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Have any of you guys or girls flown a Mini 500? I see the NTSB reports are full of incidents, but that can be attributed to pilot error, as well as mechanical failure. I'm a but leery about flying something that was built in someone's garage, but the EAA wouldn't be around if homebuilts were all bad.

 

Here is a nice (looking) example on that auction site.

 

Mini 500 on Ebay

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There's a lot of bad stuff on the net about the mini 500. I've read that the rotor inertia is so low that you can't get one to auto rotate. If that's true it would be suicide to go up in one.

 

As far as EAA not being around if all homebuilts were bad....Like the rest of GA, most EAA members are fixed-wingers. And there are a lot of safe airplane kits out there. Helicopters are a different story. Rotorway is probably the safest of the lot and I'm not adventurous enough to try even that. When they hit production maybe, but not as a kit.

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Have any of you guys or girls flown a Mini 500? I see the NTSB reports are full of incidents, but that can be attributed to pilot error, as well as mechanical failure. I'm a but leery about flying something that was built in someone's garage, but the EAA wouldn't be around if homebuilts were all bad.

 

Here is a nice (looking) example on that auction site.

 

Mini 500 on Ebay

 

 

Hey Fly,

 

Not to sound rude or anything, but have you tried to search for "Mini 500" on this forum? A number of posts come up and even at least one entire thread on the Mini 500.

 

For what it's worth,

 

-V5

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Hey Fly,

 

Not to sound rude or anything, but have you tried to search for "Mini 500" on this forum? A number of posts come up and even at least one entire thread on the Mini 500.

 

For what it's worth,

 

-V5

 

I did a search and I've been here long enough to have read those threads too. I was looking for someone with first hand experience building/flying one, but I should have know that most people here would know better <_>

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My instructor built one in the 90's and flew it.

 

He said it flew great.....but..and a very big BUT.....the engine was prone to seizure. It is very hard to get the 2 stroke jetted properly and the engine would just suddeny stop without warning.

 

After his third auto due to a seized engine, he decided he did not want to die and got rid of it.

 

A 2 stroke gets it's lubrication from the fuel/oil. It is a bad application for a helo because the engine always runs at 100%. (High rpm) So when you lower the collective, the engine is still running at full rpm but the fuel flow goes down and so does the engine lubrcation.

 

There was a very high time guy that died when his engine quit on climbout that I remember reading about....as well as many others...

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  • 11 years later...

have found a mini 500 that i really like. YES, i know they are known for alot of problems, but i wanted to ask you what i have seen. When they say in the ad if it has all updates, does that mean that all the problem items were corrected? what do you think about it if they are corrected?

 

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

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  • 1 month later...

have found a mini 500 that i really like. YES, i know they are known for alot of problems, but i wanted to ask ...

Alejandro,

 

I'm probably in the top 20 most Mini-500 hour pilots. I'll try to answer some of your questions.

"All Upgrades" means:

* Inserts inside the landing gear legs to stiffen them and prevent rollovers in hard landings

* Thicker frame tubes and bigger triangle gussets where the MRGB mounts

* Tapered roller bearings on the MRGB pinion shaft

* Chip detectors on main and T/R geaarboxes

* MRGB mounted on Barry neoprene mounts

* Engine clutch dynamically balanced

* Cast aluminum pitch horns instead of stamped steel

* Less "undersling" on rotor head

* Shorter pitch links

* Less coning angle on rotor head

* Less preload on blade feathering bearings

* Fore / Aft Cyclic damper installed

* Bottom Tie Plate on clutch mount brackets

* Trackable cogbelt idler pulley with spring tension tightening

* Mast Support frame to stop main frame flexing/cracking

* Main Blades now have bendable trim tabs to get better results during Track / Balance

* Many DU bushings in flight controls now have bronze oilite brass

* Anti-Balloon stall strips on upper surface of horizontal stab

*New tracking balancing polar charts

 

Even with all this, YOU must develop a method of getting oil to the upper mast bearing. In the stock configuration it runs dry and gets hot.

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Second answer Alejandro.

 

If you are a talented mechanic who is a meticulous tinkerer. You may be a candidate to fly a Mini safely.

 

I say "may" because you also must become a Rotax 582/Bing carburetor expert. You must learn/know/live the 2-stroke in a helicopter situation and all of its shortfalls.

 

You must keep accurate fuel and oil consumption records 100% of the time.

 

If you don't see yourself doing all these things, don't get a Mini-500.

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Don't see you at the other place nowadays Brian, how is the 500 going

Well,

The short answer is...it's down for maintenance.

 

The details... My super-dooper pinion bearing arrangement included increasing the center bolt diameter from 3/8 to 1/2 to create more locking force on the inner race stack. I was concerned they would spin and keep producing chip warnings. This required a MS20008 bolt so as to not interfere with the forward flex coupling. This required me to fabricate a custom conical washer.

 

My washer was a terrible design. The bolt shoulder squeezed on a thin portion of the washer when torqued and cause the washer to "cup." This loosened the inner race stack considerably. I didn't know this had happened.

 

I made one 5 minute maintenance test flight up I-75 and back. The chip light came on almost immediately. I changed the oil 4 times and hovered less than 5 minutes with a chip light each time.

I got mad and discouraged and put it away for a year and a half.

 

I recently pulled the pinion out of my flying MRGB and saw the exact source of my metal flakes. That stupid washer. The half hour of flight time had left some minor evidence of spinning races so I conservatively called the set unairworthy. I had to save up my lunch money to pay $1700 for another set of ARROW gears. I am currently building the new MRGB up with two Tapered Timken Rollers in the "indirect" configuration. A much thicker compression washer is already made and the issue will vanish this time. There will be no spinning races.

 

Other than my gearbox, nothing has shown any problems. I'm still fat so getting out of my yard with using max-performance departure technique is not possible. I have to be careful and go straight to the gas station or the airport.

 

The rotor is pretty smooth at 0.35 IPS at cruise but there's room for improvement. I am looking for a used DSS Personal Micro-Balancer for $500-$800. There's a Micro-Vib II for $2900 which is a steal but that's above my pain threshold. It's really more suited to the balancing professional and more bells n whistles than I need.

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I've been around these aircraft from the beginning. IMO, they are not as bad as the most ardent detractors claim or as good as the manufacturer led people to believe. The majority of people that completed their aircraft enjoyed flying them, but were experiencing premature component wear that eroded their confidence in the machine. After RHCI failed, hyperbole and personality conflicts took the place of technical discourse and a lot of kits and partially completed aircraft became hangar queens, were sold at fire sale prices or parted out. Anyone wanting to build one today better have a LOT of mechanical skill sets and be prepared to fabricate some of your own parts, especially if it is an earlier production ship! There are not a lot of people to help you anymore and it will likely cost you a lot more $$ than you think.

 

Bottom line, building a Mini-500 today is an uphill battle, with no factory support and the lack of constructive technical discourse between builders/owners.

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  • 11 months later...
On 4/7/2019 at 5:14 PM, Alejandro said:

have found a mini 500 that i really like. YES, i know they are known for alot of problems, but i wanted to ask you what i have seen. When they say in the ad if it has all updates, does that mean that all the problem items were corrected? what do you think about it if they are corrected?

 

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

 

Edited by Ben Banh
Hi Alejandro,
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On 5/18/2019 at 7:29 AM, Bryan Cobb said:

Alejandro,

 

I'm probably in the top 20 most Mini-500 hour pilots. I'll try to answer some of your questions.

"All Upgrades" means:

* Inserts inside the landing gear legs to stiffen them and prevent rollovers in hard landings

* Thicker frame tubes and bigger triangle gussets where the MRGB mounts

* Tapered roller bearings on the MRGB pinion shaft

* Chip detectors on main and T/R geaarboxes

* MRGB mounted on Barry neoprene mounts

* Engine clutch dynamically balanced

* Cast aluminum pitch horns instead of stamped steel

* Less "undersling" on rotor head

* Shorter pitch links

* Less coning angle on rotor head

* Less preload on blade feathering bearings

* Fore / Aft Cyclic damper installed

* Bottom Tie Plate on clutch mount brackets

* Trackable cogbelt idler pulley with spring tension tightening

* Mast Support frame to stop main frame flexing/cracking

* Main Blades now have bendable trim tabs to get better results during Track / Balance

* Many DU bushings in flight controls now have bronze oilite brass

* Anti-Balloon stall strips on upper surface of horizontal stab

*New tracking balancing polar charts

 

Even with all this, YOU must develop a method of getting oil to the upper mast bearing. In the stock configuration it runs dry and gets hot.

On 5/26/2019 at 11:58 AM, rotorr22 said:

I've been around these aircraft from the beginning. IMO, they are not as bad as the most ardent detractors claim or as good as the manufacturer led people to believe. The majority of people that completed their aircraft enjoyed flying them, but were experiencing premature component wear that eroded their confidence in the machine. After RHCI failed, hyperbole and personality conflicts took the place of technical discourse and a lot of kits and partially completed aircraft became hangar queens, were sold at fire sale prices or parted out. Anyone wanting to build one today better have a LOT of mechanical skill sets and be prepared to fabricate some of your own parts, especially if it is an earlier production ship! There are not a lot of people to help you anymore and it will likely cost you a lot more $$ than you think.

 

Bottom line, building a Mini-500 today is an uphill battle, with no factory support and the lack of constructive technical discourse between builders/owners.

 

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Brian why don,t you have a word with Steve Sennit at RPX they might help with balance for some feedback 

steve@rpxtech.com 

A friendly Co always returns calls & does what it says it will  we cannot fault them.

Say Peter & Tony suggested you had a word

We have had a very slow year due to other commitments & have not used the RPX enough to get a handle on it, hoping to ramp up next year

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  • 9 months later...

My grandfather purchased a mini 500 in 1999 and was building in his living room. He passed away last year and we had to remove an outside wall to get it out of the house I dont think he ever intended to fly it and it has never been started so I would call in brand new.

We just got it out of the house and this thing is in mint condition with I'm guessing 75% complete with the pilot compartment being what's left. All uninstalled parts are still in original packaging and this unit has zero hours I checked the assembly manual and everything is here to finish it. If anybody wants it I will take $8500 I'm in oregon and will deliver anywhere on the west coast of the United states for extra small fee. Contact me. Towguyoregon@hotmail.com

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