pratt & Whitney R-1830-90 engines with a high-altitude two-speed supercharger. This 1942 modification was critical for the China-Burma-India supply routes and allowed the aircraft to carry a full payload over the 15,000-foot mountain passes.

The AC-47 Spooky (pictured), a ferocious gunship born from the C-47, unleashed hellfire during the Vietnam War. Bristling with guns, this airborne beast roared through the night, raining thousands of rounds per minute on unlucky enemy positions. Its struck fear into those facing its withering precision firepower.

8: Airbus A330 MRTT

The European Airbus A330 is a dependable wide-bodied airliner that first flew in 1992. It’s a large twin-engine machine weighing up to 242,000 kg (534,000 lb). It proved a smash hit with airlines and has proved equally adept as a military transport and refuelling tanker.

Though often overlooked, the tanker or refuelling aircraft is vital to every major air force. Topping up fuel while on the go massively increases the reach and effectiveness of an air force. The most impressive of these flying ’gas stations’ is likely the European Airbus A330 MRTT.

8: Airbus A330 MRTT

Airbus A330 MRTT (Multi-Role Tanker Transport) lives up to its designation; it is probably the best air-to-air refuelling aircraft in the world, and so much more. It can refuel anything thanks to both drogue pods and a boom (the two systems used to refuel aircraft) and can do it anywhere, thanks to a robust defensive countermeasures suite, and can do it while carrying cargo and/or passengers.

The A330 MRTT can carry an impressive 111 tons of fuel in the tanker role. In the medevac role, it can carry 130 patients on stretchers. In the transport role, it can carry 300 soldiers. It is operated by the air forces of Australia, Brazil, Canada, France, the Netherlands, the United Arab Emirates, the United Kingdom, Italy, Saudi Arabia, Singapore, Spain and South Korea.

7: Boeing 737

The Boeing 737 is a familiar sight to almost anyone who has travelled by air. The 737 first flew in 1967 and since then has become the most successful jet airliner in history. It’s the world’s best-selling commercial jetliner, with over 12,030 delivered and 16,805 ordered as of March 2025.

At any given time, there are an estimated 1,250 737s in the air, and a 737 takes off roughly every five seconds somewhere in the world. The fleet has accumulated over 119 billion miles and carried nearly 17 billion passengers. But despite its reputation for jolly air travel, it also performs several deadly roles, armed and kitted out for the fight.

7: Boeing 737

The most potently armed member of the 737 family is the P-8 Poseidon. The Poseidon, named for the Greek god of the seas, is a maritime patrol and reconnaissance aircraft. It is used by the United States, India, Norway, Australia, New Zealand, South Korea and the United Kingdom.

It is equipped with special sensors, some of which can hunt down submarines. It can be armed with a bewildering array of weapons, including torpedoes, cruise missiles, mines and depth charges. Other military 737s include the Boeing E-7 Wedgetail, which carries a giant radar for the airborne early warning and control role.

6: de Havilland Comet/Nimrod

The UK is largely surrounded by water: to the south by the English Channel, to the east by the North Sea, to the west by the Irish Sea and the Atlantic Ocean. Defending submarines, saving drowning sailors, reconnaissance, tracking hostile vessels, and protecting resources all require a maritime patrol aircraft, and the UK had one of the best, based on the world’s first jet airliner, the de Havilland Comet, the Nimrod.

In 1982 Nimrods escorted the British Task Force as it sailed towards the Falklands, providing search and rescue as well as acting as communications relay in support of the Operation Black Buck Vulcan raids. Nimrod MR2s stood guard against attacks from Argentinian submarines. Equipped with AIM-9 Sidewinder missiles to hunt Argentinian reconnaissance aircraft, they also became perhaps the largest and heaviest ‘fighter’ ever built.

6: de Havilland Comet/Nimrod

Nimrods carried out long reconnaissance missions, including a 19-hour patrol which passed within 60 miles (97 km) of the Argentine coast to check that Argentine ships were not at sea. On the night of 20/21 May, one mission took a Nimrod 8453 miles (13,604 km), the longest distance flight carried out during the Falklands War.

The Comet itself was also vitally important for both its military transport role, and its shadowy work for No. 51 Squadron (as both the Comet and the Nimrod). According to one anonymous defence source we spoke to, ‘I’d consider the Comet and Nimrod aircraft of 51 Sqn to be the most important RAF Cold War reconnaissance asset, and I’m not at liberty to discuss why.’

5: HFB 320 Hansa

The West German HFB 320 Hansa Jet first flew in 1964, featuring an unusual forward-swept wing. This innovative design was previously seen on the Junkers Ju 287, a jet bomber developed late in the second world war created by the Hansa Jet’s designer, Hans Wocke. The configuration contributed to its distinctive appearance and performance.

Hamburger Flugzeugbau (HFB) launched the Hansa Jet project in response to the American Learjet 23’s success. Aimed at the business and military transport market, the Hansa combined Cold War-era elegance with unconventional engineering. With its sleek design and unique wing layout, the aircraft gained a cult following for its avant-garde style.

5: HFB 320 Hansa

In 1963, the German Luftwaffe ordered Hansa Jets for VIP transport duties. Additional aircraft were procured between 1976 and 1982 for electronic countermeasure (ECM) training missions. By 1985, the Hansas began to be replaced by Canadair Challengers in VIP roles, though Electronic Counter Measure variants remained in service until 1994.

Only 47 HFB 320s were ever produced, and the type had quite a bad safety record. This did not stop the aircraft’s sleek profile and rare forward-swept wings making it a memorable, and loved, symbol of Cold War innovation and West German aerospace ambition.

4: Sud Aviation SE 210 Caravelle

Unbearably beautiful, featuring a wealth of innovations and capable of recording gypsy jazz singles in flight, there are many reasons why the Caravelle was a technological tour de force that inspired love in those that came close to the French jetliner.

Whereas competitors had engines in or under the wings, noisily close to most areas of the cabin, the Caravelle’s two engines were neatly tucked away in nacelles at the rear end of the aircraft. It was said that the noisiest seat on board the Caravelle was only as loud as the quietest seat in the quietest rival airliner.

4: Sud Aviation SE 210 Caravelle

To demonstrate this quietness, guitarist and singer Sacha Distel, accompanied by his orchestra, took a trip aboard the Caravelle III Alsace to record a single inside the aircraft on 17 April 1959. In addition to musical instruments – including a 200kg piano– a recording studio was installed. The recording was started at 10,500 metres altitude.

The Caravelle proved extremely popular as both a governmental and military transport, serving around the world in nations that included France, Mexico, and Rwanda. It found a sneaky role in Swedish Air Force service; two ex-SAS aircraft designated TP 85 were used as electronic intelligence aircraft from 1974–1998.

3: Lockheed Constellation

The Lockheed Constellation, first flown in 1943, was a revolutionary airliner. With its sleek dolphin-shaped fuselage and triple-tail design, it became a symbol of luxury air travel in the 1950s. TWA and Pan Am were among the primary operators of this long-range, pressurised aircraft.

The Constellation was praised for its speed, comfort, and range. Capable of crossing continents and oceans, it redefined commercial aviation. Its pressurised cabin allowed for higher altitude flights, avoiding turbulence and improving passenger comfort. The elegant design and smooth performance earned it admiration from both pilots and passengers worldwide.

3: Lockheed Constellation

Military variants of the Constellation included the C-69 transport (which, through a quirk in history, entered service before the airliner) and VC-121 VIP aircraft, notably used by President Eisenhower. Most significantly, the EC-121 Warning Star (pictured) served as an airborne early warning and control (AEW&C) aircraft. Developed during the Cold War, it provided radar surveillance and extended early warning capabilities far beyond ground-based systems.

The EC-121 featured a large radar and electronic surveillance gear. It was instrumental in monitoring Soviet activity and guiding fighter intercepts. During the Vietnam War, it provided critical radar coverage and battle management. EC-121s were vital in advancing airborne command and control, laying the groundwork for modern AWACS aircraft. Another charismatic offshoot was the Indian Navy’s search and rescue Super Constellation.

2: Vickers VC10

The distinctive Vickers VC10 was an excellent British airliner that first flew in 1962. It featured many modern innovations and, for a while, boasted unique performance. Though superb, it was not the most economical or flexible airliner, and only 54 were built.

The VC10 was one of the fastest airliners this side of Concorde and the Tu-144. Its ‘never exceed speed’ was a spritely Mach 0.94. There is a story of a medical emergency onboard a VC10 en route from South Africa being addressed with an FL430 flight at a hair-singeing Mach 0.95. This would have even given the speedy Convair of Elvis Presley a run for its money…

2: Vickers VC10

Sublimely uncluttered aerodynamic cleanliness define the appearance of this lovely airliner. Modern airline engines are too big to be put at the back, but this wasn’t the case in the VC10’s time (to be fair, there are other issues with having the engines on the back), and the VC10 had a neat quartet of jets tucked beneath the tail.

Before it had even flown, Vickers had considered military versions. These ranged from ballistic missile carriers bristling with massive weapons, to maritime patrol aircraft, and even Airborne Early Warning aircraft equipped with huge radars. While none of these materialised, the transport and tanker variant did reach service with the Royal Air Force (eventually) and proved brilliant in this role.

1: Tupolev Tu-116

With the death of Stalin, the ‘Khrushchev Thaw’ left the Soviet Union in the tricky position of wanting to engage with the wider world but with no indigenous way of getting there. Fearing that mating an airliner fuselage to the wings of a Tu-95 nuclear bomber to make the Tu-114 would take more time than was available before a 1959 state visit to the USA, a less ambitious backup plan was made.

The Tu-116 replaced the Tu-95’s bomb bays with a passenger compartment for the head of state and his entourage; in a prescient nod to post-9/11 security arrangements, it was impossible to access the cockpit from the passenger compartment, messages being passed by pneumatic tube.