CDignition

My Feedback: (9)

lol..I thought this just happened..I didnt check the original post date,lol...well, im glad you have it all working good..

Kregg

My Feedback: (45)

Very interesting thread if you can make it to the end.... A lot of chest puffing going on.

Perhaps you can provide some direction for me. I also have a CA 2.6 Extra 330L with a brand new DA 100. It has not flow yet since I'm waiting on my Duralites. My question is should I remove the baffling that the instructions indicated very clearly. I do not have an opening directly under the carb (see pix), but there is a opening just fore and aft of the carb. Will this create a problem and should I cut another hole as indicated in red?

FYI: I'm not new to big gas engines or DA's. I have a large Pitts w/ a DA150

mu2driver

My Feedback: (15)

Its hard to answer this question because everyone has cut out there holes differently, and all with good results. Leardriver just happened to have a very misfortunate accident, one which anyone could have had. As far as the baffeling being the culpret, im not too convinced.

I just followed the recomended directions and cut the hole directly under the carb, and installed a single plate baffel as yours.

Do you have a choke servo? If not can you reach the choke from the hole you cut? If so then I would say "Go For It"!
Just be sure to run the engine real good.

The only thing I see on your cut out is the airflow seems it will be directed right at the carb, I dont kno wif this is a good thing or a bad thing? I have heard both sides of the argument...

CDignition

My Feedback: (9)

I never even cut out a hole in my cowl..I made a rod for the choke, but no air can pass there, and I have had no problem...Plenty of room for sucking air..

Mokken

My Feedback: (63)

To many pages to read.. What ended up happening? I had a similiar problem with my ZDZ 80 and it turned out that the clunk came off the fuel tubing in the tank. What happened with this guy?

greenboot

My Feedback: (1)

At the recommendation of his psychiatrist he pitched his computer in the Atlantic and is enjoying his new plane.

Tom

ram3500-RCU

My Feedback: (221)

Read about 4 posts back.

Leardriver

My Feedback: (12)

KERPLUNK!

Learpilot

vatechguy3

My Feedback: (11)

leardriver,

i'm glad to hear everything is working out for you now.

1 question - i am getting ready to order a new da 100 for a 35% carden. now that you've got yours running good, what did you end up with as far as baffling and entry/exit holes in your cowl??

thanks
tony

Leardriver

My Feedback: (12)

Well I have not yet installed baffles in my new one but I am going to....just aven't gotten around to it yet. As far as the cut out in the bottom I have about 1 1/2 square cut out slightly aft of the carb per Dave Johnson. Of course there are also cut outs for the exhaust stacks.

Leardriver

Bill Mixon

I probably shouldn't post to this thread, but I was reading over some old threads and after reading all this I couldn't resist.

Leardriver, posted rather bluntly to Shortman I think it was that he didn't understand and that the plane was not in a harrier. Yet Leardriver is the one that posted that the AOA was approx 30 degrees. I'm sorry but 30 degree AOA is a harrier...

Regardless of all that BS, I'm sorry for your loss and am glad to hear that you got anther plane in the air.

mu2driver

My Feedback: (15)

Only if your going slow, other wise for an aerobatic plane that is just a climb.

you know the C-130 with Rato/Jato climbs out in a 45 degree AOA untill it reaches 1500agl. Is that a harrior as well?

Leardriver was just doing the average aerobatic take off, and being a new plane he was climbing like a bat out of hell, to get as much space between the ground and his plane, in as short of time as possible.

Heck im guilty of doing 90 degree climb outs, straight up

Geistware

My Feedback: (16)

I was wondering, if adding the baffles to the installation changed the airflow of the air around the carb to cause the engine to either starve itself or flood and die. If I remember correctly, you said that it flew OK until after you added the baffling. Cound the baffle effect the pump in the carb? You would not see the problem until you are flying.

Stratos

My Feedback: (4)

You guys can't let this thread die, can you??lol

AOA is the angle between the direction of travel and where the nose is pointing. There is a more scientific way to say this
but I hope you understand what I mean. In other words a C-130 climbing at 45 degrees still has 0 AOA.
I mean, anyone that has played and read the manual of an air combat simulator should know this

Again, baffles had nothing to do with what happened to Paul. He was using a glow rated inner diameter tubing and fittings and while
it was working fine when he was gentle with the throttle it caused the engine to starve and die when he started being frisky
with the left stick(punching it for the takeoff).

BTW, since that unthinkable thing happened, Paul has being flying another 2.6 with great success and he is getting ready
to put together a 3.3 Yak. In other words, he has moved on. Why don't we??[sm=tired.gif]

Stratos.-

us020140

My Feedback: (28)

I haven't read all the posts so I hope this isn't redundant. My BME 50 routinely flames out on take off as soon as the nose is pulled up unless I really let the sucker warm up on the ground...at least one minute.
Phil

DKjens

My Feedback: (50)

Phil,
Sounds like a lean low end. Try richening up the low end 1/16 - 1/8 turn.
DKjens

Bill Mixon

AOA and angle of climb are two different things...
I notice you user name is Mu2driver. Please don't tell me that you fly a full scale Mu2 and believe that 45 degree AOA is the same as a 45 degree climb.....????[X(]

mu2driver

My Feedback: (15)

OOPS my bad...

I was thinking of the climb and not the aoa... oh yeah and it was 8/20/2004 4:16:06 AM when I wrote this... very bad night for me[8D]
Please forgive my ignorance...

Leardriver

My Feedback: (12)

My god I can't believe this thread is still rearing it's head! Ok...maybe I should have worded it better. I was climbing out fairly aggressively? Uh..the angle of climb was 20-30 degrees? It's been months and I haven't honestly revisited the entire incident for some time. Yea I spose I was a bit short with some of the guys who really enjoy second guessing what happened.....despite the fact that they were no there. That was never the reason I posted to begin with...I was trying to figure out why the engine quite to begin with so it wouldn't happen again.

The only thing we came up with was what Stratos mentioned....I bought a B&B 32oz tank and didn't think twice about using the fittings that came with it...they were 1/16" and I am still not sure that was the reason. I think it had an effect but there is no way to prove it at this point. It was just coincidence that the baffles were installed for that flight. My new one has been running perfectly for several months now so what more can I say........

Anyway, I am not going to post anymore on this thread as it truly has run it's course. If anyone wants to pm me feel free.


Thanks,
Leardriver

Stratos

My Feedback: (4)

Promises promises....

Seriously though, I think you said that already.. ahhh ... more than once....[sm=stupid.gif][sm=tongue.gif]

forestroke

Greenboot - I know where your thinking is flawed. What you are neglecting is the time it takes to reach that point. You are assuming that the plane has no inertia, the power created by the engine, which is fully used to propel the airplane, is equal even at differing RPMs and it takes no time to transition. Then your statement is true (albeit only theoretically).

What you are arguing is that when the airplane turns downwind, given the same throttle setting, the prop will unload and turn at a much higher RPM thus maintaining the original airspeed. When you turn upwind, the prop will load up and turn slower. Always maintaining the original airspeed.

You mention shear... under your assumptions, shear makes absolutely no difference. If there is a change in wind velocity, your hypothetical airplane will immediately adjust.

Now... in real life, it takes time to accelerate. So if are turning the corner and you lose power, nothing helps your plane adjust to the changing conditions, you essentially are up s***'s creek without a paddle.

Greenboot, you are a funny read, though.

Leardriver - sucks to lose a plane, sucks worse if you can't figure out why. I hope you have better time with your new one.

onthefly

Well I'm jumping in here really late. Just finished reading the entire thread. I'm glad that the thread was never closed as there is a lot of good arguments that explain theory. Fortunately many of these controversy threads have a lot of comments that are very educational, as if the winding of the thread isn't itself sometimes. My father retired from the USAF, a pilot. His understanding of aerodynamics is of course very good. But he just "isn't there" when it comes to RC. He likens full scale to models too much. So my question is, do all aerodynamics that we encounter in the hobby mirror what is seen in full size? Where do we most see deviations/differences? Forgot to add, I'm a doctor, of the MD type so I'll do my best not to be a know-it-all[sm=wink.gif].

greenboot

My Feedback: (1)

Very good question. The aerodynamics of RC and full size are identical. How could they be differant? How could the air molecules know if the pilot is inside the plane or standing on the ground? If a full size plane were controlled remotely (or by an autopilot), do you think it would start to behave differently?

Of course size does matter somewhat. But not as much as you think. And giant scale planes fly surprisingly similar to full scale.

The big difference with RC (pilot standing on the ground), is that the pilot "sees" the planes groundspeed directly, but must mentally visualize what the airspeed is. This can lead to confusion, especially when flying in a strong wind.

Tom

sillyness

My Feedback: (25)

AOA is the angle between the free-flow airstream and the wing's chord line (line between the leading and trailing edge of the wing... right down the middle of a symmetrical airfoil). The steeper you climb out, the lower your AOA... as you increase your pitch your thrust creates more and more of the force that opposes gravity. Therefore your wing has to produce less lift. Given a constant airspeed, the wing decreases lift by decreasing AOA. So... you actually DECREASE AOA to climb (after you generate the initial pitch up moment)!!! A plane with a symmetric airfoil in a vertical climb has an AOA of 0. A plane with a cambered airfoil in a vertical climb actually has a negative AOA.

All the same basic principles apply to models that apply to full scale with a few exceptions. Enormous power and very light wing loading make up for most of the differences. Size does matter because an air molecule feels much bigger next to a .40 size trainer than it does next to a 747. A small vortice will effect a model with more impact than it will a 747. Do a search for Reynolds Number to learn more.

Oh... I also know a lot of dumb doctors (of the MD type) so don't feel I think you know it all

P.S.- I can tell you will perfect authority that a C-130 does not fly at 0 degrees AOA. It averages 2-5 degrees and will go up to 8 degrees for certain types of airdrop. Much more deck angle and it gets fairly sloppy and uncomfortable (unless in a high G maneuver at higher airspeed... I'll see over 10 degrees in that case).

flatlandmike

My Feedback: (17)

i cant believe how much time i wasted reading this entire thread to see what the big deal was about[:@]