Foot pedals are connected via steel cables with the stabilizer and also with the upper rotor blade control. We have a patent to only use the upper rotor plane. If you give foot inputs, the upper blades change angle of attack and simultaneaously the aerodynamic drag also changes, while the drag of the lower blades stays as it is. This difference of drag leads to a yaw movement of the whole helicopter. With forward speed, the stabilizer is also helping to yaw, same as the rudder for airplanes.
After receiving the Type Certificate for the VA115 ultralight, RotorSchmiede will immediately start producing five pre-production helicopters, which will be offered at special conditions to and delivered to selected customers. Together with these customers, RotorSchmiede will conduct a field test campaign in the summer and autumn of 2018 in order to identify and eliminate the last potential teething troubles of the VA115 ultralight, paving the way for series production. The start of series production is scheduled for October 2018. RotorSchmiede intends to sell the VA115 ultralight at a price of 80 to 90 k€. Pre-orders will be available after receipt of the Type Certificate. We will inform separately. With the launch of the VA115 ultralight, the VA115 trainer platform will also be available, making it easier for beginners to get into helicopter flying. Please sign up on our website www.rotorschmiede.de to receive our newsletter.
I didn't see or hear a "split-the-needles" on the run-up prior to takeoff... Is there no "spragg clutch" in the design..? How would you enter a hovering auto or a full in-flight touchdown autorotation upon engine failure....? Thanks, Gordon...
The VA115 is indeed equipped with a "sprag clutch" or "free-wheel-clutch". It is needed to separate the autorotating rotor system from the engine and drive train in case of an engine malfunction or failure. The VA115 is fully capable of autorotation, which by the way is a requirement of the German Ultralight Helicopter Certification Specification ‘LTF-ULH’. Please sign up on our website www.rotorschmiede.de to receive our newsletter.
@@rotorlite Ein mehr Frage hat mal jemand eine Autorotation gemacht ? Oder war das noch nicht möglich ? Würde ich gern Mal sehen " Hover Auto " kann vorbei kommen wohne bei Deggendorf !
How do you perform dynamic balance of the rotors? I know how to perform it on a single rotor machine, but how do you separate the vibrations from each rotor?
Blades are balanced as you do on a single rotor helicopter. The lower and upper swashplates are connected with pushrods. Each blade can be adjusted, what means that those pushrods are not loaded very much because both rotors run very smooth after adjustment and therefore also not much vibration.
@@RS-fr1je I understand how the tracking could be achieved. However if there is slight in balance in one rotor say one blade is slightly heavier than the other or the center of mass is not exactly the same on both blades, an imbalance occurs with a resulting vibration. If the normal single rotor balancing is done, an accelerometer is used to measure the amount of vibration and there is an optical device employed to determine at what point or angle of the rotation does the accelerometer read its max. This is fine except which rotor is causing the vibration? Also this must be done in a hover to avoid the affect of the vibrations reflecting from the ground. On a single rotor ship that has the engine turning the same rpm as the the tail rotor, it is difficult to isolate vibrations coming from the engine vs the tail rotor. The dual rotors must exacerbate that problem?
@@stufields5125 We have the advantage to manufacture our own blades. They are made out of carbon fibre and are manufactured in a solid autoclave mold. So the outer geometry is always the same which leads to the fact, that there are no differences in aerodynamical behaviour between two rotor blades. As you already wrote, vibrations can occur due to differences in the whole blade mass or the centre of gravity. Now we have two directions of the centre of gravity: longitudinal relating to the blade length or lateral (blade width). Lateral tuning is done by measuring this c.o.g. and aligning the main fixation bolt exactly onto this line. But there's only a small range where this is acceptable. The c.o.g. should be at the same lateral position as the centre of aerodynamic forces in order not to flutter or to create unnecessary loads in the control system. The inner blade setup with additional weights is designed to reach that range and this is working quite good. If it's outside that range, the whole blade goes into the garbage. The longitudinal c.o.g. can be adjusted by small additional weights at the end of the blade, which also leads to a different total weight. The blade pairs of our helicopters are selected in pairs which fit best to each other at all design parameters in order to reduce vibration. So we don't manufacture 2 bades and say: "They will be attached to the next helicopter. If they don't fit to each other, we will tune them with additional weights." It's more that we manufacture 10 or 20 blades and select the best pairs before fine tuning is done.
@@RS-fr1je I found that to truly check dynamic balance on my Safari, I had to perform an measurement while hovering. This is done after a static balance check is performed and the blades aligned to eliminate any lead/lag and a tracking test and adjustment is done. My balance checks would involve hovering the ship with the accelerometer mounted close to the mast and pointed inward. An optical sensor was used to detect the angular position of the mast and rotor when the accelerometer reading peaked. This would tell me the angular position where the "Bad" wt was and I would use the plan "Add Opposite" to add wt to the rotor system at a point opposite the "Bad" wt. I would typically try to first add wt to the nearest blade tip and the repeat the test and find a reading of the chord wise balance. I was able to get total vibration less than 0.05 ips in three starts. This was of course after I determined gram wt vs ips. You sound like you are manufacturing a quality blade which should certainly reduce the dynamic vibration. That said how about the 2/rev vibration normally associated with a single rotor in forward flight? It has to be there but whether it gets to the pilot's butt is another question.
The VA115 is fully capable of autorotation, which by the way is a requirement of the German Ultralight Helicopter Certification Specification ‘LTF-ULH’. Training with the VA115 starts with the VA115 trainer (please see the dedicated video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-S2oOvowUwEs.html). The VA115 trainer offers future pilots realistic training possibilities, starting at the level of absolute-novices: • Ground based motion platform, enabling trainees a safe approach to learning to control a helicopter • No license or registration needed for operation of VA115 trainer while on ground • Platform couples with flightworthy VA115 to provide all degrees of freedom and safety limits at the same time • Offers realistic training and learning possibilities at lower cost than two-seat-trainers • All movements (vertical movement, horizontal movement, pitching/banking/yawing) can be limited separately, thereby adapting the difficulty and safety limits to the learning curve of the trainee • The trainee starts with learning how to control rotor / engine RPM at the beginning, and progresses via stationary hover to finally “free flight” - albeit still within the safe environment of the trainer. Having gained sufficient experience and skills of the basics of helicopter control with the VA115 trainer, the trainee will switch to a two-seat ultralight helicopter for advanced in-flight training with a flight instructor towards his first solo flight, before he returns to flying the VA115. Please sign up on our website www.rotorschmiede.de to receive our newsletter.
