Mini 500 Questions
Posted 27 June 2010 - 00:13
Thankks in advance,
Posted 27 June 2010 - 12:59
Posted 27 June 2010 - 14:12
That's one of the main reasons I posted this topic. If i do decide to buy this 500, id most definately do it with intentions of swapping out the motor! Turbine being first choice! Although a used lycoming out of a 22 that was cracked up or something. I do not trust the rotax. I've owned plenty of jetskis that seized at full throttle, and i consider myself a well capable mechanic! Just don't trust that motor with my life at 900+ feet and 100kts!
I didn't have time to read all of them, but I would guess that the majority of the crashed ships had the Rotax engine. I wonder how the 500's with the turbine engines are holding up.
- TomPPL likes this
Posted 29 June 2010 - 13:47
The accident Mini-500 used a Rotax 582 UL DCDI engine. In the beginning of the operator'smanual, it stated: "Danger! This engine, by its design, is subject to sudden stoppage! Enginestoppage can result in crash landings. Such crash landings can lead to serious bodily injury or death.Never fly the aircraft equipped with this engine at locations, airspeeds, altitudes, or other circumstances from which a successful no-power landing cannot be made, after sudden enginestoppage."
The operator's manual also stated: "Warning! This is not a certificated engine. It has not received any safety or durability testing, and conforms to no aircraft standards. It is for use in experimental, uncertificated aircraft and vehicles only in which an engine failure will not compromise safety. User assumes all risk of use, and acknowledges by his use that he knows this engine is subject to sudden stoppage."
I don't know about you guys, but that scares me. I'd never want to get into any vehicle with an engine that is "subject to sudden stoppage".
Edited by Tarantula, 29 June 2010 - 13:47.
Posted 30 June 2010 - 16:03
Now regarding the Mini 500, my father (licensed A&P and professional helicopter mechanic) built and flew one, until the final-drive belt blew while he was going through transition. Due to him being in that nasty part of flight we helicopter pilots call the deadmans curve, he had little time and altitude to do much. He was able to get it on the ground, but when it did, the blades struck the tailboom and rolled the aircraft on its side. He was able to remove his radio and gps before a fire totaled the aircraft. He walked away with no injury's, minus a broken heart from his machine burning to the ground!
Mini 500's have their problems just like any other aircraft that is in its infancy, of which it never left. I have looked at purchasing one myself, but with words of advice from my father, I have passed. He has no qualms about the Mini, he just gave me some advice about purchasing an aircraft that has no factory support! You buy it, don't expect to be able to call the factory on any technical or parts support. That was the deal breaker for me!
Now with that said, if you have a full machine shop, the talent, the know how to make your own aircraft parts, and the drive to be your own R&D department for the machine, I'd say go for it! Many of the Mini 500 owners and pilots will tell you it was an amazing flying machine and that it performed comparable to much larger and expensive general aviation helicopters. Just be forewarned, there will be no support, besides maybe a dedicated Mini 500 community somewhere. Either way you choose, I wish you the best of luck and the most enjoyment!
Posted 07 April 2019 - 19:17
Also the majority of the problems, stemmed from the engine vibrations and the others, just poor design. What if i got a turbine and swapped the old motor out with it? I just like the looks of the mini 500, but if i coulbn't make it safe, i sure wouldn't stake my like on one and just go with another type. thanks
Posted 17 May 2019 - 19:35
OK folks... I have been a Mini-500 enthusiast since the mid 1990's. I wound up owning and flying one in 1997 & 98 and had put a full 100 hours on it when I sold it because the company was hemorrhaging.
I bought a new, unbuilt kit in 2013 and got the airworthiness done in 2016. I have been flying it off and on since then. It only has 28 hours at this moment. I gained a lot of weight and got up to 285, which is definitely too fat for the Mini so it sat. Now I'm down to 255. I'm almost down enough to fly again.
I am very confident in the Rotax 582. I have been an ultralight guy too since the late 80's I have over 500 hours in the air with a 582 and a 503. I have never once had a single issue of any kind.
Now I HAVE almost been killed in my new Mini-500 twice. Both would have been MY FAULT. First, I had a bad habit of flying with strong cyclic friction applied so I could take my hands off the controls for other tasks. I was not aware this was flexing and fatiguing ONE VERY CRITICAL ROD END inside the console. I landed one day and as the rotor was spooling down, the rod end failed and the cyclic stick fell into the console and hit bottom! I grabbed it and held it still until the rotor stopped. After repairing it much stronger, I quit the bad habit of flying with friction applied. I only use friction on the ground.
The other time, I landed at the airport to get 10 gallons of gas. I got distracted and THOUGHT I had asked the truck driver to add 10. I didn't check and took off. I flew home (10 miles) and landed safely, unknowingly on 1.5 gallons in the tank. During postflight I noticed that the fuel level was only 1/8" above the pickup line! I almost passed out. If I had been airborne 30 more seconds, I would have ran out. I was very stupid and learned from it. I installed a Bee-Lite weight-based fuel gauge with several audible and visual warning features.
In a helicopter, the pilot better have a very deep understanding of the strange problems with flying a helicopter with a 2-stroke before doing it. One reason I have been successful is because I was an avid RC helicopter guy in the early days. I learned the hard lessons about a 2-stroke in a heli.
Here is the problem. Helicopters operate under the "constant RPM / varying power" umbrella. Well...if the oil supply comes from the mixed fuel and oil, and if the piston travels 12,000 times the stroke length of the cylinder, constantly every minute (at 6000 RPM), and if the pilot decreases the power to slow down or descend by significantly decreasing the throttle...BAM! Oil starvation causes seizure.
The solution is twofold and simple. You must understand this phenomena and know how to prevent it by deliberately installing VERY RICH mid-range jets. You must have very accurate dual EGT readout and understand what you are seeing and what to watch for. I even have a tiny lever on the collective near the throttle that activates the Bing enricheners on the carburetors. I have never needed it but If my EGT's ever begin going to high, I can use the lever in flight to richen up the engine and keep it from seizing.
Second, if you have ever ridden a 2-stroke dirt bike, you know that the engine only develops good power when it is screaming. It is commonly referred to as the "power-band." Outside that narrow RPM range, it has almost no power.
Now imaging you are hovering a Mini-500 in the power-band and just momentarily you don't pay attention and the RPM begins to sag. It gets out of he power-band pretty quickly and you will never recover your RPM. You are GOING TO settle until you hit something. I did this early in my Mini-500 days and got lucky. I was in a good spot and just plopped down without rolling it over. I got out, scared to death and looked deeply into what had happened. When I understood...I went into the air again and never allowed it to happen again.
When I was at Ft. Rucker in flight school, I remember my Primary instructor telling me "in all low RPM events...recover Thy RPM at all cost!!" "Do NOT add pitch ever, if your RPM is low,"
Well...For the Mini-500 to be flown safely, you have to live by my instructor's words, with a slight twist. Change it to "KEEP THY ROTOR RPM UP AT ALL COST. NEVER DO ANYTHING THAT MAKES YOUR RPM DROOP."
Almost all of the bad publicity the Mini-500 got on the internet was because pilots had no idea that a different mindset is required with a 2-stroke. They were totally ignorant of the drooping RPM scenario and were not as lucky as me. The result was many many hard landings and rollovers. Add to that the engine failures that happened because the pilot didn't have a clue how to jet the carburetors correctly. The engines were seizing left and right because the pilots were Bing Carburetor ignorant and partially because Fetters furnished Chinese EGT probes with the kits that were awful for giving the pilot accurate numbers of how hot their engine was running.
The final nail in the coffin for the Mini back then, was when these accidents started happening, it made owners mad that they had balled-up the beautiful little helicopters. They started publicly attacking Fetters and blaming it on him. He had put his heart & soul in this thing and that made him mad at his customers. The public internet fight was nasty and the little helicopter got a reputation as a piece of junk and a death trap. It never really got a real chance to have the bugs worked out and benefit from an educated, well-trained group of pilots.
That's the Reader's Digest version of the bad rap the little helicopter got. With my 130 hours or so in two of them, I have to say it's a good little flying machine. Now it is a go-kart. It's not a real passenger car. It does not FEEL or FLY like a Jet Ranger. It feels like a really really nice go-kart. It maneuvers like a sports car. It's quick on the controls. Just because it CAN do that, doesn't mean you should fly it like a musterin' pilot in Australia. I fly like I have passengers who get sick easily. It looks totally badass in the air, especially with that bold MD500 Notar color scheme I put on it.
I love it. I'm sad that people aren't learning how to fly them reliably and enjoying them. It costs me about $20 per hour to fly. I have about $15,000 in my new one and really enjoy it.
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