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Governor
#41
Greetings Eddy:
You seem to have a handle on the company structure etc. I have a question, but first you say that CRE is the manufacturer of the MZ 201 and MZ 301 yet they are dependant on Zanzottera to provide the parts. A couple of us have bought and paid for the MZ 301 and in my case I paid for it in February of 2008, almost two years. We have not yet received the engine because Zanzottera, I suppose, will not provide the necessary parts for CRE to “manufacture” them. So if CRE is not allowed to make the parts and only assemble them so that means they cannot either make the MZ 201 or the MZ 301. My question is shouldn’t, at a minimum, mosquito stop advertising the MZ 301 as an option for the helicopter let alone the MZ 201?
Dave
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#42

More info about the MZ301 history:

December 2008 an XE3 was being readied for flight testing. The engine seized and troubleshooting ensued. After much investigation, it was discovered that the crankshaft had been clocked wrong when pressed together (in Italy). No MZ301's could be produced until the crank assembly process could be corrected and proper crankshafts sent (from Italy) to CRE.

That has all been resolved, and an inventory of proper cranks is in stock for MZ301 builds.

I was at the factory yesterday, and saw the recently completed XE3 (with the proper crank). Dwight has an hour test flying on it. Dwight says there are two more XE3's scheduled for completion within the next 6 months.

Dave...I understand you were in line for a MZ301 when the crank issue arose. Maybe there is some confusion about your engine. I would suggest you follow up again and see where the issue is.

My intent in getting in this whole discussion is merely to correct misinformation which could potentially influence potential Mosquito buyer decisions.

I'm not persueing a semantics/language debate, and as such I don't need to "win".

There, you have the facts, so all you potential Mosquito buyers need not be influenced by misinformation. The Mosquito enterprise is alive and well, and growing all the time.

Later,

Eddy

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#43
What in interesting thread this is.

Here are the facts:

CRE manufactures the MZ202. He has several suppliers that provide parts. Some from Italy and some from other places. GM is the manufacturer of the cars they make. They have many suppliers from all over the world. End of story.

Dave, the reason you weren't sent the 301 initially was because of the problem with the crank shafts that were sent from Italy. In the mean time the subject of the 4 stroke I was fitting up came up and so we've been waiting to see the outcome. I now have some hours on the one I was testing and though it works fine and was flown daily at Oshkosh this year I'm not happy enough with it to release it for production. Dwight is trying a different engine now which he is working on as he is able with his very busy schedule. After some testing we will know the outcome and will decide whether we proceed with production or not. R&D doesn't happen overnight and sometimes after a lot of time and money are spent things still don't measure up. But we try again and hope for better results the next time.
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#44
Thank you James, Eddy, and John for all the relevant information. It is as you say, "interesting". It is good to discuss these things to keep a good perspective. Sounds like the company is doing just fine and improving with safety in mind.
Dave
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#45
back to governors. cant you make a proportion type governor. being that fuel (potential energy) is going in to the engine to make the blades spin (kenetic energy). since power required is proportinate to fuel needed, i know you can come up with the ratio. i would make it to reference 100% rpm flat pitch. then make your ratio. for every 1 inch of collective a requirement of the throttle would need to move X inches. there should be a slideing plate at the end of the throttle cable cover to fix to. the throttle will be set to 100% and never adjust any more twist to it. now tie your collective to the slideing plate. as you pull in collective, that plate will move proportionatly. if i looked at it for a day, i could come up with it. mechanical would be the best. it would be small and almost weigh nothing with almost no chance of failure. it would have to work because power is related to total aerodynamic force of the blade which is set by the collective. your rotor RPM will never droop. if anything it might lead you rotor a little. also, if you wanted to fine tune it, you can make it like a lawn mower. make a tiny blower come off you rotor on to a flap that is tied to your throttle. thats a little extreme but simplistic. throttle will be adjusted by the strength of the blower caused by the RPM of the engine.
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#46
Hawk, what you first describe is called a correlator. It is a device that opens the throttle as the collective pitch control is raised and closes it as the collective pitch control is lowered. The Mosquito has a correlator, and it works fine. But a correlator does not accommodate changes in load imposed by the tail rotor, when you want to turn, or the cyclic, when you want to do something other than go up and down.

So a governor is still needed. One of the best mechanical governors is the "flyball" governor. You find these on big old stationary steam engines, and in some lawnmower type engines. They are fairly common on diesel tractors, excavators, crawlers, and parking lot sweepers. Adjusted properly, they work very well, and are very reliable. They are also quite heavy. I'm sure you could design one, or get someone to design one for you, and fit it to an MZ type engine.

As you probably know, the MZ engine line, as well as almost all modern engines use Capacitor Discharge Ignition (CDI) systems rather than the old standby magnetos of yesteryear. That's because CDIs are far more reliable, deliver a hotter spark, are less expensive, and lighter than magnetos.

These days engine governors are also electronic. For the same reasons, weight, cost, and reliability. Electronic governors are also more accurate than mechanical governors. They typically consist of a microprocessor, running some sort of Proportional-Integral–Derivative (PID) controller software. The software is designed for and tuned to the characteristics of the engine being controlled, and the inertia of the load. There is a governor currently available for the MZ202. One is being developed for the MZ301.

Governors for other reciprocating engine and throttle setups planned for the Mosquito line of helicopters will be developed as required. Governors are an integral component of the fuel controls on most turbine engines.

Tom
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#47
you can do all of this mechanically. all you would need to do is observe the amount of fuel needed when applying yaw pedal. do the same for the roll and pitch. you can make the mechanical mix for about three pounds total if i had to guess. try finding an electronic unit with wires at around that weight to do this. this will not fail. the material can be very light and doesnt have to be to strong. there wouldnt be much force applied to this. the force would be equal to the force applied to the throotle on the engine. if anyone wants to try it, let me know. if you are scared, i will test fly it. when i get one of my own, i am going to be a maintenance experimental test pilot for you guys.
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#48
Hawk, a tight RPM control is not possible with a simple mechanical "mixer" which is called a throttle correlator, I think almost every piston helicopter ever made has one. You just can't give it X amount of fuel for a certain situation and always expect to have the exact same RPM. As you call yourself an IP, you should have a understanding of this to some degree already.
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#49
well there good friend, you should know that for the rotors to turn require energy. we use fuel (potential energy) and convert that to Explosions (kenetic energy). the by product of this conversion is heat. this is how you can measure torque on a turbin engine by its TGT. Energy given must be equal to energy required. you can quantify the variables that slow the rotor down. you can do this through observation. the rotor will slow down proportionatly to the amount of energy applied against it. the energy is relative to the TAF. we can measure TAF off of our collective and tail rotor position. again, note how much throttle is needed relative to a collective input or position. do several of these and plot them on a graph. after a few of these done, then come up with a proportion or ratio. when altitude correction was brought up i said that you would have your collective at flat pitch on the ground and bring the rotor to 100%. that has set the density altitude at that time. you can alway adjust for altitude with a little more throttle twist to re-referance to 100% in the air at that altitude. so the only time you need to adjust the throttle is when you operate at a great difference in altitude. i do not know how or why i have offended you but if it is because you havent seen it done yet doesnt mean that it cant be done. i wont even mess with your offense to IP.
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#50
HAWK IP - 12/21/2009 12:02 PM

well there good friend, you should know that for the rotors to turn require energy. we use fuel (potential energy) and convert that to Explosions (kenetic energy). the by product of this conversion is heat. this is how you can measure torque on a turbin engine by its TGT. Energy given must be equal to energy required. you can quantify the variables that slow the rotor down. you can do this through observation. the rotor will slow down proportionatly to the amount of energy applied against it. the energy is relative to the TAF. we can measure TAF off of our collective and tail rotor position. again, note how much throttle is needed relative to a collective input or position. do several of these and plot them on a graph. after a few of these done, then come up with a proportion or ratio. when altitude correction was brought up i said that you would have your collective at flat pitch on the ground and bring the rotor to 100%. that has set the density altitude at that time. you can alway adjust for altitude with a little more throttle twist to re-referance to 100% in the air at that altitude. so the only time you need to adjust the throttle is when you operate at a great difference in altitude. i do not know how or why i have offended you but if it is because you havent seen it done yet doesnt mean that it cant be done. i wont even mess with your offense to IP.

Hawk,

I have to say, I think you are simplifying the situation way beyond what is true. This is my take on the subject.

If mechanical means were able to make the correlator effective as you say, the engineers at all the big companies would be doing it. In the years since Sikorsky developed the first usable helicopters, there has never been a correlator which was good enough to do what you claim can be done.

With their budgets of millions of dollars, they can not seem to get a mechanical solution to work as effective as you say can be done.

On paper, I'm sure it looks like a simple calculation, but in the real world, we all know it doesn't work like that. Just greasing the machine on the maintenance schedule will change the effect of a mechanical correlator.

I advise that you sell your devised system to a large helicopter manufacturer, and you will have the ablity to never need to inspect an aircraft again. This is not a rude comment, just facts.

I worked on Helicopters for 5 years in the military, and another 7 years after. A total mechanical correlator will never work like an electronic governor.

You may build it light, but you will never get it as light as the system currently being installed on the Mosquito.

You state the relationship of power for flight, and many other relationships we already know about. But you do not state the relationship that a turbine (with TGT) has with it's fuel. Turbines already have a regulation system for their fuel to maintain RPM. Piston engines do not.

I challenge you to do what you say, can be done. I will insure you never have to work another day. If Sikorsky, Bell, and Hughes can not do it. I do not see an IP doing it.

This challenge is aimed at the piston engine, not the turbine. The turbine needs no governor, it is built in.

This is not a relationship of energy of flight. It is a relationship of efficiencies in the system. Every helicopter has a different efficiency in it's drive system. That percentage changes constantly. Are you going to build a system that can calculate that?

Quit being simplistic, and start being realistic. If it could be done, I'm pretty sure some company with more funding would have figured it out. Figuring Sikorsky made the first production helicopter, they still do not have a mechanical governor.

I do not question you knowledge of helicopter flight, but I do question you abilities to see the dynamics of the system which puts the helicopter there (engineering wise).

James L
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