![]() |
If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
![]()
Dear Sir,
Thank you for your kind post, and taking the time to do so. Shiver wrote: Well Dennis I've certainly read my share of Mini 500 stories over the years. As a lurker I can't make any comments because I like many have no direct knowledge of the facts or issues regarding the history of RCI. BUT ----- I will give you full credit for coming into this newsgroup numerous time and presenting your point of view good bad or indifferent in a rationale and logical manner, devoid of rants and cursing. Thank you, I try. Hindsight being 20/20 vision I'm sure that if you had to do it over again you would have done many things different. As with anything... I feel that my biggest mistake was assuming anyone could build, operate and maintain a kit helicopter. I was wrong there, very few can do so, even with the certified helicopters. Our assembly manual was excellent. Very nice exploded drawings, pictures and step by step instructions. The common mistake that about 90% of the Mini-500 builders made was the same; they didn't read the instructions and only followed the drawings and pictures. Believe it or not, but true. This lead to many common mistakes, from not heating the parts before installation to missing parts. I can't tell you how many times an owner would come to the factory with his Mini-500 for the free inspection we offered, only to hold out his hand and ask why he had extra parts, and always after he had 40 hours of flight time on his Mini-500. They most all came to the factory after something was going wrong, and it was always a simple overlooked procedure or something assembled wrong, and always after they flew it until it broke. Some aircraft were so far out of balance that they shock themselves apart in only 40 hours, and only because the builder didn't bother to balance it, or did it wrong and ignored the fact that he did it wrong. On the other hand, we had some design problems that had to be addressed. Since we were shipping 5 to 6 complete kits a week, and since the average time for the builder to complete the kit and fly 40 hours was about 4 months, we could have shipped 80 or more aircraft by the time we received word of a problem a builder may be encountering. So by that time, it's a major deal, not like Uglysport or Angle helicopters that have only sent out a handful of aircraft over a long time. So this also made the situation seem worse because it involved much more people. What would I have done differently using hindsight? I would have tripled the price of the Mini-500 and sold much less of them to people that can actually afford to own a helicopter, and built it under our complete supervision. Then I could have had a much smaller factory with less overhead, and fewer customers that would have paid more, and maintenance or improvement costs would have not mattered to them so much, because they could afford it, like in the commercial aircraft field. It would have just been too bad for someone that wanted a helicopter but couldn't afford one, which the Mini-500 did fit the bill. Being a curious person I'd like two ask a few questions. I would be honored. Since a lot of these machines suffered from engine failure regardles of how they were supposed to be set up or run, what did the engine manufacture say, or what was their position on these failure. The engine manufacturer always read our reports, but they never pretended to understand the needs of helicopters. They just supplied the engines. They were concerned but satisfied with the reasons of the failures, and supported our continuing effort to make the builder follow instructions or find ways to make the engine more resilient to misuse. As we learned and experimented, this was done with the mandatory addition of the Power Enhancement Package system, "PEP" for short. That was a tuned exhaust system that moved the power band up to operational RPM's where a helicopter operated. That not only took care of the low rotor RPM's that our low time pilots were having by increasing the torque, but gave the helicopter more overall performance, and reduced the exhaust back pressure which made it much less sensitive to EGT change, and took away the need to rejet for density altitude changes. And yet, even with all it offered, not even half of the Mini-500 owners installed the PEP in their aircraft, and they continued having failures due to the reasons above, while the PEP Mini-500's are still performing well. You can led a horse ot water, but you can't make him drink. And why didn't you change engines to either a different manufacturer or a higher horsepower. I'm not trying to put you on the spot because I know there was a lot of controversy regarding the engines being used and how they were being run at high rpm. Back in 1990, when I first started the Mini-500 project, there was only one engine manufacturer that could provide 5 engines "new-in-the-box a week", that had a performance history, and had service all around the world. That was Rotax. The Mini-500 was designed around the 582 Rotax engine. There was nothing else available. That is still as true today as 15 years ago. The 582 Rotax is a good choice for the Mini-500. It has the power necessary to do the job, at the price people will pay. The engine was only ran at 6600 RPM's, which is still a 100% duty cycle for the engine at 70% power reduction. Remember, the same engine in the snowmobile industry will produce 110 hp at 8500 rpm's. Rotax simply derated the engine for aircraft by lowering the RPM's. If you look at the power charts of the snowmobile, the output HP at 6500 rpm is 64HP. No Rotax in a Mini-500 has ever failed due to overexertion, if operated properly. Only to improper installation or improper (or lack of) maintenance. It is the finest light-aircraft engine ever made. Also in the light-aircraft industry, 98% of all Rotax failures are due to poor installation or inadequate maintenance. If you want a bulletproof idiot-proof engine, buy an O-200. The Rotax was, and is still the only choice of engine for the Mini-500 size helicopter, for the price people want to afford. Some people have tried to replace the engine with something else, and all have failed. Even the Solar APU engines will never work as intended. They burn more fuel than you can carry, have no explosion proof protection, and the low duty cycle makes them burn out quickly. They are not turbine engines, they are merely self-propelled turbochargers meant to power generators and pumps. To this day no one has been successful, except me with the Rotax engine. And if you don't mind..... what are you personally doing these days. I have a Research and Development business where I design and build rotorcraft of various types for customers around the world. I'm doing what I want, and that's not to have to deal with people any longer. I have found that large businesses and governments have much more money to spend. If you would like, I would be happy to send you some pictures of my previous accomplishment, the Star-Lite UAV helicopter, and the new helicopter I'm designing and building for another customer. Again, thank you for asking, and I hope I was able to answer your questions effectively. Most sincerely, Dennis Fetters |
#2
|
|||
|
|||
![]()
So, let's see where we're at...
The sappy letter (only for Jim, wink-wink) was indeed yours. Next, you cry out "You have absolutely no respect for anyone" "the big difference between you and me is respect for others." Shiver commends your "rationale and logical manner, devoid of rants and cursing." And your impeccably gracious reply contains: "not like Uglysport or Angle helicopters" Uncalled for, childish name calling against two other kit heli manufacturers. See, folks? |
#3
|
|||
|
|||
![]() |
#4
|
|||
|
|||
![]()
As with anything...
I feel that my biggest mistake was assuming anyone could build, operate and maintain a kit helicopter. I was wrong there, very few can do so, even with the certified helicopters. Our assembly manual was excellent. Very nice exploded drawings, pictures and step by step instructions. The common mistake that about 90% of the Mini-500 builders made was the same; they didn't read the instructions and only followed the drawings and pictures. Believe it or not, but true. This lead to many common mistakes, from not heating the parts before installation to missing parts. I can't tell you how many times an owner would come to the factory with his Mini-500 for the free inspection we offered, only to hold out his hand and ask why he had extra parts, and always after he had 40 hours of flight time on his Mini-500. They most all came to the factory after something was going wrong, and it was always a simple overlooked procedure or something assembled wrong, and always after they flew it until it broke. Some aircraft were so far out of balance that they shock themselves apart in only 40 hours, and only because the builder didn't bother to balance it, or did it wrong and ignored the fact that he did it wrong. == This is probably true of all kit a/c, it's just more critical in helicopters. I follow the Rotorway forums and they have the same problem with their kits. What would I have done differently using hindsight? I would have tripled the price of the Mini-500 and sold much less of them to people that can actually afford to own a helicopter, and built it under our complete supervision. Then I could have had a much smaller factory with less overhead, and fewer customers that would have paid more, and maintenance or improvement costs would have not mattered to them so much, because they could afford it, like in the commercial aircraft field. It would have just been too bad for someone that wanted a helicopter but couldn't afford one, which the Mini-500 did fit the bill. == Price seems to be directly related to helicopter accidents. When the Robinson R22 first came out untrained pilots could suddenly afford a helicpter. R22s were raining from the sky before Robinson started mandating proper training. Back in 1990, when I first started the Mini-500 project, there was only one engine manufacturer that could provide 5 engines "new-in-the-box a week", that had a performance history, and had service all around the world. That was Rotax. The Mini-500 was designed around the 582 Rotax engine. There was nothing else available. That is still as true today as 15 years ago. The 582 Rotax is a good choice for the Mini-500. It has the power necessary to do the job, at the price people will pay. The engine was only ran at 6600 RPM's, which is still a 100% duty cycle for the engine at 70% power reduction. Remember, the same engine in the snowmobile industry will produce 110 hp at 8500 rpm's. Rotax simply derated the engine for aircraft by lowering the RPM's. If you look at the power charts of the snowmobile, the output HP at 6500 rpm is 64HP. No Rotax in a Mini-500 has ever failed due to overexertion, if operated properly. Only to improper installation or improper (or lack of) maintenance. It is the finest light-aircraft engine ever made. Also in the light-aircraft industry, 98% of all Rotax failures are due to poor installation or inadequate maintenance. If you want a bulletproof idiot-proof engine, buy an O-200. The Rotax was, and is still the only choice of engine for the Mini-500 size helicopter, for the price people want to afford. Some people have tried to replace the engine with something else, and all have failed. Even the Solar APU engines will never work as intended. They burn more fuel than you can carry, have no explosion proof protection, and the low duty cycle makes them burn out quickly. They are not turbine engines, they are merely self-propelled turbochargers meant to power generators and pumps. To this day no one has been successful, except me with the Rotax engine. == Rotax is the engine of choice for most Ultralights and it performs well and reliably as long as it's installed and maintained properly. Would I personally fly with one in a light helicopter? Probably not, but that's just me. |
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
Selling on Ebay | Jay Honeck | Piloting | 34 | May 28th 04 06:29 PM |
Selling my Garmin Pilot III Aviation GPS and MORE on ebay | Cecil E. Chapman | Products | 0 | January 29th 04 12:44 AM |
Airplane Parts on Ebay Vac Reg Valves, Fuel Floats, O-200 Spider, Fuel Injection Valve | Bill Berle | Home Built | 0 | January 26th 04 07:48 AM |
Airplane Parts on Ebay Vac Reg Valves, Fuel Floats, O-200 Spider, Fuel Injection Valve | Bill Berle | Aviation Marketplace | 0 | January 26th 04 07:48 AM |
Airplane Parts on Ebay Vac Reg Valves, Fuel Floats, O-200 Spider, Fuel Injection Valve | Bill Berle | Owning | 0 | January 26th 04 07:48 AM |