Mini 500 forum ??

Hi there guys hope you are all doing well. Im very happy to read about the guys involved with the Mini 500. Mr Fetters, it is really nice to be able to chat to see that you are involved in this thread about your Mini 500!! I have always wanted a Mini 500 as a kid and now i finally found one but they change the engine to a Hirth F30E....But it only did 30hours
looks nice at least. however, it need the mast support system AD#031599 and AD#092299 transmission pinion bearing retainer.

One issue I would have if buying a 2nd hand helicopter, no matter of brand, ask my self: "is it assemblied according to manual, are the AN nuts&bolts used only once, has correct torque been applied?"

i remember that rhci offered to go through the M5's if brought to the factory, and every one they checked differ from the manual (correct me if i'm wrong), it was mentioned in the paper "reaching the customers".

one guy in sweden bought a exec 90, it had logged something like 20 hours. he said to me " it was impossible it could have been flying a single minute since the transmission was incorrect assemblied". one should also remember, it was origionaly assemblied by a doctor, propably with limited mechanical skill. okay, not everyone is like that, but it should been considered.

also remember, you should invest in a microbalancer too.

i can see that it has EIS, great! better monitoring of the engine, even though it has a hirth instead of the rotax. some owner reported that egt probes failed (don't know how many), started show incorrect values. now i'm speculating... maybe it could be a indirect cause of some of the seizures on the rotax.

the owner of kit #15 280+ hours wrote that after 60 hours westberg egt probes started fail. he replaced them with 712-4D2KEHT.
before that, he allready had 2 sets failing
 
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This is a question, maybe to Mr Fetters, and of course to others. Is there some possibility to re-publish rhci information online?

There is soo much important information to share between existing M5 owners. For example Pilot to Pilot information by Brian Thomas, service information, the paper "reaching the customers", maybe builders forum, even the assembly manual, AD's and so on.

A homepage, not a forum, since it should contain proper information. forum seem sometime get out of control.

I really enjoy reading this old information, very informative and well written, professional.
 
looks nice at least. however, it need the mast support system AD#031599 and AD#092299 transmission pinion bearing retainer.

One issue I would have if buying a 2nd hand helicopter, no matter of brand, ask my self: "is it assemblied according to manual, are the AN nuts&bolts used only once, has correct torque been applied?"

i remember that rhci offered to go through the M5's if brought to the factory, and every one they checked differ from the manual (correct me if i'm wrong), it was mentioned in the paper "reaching the customers".

one guy in sweden bought a exec 90, it had logged something like 20 hours. he said to me " it was impossible it could have been flying a single minute since the transmission was incorrect assemblied". one should also remember, it was origionaly assemblied by a doctor, propably with limited mechanical skill. okay, not everyone is like that, but it should been considered.

also remember, you should invest in a microbalancer too.

i can see that it has EIS, great! better monitoring of the engine, even though it has a hirth instead of the rotax. some owner reported that egt probes failed (don't know how many), started show incorrect values. now i'm speculating... maybe it could be a indirect cause of some of the seizures on the rotax.

the owner of kit #15 280+ hours wrote that after 60 hours westberg egt probes started fail. he replaced them with 712-4D2KEHT.
before that, he allready had 2 sets failing
Look..that is why I joined the Forum and meet you guys so I can get all the help I can get. I'm going to completely rebuild the Mini 500. Dye pen test all the welds on the frame just as a start. I want to rebuild and rebalance everything. I'm trying to get the history of the Mini to see where it was built or where it came from. I'm going to post vids and pics as we go along. My family owns a big engineering company with CNC machines so building or machine things is not a problem.
 
Hi there guys hope you are all doing well. Im very happy to read about the guys involved with the Mini 500. Mr Fetters, it is really nice to be able to chat to see that you are involved in this thread about your Mini 500!! I have always wanted a Mini 500 as a kid and now i finally found one but they change the engine to a Hirth F30E....But it only did 30hours

A fact is that 98% of all engine failures in all types of aircraft are due to improper or badly designed engine installations. Yet, people tend to blame the engine alone when it takes a crap.

That being said, the Hirth F30 4 cylinder engines were notorious for failing. How is this engine being cooled? Open-air? No fan-forced cooling? Not enough pictures to tell for sure here, but I would highly suspect the safe operation from what I see here.
 
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The way I understand it the Mini 500 performed as advertised .... the issues they did have were hot-seize of the Rotax engine if mixtures were not set properly .... if owners followed factory jetting advice , and used the PEP exhaust system and kept a close eye on EGT those issues could be solved ...... with the Rotax running at near maximum output you had to get everything "just right"
 
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The way I understand it the Mini 500 performed as advertised .... the issues they did have were hot-seize of the Rotax engine if mixtures were not set properly .... if owners followed factory jetting advice , and used the PEP exhaust system and kept a close eye on EGT those issues could be solved ...... with the Rotax running at near maximum output you had to get everything "just right"

The only way to hot-seize the engine was to not allow for proper warmup time before takeoff, as the flight manual explained. However, not jetting the engine correctly, like with any two-stroke, would seize the engine due to lack of lubrication, which made it run hot and causing failure.

As time went on, we discovered there were better ways to jet the engine that were more suitable for helicopter operations. The PEP system made that jetting less critical while adding performance as well.

In hover, the Rotax with the PEP system was running at around 70% power levels, well within acceptance. Jetting was never an issue again after PEP installation.
 
Look..that is why I joined the Forum and meet you guys so I can get all the help I can get. I'm going to completely rebuild the Mini 500. Dye pen test all the welds on the frame just as a start. I want to rebuild and rebalance everything. I'm trying to get the history of the Mini to see where it was built or where it came from. I'm going to post vids and pics as we go along. My family owns a big engineering company with CNC machines so building or machine things is not a problem.
The only way to hot-seize the engine was to not allow for proper warmup time before takeoff, as the flight manual explained. However, not jetting the engine correctly, like with any two-stroke, would seize the engine due to lack of lubrication, which made it run hot and causing failure.

As time went on, we discovered there were better ways to jet the engine that were more suitable for helicopter operations. The PEP system made that jetting less critical while adding performance as well.

In hover, the Rotax with the PEP system was running at around 70% power levels, well within acceptance. Jetting was never an issue again after PEP installation.
shit! mr fetters - you know what you're talking about! thanks for beeing out there.
 
Hi there guys hope you are all doing well. Im very happy to read about the guys involved with the Mini 500. Mr Fetters, it is really nice to be able to chat to see that you are involved in this thread about your Mini 500!! I have always wanted a Mini 500 as a kid and now i finally found one but they change the engine to a Hirth F30E....But it only did 30hours
Howdy M, great that you finally have a " mini 500 " ...enjoy & have fun
 
Look..that is why I joined the Forum and meet you guys so I can get all the help I can get. I'm going to completely rebuild the Mini 500. Dye pen test all the welds on the frame just as a start. I want to rebuild and rebalance everything. I'm trying to get the history of the Mini to see where it was built or where it came from. I'm going to post vids and pics as we go along. My family owns a big engineering company with CNC machines so building or machine things is not a problem.
i think you should have the available information published by rhci before getting started. they gave really great advices, for example: assemble of the windscreen, if it's not done correct, it will induce vibrations. so this is really important things to know before starting to put it together. many builders contributed too with valuable information, such as "think about this before you do an assembly".

from "builders tips":
don't use MA300 as sealant between metal filler neck and plastic fuel tank.

another example:
how can you determin if the clutch has been dynamically balanced?
1-if it was shipped on or after june 1997.
2 - if the clutch drum nickel plating has been removed and shows machine marks.

so it's important to have this extra information.

other advices are that a Robinson helicopter have a adjustment and break in period of 5-20 hours, done by a professional company. M5 is no different from certified helicopters, it also need necessary working hours.

attach a pic of the current status of my project. only cabin is put together with pliers.
 

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A fact is that 98% of all engine failures in all types of aircraft are due to improper or badly designed engine installations. Yet, people tend to blame the engine alone when it takes a crap.

That being said, the Hirth F30 4 cylinder engines were notorious for failing. How is this engine being cooled? Open-air? No fan-forced cooling? Not enough pictures to tell for sure here, but I would highly suspect the safe operation from what I see here.
Well at the moment there is no cooling the engine is open. But all the cooling fans and all the cowlings are available. I'm so happy I found this forum and to hear all you experienced gentlemen talk about the Mini 500. So I would like to hear your opinion on going electric on the mini 500? I haven't gone to fetch it yet but I flew to Durban here in South Africa this past weekend to go and have a look at it. And it needs a lot of TLC but it not wrecked.The main rotor is leaking oil. It's standing next to the coast so there is a lot of rust spots. It flew 4 years ago but with carbs on the engine. At the moment there is an EFI setup on there that needs some work. There is a complete F30 that comes with the Mini so. I'm in two minds with the engines. And where would a find a new cowl for the rear? He gave me the logbook as well so it looks like this was built in 98 or 97.
 

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i think you should have the available information published by rhci before getting started. they gave really great advices, for example: assemble of the windscreen, if it's not done correct, it will induce vibrations. so this is really important things to know before starting to put it together. many builders contributed too with valuable information, such as "think about this before you do an assembly".

from "builders tips":
don't use MA300 as sealant between metal filler neck and plastic fuel tank.

another example:
how can you determin if the clutch has been dynamically balanced?
1-if it was shipped on or after june 1997.
2 - if the clutch drum nickel plating has been removed and shows machine marks.

so it's important to have this extra information.

other advices are that a Robinson helicopter have a adjustment and break in period of 5-20 hours, done by a professional company. M5 is no different from certified helicopters, it also need necessary working hours.

attach a pic of the current status of my project. only cabin is put together with pliers.
Hi Honken. I would love to go through all the info before I get started. I want to replace all the rose joints the are all sticky. So I need info on what to use there. There is lots of work for me and lots of photos still to come!
 
Hi Honken. I would love to go through all the info before I get started. I want to replace all the rose joints the are all sticky. So I need info on what to use there. There is lots of work for me and lots of photos still to come!
i will not make you dissapointed, but it seem not to have the mast support system. the problem is that it’s not possible to get hold of one now aday. AD#031599 is mandatory to get it airborne. maybe it can be used for hoovering practise, but i assume no one will recomend that.

i would say, it’s only worth the money as the engine value for now, or parting it out.

what do you think?

also, mr fetters have a good point about the hirth engine. M5 was designed for the 582.

what documentation does it come with? assembly manual? other information from rhci? for example, it should have package list, blade grip assembly instructions, centrifugal clutch assembly, tail rotor gearbox assembly, main transmission assembly, sprague clutch assembly, ”reaching the customer” paper and so on, updated rotorhead drawing.
 

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This is my Mini 500's brother. This is also in South Africa. Turbine mini 500
it’s nice.

btw, it looks like turbine helicopter have been hennie roets, serial 264, registration zu-bhc. in kroonstad (but now converted to turbine obviosly) there is another one, serial 223, zu-bra, with a rotax 618.
zu-bra was owned by david maree in florida hills, johannesburg.
Hennie 1’st seem to have used the hirth f30, and David rotax 618, but it has changed over the years.
if remember correct, hennie was very active, did a homepage that is gone now (www.gcs.co.za/mini500)
about spare parts, there is nothing available, exept from scrapped m5’s. in the case with the rear cowl, maybe you can copy zu-bhc or advertice on ebay.
if you plan to copy, rhci used pre-preg, mold and oven to get high quality. i guess to make a copy from a "plug" with hand layup will not produce same quality (my oppinion).
 
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it’s nice.

btw, it looks like turbine helicopter have been hennie roets, serial 264, registration zu-bhc. in kroonstad (but now converted to turbine obviosly) there is another one, serial 223, zu-bra, with a rotax 618.
zu-bra was owned by david maree in florida hills, johannesburg.
Hennie 1’st seem to have used the hirth f30, and David rotax 618, but it has changed over the years.
if remember correct, hennie was very active, did a homepage that is gone now (www.gcs.co.za/mini500)
Look at this. I would love to get hold of him and get the history behind ZU-BRA. I found this vid on youtube and there is another one flying at an airshow in Durban. So would be great to find out what's cooking behind these 2 Mini's
 

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Look at this. I would love to get hold of him and get the history behind ZU-BRA. I found this vid on youtube and there is another one flying at an airshow in Durban. So would be great to find out what's cooking behind these 2 Mini's
try get in contact with both. these phonenumbers are 20 years old:
Hennie: 027825765166
David: 27832978270

this is quite funny, i have saved some of the info from hennies homepage, and what modifications he did. he mention both 618 and F30 so propably he put in 618 first, replaced it with F30 and nowaday it’s a turbine. these modifications are made by the builders themself and have nothing to do with rhci and their recomendations.

after hennie sold his m5, he proceed with other projects. david own majestic air, charter operator. info from internet.
 
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i think you should have the available information published by rhci before getting started. they gave really great advices, for example: assemble of the windscreen, if it's not done correct, it will induce vibrations. so this is really important things to know before starting to put it together. many builders contributed too with valuable information, such as "think about this before you do an assembly".

from "builders tips":
don't use MA300 as sealant between metal filler neck and plastic fuel tank.

another example:
how can you determin if the clutch has been dynamically balanced?
1-if it was shipped on or after june 1997.
2 - if the clutch drum nickel plating has been removed and shows machine marks.

so it's important to have this extra information.

other advices are that a Robinson helicopter have a adjustment and break in period of 5-20 hours, done by a professional company. M5 is no different from certified helicopters, it also need necessary working hours.

attach a pic of the current status of my project. only cabin is put together with pliers.

The Centrifugal clutch does not need balanced. That was an AD before we know what was really making the vibration. We were kind of forced to grab at straws due to customer pressure when a bunch of them were saying it was unbalanced. It turned out to be the ridged belt tensioner pushing the clutch sideways from the torque pulsing of the engine. The solution came with the Mast Support kit fixed that with a spring-loaded idler arm.
 
The Centrifugal clutch does not need balanced. That was an AD before we know what was really making the vibration. We were kind of forced to grab at straws due to customer pressure when a bunch of them were saying it was unbalanced. It turned out to be the ridged belt tensioner pushing the clutch sideways from the torque pulsing of the engine. The solution came with the Mast Support kit fixed that with a spring-loaded idler arm.
many thanks for updating the information.👍 i assume it's of no harm then if it's balanced, improving over-all vibration characteristics. just make a smooth helicopter even smoother.

you know, i really see the fantastic review made by ken armstrong from the 1999 kitplane issue in front of me. i use to read it now and then. everyone should do the same.
 
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