skyraider71

What do ya'll think of the AP hornet .09? I'm thinking about building H.O.B
Decathelon. Also, I'm starting a Herr Star Cruiser Project this weekend,
I'm considering Tail dragger and a four channel wing mods.

flying poodle

I don't own one, but I think the majority of people that do wish they had gotten the 15. It is almost the same weight, although still somewhat anemic for a 15.

foresterxt

My Feedback: (35)

I've got one and I like it. I haven't used it in a while now, but once broken in, it runs great. It does take a while to break in however. Given the choice, I'd get the 15 since they're the same size/weight.

build light

Typically it seems most .09-.10 engines like this one weigh pretty close to what most typical .15s weigh but produce less power as you can understand.
.15 size engines are a much better choice. This has been based on a power to weight ratio comparison. However I do not have the figures on this to back it up.
Opinions of course may vary!

Add to this there are some really good .15 size engines that can really walk the dog!

It seems that in past years more attention has been given to the .15 size as compared to the smaller .09-.10 CID or the larger .19-.29 engines.

Robert

MJD

My Feedback: (1)

For sure - since .09 or .10 is an in-between size relative to any AMA or FAI classes, in the realm of 0 - 10cc engines it seems that in the past little energy was directed towards discrete products in those categories. I would imagine that is why it remains an in-betweener to this day, where it exists, but in a package that more closely resembles an engine with 50% more displacement in everything but power output.

It would be nice if there was indeed a "small block" 1.5-1.8cc engine, and if it was an affordable "full-feature" R/C engine, i.e. good speed range, power:weight ratio, effective muffling, muffler pressure, no weird fuel requirements, general manners. But, what company would spend the R&D money these days for a fringe product? Unless perhaps the turnkey ARF trainer and second-airplane manufacturers decided there was a market in that size range.

I guess a pertinent question to throw up in the air is, what is the basis of a desire for engines in this class? To power lekkie ARF conversions, or to hop-up 1/2A size aircraft, or... what?

MJD

combatpigg

My Feedback: (3)

The ratio of value to production costs must be what is really why the .10 plays 2nd fiddle to the .15.
2/3 the power but 90% of the cost.
The range of models that the .15 is well suited for has to be at least twice what the .10 can handle.
The .15 can handle a 8 inch prop with authority and the difference in thrust between 7 inches and 8 is huge.
I think alot of value minded shoppers who are working with next weeks' paycheck see the slight price difference and see the choice to go with the .15 a no-brainer.
If the CG is adjusted correctly to accomodate a .15, most 1/2A commercial kits will fly just fine. The complaints about the .15 conversions sinking like rocks, falling out of the sky, etc. have alot to do with being nose heavy.

MJD

My Feedback: (1)

I've tossed .15's in a few 1/2A birds myself, and they worked just fine. Well, I did flutter the elevator off my Mini Fledgling - I was flying it 2 channel R/E with an OS Max .15, and after a few flights it flew in a long dive into terra firma. Up until then it flew great. My OS .15 pusher Astro Blaster was a hoot. Used 25% fuel and a Zinger 7-4 pusher, and I had modified the muffler to exhaust backwards and took out some backpressure while at it. Flew like a bat out of heck, although it landed hot with the wing loading it ended up at.

Anyhow.. it would be cool if there was an engine a bit smaller and lighter lighter than current .10/.15's, that acted nicely and had a high power to weight ratio.

MJD

skyraider71

If the Yellow jacket .15 weighs the same as .09, seems like a no brainer to me.

combatpigg

My Feedback: (3)

Why not just buy OS and know for sure you are getting the best deal?

skyraider71

Good point, I love my O.S. .46 AX's The first engine I ever bought twice! Instead of spending
$80. on a chance, I spent $110. on a sure thing. I'm sure O.S. .15 just as good!

combatpigg

My Feedback: (3)

The most expensive way to do this hobby is to try to do it cheaply.

skyraider71

How about LA .15 in H.O.B. Spacewalker?

combatpigg

My Feedback: (3)

That would be about as good a match for a .15 as you can get. It will end up very sporty at 2 pounds or less. The product review I read looked impressive, but I would not cut lightening holes anywhere. I'm not sure, but it might require moving the firewall back slightly to get the spinner backplate lined up correctly in the side view.....no big deal.

digital_trucker

The Cloud Ranger I'm flying is now tipping the scales at close to 30oz now with a .10LA (yeah, it's a led sled). I imagine a .15 in that Spacewalker should do very well.

skyraider71

Sounds like my kit backlog just got longer!
My club thinks anything smaller than .40 size has to be electric.
Phoey on that!
Starting Star cruiser tonight. I'll post pix when done.

combatpigg

My Feedback: (3)

I just got back from flying some 3D with a 28 oz plane powered by a OS LA .15.
8x4 MAS and 30% helicopter fuel. It is going to take the rest of the summer to find out all that this plane is capable of. It has even done some [ugly] knife edge loops. Let your friends have fun their own way...but I'm here to say that you can have a lot of fun with .15s.
Yes, the equivalent electric plane with a 11 inch prop will be easier to 3D and more impressive, but so what?

SST

My Feedback: (2)

The best .10 you can buy is a Norvel .074...

flyinrog

My Feedback: (1)

CP that is very taco-ish looking as a 3-d plane...the HOB is usually a pretty heavy built kit,, I have a .15 OS on mine and it flys well.. I have a .10 for my spacewalker, but havent finished it yet....Rog

airraptor

My Feedback: (66)

he HOB Decathelon is a big kit for 1/2a i have one still in the box and I will use a OS 15 in it. i even thought about putting a OS30 four stroke in it.

BUY the OS 15 for it and then send me an email or PM and i will help you pick up 1000 rpm in that engine with no grinding on the sleeve at all. just some carb mods and stuff.

skyraider71

I sold my Norvel .074 n.i.b. 5 years ago, big mistake! I'm taking everyones' input into
consideration. I'm glad to find out small engine modeling is still alive! O.S. .15 with
either on of those kits seems to be great combo. It will fit my budget,work shop,and
vehicle perfectly.

flutter caused it

I started with a brand new AP 09 on my Herr lil extra and although it did fly, it was very under powered. Anything more than a slight positve climb and it stalled. I installed the AP 15 since it was exactly the same bolt pattern and this made all the difference. It will fly straight up verticle, barely. Im using a small 2/3aaa battery pack and five 9 gram servos. My all up weight less fuel is excatly 28.2 oz. Using 15 percent fuel in the stock tank gives me 5 1/2 minutes. Mine is more tail heavy than most people would like but it slows down to a crawl while landing. My friend had an o.s. la 15 on his Carl Goldberg Laser and the AP turns 1500 rpms more using the same 8/4 prop and fuel.
Forget what you've heard about drilling out the carb barrel on the AP engines as this will leave you with an engine that WILL NOT idle. The thing is that the AP engine does not have a low speed idle adjustment at all. Not even an air bleed. Therefore you high speed adjustment also affects you idle. Drilling out the barrel means you have to close the barrel more to acheive the same idle RPM which throws off the whole mixture. You can enlarge the barrel but ONLY by egg shaping the hole. The egg shape or oval must be from side to side while looking straight down the carb. Precise use of a dremel will net you about 1800 RPM increase when using a 8/4 prop. M

skyraider71

Does the Herr l'il extra fly like my Somthin' Extra? They look very similar.

airraptor

My Feedback: (66)

LOL i have a OS FS 30 four stroke on my laser. hovers at around half climbs very good on 11.5x4.5 pattern prop at 11,000 on the ground