Learjet 35/36

Updated: October 2026 – A small, slender jet passes over the fields of Schleswig-Holstein with a bright whine, thick tanks hanging at the wingtips and pods under the wings that you would not expect on any business travel jet. That is almost certainly a Learjet 35 or 36 of GFD – out to play an adversary for the Air Force, Army or Navy. Here you learn how to recognize this business jet classic, what separates the 35 and 36, and why the type is known in Germany above all as an aerial target aircraft.

What is the Learjet 35/36?

The Learjet 35 is a twinjet business jet for up to eight passengers and two pilots. It was developed and built by Gates Learjet in Wichita, Kansas. The name goes back to Bill Lear, who brought the first Learjet to market in the 1960s and thereby practically invented the segment of fast, small business travel jets. In 1990, Bombardier took over the Learjet brand, which is why the type is usually filed under Bombardier today – even though the 35 and 36 came into being long before that takeover.

Technically, the Learjet 35 is a further development of the Learjet 25. Its turbojet engines were thirsty and loud. Learjet therefore tested a converted 25 from 1971 with a new Garrett turbofan on one side and the old engine on the other. That became a type of its own with a slightly longer fuselage and greater wingspan, at first still designated the Learjet 26. The prototype of the Learjet 35 flew on August 22, 1973, and in July 1974 the US aviation authority FAA certified the Learjet 35 and the Learjet 36 together.

In 1976, the improved versions 35A and 36A arrived with more powerful engines and a higher takeoff weight. They make up the bulk of the fleet built. Production ran until 1994. How many aircraft were built in total depends on how you count: reference works give figures between about 675 and about 740 aircraft for the whole family. Either way, the type is among the most-built business jets of its time.

Learjet 35 or 36: the difference

The two versions are twins with a different division of roles. The airframe, the engines and the cockpit are the same. The difference lies in the fuselage: the Learjet 36 has a significantly larger fuel tank, which increases the range by several hundred kilometers. In exchange, the passenger cabin is about 45 centimeters shorter. Instead of up to eight, only up to six passengers fit in.

Feature	Learjet 35/35A	Learjet 36/36A
ICAO type designator	LJ35	usually also LJ35
Certification	1974 (35A from 1976)	1974 (36A from 1976)
Passengers	up to 8	up to 6
Fuselage tank	standard	enlarged
Range	shorter	significantly longer
External appearance	practically identical	practically identical

For spotters, that means: from the outside you can hardly separate the 35 and 36. The registration and a database settle it. By the way, for its own aircraft GFD states a maximum range of about 1,700 nautical miles for the 35A (about 1,900 with enlarged tip tanks) and about 2,100 nautical miles for the 36A.

How to recognize the Learjet 35/36

The Learjet 35 is one of the business jets that, with a bit of practice, you recognize from a long way off. Three checks are usually enough.

Together with the type designator LJ35 in the tracking service, the identification is then unambiguous. Whether it is a 35A or 36A, only a registration lookup shows. How that works is explained in Tracking an aircraft by registration.

The Learjet 35 at GFD: adversaries on demand

In Germany, the Learjet 35 is known above all through GFD GmbH, formerly Gesellschaft für Flugzieldarstellung (company for aerial target services). The company belongs to Airbus Defence and Space and has its headquarters and flying base at Hohn Air Base in Schleswig-Holstein. Its job: it simulates aerial targets so that soldiers can practice dealing with approaching aircraft and missiles.

The history goes back further than the company itself. As early as 1966, Condor, then a Lufthansa subsidiary, took over aerial target simulation with jets – at first with Canadair Sabres from Sylt, from 1974 with Fiat G.91s. In 1976 the operation moved to Hohn. In 1989, Condor and Aero-Dienst Nürnberg founded GFD, which switched to the Learjet 35 and 36. One Learjet could take two towed targets instead of only one. A long-term contract with the then Federal Office of Defense Technology and Procurement let the fleet grow from 1997, and in 2002 EADS took over the company.

What the Learjets do today is described by GFD itself like this:

• Towed targets: Winches under the wings pull hard and soft targets behind them on cables up to 6.5 kilometers long. Air defense on land and at sea fires at them with guns and guided missiles.
• Electronic warfare: With jammers and decoys under the wings, the jets fly missions in which radar and radio systems are jammed – training under realistic conditions.
• Threat simulation: A pod developed in-house emits the signatures of real or generic radars and thus simulates approaching aircraft or missiles, also as profiles for attacks on ships.
• Red Air: In exercises, the Learjets play the adversary for fighter aircraft like the Eurofighter Typhoon.
• Flight inspection: On top of that come survey flights at Bundeswehr airfields as well as jobs for authorities, industry, NATO partners and research institutions.

The fleet size has changed over the years. GFD states 16 Learjets of the 35A and 36A types on its website; a reference work listed a total of 14 aircraft as of May 2023. The aircraft carry German registrations of the weight class D-C…, and on the radio and in tracking you recognize them by the callsign KITE. How the German registration classes are structured is explained in German aircraft registrations.

Military Learjet 35s worldwide

It is not only GFD that relies on the Learjet. Its combination of speed, ceiling and manageable operating costs makes it interesting for armed forces.

• USA: From 1984, the US Air Force received Learjet 35As under the designation C-21A. The jets serve as liaison and transport aircraft and can be equipped for medical evacuation. The once-large fleet shrank considerably; in 2019 there were still 19 aircraft on strength. The US Navy also used individual Learjet 35/36s.
• Japan: The Japanese naval air arm flew six U-36As as training and utility aircraft. The last one was retired in March 2025.
• Europe: The Finnish Air Force operates a few Learjet 35s. In Sweden, civil companies such as Swedair flew Learjets as target tugs from the 1980s.
• Latin America: The Brazilian Air Force flies several Learjet 35s, and individual aircraft also serve or have served with the air forces of Argentina, Chile, Peru and Uruguay.

Military Learjets are often only partly visible in tracking services. How to find them anyway is covered in Tracking military aircraft online; why some positions only show up via multilateration is explained in MLAT explained simply.

Risk of mix-ups: family and competition

The Learjet 35 has many relatives and a few competitors in the same size class. The finder helps narrow it down.

The Learjet 45 and the Learjet 75 have a taller, rounder fuselage and winglets, while the Learjet 60 is much longer. The HS 125 or Hawker 800 looks burlier and does not have the horizontal stabilizer at the very top. The Citation Excel/XLS carries its horizontal stabilizer low on the tail. And the Dassault Falcon 20 – likewise a classic in target simulation and special missions – is larger and has a swept wing without tip tanks. An overview of the features of all the big families is given by the guide Telling business jet types apart.

Where you come across the Learjet 35/36

GFD Learjets take off from Hohn but operate wherever exercises are held – over the North Sea and Baltic Sea, over military training areas and around the Eurofighter units. An air base is not a visitor airport: photograph only from publicly accessible areas and observe the rules in Photographing military airfields. Open days offer good opportunities, as described in the article Bundeswehr Day and Air Force open days. Where the Eurofighters the Learjets train with fly is covered in Spotting Eurofighters in Germany; one of the locations is the jointly civil-used Rostock-Laage Airport.

Civil Learjet 35s today fly mainly as air ambulance and charter jets. You meet them where business travel and ambulance traffic come together:

• In northern Germany at Hamburg Airport with its observation deck and at Bremen Airport with its observation deck.
• In the Rhineland at Cologne Bonn Airport, where the observation deck offers a good view of business traffic.
• At the big business jet hubs Geneva with its observation deck and Paris-Le Bourget.

Location	Chance of a hit	Why
Around Hohn / exercise areas in northern Germany	medium	GFD home base, missions according to exercise schedule
Geneva, Paris-Le Bourget	medium	lots of business jet traffic, older jets are getting rarer
Hamburg, Bremen, Cologne Bonn	low to medium	occasional air ambulance and charter flights

Photo tips for the Learjet 35/36

General tips on business travel jets can be found in the guide Spotting business jets.

Common mix-ups and how to rule them out

Conclusion

The Learjet 35/36 is a business jet from the 1970s that has lasted surprisingly long. Tip tanks, T-tail and a slender fuselage make it easy to recognize, the type designator LJ35 confirms the family, and the registration settles whether it is a 35A or 36A. In Germany, the type has a special role: as GFD’s aerial target aircraft from Hohn, it has played the adversary for air defense and fighter pilots for decades. Anyone who catches a KITE Learjet with pods under the wings has a sighting that not everyone has in their hangar.