Bulletin Service Level: Informative Date: 18th April 2010
WARNING!
As seen during the AERO 2010 in Friedrischhaffen Germany, a private Xenon R was modified and displayed on the SILENT Hektik booth, without any prior authorization from us.
The 125 hp engine he mention is the one mounted by Tom Schoenmann is a originally Weber engine, “prepared” by SILENT HEKTIK company. It is totally out of question to let anyone modifying without our prior consent the Xenon, due to the very high complexity of technical interaction between components, due to the lack of knowledge, and the total non-respect of the original product. The Tom model was displayed in AERO on the SILENT HEKTIK booth, see as per the taken photos. The tail number seems to be the original one, therefore this machine is illegal.
Plus, we did not proceed to make such installation of this engine, simply because it is heavier than the “advertising”, more heavy than our RST, much less powerful, the torque is much very low compare to our RST. Speaking with the original engine manufacturer, we came mutually to the conclusion that this engine was NOT suitable for Xenon use. The propeller trust is much to low in dynamic. And if the engine is pushed too far in turbo boost, its original construction does not support it, crank-shaft breaks. Lots of vibrations are noticeable compare to the Rotax engine. This engine was not developped initially for aircraft use.
If that engine was delivering what it promises on brochures, it would already be installed by us. But it is not the case…unfortunately.
Looking at the engine installation, it is not properly done anyway, and will involve safety issues.
Looking at the pre-rotation system, hydraulique, it was already done years ago by our company, and abandoned also for safety and complexity reasons.
Looking at the inside cabin we noticed a deep modification of the seat (right one), it cannot therefore give the original anti crash protection as it was specially designed for.
Looking at the control system, some controls have been removed, due to the new engine installation, and the electrical circuit fully modified. No comments…
We therefore strongly give opposition to all these modifications, the global safety is deeply involved. We cannot also recommend the company SILENT HEKTIK and its owner Toni Kurpas, doing behind the back of a manufacturer such things. This is totally heretic and non professional attitude.
About the silencers, Norbert Braun (our actual distributor) knows that we have made a strong and careful research by testing 6 different models, the original Rotax one happened to be one of the worst with only -3dBa, even though it passed the original certification. One silencer was bought from Scheibe Aircrafts, while certified, it did not give any better results than the original Rotax version and with a poor construction quality. Plus 4 other CELIER Aviation original designs. The best one appeared to give -6 dBa. We are now in the preparation of producing that best model for the Rotax 912S, and we will propose it for a new noise test. Our latest technology will be used to propose also a correct silencer for our RST Xenon as well, a proven design and engine solution, as a special version is in preparation for the German market.
About the propellers. We saw that the IVOPROP electric variable pitch, large blades model, that Tom tested private, against our prior advice, as we know very well that variable pitch prop ; it is a dangerous model propeller for the ROTAX engine on the large and heavy blade used version, its inertia momentum is too high, create known fatigue to the crankshaft and crankcase, causing rupture. It was long time ago tested by us, with negative results in: trust, noise, vibrations (blade cavitations), it is not enough reason that it is a cheap VP propeller to adopt it without any consultation or negtive advice from experienced manufacturer as we are. Tom Schoenmann Xenon Rotax IVO was tested in his place, and was found noisy, and with a true lack of performance in speed and climb rate. The big IVO prop can only lower the RPM, stressing the gear box and crankshaft. More on that, this propeller is heavy, and with time finds its VP system in-blade rods getting loosed, thus losing pitch precision, causing vibrations.
We are currently collaborating with DUC propellers, around a VP FC model, only for our RST model. For repeated information, a VP prop, on gyroplanes with speed range of 0 to 180 km/h is a non sense around the ROTAX 912 S. The DUC FC has a very special feature, to automatically pitch up with speed, by means of known and calculted torsional effect from the carbon. Tested and proven effective. Therefore, it acts like a VP model, without the weight, mass inertia, the complexity, the cost, the requested higher skills to operate it safely.
p<>. About the seen and PROPOSED back engine cover. It is another non sense, made in the total lack of aerodynamic knowledge of the Xenon very special aerodynamics. This amateur approach only engage its owner, and should not be publicly presented as it was seen in AERO. This modification, will change the behavior of the Xenon and affecting its security.
We therefore, denunciate all these modifications, and we do not recommend anyone to attempt to do the same.
We shall not be hold responsible for any flying attempt of this machine, and possible dangerous issues.
Another proposal was seen on the German gyro forum, it concerns the landing gear system, proposed in carbon version. This was studied about a year ago by our R&D team. It appeared to be totally non-adapted for the gyroplane for the simple reason that a composite landing gear system has too much spring effect, this is HIGHLY DANGEROUS on a gyroplane. Just as per you would definitely make a bow in carbon to have a super spring effect, it would simply not work from FORTAL aluminum. A bouncing impact made on landing induces immediately a potential blade flapping with all fatal consequences corresponding. We therefore, abandoned that “elegant” but dangerous solution, and we retained our aircraft aluminum gears.
This is in fact one of the secret of the Xenon to be also so forgiving on take-off and landings, and it also explain the high rate of many accidents on concurrent machines. We will never install such composite / carbon landing gear legs.
We at CELIER Aviation, have the grand advantage to collaborate with Governmental institutes like WARSAW POLYTECHNIC, AVIATION POLYTECHNIC, for any stress, force, simulation, analysis we need.
We then consider criminal the proposal on internet, gyro forum, airshows of such silly modifications. This is unfortunate that non-true professionals try take opportunity of our success.
DAEC and authorities are informed of this situation, and shall take the legal and proper actions.
For the future, at the attention of Norbert Braun, customers, suppliers ; we at CELIER Aviation, have deep knowledge in all necessary areas, our team of 26 people is highly professional and skilled. We have the culture of listening to our customers for the ideas, suggestions, proposals. We systematically make meetings afterward to debate of the pros and cons of it, it is very often tried, tested, analyzed and finally accepted or not. But when it is not accepted, it is certainly due to true technical facts, that the public and amateurs may not perceive. It is our permanent intention to make the best evolution of our product.
We hope that this letter will alert sufficiently all of you, to keep you flying safe on the original Xenon product.