Written 2000

I was visiting the AFM stand at Farnborough 2000 when John Barker asked me if I would like to meet the Sukhoi SU-29 pilot: Vytautas Lapenas.  I had watched his impressive display the day before and was keen to meet him.  I followed John not really understanding the relevance of the person I was going to meet.  First of all, I was introduced to Ramunas Vyzintas, the Director of the training school that Vytautas and the Lithuanian company AviaBaltika Aviation had established to train and promote aerobatic excellence in their country.  He gave me some background on Vytautas and the training school in general.  It was only then that I realized that the pilot's background was more amazing than the aircraft that he was displaying.


VYTAUTAS LAPENAS  (back to top)

Vytautas started flying at the age of 17 and by the age of 22 he had become the Lithuanian aerobatics Champaign.  When he turned 27 (1985) he won the Soviet Union Championships and three years later he made his debut at the World Championships, winning a silver medal in the team event.  However, on the 19 September 1989 he was very badly injured during a high-speed accident into some trees, while displaying a Yak-55.  In the awful crash Vytautas lost his left leg, fingers on his left hand and almost half of his body suffered burn injuries.  For any normal person that would have been the end of an extremely promising aerobatic flying career.  Remarkably, he was kept alive and with great strength of character he struggled to regain his past life.  After several months he again learned to walk, climb stairs, drive a car and eventually, with tremendous will power, to fly again.  Not content with just flying again he battled to return to competition aerobatics.  Six years after the accident he made his second debut at the Lithuanian championships and won!  Later, when chatting with him, I could see that he had a tremendous love of life and it was with this strength and energy that he wanted to give back something for all the good things that he had experienced.  He explained that this is why he had established an aerobatic school of excellence.  Somewhere that budding aerobatic pilots could go to learn their art form.  Having not been to the school to participate in the training I can only surmise what the standards would be like from watching Vytautas fly and by the enormous respect I have for him having met him in person.  He is without doubt an inspiration to us all.


SU-29 FAMILIARIZATION  (back to top)

Having chatted with Vytautas for several hours about his adventures, his plans for the training school and how 'great' his latest mount, the SU-29, was for modern aerobatics. He offered me the chance of a familiarization flight in the aircraft.  I have to say I was in two minds whether to accept having seen his display the day before.  However, this hesitancy lasted about two and a half seconds before I calmly accepted the offer!

The first thing that was needed was a good brief on the aircraft.  Vytautas explained that the aircraft would be like nothing that I had flown before.  Firstly, it was stressed to plus 10 g and minus 9 g.  This meant that it was possible to manoeuvre the aircraft during a very tight turn where the stresses on the body would make you feel ten times heavier, or if inverted doing the same sort of turn nine times lighter, with you eyes trying to pop out of their sockets!  I must have looked a little concerned at the high-g capability because he said "don't worry the aircraft structure is built to withstand g-loadings of 22.9 times the force of gravity" - I think this made me feel a bit happier?!  This capability combined with a very light weight (maximum take-off weight is only 1450 kilograms/3197 pounds), a large 260 horse power engine and an extremely large 2.6 metre propeller gave it more than enough capability and power for anything that I wanted to do.  He explained the systems, which were all very simple, and said that the aircraft could hold 270 litres of fuel, with a fuel consumption in the cruise (250 kph) of 60 litres per hour.  Even at display power settings the consumption only increased to 100 litres an hour.


Aerobatic Design  (back to top)

One interesting design feature of the aircraft was the shape of the wing.  Most aircraft wings are designed to produced more lift on the top surface than on the bottom surface.  These 'cambered' wings are designed to optimize the cruise capability of the aircraft.  In an aerobatic machine, which spends as much of its time inverted as the right way up, efficiency is not measured in the same way.  Indeed, it is beneficial for the wing to be designed to fly as well whichever way up the aircraft is.  Hence, the wing section on the SU-29 is symmetrical, meaning that it produces the same amount of lift whichever way up it is.  This was proved true during my flight where I stalled the aircraft in the normal way and then again inverted and the stall speeds were the same at 115 kph!


TIME TO FLY  (back to top)

Vytautas explained that because of the late timing of his display slot at Farnborough, I would be flying with the equally capable 'Leo' Leonas.  He was similarly enthusiastic about the aeroplane and gave me a good cockpit briefing.  Inside was very basic and it looked liked it was built to be strong and rugged for the aerobatic world.  This was further demonstrated by the harness system, which, once strapped in, had a ratchet mechanism on it to 'tighten down' the straps to ensure no body movement off the seat, even during the most severe aerobatic manoeuvres!  The cockpit itself was not labelled in English but was reasonably self explanatory and well laid out.  The 'g' meter was slightly confusing because it worked in the opposite sense; ie, positive g values were indicated by the gauge needle moving anticlockwise (down) from the straight and level nine o'clock position and vice versa for the negative g values.  I was told that this was because the aircraft spent the majority of its aerobating life inverted - by now I was really looking forward to the flight!

Once the aircraft was started, the large propeller gently rocked the whole machine, rather like a very high performance racing car.  Taxying was easy using differential braking via the rudder pedals but a gentle weave was required as the visibility directly forward was reasonably poor, as with all large-engined taildraggers.  When cleared for take-off I manoeuvred the aircraft into position and locked the tailwheel.  This capability is an excellent feature for a taildragger and greatly reduces the potential for ground looping (uncontrollable turns on the ground) during the take-off or the landing.  As power was applied the engine roared into action with a harsh growl.  It was not as smooth as its Western equivalents but it sounded like it meant business.  The torque of the engine trying to pull the aircraft's nose away from the runway's centreline was easy to control with moderate amounts of rudder being applied.  The extra airflow from the 'prop-wash' of the large propeller meant that the tail could be lifted very early during the take-off roll.  Acceleration was good and we lifted off at about 120 kph.  Immediately, the sensitivity of the aircraft hit me.  It was extremely twitchy in all axes and the forces needed to move the stick were very light.  The light forces took some getting used to but by the time we reached the manoeuvring area I was more at ease with the smallness of the stick inputs required.  This really was an aircraft that needed a light touch to prevent unwanted oscillations from developing.

My first exploration of the aircraft was to stall the machine at idle engine power.  This was very benign, unlike the consequences of stalling with power on, where the aircraft tended to torque roll at the stall.  However, the spinning characteristics were again benign, even if the rate of rotation was reasonably high.  The speed in the spin stabilized at 115 kph and the height loss was only about 200 metres per turn.  When the recovery was initiated the spin stopped almost immediately, which is very important for an aerobatic aircraft where spin manoeuvres often make up parts of the display routine.  When I was comfortable with the spin characteristics and the recovery techniques I felt safe to move on to the basic aerobatics.  These were all very simple, with the loop starting at 300 kph and rolling manoeuvres at 200 kph. Stall turns were a dream to fly with the rudder being inputted at 50 kph going up in the vertical.   The only negative area was that you needed to be very careful not to 'pull' too hard during the manoeuvring.  Because the control forces required were so light is was easy to pull slightly too hard, which would cause high-g buffeting or stalling.  I would have preferred the control forces to have been higher, which would have helped me to control the aircraft better during extreme manoeuvring.  However, Leo explained that it was something that you get used to and that you could not pull enough g to break the aircraft - that at least was very reassuring!

Once I had tried the basic aerobatics I asked Leo to show me what the aircraft could do - that was a mistake.  I spent the next five minutes not knowing which way was up or what we were going to do next!  This was not helped by the lack of a fully common language and my helmet, which had just decided to play-up.  Once the onslaught was over I managed to ask for a demonstration of one manoeuvre at a time.  The first was the flick roll, which was entered at approximately 170 kph and involved full use of the rudder, aileron and forward stick in the same direction using a snap movement of the controls.  The rate of 'flick' of the flick roll was devastatingly fast and I could understand why Vytautas' display looked so good.  Even doing the manoeuvre myself it was over in an instant - very impressive.


Home Leg  (back to top)

Unfortunately, by the time I had sorted out my helmet and had received some flick-roll tuition, Farnborough was about to close and we had to rush home sooner than I would have liked and before I could get a full picture of the aircraft's capability.  Back in the circuit downwind was started at 200 kph, with very little else to do as the aircraft has a fixed undercarriage and no flaps.  The speed round finals was reduced to 170 kph with the engine just ticking over.  Visibility was generally good until the very last stages of the touchdown, as the speed was further reduced to 150 kph.  Because of the undercarriage design the actual landing needed careful judgement to prevent a 'springy' bounce back into the air!

The flight was too short to perform a good assessment of the aircraft but it did give me a taste for what it could do and perhaps a better understanding of why Vytautas was so full of life and energy.  It would be difficult to be any other way performing the aerial gymnastics that he manages to perform in this very rugged little aircraft.