Aero: Next generation plane will help change air force pilot training

30-08-2019

For the past five years one of the world’s oldest aircraft manufacturers, Aero Vodochody, has been developing a next generation jet trainer. Engineers say that one of its key selling points is its ability to train pilots from beginning to end, a new concept in how pilots are taught. To find out more, I visited the two sites where tests are underway.

Photo: Ondřej TomšůPhoto: Ondřej Tomšů

Fatigue testing of the L-39NG, photo: Ondřej TomšůFatigue testing of the L-39NG, photo: Ondřej Tomšů On the northern outskirts of Prague lies the Czech Republic’s Aerospace Research Centre (VZLÚ). Its origins strech as far back as 1922, but much of the vast complex was built during the 1980s.

Not much has changed in its outward appearance and to an onlooker it may at first seem like a relic of the past.

However, the facility has adapted to the country’s switch to a market economy. Many of its buildings are now rented by some of the Czech Republic’s leading start-ups, which produce hi-tech wares such as 3D printers, stratospheric balloons and advanced batteries.

The contents of each of these buildings would likely be worthy of interest, but we are headed for the largest one of them all. A testing hall that Daniel Zeman, the man in charge of VZLÚ communications, says is unique in the country.

“We are standing in front of the biggest hall we have here at VZLÚ. Pretty much all Czechoslovak and later Czech planes have been tested here. It is big enough for a whole Boeing 737 to fit in.”

“This building was built in the middle of the 1980s. Its purpose is to develop and test aircraft. Pretty much all Czechoslovak and later Czech planes have been tested here. It is big enough for a whole Boeing 737 to fit in.”

The object we have come to see lies within this building. It is the brand new version of the Czech L-39 jet aircraft, which has been training military pilots in Russia, Europe and the Middle-East since the 1960s.

The new version is called the L-39NG (Next Generation) and it promises to revolutionise air force pilot training says Vojtěch Labuda, the man in charge of the L-39NG programme at Aero Vodochody, the company that built it.

L-39CW, photo: Mossback, Wikimedia Commons, CC BY-SA 4.0L-39CW, photo: Mossback, Wikimedia Commons, CC BY-SA 4.0 “A jet trainer is an absolutely vital element in the air force pilot’s training syllabus. Today, it is standard in the world that students start with a propeller powered aircraft and then after reaching a certain point of their training they switch to training purpose jet aircraft.

“One of the selling points of the L39NG is that it will be an aircraft which provides a fully integrated training platform. That means it can be used for training throughout the pilot’s entire training period.”

A mix of machines, scaffolding and strange sounds are the first things that make an impression as one enters the large hall. In front of it all stands Václav Horák, the man responsible the aircraft’s ongoing static tests which the hall is being used for.

“One of the selling points of the L39NG is that it will be an aircraft which provides a fully integrated training platform. That means it can be used for training throughout the pilot’s entire training period.”

He leads me through the metal, pointing to the floor, which he says is built to support strong forces from loading aircraft.

Finally, we see the plane.

It is not the whole L-39NG. This particular aircraft is missing its cockpit and some of its wing flaps. For good reason, I find out later in his office, because this particular model is destined for destruction through a series of strength tests.

“VZLÚ is currently responsible for the static strength tests of the whole airframe of the L39NG in its flying confutation and parts such as the wing, fuselage and stabiliser. Airplanes suffer various pressures both from the air and from the surface during their service that means we have to test all of the loads and how well [the L-39NG] will perform during operations.”

Václav Horák, engineer at VZLÚ, photo: Ondřej TomšůVáclav Horák, engineer at VZLÚ, photo: Ondřej Tomšů The jet trainer was first presented to the public as a design prototype five years ago. It has a wingspan of just over 9 meters and is nearly 12 meters long. With a basic weight of 3.8 tons, it can carry an extra 2.6 tons in added weight.

In outward appearance, the L-39NG differs very little from its predecessor, the L-39 Albatross, which was developed more than 50 years ago.

However, as Mr. Labuda tells me, this is because of the original design’s excellent aerodynamics.

“We decided not to change as much as possible for the simple reason that the old L39 is a proven and well known plane across the world. In terms of aerodynamics we kept everything. In terms of the internal design, internal structure, the primary and secondary structure and, most importantly, avionics systems, it is a completely new aircraft.”

“In terms of aerodynamics we kept everything. In terms of the internal design, internal structure, the primary and secondary structure and, most importantly, avionics systems, it is a completely new aircraft.”

Back in Mr. Horák’s office, the old VZLÚ engineer agrees and says that Aero designers have always been good at what they do.

“Given that I have worked for many years in the VZLÚ’s strength testing facility I can say that Aero aircraft have very good designs and Aero Vodochody has very good engineers. They are able to facilitate the overall designs of aircraft for future designs and development.”

As we discuss aircraft the conversation moves to another aspect of testing, the science of examining aircraft resistance to bird impacts.

When they take place during real flights, they can cause catastrophic damage to planes, such as was very nearly the case earlier in august, when a flock of gulls smashed into a Russian Airbus 321’s engines, causing them to catch fire.

A test in VZLÚ, photo: M.podaril, Wikimedia Commons, CC BY-SA 3.0A test in VZLÚ, photo: M.podaril, Wikimedia Commons, CC BY-SA 3.0 Mr. Horák says that when it comes to Czech planes, tests are usually conducted in one of VZLÚ’s buildings.

“We simulate these impacts by using a freshly killed chicken and are able to use between 4 to 8 pounds. There are many examples of catastrophic impacts from birds and other objects, so it is of course necessary.

“We are not able to simulate the impact of a whole flock of birds. Rather we test specific parts of the plane such as the windows, leading edges, engine inlets and more on how they would react to bird impacts, or the being hit by other objects in the air and on the surface.”

Our discussion on the rather macabre topic suddenly ends however, when I am invited by Aero Vodochody to visit their plant, which lies close to the nearby town of Odolena Voda.

Tobiáš Tvrdík, photo: Ondřej TomšůTobiáš Tvrdík, photo: Ondřej Tomšů The short trip is brought to a halt at Aero’s reception, where a thorough security check takes place.

Security is necessary because Aero’s manufacturing plant is also an airport and its hangars contain planes that are being serviced for various clients.

The company spokesman Tobiáš Tvrdík says that some these hangars have been holding planes since the First Republic period, as Aero has been in existence since the early days of aviation.

“Aero Vodochody is the oldest Czechoslovak aircraft manufacturer and it is actually one of the oldest in the world. Not many companies can boast about such a history.

Photo: Ondřej TomšůPhoto: Ondřej Tomšů “It may be a coincidence but actually the first plane we ever designed was a training aircraft, so you could say we defined our segment from the very beginning. Later we also produced bombers and civilian aircraft, such as the Aerotaxi AE45, which is also quite famous.”

In its 100-year history, Aero has produced around 11,000 aircraft. Out of these more than six thousand were jet aircraft. The knowledge required to design jet planes was acquired during the Communist era, when the Soviet Union gave Aero the license to produce its MiG 15s.

“If we speak about our jet trainers, their history started in the 1950s. Back then we produced more than 3,000 MiG-15s under a license and based on this experience we developed our first jet aircraft which was the L29 Delfín of which we produced more than 3,000. The L39, which I believe is the most successful jet trainer in the world, was designed by Jan Vlček during the 1960s and nearly 3,000 planes of this model were built.”

“Our strategy now is to become a proprietary aircraft producer and the L39NG is seen as a product that could help us do that.”

When the Iron Curtain disappeared in 1989, so did many of Aero’s contracts guaranteed by socialist central planning, but the company has since managed to adapt, says Mr. Tvrdík.

“Those years were quite tough, but nowadays we have three pillars of our business that were developed in the past 30 years. One is proprietary aircraft, the L39NG and L159.

“The second one is the aero structures business. That means delivering products to our clients such as Airbus and Embraer. “The third is maintenance and repairs of current aircraft. There are still around 600 L39’s in service, so providing maintenance for these planes is still one of the potential roles for our business. “Our strategy now is to become a proprietary aircraft producer and the L39NG is seen as a product that could help us do that.”

Photo: Ondřej TomšůPhoto: Ondřej Tomšů A lot is at stake for Aero. It has pursued the L-39NG as its main design since 2014 and is hoping to bring in a lot of revenue by offering it as a next generation replacement to the many air forces across the world that are currently using its predecessor, the L-39 Albatross.

The new plane is set to be certified by the end of 2020 after which it will enter service. There are already two agreed contracts. The Czech Airforce has purchased four planes for pilot training, while that of Senegal has bought a further four planes to be configured for light-combat roles.

Although a jet trainer by design, the L-39NG can also serve in combat.

A further potential buyer, Portugal’s SkyTech, has signed a letter of intent with Aero and the company is also looking for buyers in Asia and East Central Europe.

Vojtěch Labuda, L-39 programme lead at Aero, photo: Ondřej TomšůVojtěch Labuda, L-39 programme lead at Aero, photo: Ondřej Tomšů Programme lead Vojtěch Labuda, who is supervising ongoing fatigue tests on another L-39NG, tells us the high expectations are based around three key selling points.

“The first is the platform, a legacy of the old L-39. Second, it is to provide a state of the art modern philosophy of future military pilot training syllabus which will be based on so called flyby events. Finally, the L-39NG as an aircraft and project in general will be massively supported by an integrated logistics system, including a very wide range of ground training devices. That means cockpit procedure, desktop trainer, and full flight simulator up to mission training centre.”

When asked about how the tests have been going so far, he smiles.

Exhibition about Aero’s 100 year history at the National Technical Museum in Prague, photo: Czech TVExhibition about Aero’s 100 year history at the National Technical Museum in Prague, photo: Czech TV “Very, very precise results for everything we have tested so far, exactly as predicted. I would say that everything is on track and we didn’t have any surprises, which surprises me [laughs].”

Those interested in seeing the L-39NG when it is first unveiled to the public will have the opportunity at next month’s NATO Days army and air force show, which are taking place on September 21 and 22 at the Mošnov airport near Ostrava.

If you are curious about finding more about Aero’s 100 year history, a special exhibition, which features Aero’s aircraft and even cars, is currently running at the National Technical Museum in Prague until November 17.

30-08-2019