The fins were a factory design to minimize disturbed air at the propeller. Rans does not make this model any more. I flew this for about 20 years... it was a blast!

I'm glad it was helpful. Fly safe!

I'm glad you got some value from the video... experimental aviation is all about learning and sharing! Good luck on your build.

What’s the n# on the S12? I have one exactly like it N24016

N397RS. I no longer own it.

I inadvertently replied by entering a normal comment instead of replying to your question. See my answer in the comment section. Thanks!

​@@rsingh75 Thanks for the reply! I'm rebuilding a S12 Airail and upgrading it from the 582 to a 912ULS. What was your climb rate like fully loaded?

@NileMcMillion With full fuel and 2 lightweight (135 lb each) people, I got about 1,000 ft/min in typical Oregon summers. I pitched my prop for cruise rather than climb.

Thank You!

Thanks! I like that part, too. I like doing stuff like that, but it makes the video long... and people don't like long videos. 🙄

I was a "still" guy most of my life, and capturing the essence of STOL is very difficult in that medium. Video is a recent thing for me. Thanks!

Thanks! I'm an amateur, and I used to call my videography "Why Do I Do This? Productions"... I'm thinking about changing it to " I Ain't Doing This No More Productions"

Thanks! You and Mike did a great job announcing... which made watching raw video quite entertaining!!

I just completed and posted the "highlights" video. Enjoy! : kzfaq.info/get/bejne/r9ubgsmGyrHFYps.html

Filming and posting the raw video was the easy part! The next effort of producing an entertaining short video will be a lot of work. 😵‍💫

You are welcome! We have been flying our RV-12iS for almost 2 years now and truly enjoy it. Tomorrow makes the one year anniversary of our near-engine-out experience, and we plan to make that same flight again... this time with a lot more knowledge of fuel.

You are welcome!

Daniel the warning was to move the mixture to full rich when switching tanks. This warning was given in the AC. The warning is saying that you want to maximize the fuel flow to the engine if switching from 100LL for example to MOGAS. Flying on 100LL you would be able to lean the engine much further. If you switched to the MOGAS which needs to be richer then the engine may quit. What you are really asking is why is this the case. The answer is the MOGAS may be partially vaporized. If you install a translucent tube just before the fuel pump you would see fuel and every so often a bubble of vapor passing through the lines. The pump compresses this vapor back into a liquid but since vapor is less dense, overall past the pump there is less flow rate (See the NOTE below). As altitude increases the atmospheric pressure on top of the fuel in the tank pushing the fuel to the tank decreases and the vaporization of the fuel increases. More vapor results in less fuel flow until you reach a point that there is insufficient fuel flow to keep the engine running. This results in power loss and eventually power failure. MOGAS therefore will require a richer mixture to keep the engine running (if you have a mixture, Rotax does not, Lycoming does). NOTE: On Lycoming or Rotax carbureted engines that only pressurize to a few PSI or even in the case of Lycoming fuel injected models that may pressurize to 1 to 1.5 atmospheres (bar) the pump may not turn all the vapor back into a liquid. Rotax fuel injected engines pressurize to 3 bar (atmospheres ... most cars use 3 bar) and therefore have better resistance to vapor lock. Fuel injected engines use much higher pressure pumps and therefore are better at turning the vapor into liquid. This is why fuel injected engines are much less prone to vapor lock.

Thanks for the compliment! The videos that I produce are just for fun, but this was to share some serious information. If I do other presentations relating to the RV-12iS, I'll post it to KZfaq again. I don't monetize my videos.

@@rsingh75 Look forward to it Ron. Many thanks.

I noticed that too, but (while editing) neglected to place some text on the screen to correct that. What he meant to say was "if you're running AVGAS you're fine, but if you're running MOGAS, you have to do this test".

The Environmental Protection Agency requires "all regulated parties including retailers and wholesale purchaser-consumers" to comply with the RVP standards. I have not seen an exemption for FBOs or anything relating to aviation. I believe that anyone selling mogas (especially an FBO) would need to track their usage in the winter months and somehow use up as much of their high RVP fuel before early May. I hope that FBOs do not stock up with cheaper winter fuel before the May 1st deadline. I say May 1st because the fuel terminals are required to only sell summer blend (low RVP) fuel after that date... in other words, an FBO ordering fuel after May 1st will get summer blend, Thanks for your comments - fly safe!

I don't think it would be reasonable to make a blanket statement that vapor lock is more prevalent in a fuel injected engine Vs a carbureted engine (or visa versa). I believe that its also very dependent on the design of the fuel system and other features of a particular aircraft. As an example, in the case of a Van's RV-12, Rian Johnson has stated that the carbureted version is much more susceptible to vapor lock then the fuel injected one. This may be due to the location of the oil tank (that retains a lot of heat after shutdown) being close to the right side carburetor. RV-12 owners can expect to see more stringent limitations for the carbureted version expected in the upcoming POH and other documents. In the case of a typical installation of a Rotax 912 carbureted engine, there is no circulation of fuel (fuel return) beyond the fuel mixing block. This leaves the fuel static in the line leading from the mixing block to each carburetor. If you have a heat soaked engine and you take vapor lock preventative measures by running the fuel pump prior to engine start, that section of fuel line doesn't get flushed which makes that area susceptible to vapor lock. In my opinion, the vapor lock I experienced was occurring nowhere near the hot engine compartment, which is where most people believe it occurs. My vapor lock (better described as "cavitation") occurred at the dual fuel pump location in the tailcone area. This was caused by the low pressure of the pumps sucking fuel from the tank at . I say all this because at this point in the fuel system, it wouldn't matter what type of engine (injected or carbureted) was installed firewall forward. I'm glad you enjoyed and got something out of the video. Thanks for your comments!

@@rsingh75 Does this experience make you want to stay away from mogas in your rv12?

I just noticed that one of the sentences in my response was messed up by KZfaq. Every word that I had underlined got removed. It should say: "This was caused by the low pressure of the pumps sucking hot volatile fuel from the tank at low atmospheric pressure."

@@1dullgeek No, I'm actually still comfortable flying with Mogas. I just assume that I have the worst case fuel and behave accordingly. In cool conditions (OAT, fuel temp, non heat soaked engine) I use 100% mogas. In warm/hot conditions when I expect to fly above 6,000 ft, I fly with a mixture of mogas and avgas. Several people after my presentation told me that they will just switch to avgas and do the added maintenance... which is reasonable.

@@rsingh75 That seems reasonable to me.

Thanks for the compliment Chad! Rian and I are thinking about presenting this at Airventure this summer. Email me ([email protected]) for my other contact info if you fly in to 7S5 - it would be fun to catch up.

No, I had it painted by a person in Bend, Oregon. If you would like his contact info, send me an email at [email protected].

Hi. flew from our home in Independence to Twin Oaks, Pacific City, and back.

Thank you!

Thanks! I suppose it was a photo-bomb... but I was too busy grinning to have noticed at the time!