You know the more I think about it the more I agree with Archie and Ed.....
using the SAP in the lower classes where a guy needs to develop his craft, meaning, must fly a lot, makes sense. It will be the most cost effective way to learn pattern flying.

I know my set-up works fine in masters flying but in the higher classes, one needs every advantage he can get to get scored well. With the advances in electrics and the sound quality they produce, a 2 stroke whine is probably out of place. It seems to me I would need to outfly an electric by considerable margin to score as well. So it is perception; as much as I hate to admit it as head judge, people's perceptions are uniquely personal things. It's not supposed to matter but I believe it does

Okay then, back to working on Aesthesis...she's almost ready for clear coat

Matt,

Todd has got the engine pretty much dialed. Pattern is certainly a tough testing ground for "the little gasser that could" and hopefully we will be able to figure out what is causing the front bearing to wear prematurely... whether it is the mounting method, or simply the way we run it.

No mention of this yet in the sport thread, but then I don't think there are any guys there who have nearly as many hours of run time on their engines as I have on mine.

BTW, I downloaded a little memo app for my Droid so that I can better document how many flights and how much run time I have on SAP #2. I estimated 200 flights on the first engine, but Anthony R thinks it was closer to 250. I had been flying it almost every chance I got since January - usually doing 5 and sometimes 6 flights per session - so 200 may have been a conservative estimate. I stopped making any real effort to keep track after the coupler issue was solved, after about flight 120 or so.

I get the Pennzoil 2C oil from oil-store.com where 24 8-oz containers sell for $26.95, plus about $8 for shipping. One bottle per 2-gallon Blitz fuel can and I'm good to go.

If you have the Aesthesis ready for the Oasis Fall Finale I would love to see her fly! Sounds like a good K-Factor cover, so I will bring my good camera gear!!

Ok, just picked up 2 gallons of Sunoco NASCAR gas at NHMS. It is the very same stuff the Cup cars ran a couple of weeks ago, and is 100 octane, 100% unleaded gasoline. I will add some RP syn at 50:1 and see if it picks up a couple of RPM. BTW, it was $9/gallon.

Hmm... wouldn't the RPM's decrease unless the compression ratio is increased??

Admittedly, my understanding of these things is rudimentary, and probably incorrect...[sm=what_smile.gif]

No, the energy content is the same, regardless of octane. However, 100% gasoline has about 4.5% more energy than 90-10. If we could buy 100% 87 octane gas, it should be the same as the NASCAR gas on a relativity low compression engine like this.

It should work similarly to the 100 Octane Aviation gas I used several months ago. The engine timing retarded enough (slow flame propagation) to make the engine appear to run fat.

BUT I really would love to hear if it runs differently on gasoline intended for surface vehicles. AvGas has additives for high altitude runs that should not be required in gasoline intended for ground runs. Please report here

Thanks

I have a DLE-30 on a test stand that I can do back to back runs on, with a digital tach.

Gary, as an experiment that will be interesting.

My goal is to see what can be done with good ol' commonly-available pump gas. I don't have the facility for a test stand so it would be of great interest to me to see the difference you find between 87- and 93-octane pump gas.

I'm getting around and perhaps a bit over 9K rpm with 87 octane (10 % ethanol), which isn't too bad!

MTK... Just curious with your hours on the engine.  Can you figure out the money savings running gas over glow.  I bet you paid for your setup a couple of times over by now.

Well, this test will be a little while. I am just getting to maiden my new MX2 with an OS GT-55and the ignition box died. So I put the DLE-30 box on it and it runs. I sent the OS ignition back to Tower, so who knows when I will get it back, arg!

Sure, I used about 10 gallons of gasoline all total at 2.50$/gal roughly, plus a 8$ container of oil for each 5 gallons. That's about 41$ for 10 gallons of mixed gasoline. About 150 flights total on two engines and three airplanes, at about an avergae of about 18 minutes per flight or about 45 hours of operation.

Equivalent glow fuel for me was 20%nitro at about 22$ per gallon. 45 operational hours on glow would require about 14 gallons of fuel. That's 308$ for fuel plus tax of 7% or just under 330$. The savings is considerable over about half a season of flying. I essentially stopped flying a month ago when I dorked my Temptress and just got her flying agin last Saturday.

We have had some hic-ups here and there with the gas engine but that's normal part of the learning curve in my opinion. We had to learn how to care for the beastie and feed it and treat it right.

Therefore, to summarize, if one flies about 20 gallons of gasoline in a season which is very realistic for pattern, expect to save around 500$ or more over glow standard fuel (less than 20% nitro). If one runs a YS170 with its 30% thirsty habit, the savings are closer to 800$ per year. (45 operational hours with a YS will consume about 30 gallons of 30% at 30$ per gallon, MINIMUM) I exclude any maintenance costs

As we have said before, this approach is great for the guys who need to fly a lot or just love to fly a lot. No, it doesn't make the power that YS170 does but it really doesn't matter in the lower classes up to Advanced.

Guys flying in the lower classes always try to emulate what the top dawgs are doing and that's an expensive shame. Their costs skyrocket due to lack of experience in buying stuff they don't need. They wind up learning the hard way...we all learned that lesson. Many simply drop out on cost alone

As I stop and I think about it, this gasoline alternative makes an awful lot of sense in easing the pain of the pattern learning curve. I mean I had a sense of some of this stuff when I embarked on this journey 9 months ago but it actually has turned out to be better than expected. Again, not trouble free, but heck don't they have some problems?

BUT... now that the combination has been worked out, anybody can have a (for the most part) successful installation with ease. My recent engine swap-out validates this, and after only 11 flights I am already getting excellent performance... even very good throttle response.

True... The set-up is straight forward and detailed enough for a total noob to gasoline engines to be successful.

Anyway, I am committed enough to the SAP at this point in time to put a little lettering on my new Aesthesis design

Here she is with nearly all of the lip stick and rouge but before final clear coats:

VERY COOL! [sm=thumbup.gif][sm=thumbup.gif]

The anhedral stabs look great... supposed to improve tracking in outside maneuvers, no?

Will you maiden with the cheek winglets, or without?

Matt,
very Nice work ,

Thank you,

The canards are removable so I will fly the crate both ways and get feel for the whole envelope delta. I am very curious to see how the SAP does with this plane. It is coming out nice and light so we'll see what the draggy airframe and lighgt weight combo does.

Anhedral tends to allow more stab effectiveness for all attitudes of the plane. I am only using 4 degrees which is less than some other designers have used

Thank you Bryan.

Not much compares to your finishing but I can only dream. One thing I found out during the finishing process is that since last time I finished one (Temptress, 8 years ago), the fine touch and eyes have gone south a little. Must be getting old.

I hope I can see this scheme in the air better than I could my Temptress.

Hoping for clear coats this week and flying maybe next week, depending on work schedule. There is a business trip in there somewhere so final finish and rub out may need to wait.

Very sweet looking plane!

Thank you.....4 years and a bunch of life changing events during the process, but I satyed with it and it's practically done

Certainly hope the next design takes less time

I have a Syssa 30 with the stock muffler including the noise reducing inserts and plan to start with a Vess 18x6.

Will I be under 95 db at 10 feet? According to Todd's website it should be easy, but I wanted to confirm since Todd's numbers seem a bit optimistic.

From the Syssa website:

"Sound tests (per AMA test guidelines): 96 dbA without SAP muffler tone insert, 91 dbA with SAP muffler tone insert"



thx

We have not run stock mufflers on the SAP180...only tuned pipes

I fly the SAP on a Giant Super Sportster and have at least 80 hours on the engine. I have been averaging a gallon of week through it since Feb, with only about three weeks with zero flying due to trips. I don't have the soft mounts. Most flights are 15 min. mostly at half-trottle with lots of touch and goes. I also do my 1970's version of the "pattern", but not well. I do WOT on the up lines and close to idle on the down lines. I also do a lot of "yank and bank" which puts a great deal of force on the front bearings.

A while back, I did have a spinner bolt break and fod the prop which broke in half. The engine ran for two or three seconds before I got it shut down; got the plane back to the runway with no problem. I was concerned that the brief run with only half a prop may have damaged my bearings. That is the only hit to the prop the engine has ever had.

I have noticed some slight movement of the spinner and prop tip. At the tip of the 18" prop there is about 1/16" fore and aft play.

Did you notice any end-play before your bearing failed?

No, I didn't really notice anything before the failure, except that the day before there was an unexplained hiccup where the power dropped suddenly for about a second and then picked right back up again. I didn't notice the spinner movement until after the serious power loss the next day.

Glad to hear yours is holding tight. I didn't think anyone else had as much run time as I did!