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New Lycoming IO-233

Dirtbos said:
No offense intended, but that sounds a bit like political spin that I would hear from a Democrat on Fox News. The LSA rules state "at sea level". Speed at altitude is always a bit higher. I think the aircraft didn't quite achieve the speed "as designed". They were originally quite resistant to wheel pants, as an example. Now it is an option.

There is still nothing wrong with the design. The wing removal and reinstall is just at 4 min. in the video on van's website. That is a great feature. I am hoping that some more speed can be wrung out of the aircraft though.
Click to expand...

No offence taken (other than the Democrat part maybe, since I am a republican;))
I am sure the airplane can get a bit faster since the current quoted speeds are with totally bare gear legs and wheels
I believe that sometimes info comes out of Van's that is not correct (such as we will never offer wheel pants), from well intending employees that are trying to feed the RV communitys thirst for information, but because they are out side of the developement part of the project the info they pass along may not be accurate.

As for speed always being a bit higher at altitiude...that depends on the prop being used (since it has to be fixed pitch). There are three ways to control performance.
-Use a prop pitch that will prevent a pilot ever being able to overspeed the engine in level flight(such as a C-172, etc).
-Expect the pilot to adhear to an RPM limit which will limit max cruise speed (meaning pull back on the throttle if it is able to over speed at the altitude you are flying).
-Use a combination of the two.

The RV-12 in it's current configuration is able to true out at 117 kts up through 12,500 ft. This would likely change slightly with the addition of wheel pants / leg fairings.
 
E-LSA limitations

Scott,

As a private pilot ticket holder, RPM control was one of the first things I was taught. I would hope that Van's would not limit the aircrafts abilities based on that factor (trying to control the pilots behavior).

One of the problems with the current E-LSA version of the 12 is the inability to use a different prop (as I understand the regulations). An adjustable prop (either ground or in flight) would allow a pilot can make changes based on his own flight circumstances, and therefore improve cruise at altitude (hopefully).

From reading the new FAA experimental regulations, it looks like it will probably be difficult for the 12 to qualify as an E-AB (which would give a person that flexibility). There is nothing better than good old government control.

If a person could blend the features of a 3300 Sonex with the features of the 12 (superior cruise and climb of the Sonex with the cockpit size, superior visibility and easily removable wings of the 12) he could have a great aircraft. Some of this relates to the interpretation of the LSA regulations as mentioned before. The Sonex has been approved for LSA based on their interpretation (and cruises at 170 MPH at altitude). It is too bad that Van's has taken the conservative approach on their's.
 
I just do not understand.

Given that:
An LSA aircraft is limited by regulation to have a maximum speed of less than or equal to 120 KTAS (138 mph) with maximum continuous power. An LSA aircraft is also limited to a prop that can not be adjusted in flight and the engine must be normally aspirated.

How then can any aircraft working under LSA restrictions 'cruise at 170' mph at altitude?

Set the pitch the prop (on the ground) so steeply that RMP at low altitude is reduced? But then the engine is not at maximum continuous power.

-Dave
 
Dirtbos said:
Scott,

As a private pilot ticket holder, RPM control was one of the first things I was taught. I would hope that Van's would not limit the aircrafts abilities based on that factor (trying to control the pilots behavior).

One of the problems with the current E-LSA version of the 12 is the inability to use a different prop (as I understand the regulations). An adjustable prop (either ground or in flight) would allow a pilot can make changes based on his own flight circumstances, and therefore improve cruise at altitude (hopefully).

From reading the new FAA experimental regulations, it looks like it will probably be difficult for the 12 to qualify as an E-AB (which would give a person that flexibility). There is nothing better than good old government control.

If a person could blend the features of a 3300 Sonex with the features of the 12 (superior cruise and climb of the Sonex with the cockpit size, superior visibility and easily removable wings of the 12) he could have a great aircraft. Some of this relates to the interpretation of the LSA regulations as mentioned before. The Sonex has been approved for LSA based on their interpretation (and cruises at 170 MPH at altitude). It is too bad that Van's has taken the conservative approach on their's.
Click to expand...


Don't forget...once you are have your ELSA Airworthiness Cert and the accompanying operating limitations...you can change anything on the 12 that you want. You will of course be required to stay within the LSA operating perameters. If you want to change to a Jab 3300 you can do it (or change your prop) you can do it. No re-certification is required....self-regulating though you may be required by your operating limitations to fly off more hours. If you get caught exceeding your limitations....your aircraft loses its LSA status forever.

Pete
 
the_other_dougreeves said:
Eh? Do you suspect there will be no EtOH-free 93 mogas, or is there a federal requirement that all 93 mogas contain EtOH?
Click to expand...
As I understand it 93 AKI unleaded is only made in certain places, all of them east of the Rockies as far as I know, since I have never seen it out here. The highest we have is Shell V-Power 92 AKI unleaded. According to the Lycoming presenter, he said that 93 AKI is made in the Northeastern US.

Once a large geographic area has been taken E10, the oil refineries can drop the AKI of premium unleaded blend stock 3 AKI. We have been told that the highest AKI rating coming out of refineries in the NW will be 89 AKI once they have taken OR, WA, MT and ID all E10. We are currently seeing only 84 AKI blend stock coming down the Olympic pipeline into Oregon for blending 87 AKI regular. There is NO federal requirement that all mogas contain ETOH under EISA 2007. There is only a requirement that each year more and more ethanol be blended with mogas. It is a big economic dilemma. There is a powerful tax incentive to terminals to blend ethanol. Once a terminal puts in the infrastructure to blend ethanol they get a $0.51 tax credit for every gallon of ethanol they blend into their gasoline. They have a strong incentive to take all of the stations that they supply E10. The oil refineries don't have this incentive, but once all of their terminals go E10, they can tune their process to supply "suboctane" product for E10 blending which represents a cost saving to them and more product comes out. We are seeing areas, like Tuscon, AZ, a state that does not have a mandatory E10 law where the terminals cannot order 91 AKI clear stock. Since Oregon is a mandatory E10 state, and we have no refineries, we will see all of our blend stock taken suboctane by the end of next year, in fact the one airport in the state that does sell 91 AKI unleaded on the airport has already been told to expect only 89 AKI by the end of the year.

There is nothing in EISA 2007 that prevents a state from passing a statute that requires all premium unleaded be delivered without ethanol blending. We intend to try to pass such a law in the next Oregon legislative session. It is the only way to protect aircraft, watercraft and all users that require 91+ AKI unleaded gasoline. It is unfortunate that the ethanol companies and the oil companies and the politicians don't understand that unleaded gasoline is a type of "avgas" recognized by the FAA and they don't understand the economic damage wrought by putting ethanol in all gasoline, witness the problems in the marine industry in the NE and CA.

From the DoE EIA, 2007 US production (includes finished imports), millions of gallons per year:
Mogas: 3,051
Jet-A: 528
AvGas: 6

So, Avgas is about 0.2% of total mogas production.

TODR
Click to expand...
I am only passing along what the slide that was presented by Lycoming showed. He said that avgas, 100 LL, represented 0.0001% of all of the gasoline sold in the US. He did not give time frame or any other reference. He mentioned that 100 LL usage was in the 500 million gallons / year. I am having trouble interpreting your figures above. I was under the impression that CA alone used 15 billion gallons of gasoline / year. It appears from Wikipedia that the US uses about 141000 million gallons of gas / year, so 500 million gallons would equal 0.35%. I wonder why the oil industry even messes with it.
 
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DaveLS said:
I just do not understand.

Given that:
An LSA aircraft is limited by regulation to have a maximum speed of less than or equal to 120 KTAS (138 mph) with maximum continuous power. An LSA aircraft is also limited to a prop that can not be adjusted in flight and the engine must be normally aspirated.

How then can any aircraft working under LSA restrictions 'cruise at 170' mph at altitude?

Set the pitch the prop (on the ground) so steeply that RMP at low altitude is reduced? But then the engine is not at maximum continuous power.

-Dave
Click to expand...

I would suggest that you take a look at their website. http://www.sonexaircraft.com/ A number of Sonex owners have confirmed the claimed cruise speed as they advertise. If you look at the following page there is an explanation as to how the 3300 Sonex is qualified under LSA regulations http://sonexaircraft.com/ads/rx/index.html In the body of their explanation, please note that the 138 mph is at sea level and at 75% power (2750 rpm per Jabiru). Max. power is 120 hp at 3300 rpm. Many pilots have told me that the 3300 can be run at 2850 to 2900 rpm continuously with out any ill effects. Of coarse this is beyond the manufacturers recommendation and would be done at the pilots own risk (and most likely is against LSA regulations), but it would probably produce a little more speed. The real downside is that fuel consumption increases a great deal at these rpm settings. Also, as I understand, it shortens the TBO life. This last one would make me very hesitant to exceed the continuous rpm limit. After all, 170 mph is plenty fine, by my book.

The Sonex does have it's limitations but it's cruise speed is not one of them. The 12 is much better in other ways. I am just trying to decide which combination would be best for my wife and I. :confused:
 
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Peterk said:
Don't forget...once you are have your ELSA Airworthiness Cert and the accompanying operating limitations...you can change anything on the 12 that you want. You will of course be required to stay within the LSA operating perameters. If you want to change to a Jab 3300 you can do it (or change your prop) you can do it. No re-certification is required....self-regulating though you may be required by your operating limitations to fly off more hours. If you get caught exceeding your limitations....your aircraft loses its LSA status forever.

Pete
Click to expand...

I was under the understanding that an E-LSA had to be based on an aircraft that had received a "Special Airworthiness Certificate" and could not be modified from the original design combination. If you have found out differently, please refer me to the regulation so that I can research it. The flexibilities you mention would make the 12 more preferable.
 
Dirtbos said:
I was under the understanding that an E-LSA had to be based on an aircraft that had received a "Special Airworthiness Certificate" and could not be modified from the original design combination. If you have found out differently, please refer me to the regulation so that I can research it. The flexibilities you mention would make the 12 more preferable.
Click to expand...

you can change an ELSA ONLY after it is certifed as an ELSA (built to the manufacter's guidelines). you can do it because nothing says you cannot. the EAA will tell you the same thing if you call them. thats why its so silly to worry about wheel pants and stuff....or additional avionics. No you can't change anything before certification and receipt of your operatiing limitations...but afterwards! you just have to stay with LSA guidelines.

Pete
 
Dirtbos said:
I was under the understanding that an E-LSA had to be based on an aircraft that had received a "Special Airworthiness Certificate" and could not be modified from the original design combination. If you have found out differently, please refer me to the regulation so that I can research it. The flexibilities you mention would make the 12 more preferable.
Click to expand...

I love sonex...two things turned me to the 12 instead. I flew one with my wife. We are not big people (170 lbs and 130 lbs) and she had to ride with her arm over my shoulder to be comfortable...its too tight. the other thing is that it has neutral stability....you cannot ever take your hand off the stick....i guess you could autopilot it if you wanted to. my wife flies also so I'm thinkin maybe when i finish the twelve I'll build a sonex to fly alone....that would be a scream.

Pete
 
Mike,

I went to their site, and you are absolutely correct about the reported 170 mph cruise.

From the Sonex site Mike listed:

"Your Published Specs say a Sonex can cruise at 170 mph. Aren't you too fast for Sport Pilot?"

"All Sonex Aircraft models, with all approved engine options, qualify as Light Sport Aircraft. If you look closely at the Light Sport Aircraft Envelope above, you'll see that the FARs define max speed at Vh. Vh is defined as maximum continuous power setting, which is set by each engine manufacturer's operating specifications. The rule goes further, specifying that speed at Vh must be measured under the following conditions: speed in level flight with maximum continuous power (Vh) of not more than 120 kts (138 mph) CAS (Calibrated Air Speed) under standard atmospheric conditions at sea level. In a standard-gear, Jabiru 3300 powered Sonex or Waiex, our CAS under those conditions is 136 mph. Flying a cross-country in a Jabiru 3300 powered Sonex or Waiex, however, we can climb-up to 8,000 feet and see a True Air Speed of 170 mph at 75 percent power, and it's still perfectly legal under the Light Sport Aircraft rules."

But even after studying their site, I still don't have any idea of how this was accomplished and why only Sonex has latched onto this. I do appreciate the effects of altitude on true airspeed and power available.

Regards, Dave
 
Mike,

I think I understand the 170 mph stuff now. Its not the altitude, or the aircraft, its the engine.

For LSA certification they run the Jabiru per the engine manufactures limits for maximum continuous power (75% at 2750 rpm, max power of 120 hp at 3300 rpm).

For reporting cruise speeds, the engine is run at more than maximum continuous power, in other words outside of the engine manufactures limits, (i.e. 2850 to 2900 rpm).

Is the above explanation correct?

What would cruise be if Jabiru's limits (2750 rpm) were followed?

Regards, Dave
 
N1593Y said:
I am only passing along what the slide that was presented by Lycoming showed. He said that avgas, 100 LL, represented 0.0001% of all of the gasoline sold in the US. He did not give time frame or any other reference. He mentioned that 100 LL usage was in the 500 million gallons / year. I am having trouble interpreting your figures above. I was under the impression that CA alone used 15 billion gallons of gasoline / year. It appears from Wikipedia that the US uses about 141000 million gallons of gas / year, so 500 million gallons would equal 0.35%. I wonder why the oil industry even messes with it.
Click to expand...
Yes, my bad, those figures are barrels; 1 bbl = 42 gal. The percentage is still the same, avgas is 0.2% of mogas.

Updated: From the Department of Energy's Energy Information Administration, 2007 US production (includes finished imports), millions of gallons per year:
Mogas: 128,100
Jet-A: 22,190
AvGas: 251

TODR
 
Dirtbos said:
Scott,

As a private pilot ticket holder, RPM control was one of the first things I was taught. I would hope that Van's would not limit the aircrafts abilities based on that factor (trying to control the pilots behavior).

One of the problems with the current E-LSA version of the 12 is the inability to use a different prop (as I understand the regulations). An adjustable prop (either ground or in flight) would allow a pilot can make changes based on his own flight circumstances, and therefore improve cruise at altitude (hopefully).


It is too bad that Van's has taken the conservative approach on their's.
Click to expand...

I did not mean to imply that the RV-12 engine RPM is regulated for the pilot. If it was, then any altitude above sea level would likely produce a lower TAS than the 120 kts max allowed. Also if you proped airplane like the RV-12 so that it just reached max cruise redline at sea-level, the airplane would exeed the max. speed limit of 120 kts.
You mention the desire for a adjustable propeller...In flight is not possible because it is not allowed by LSA regs (if it ends up being possible to certify as E-AB you could put on any prop you wanted to). Ground adjustable would be possible if the S-LSA example was to be certificated that way but it doesn't look like it will. Van probably wants to be sure that at least at certification, an RV-12 actually meets the rules. If a builder chooses to modify it after that, there is nothing in the rules to prevent it but then it will be his problem if someone makes an issue of it, not Van's.

I don't think Van has taken the conserative approach...I think he has chosen not to play games within the rules as everyone would expect from a company operated with a history of integrety and honesty, particularly when it comes to reporting performance #'s.


DaveLS said:
Mike,

I think I understand the 170 mph stuff now. Its not the altitude, or the aircraft, its the engine.

For LSA certification they run the Jabiru per the engine manufactures limits for maximum continuous power (75% at 2750 rpm, max power of 120 hp at 3300 rpm).

For reporting cruise speeds, the engine is run at more than maximum continuous power, in other words outside of the engine manufactures limits, (i.e. 2850 to 2900 rpm).

Is the above explanation correct?

What would cruise be if Jabiru's limits (2750 rpm) were followed?

Regards, Dave
Click to expand...

That has always been my assumtion.
In my mind max approved continous power is just that.
The fact a few guys say it will run just fine at 150 over that means nothing.
If a sport pilot is flying it as an LSA, he is required to comply with the operating limitations at all times (not just at sea-level).

>rant starts here<
One thing that kind of bothers me about this whole LSA catagory is there seems to be many people (speaking in general terms, I am not meaning to direct this at anyone participating in this thread or even on VAF forums for that matter)...any way, there are people that seem to be looking for ways to tweek the interpretation of the rules for LSA so that they can operate outside of the performance that was intended.
If you don't like the performance limitations currently in place for LSA then builld a different airplane and operate it as a private pilot. If you have to operate as a sport pilot, the be happy we now have this catagory available to us in the USA, and operate within the rules.

My main point of this rant...This could easily become the next rule rewrite issue after the FAA is done with the amateur built rules. People within the FAA may even troll forums such as this. A lot of us are peaved (and we should be) that a small percentage of people not following rules that other wise worked very well, are causing what looks to be certain changes in the E-AB certification rules.
This exact same thing could happen within the LSA catagory. I am not meaning to preach doom and gloom. It is a simple fact. If government regulators don't think rules are being followed, there answer always is to make more rules.

Flame me if you want...but I doubt any of us would want to be responsible for the LSA rules being re-evaluated. The whole LSA catagory and industry is designed to be somewhat self regulating. If the FAA felt that was not working (they just anounced they will be doing an evaluation of a bunch of the LSA manufacturers) we can be sure they will do something to make sure it does work.

>End of rant<
 
DaveLS said:
Mike,

I think I understand the 170 mph stuff now. Its not the altitude, or the aircraft, its the engine.

For LSA certification they run the Jabiru per the engine manufactures limits for maximum continuous power (75% at 2750 rpm, max power of 120 hp at 3300 rpm).

For reporting cruise speeds, the engine is run at more than maximum continuous power, in other words outside of the engine manufactures limits, (i.e. 2850 to 2900 rpm).

Is the above explanation correct?

What would cruise be if Jabiru's limits (2750 rpm) were followed?

Regards, Dave
Click to expand...

The way I read it, the 170 mph cruise is obtained at 75% power. I only mentioned the higher rpm ranges because some pilots apparently use them. I would not recommend it (primarily due to decreased TBO, as mentioned earlier). I have clouded the explanation by mentioning these higher rpm ranges and regret doing so. The 3300 Sonex is completely within the LSA regulations. The 138 mph limit is at sea level. The power output at altitude of the 3300 (combined with it's light weight airframe and "slick" profile") allows it to cruise at 170 mph at altitude. They are not using higher rpm settings to publish erroneous numbers. Given the rant in another post, I have created a mis-conception here. I again would suggest that anyone interested go to the second page indicated in my previous post and read it throughly. It is very clear on how they qualified (legally) for LSA with the 3300. The aircraft is well within the "spirit" of LSA.

Ps. Now that I look back at previous posts, post #60 by DaveLS spells it out word for word. It seems very clear and understandable to me.
 
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I also agree with Scott Mc Daniels on this. Thanks to some builders over the years bending the rules of E-AB I will now have to fight to get my RV 12 under the E-AB. class. I have built 2 other aircraft under the E-AB class and the 51 % rule was followed. I want to build the RV 12 the same way ,but I am not sure at this point if its going to happen.


Brad
 
rvbuilder2002 said:
>rant starts here<
One thing that kind of bothers me about this whole LSA catagory is there seems to be many people (speaking in general terms, I am not meaning to direct this at anyone participating in this thread or even on VAF forums for that matter)...any way, there are people that seem to be looking for ways to tweek the interpretation of the rules for LSA so that they can operate outside of the performance that was intended.
If you don't like the performance limitations currently in place for LSA then builld a different airplane and operate it as a private pilot. If you have to operate as a sport pilot, the be happy we now have this catagory available to us in the USA, and operate within the rules.

My main point of this rant...This could easily become the next rule rewrite issue after the FAA is done with the amateur built rules. People within the FAA may even troll forums such as this. A lot of us are peaved (and we should be) that a small percentage of people not following rules that other wise worked very well, are causing what looks to be certain changes in the E-AB certification rules.
This exact same thing could happen within the LSA catagory. I am not meaning to preach doom and gloom. It is a simple fact. If government regulators don't think rules are being followed, there answer always is to make more rules.

Flame me if you want...but I doubt any of us would want to be responsible for the LSA rules being re-evaluated. The whole LSA catagory and industry is designed to be somewhat self regulating. If the FAA felt that was not working (they just anounced they will be doing an evaluation of a bunch of the LSA manufacturers) we can be sure they will do something to make sure it does work.

>End of rant<
Click to expand...

I wholeheartedly agree with this "rant". The LSA class was created to fill a niche that the FAA apparently feels exists. Use it, don't use it...I don't care. But it should not be abused to exploit loopholes (perceived or real), or to try to game the system. That's what bought us this ridiculous proposed rewrite of the E-AB class. More and more it seems that the government sees E-AB as a gift to pilots, or a luxury, rather than as a valuable tool to further the development of aviation industry, commerce, and the goodwill of the general public towards aviation issues.

DO NOT turn the LSA into a grand experiment that failed due to rampant abuse. Let's not use these forums to promote workarounds, exploits, or cheats of the system. If you don't like the rules, either don't play the game or try to change the rules legitimately.

The worst offenders, in my opinion, are the "can't get my medical, looks like it's LSA for me" posters. Unless I'm mistaken, if you have a good faith belief that you wouldn't pass a medical exam, you need to get a medical exam before you can fly on an LSA (or PPL) ticket. In spite of this, the LSA ticket seems to be thought of as the ex-PPL category. Ironically, though, the more of these idiots that openly discuss using the LSA to avoid medical oversight, the more likely it is that the rules of LSA will be changed to require such oversight.

And, no, I'm not telling these guys just to shut up and keep breaking the rules. I personally think that the rules should be followed (although I think that the medical requirements are hard to justify for the average <100hrs/yr private pilot). Rather, I'm saying that those pilots out there that are willing to flaunt the rules should keep their transgressions to themselves instead of working to incite yet another FAA action and spoil it for the rest of us. It is inevitable that once the feds start messing in your business, you're probably not going to like what they do there.
 
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Play by the rules or we don't get to play at all. Don't screw it up for those that are willing follow the rules.

I agree with Scott, Gary, Brad and lawspud. They have all said it quite well.

I would like to build an RV-12 as an E-AB, but with with some people trying to twist the rules, on LSA limitations and the 51% rule, will only make the FAA want to restrict our options even further.

wil
 
It has been fun to watch

It is amazing to follow the process that has unwound on this thread. There is an old saying. "Words mean things". Unfortunately, there has been a tendency here not to "read" the words.

Sonex is not "breaking the rules". If you find the FAA regulations on LSA, it does state that the max continuous is 138 mph at 75% power AT SEA LEVEL. Just because the airframe/engine combination in this case is capable of 170 mph at altitude, it does not mean that any rules have been broken. And just because it is decidedly faster than an RV-12 doesn't mean rules have been broken. If you take the time to go to their website and read the explanation, it is very clear and concise that the combination is perfectly legal. The 80 hp AeroVee/Sonex combination shows a spec of 130 mph at sea level (well below LSA regs) and 150 mph at 8,000 ft. Totally legal, yet faster than the specs given on the 12. In my opinion, Van's has taken a very conservative approach in his interpretation of the rules (and the design of the aircraft). That is his purgative. It is his company.

As I said, it has been fun to watch. :D
 
Wow... talk about thread drift.

I'm not sure whether to post here, or over on the thread which is actually about the RV-12 performance!

Oh well... here goes. I too would have liked to see the RV-12 performance specs be closer to what LSA allows - 120 kts. max continuous cruise at sea level. 131 MPH at 7500 ft. is not quite what I was hoping for. That doesn't make it a bad plane.... just hoping it would be closer to LSA allowed perimeters. I'm still going to Van's in a week and a half to test fly her. :)

However, it is interesting that the S-19 has almost identical specs - and is also rated at altitude... not sea level. :confused: Maybe they have both squeezed what they can out of 100 HP... based on very similar airframes. Both have roomy cockpits, lots of head room, low stall speeds, 900 fpm+ climb, etc. Not exactly racer specifications. I also think that comparing it to the little Sonex isn't exactly apples to apples.

So, in addition to the pants... I am wondering what else Van's can do to pick up a few MPH. I noticed that the lower air intake in the cowl is a little funky. I am wonder if a cowl cleanup would help?

Lastly... don't bother telling us that if we want a faster plane... build something else! :rolleyes: We're just seeing what we can do to get full allowed LSA performance from an LSA aircraft. ;)

DJ
 
Phyrcooler said:
Wow... talk about thread drift.

I'm not sure whether to post here, or over on the thread which is actually about the RV-12 performance!

Oh well... here goes. I too would have liked to see the RV-12 performance specs be closer to what LSA allows - 120 kts. max continuous cruise at sea level. 131 MPH at 7500 ft. is not quite what I was hoping for. That doesn't make it a bad plane.... just hoping it would be closer to LSA allowed perimeters. I'm still going to Van's in a week and a half to test fly her. :)

However, it is interesting that the S-19 has almost identical specs - and is also rated at altitude... not sea level. :confused: Maybe they have both squeezed what they can out of 100 HP... based on very similar airframes. Both have roomy cockpits, lots of head room, low stall speeds, 900 fpm+ climb, etc. Not exactly racer specifications. I also think that comparing it to the little Sonex isn't exactly apples to apples.

So, in addition to the pants... I am wondering what else Van's can do to pick up a few MPH. I noticed that the lower air intake in the cowl is a little funky. I am wonder if a cowl cleanup would help?

Lastly... don't bother telling us that if we want a faster plane... build something else! :rolleyes: We're just seeing what we can do to get full allowed LSA performance from an LSA aircraft. ;)

DJ
Click to expand...

I agree, the 12 Vs Sonex is apples and oranges. It is definitely a trade off.

I would doubt that the dream machine I mentioned in an earlier post is even possible (Sonex speed/climb with the 12s visibility, cockpit room, etc.). The 12 appears to be a bit draggier (if thats a word) and heavier (among other differences).

If your last paragraph is partially in reference to some of my comments, I appreciate your understanding what I was trying to get across. :)
 
lawspud said:
I wholeheartedly agree with this "rant". The LSA class was created to fill a niche that the FAA apparently feels exists.
Click to expand...

My understanding is that the EAA was the organization that initiated the proposal that eventually yielded the LSA rules. I believe the FAA was the mountain that had to be moved - so far as I know, it didn't move of its own accord.

Over the years I have become less tolerant of "rants". This particular rant seems to be founded mostly on fear and unfounded assumptions. The LSA parameters are about as objective measures as one is likely to find in the annals of the legal system, since they appear (for the most part) to be based on measurable physical quantities.

It is no crime to stay within the letter of the law. It is not per se immoral to travel in an LSA aircraft in level flight at 8000 ft MSL at 170 MPH. If anyone here has an issue with the LSA regulations then they can take advantage of the standard mechanisms for petitioning for them to be changed.
 
Wow talk about topic drift. :D

I'll add my 2c.

Lycoming IO-233
Good luck to them, I still like my Rotax 912. (Expensive Yes, but it is all a tradeoff)

Jab 3300 has been discussed before here:
http://www.vansairforce.com/community/showpost.php?p=54348&postcount=14
Bottom line it is a much longer heavier engine 6 cylinders vs 4, you are going to battle to fit it in 12 and keep cg and keep existing looks. Jab motors rev higher means shorter diameter props so tips don't go supersonic. Short diameter props fits little racers like sonex with minimal frontal area perfect.

What about the build experience
I am building a RV12 for the build experience. I enjoy building, especially VANS. Have you guys seen the other kits up close and personal? Talk and visit your friends that is building other kits and add this to the equation.

Pushing the limits of the rules
I don't think there is anything wrong with optimising a design so you can get maximum benefit within its category! BUT STAY LEGAL! If intentially changing to exceed you are missing the point. (Me being in South Africa we are a little behind the times, our sport rules are being written and passed as we speak. Where it will land up we will see. I am going to make VP prop modifications to my RV 12 that can be adjusted from inside the cabin, I am not governed by current FAA rules. If in SA my "modified" RV12 falls then back into our PPL category then that is where I will register it.

If Manufacterers want to bend the rules, guess who the FAA is going to come down on first??? :confused:

Regards
Rudi
 
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Lyc vs Jabiru vs Rotax

Rudi snapped me back on target for a minute. I'll post while it lasts.

The O-233 sounds like a great engine. However, it's little more than a paper engine right now. It's based on the O-235, and that's been a durable engine, but we need experience with the engine itself. Also, it's curious why Cessna hasn't chosen to use it on the Skycatcher - to me, this says that Cessna doesn't think this enging has any advantage over the O-200, which is made by another company; Lyc and Cessna are owned by the same company.

The Jabiru is a good engine in many ways. It's simpler than the rotax, air cooled, dual CDI, single altitude compensating carb (vs dual on 912) so no mixture. The noise is higher pitchfrom the O-320 and O-360 172s I've flown, but the vibration is smoother. Simpler preflight due to no liquid cooling system, uses cheap oil filters and auto plugs, and runs on 91 octane Mogas. Alternator is only 20A, I believe. It is longer than the Rotax. The big problem is the price - $18,400 right now.

The 912 is a mature, well understood engine that is compact, light and fairly maintenance free. It has its quirks (e.g., gearbox, dry sump / oil tank), but in terms of a proven quantity that meets the LSA need, I can see why Van's selected it. Since it's an e-LSA, you can't just slap on a different engine and certify it as an e-LSA. Thus, the selection of the Rotax gives the airplane a higher chance of success.

If you're building as ex/AB, then you can choose whatever engine you want. However, as an e-LSA, Van's can fabricate more of the airplane than allowed under the ex/AB rules - there's no "51%" rule for e-LSA.

Who will be the first manufacturer to use the O-233? All of the cub-clones seem to use the O-200, although some use the Jab3300 and some the 912. The european designs are going to stick with the Rotax. That leaves Van's, RANS, IndUS and a few others.

TODR
 
the_other_dougreeves said:
The O-233 sounds like a great engine. However, it's little more than a paper engine right now. It's based on the O-235, and that's been a durable engine, but we need experience with the engine itself. Also, it's curious why Cessna hasn't chosen to use it on the Skycatcher - to me, this says that Cessna doesn't think this enging has any advantage over the O-200, which is made by another company; Lyc and Cessna are owned by the same company.


TODR
Click to expand...

According to the Cessna folks at Oshkosh this year, they were well aware of the IO-233 quite awhile back. The only reason for not choosing it for the 162was said to be, simply the fact that Lycoming could not commit to the aggressive supply demand that Cessna needed; 750 engines for 2009, and growing.

I still think that it will be a terrific engine, but it may still be a bit heavy for an RV-12. I sure like the track record of it's heritage!!

Tom
 
Lyc-Jabu-Conti-Bombi

Hello
The lightest and best is determined by what the author has. Because there are many liars out there you can't believe every thing.
 
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Back on track...

Lycoming said:
IO-233-LSA Light Sport Aircraft Engine
The Lycoming IO-233-LSA model displayed at Oshkosh is a light sport aircraft engine undergoing final performance and endurance testing. American Society for Testing and Materials (ASTM) conformance will be completed in 2008, and FAA certification is under consideration for 2009.

The less restrictive Light Sport Aircraft classification opens the market to more pilots, owners, airframe manufacturers and builders. Lycoming's IO-233-LSA provides this growing segment with a genuine Lycoming engine based on the reliable O-235 at a substantially reduced weight and size. The engine's 2,400 hour time between overhaul (TBO) is one of the longest Light Sport Aircraft engine TBOs in the market. The IO-233-LSA will be approved for unleaded fuels and automotive based fuels that conform to Lycoming specifications.[/b]
Click to expand...

And here is a picture from the E-mag Air web site of the engine.

I like that they are going to certify it for both 100 LL and auto fuel.
 
Reserecting an Old Post

Latest news states that the IO-233-LSA engine will be field tested this fall. Also, that the first release will be E-AB and they plan to continue through FAA certification. It all sounds good, even to published fuel consumption.

I know! It's too big and too heavy for my RV-12, but I want it anyway. I'll live with 5 lbs. of lead in the tail, if I have to. The Specs are out on it now and it is exactly the same length, 5" taller, and 9" wider. The extra heigth seems to be at the bottom. My worry is, what the extra 4 1/2" extra width on each side will do to the cowling. Will it be a cowling mod, or a total new animal? Hopefully, starting with a standard RV engine mount would simplify making one for the 12. According to the release, either conical or dynafoal mounting will be available.

I've just got to try and make this work!!

Tom
 
IO-233

the_other_dougreeves said:
Rudi snapped me back on target for a minute. I'll post while it lasts.

The O-233 sounds like a great engine. However, it's little more than a paper engine right now. It's based on the O-235, and that's been a durable engine, but we need experience with the engine itself. Also, it's curious why Cessna hasn't chosen to use it on the Skycatcher - to me, this says that Cessna doesn't think this enging has any advantage over the O-200, which is made by another company; Lyc and Cessna are owned by the same company.

The Jabiru is a good engine in many ways. It's simpler than the rotax, air cooled, dual CDI, single altitude compensating carb (vs dual on 912) so no mixture. The noise is higher pitchfrom the O-320 and O-360 172s I've flown, but the vibration is smoother. Simpler preflight due to no liquid cooling system, uses cheap oil filters and auto plugs, and runs on 91 octane Mogas. Alternator is only 20A, I believe. It is longer than the Rotax. The big problem is the price - $18,400 right now.

The 912 is a mature, well understood engine that is compact, light and fairly maintenance free. It has its quirks (e.g., gearbox, dry sump / oil tank), but in terms of a proven quantity that meets the LSA need, I can see why Van's selected it. Since it's an e-LSA, you can't just slap on a different engine and certify it as an e-LSA. Thus, the selection of the Rotax gives the airplane a higher chance of success.

If you're building as ex/AB, then you can choose whatever engine you want. However, as an e-LSA, Van's can fabricate more of the airplane than allowed under the ex/AB rules - there's no "51%" rule for e-LSA.

Who will be the first manufacturer to use the O-233? All of the cub-clones seem to use the O-200, although some use the Jab3300 and some the 912. The european designs are going to stick with the Rotax. That leaves Van's, RANS, IndUS and a few others.

TODR
Click to expand...
http://www.tandtaviation.com/index.php
This is the web site for the plane lycoming is using to test their IO-233. A good looking platform. They have been using a o-235 in this airplane. Interesting!
 
N417AB/RV-8A said:
http://www.tandtaviation.com/index.php
This is the web site for the plane lycoming is using to test their IO-233. A good looking platform. They have been using a o-235 in this airplane. Interesting!
Click to expand...

One detail that is interesting (to me anyway) the posted empty weight.

828 lbs

This is almost 100 lbs more than an RV 12 (relevant I guess since this is the RV-12 forum)

Granted, it appears this weight is with a standard O-235 but I am doubtful that the 233 will even shave 25 lbs off of that.

This is the reason the RV-12 (and many other LSA class airplanes) are using the Rotax 912. When you have a fixed maximum gross weight you have to meet, the only way to design an airplane with good useful load is keep the weight down...I light engine goes a long way towards helping with that.
 
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Before I started flying the Rotax, I had the same prejudices many folks cling to. I would have preferred to have a Lycoming in front of me, because that's what I knew and was comfortable with.

I've got a little bit of time behind the 912 now. Going to be getting a whole lot more real quick. My impressions of the engine are that it runs very, very smoothly (smoother than any Lycoming or Continental I've ever flown), is very quiet, economical to operate, durable, and is superbly suited to the RV-12 and its mission.


We build and fly RVs not because they do any one thing the best, it's because they do everything very, very well. Total Performance. The 912 may not be the best at any one thing either, but believe me, it does everything very, very well.

As more and more RV-12s take to the skies and people experience this engine and its capablities, the tide will turn.

On any other RV, I wouldn't even consider any engine other than a Lycoming, because the airplanes were designed for them. They're the best in this application. If the folks in Williamsport, PA can make a better engine for the RV-12, it would be quite the engineering feat. More power to them if they can pull it off.

I'm sure someday, someone will put an IO-233 on an EAB RV-12. Then we'll get to see. I can't wait for that head to head comparison. It will make very interesting reading. I just love it when folks try to out engineer the guys from Van's.

Mitch Lock
 
Tank Sealant

For those that are or will be using tank sealant soon, here are a few thoughts. It is definitely messy, sticky, smelly and difficult to remove from unwanted locations.
I recently applied a batch on my lower firewall flange. Using the 10:1 ratio, I found that mixing 10gr of the white stuff and 1gr of the black stuff gave me a just enough mix to smear the flange all the way across with a thin coating. After riveting the Firewall Shelf in place, I was left with sticky black runs and drips on the Firewall and the fuselage floor.
I found that using MEK and a lot of paper towels or rags, you can wipe up the mess by continuously changing to a clean damp section of towel for each area. If you don't then it just smears further. I ended up with a nice clean seam with just a trace of sealant showing.
When using MEK be sure to use a respirator suitable for use with vapors. Also use latex gloves or equivalent to keep your hands clean and protected. Vinyl gloves will disintegrate with MEK.
In addition, this stuff has a 9 month shelf life. 2/3's of mine was gone when it arrived, so keep this in mind when ordering. I ordered a quart, but smaller amounts are available. I'll be finishing the firewall and building the fuel soon.

Art Pennanen
 
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