Here’s a translation of the full report by Sebastian Kawa after his first flight in the GP14SE Velo.
The most joyful thing is the fact, that everything Grzegorz Peszke has said before, during our conversations concerning the assumptions of this project, are proving to be true.
His considerations about distinctive aerodynamic traits of the construction, which he presented during the discussions at the design phase are really confirmed. Those weren’t just made up theories but the end result of many years of his RC modeling experience. Grzegorz has reached world top level in this field and has implemented it into larger devices.
It becomes clearly evident right from the first moments of the flight. The glider is extraordinary pleasant and easy to fly. With empty water ballast tanks, one has to restrain from pushing the rudder pedals too much, in order for the steering to be appropriate. The take-off is childish easy. The glider reacts on the controls’ inputs as soon as it starts moving forward.
It circles brilliantly. Using flaps deflection lesser than +2 or +3, it doesn’t stall at all. Whilst using more positive flaps deflection it’s still easy to control, even after the stall and I didn’t observe any abnormalities in its behaviour. In this configuration one can still continue the flight correctly. After letting the stick go, the glider fluently comes back to normal flight without any altitude loss. Fairy-tale. It resembles a school glider, forgives many mistakes and after these are made, it still listens to controls. Short wings and flaperons enable swiftly fast reactions. I can feel a huge difference in handling after jumping right out of overloaded with water 18-metre glider and one might’ve thought, that those modern gliders already are very easy to fly and can be used for pilots’ training.
I’m impressed by the propulsion system too. When turning aesthetic knob (one has to have a lot of imagination to control such power with such a small device) the magical force pushes you into the seat and the glider itself climbs as fast as 6 m/s rate. To be honest, I was amazed by that sensation and tried to throttle down, however that’s a mistake. With electric propulsion systems the best practise is to use 100% of the power available. The last time I remember climbing at this sort of angle during take-off was in Olsztyn having 70 km/h front wind. The climb profile was more less the same. The additional advantage of electric propulsion is the fact, that when there’s energy inside the batteries, you don’t have to wonder whether the motor would start. The unique pylon construction and propeller design, enables start-ups duration to be as short as few seconds and it functions reliably. During unfolding of the system, the influence on sink rate is marginal. One can retract the system completely right after turning the power knob down. No nightmare of setting up the propeller in foldable position. Just like that. How many times have you lost a lot of altitude fighting with the engine and the propeller on different types of motor gliders? How much emotions accompany such battles, when firstly one need to cool down the engine and the propeller becomes wind turbine, because the speed with water aboard is too great or it’s impossible to set it in foldable position allowing the retracting of the system into the fuselage? After that sort of shut off procedure of combustion engine and loosing few hundreds of metres, losing the thermal as well as manoeuvring to avoid hitting other ships, one might think it would be advisable to restart the engine again to gain back one’s altitude. How many forced out landings were there because of the engine start-up problem.
As far as performance goes, today I was able to test only the circling. The weather’s been poor and it rained a little. In turn hardly any rain influence on the glider was noticeable. It behaved correctly. It’s hard to assess if the glide angle is 1:40 or 1:50, however during circling I was amazed by the constant speed in wide range of stick and nose position in relation to horizon. One can slow down and down again, and the glider still flies normally. In other gliders it’s simple, on the edge of this angle the glider vibrates and the nose is descending, it’s not the case here. Incidental stall is practically impossible, because one has to firmly pull the stick to do that. The difference in stick position is 1/3 of the whole backward movement. The speed in wide range of nose position in relation to the horizon is almost constant and the vibrations during the stall very mild. It’s obvious that flying too slow flying is ineffective, therefore one might have to learn to find the optimal circling angle and pitch. I haven’t tested yet the properties whilst dynamic stalls.
I really can’t wait for the comparison with other gliders. It’s the only way for objective assessment of performance and abilities, however it’s going to happen really soon in Szatymaz.
Congratulations Grzegorz! Congratulations Jerzy! Congratulations to all the GP GLIDERS team! You’ve built gorgeous and wonderfully flying sailplane. Sebastian Kawa.