Compound turbo

[TMann]

You second what?

The quote is in post#20.

I believe you will have to build one and prove that to the rest of us.

I don't recall that being a requirement.

[Steve Innova]

Mistral is working to reach a certified status on their 3 rotor version.

But really, who cares if Mistral succeeds in certifying their engine? Their engine is MORE expensive than the proven Lycoming, and has LOWER fuel efficiency. That, with the unfavorable Euro - $ exchange rate make the economics unviable.

 

If they were well financed and willing to produce and sell the first several years of production (100s - 1,000) engines at a loss to directly compete on price w/Lycoming, then they could have gained enough market share to be commercially viable. But they wont, so... so long Mistral.

[Lynn Erickson]

Mistral is working to reach a certified status on their 3 rotor version.

 

It seems to me that at one point in time, there was a certified rotary available.

AT any rate, the RV boys seem to be running with them.

If they do certify it it will be more then a continental 550 . so why would any one buy it. and even if it is certified what does that mean to the homebuilder with a cozy looking for behind the firewall design that he can trust to put in for the family. there is no doubt that a rotary engine will run. it is, will the support systems keep it running? electronic systems used to support the engine are the biggest challenge. there is not yet one system that is proven to be even 90% reliable. the engine has very few moving parts. the gear box very few parts, the mechanical fuel systems are very good. the electronics system have thousands of parts, not to mention all the little electronic and computer bits floating around in there and all it takes is one to be out of place and it will ruin your whole day.

[argoldman]

If they do certify it it will be more then a continental 550 . so why would any one buy it. and even if it is certified what does that mean to the homebuilder with a cozy looking for behind the firewall design that he can trust to put in for the family. there is no doubt that a rotary engine will run. it is, will the support systems keep it running? electronic systems used to support the engine are the biggest challenge. there is not yet one system that is proven to be even 90% reliable. the engine has very few moving parts. the gear box very few parts, the mechanical fuel systems are very good. the electronics system have thousands of parts, not to mention all the little electronic and computer bits floating around in there and all it takes is one to be out of place and it will ruin your whole day.

Lynn,

Out of curiosity, are you including Tracy Crooks ignition/fuel systems in your sample of the above. What is your definition of being 90% relliable, how soes that compair with the same criteria used to assess the reliability of magnitos and mechanical FI and carbs. What data are you using to support the claim?

 

I am trying to decide. Your input will be most helpful.

 

Thanks

[Lynn Erickson]

Lynn,

Out of curiosity, are you including Tracy Crooks ignition/fuel systems in your sample of the above. What is your definition of being 90% relliable, how soes that compair with the same criteria used to assess the reliability of magnitos and mechanical FI and carbs. What data are you using to support the claim?

 

I am trying to decide. Your input will be most helpful.

 

Thanks

there is no engine system that is 100% reliable. I have seen numbers from 99.9% claimed by manufactures to as low as 90% from accident report data on certified equipment. there is no real way to know the number on homebuilts using any of the engine systems. I have not seen a system that is as reliable as the lowest percentage of the certified systems. Tracy and the like may have a good systems but remember when they were not so go? they were selling those as airworthy. their current systems are only an improved model of the older system. their new systems are maybe an improvement. the key word being Maybe. why did they have to make improvements to the old system? how many flight test hours do they have on them? has anyone flown one system for 2000 hours. I would say no! how many certified systems have gone 2000 hours? the certified systems like mags and airflow FI are not perfect but at least manufactures have TBO's, maintenance schedules, procedures, and updates. do the homebuilt systems have these. not to much! look at this new E mag P mag thing. thats just dam dangerous. lets just hope no one gets hurt from those new Wonder mags that keep failing. I'm not saying don't experiment but if you do know the risks. I contend that most homebuilders have no real idea of the risks involved to test fly their machine until they have done it. Hence the Hanger Queens or four place planes that are now single seaters until they work all the bugs out. and when they Think they have worked out the bugs they can fly with their family and friends.

[dirtdox]

I have had several RX7's and still have one that I drive and a parts car or two. I do like the smoothness of the rotary but if you have never had a rotary you may not realize some of their quirks and failure modes. When I first contemplated building an aircraft I was pretty set on using rotary. Now I think the best choice is the proven Lycoming install.