Half-A-Hec

Howdy All,


The weather here in Omaha finally got better. So I decided to take the Re-V-Amped out for its maiden flight. Upon arriving to the field the weather conditions were Sunny, with wind at 13 MPH![X(] I decided that I would give it a go anyways. Besides the plane doesn't know wind only the pilot right? So I plugged in the batt and set my timer for 5-1/2 minutes. I checked all the control surfaces and added two clicks of up trim for good measure. I did this cuz I thought that the plane may be a tick nose heavy. I noticed the sun was upwind![:@] Dang I hate flying into the sun on take off. So I gave her about 2/3 throttle and let her go! BTW, I had to hand launch at this field. She went vertically straight up about 200 feet and the wind carried her down wind of me![X(]. The whole time the nose was pointed straight up! Whoh Nelly! I cut the power to about 1/3 and made one big circle around the field and brought her in safely[8D]. Whew my heart was pounding and my hands were shaking. I rechecked the CG and it was correct and ended up removing the 2 clicks of up trim and actually added 2 clicks of down trim. The elevator probably has 1-2 degrees of down in it now. So back I go to the middle of the field, facing the sun[:'(], and let her rip again. This time all was well! She penetrated the 13 MPH wind with no prob. I banked left and let her get down wind about 500 feet and brought her back up wind of me. No trim required on the aileron and rudder. Probably need trim of some sort but will wait for a much calmer day. I reduced the throttle to about 2/3 and now felt comfortable. Ok lets try a roll to the right. I got her pointed in the wind and added right aileron. WOW. I swear it did 2 rolls in about 1-1/2 seconds. I had my aileron dual rates set to 50% and was flying on the low rates. So I brought her around for another roll attempt into the wind. Same thing! Smooth fast roll with no loss of elevation. I wonder why this plane rolls so much easier than the LLS II since it has the same wing? In fact less aileron input is required to roll this little bird. Hmm. I was going to set up for a loop next but my timer said 1 min left. Oh oh better line her up for landing. So I did and cut throttle to 1/4 and landed her safely in the grass. Whew. That was enough for me. Tomorrow we are supposed to be in the mid 50's with 5-8 MPH winds so guess where I'll be! I will try and get some video for you guys. Bipe get ready for some more little movies.



Hec

flybug

Great report there Hec!

D Bronk

Keep it away from, PUPPY-PUPPY.,at least till the videos are done

Bipe Flyer

Glad to hear it went well! Send me the movies anytime.

Half-A-Hec

Howdy All,

What a great week! Texas beat USC, my Re-Vamped is flying awesome. The planets must be lined up or something. I got 7 flights in today and what I blast I had. My wife managed to take 6 little 15 sec movies before the camera ran out of juice[:'(]. I have sent them to Bipe for another one of his award winning mini movies! Hey Dbronk, remember when you said to keep the plane away from my Dawg? You will like the movies cuz one of them show my Dawg running after the plane after take off. That dang dawg runs full speed under the plane during the whole flight. This plane will loop from level flight, roll, snap roll, fly inverted. Man it flies great. I flew it for my neighbor who is into 40 size stuff and he loved it.


Here is pic at the field.

Hec

propbuster

My Feedback: (1)

Congrats on a successful maiden and a great flying and looking plane! [8D]

combatpigg

My Feedback: (3)

Nice going there, HEC! You got me wondering about the faster rolls, maybe your relative airspeed was greater than you have ever experienced since you were going into a stiff breeze? The small amount of elevator trim to fly level happens from time to time to the best of us, you could try shimming the L.E. of the wing down by a tiny amount just to see if that is the difference, otherwise just have fun with it!

Bipe Flyer

It really looks like you've got a winner there, Hec! It flies really nice.

Here's the video.
[link=http://www.zippyvideos.com/9817425663087686/revamped/]Re-V-Amped[/link]

Half-A-Hec

CP,

If ya look at the pic of the plane sitting on my field box notice the amount of down trim required for level flight. Is this alot? I had zero down thrust on the motor. Maybe I should of had a couple degrees of down thrust? Hmm.


Hec

Bipe Flyer

Hec,

The down trim on the elevator has to do with the h-stab incidence relative to the wing. If the motor had too much up thrust the plane would climb at full power and dive at low power.

Half-A-Hec

Bipe,

Thanks for the awesome video. You do awesome work! I tried to make the H Stab parallel with the wing but it appears to be off a degree or to. Can you tell from the pic?

Hec

Bipe Flyer

Your stab may very well be parallel with the wing, but apparently it needs to be a degree or so positive, or the wing negative. It doesn't matter, that's what the trim is for.

skaliwag

My Feedback: (1)

What does it want to do when you power off?

Half-A-Hec

Skaliwag,

Funny you should ask that. On the last flight of the day I got it way up there and cut the throttle. It wasn't a glider by any stretch of the imagination but I had control of it though. I guess if I had to, I could dead stick it in OK. It flies a lot better if the speed is kept up. I did notice that if it slows down to much the controls get pretty mushy. I land it with the throttle around 1/4 throttle. I will say this, it has a glide rate a lot better than a Littlest Stick. But then again what has a worse glide rate than that?

Hec

combatpigg

My Feedback: (3)

Yes, a little bit of down thrust can help, but that is a speed dependent fix, or better said, thrust dependent fix. It is better to find the aerodynamic equalibrium before resorting to engine thrust angle fixes. That is alot of thrust to be mounted above your tiny wing, on your tiny plane, so it should have a natural [but slight] pitch down tendency even set at zero-zero. The lifting airfoil of your wing might need to be set more negative, I'm guessing. If you're just a couple of clicks off, that's not much to sweat, I'd probably just adjust the elevator push rod length so the XMITTER trim is in the center and call it good.

Half-A-Hec

CP,

Yeah that is what I will probably end up doing. I did notice that when I was at full throttle the plane needed the down trim but at 1/2 throttle, which is where it flew 80% of the time nuetral was right on. At full throttle she will climb climb climb! Inverted flight only required a touch of down elevator to keep the nose up. I managed to pull a knife edge for about 5 sec then she started getting away from me. I pointed it into the wind, pulled up on the nose at about 30 deg angle, rolled it right on its side and kicked in full left rudder. I couldn't believe it was doing it.[8D] BTW my neighbor Ralph was calling out the control inputs for the knife edge. He is better at aerobatics than me.


Hec

combatpigg

My Feedback: (3)

That is why high lift airfoils are a pain when used with variable speed models, the pitch trim issue. Our planes don't need so much lift to be successful, unless the wing loading is too high for gracefull landings

Put yourself through the mental gymnastics of knife edge every chance you can, it's going to double your ability to be the master in charge of what your plane is doing out there[>:]!!.

Half-A-Hec

CP,

I am quickly learning this. As you know this wing was originally intended for my LLS. The LLS was supposed to be an improvement on the LS. The LS glides like a "Greased Man hole cover". So in designing the LLS I designed a higer lift wing thinking that more lift would be just the ticket to better flight performance. I should start tinkering with more laminar airfoil designs. I have a library of NASA, EPPLER, SELIG, Clarke etc.. What airfoils should I be looking at with this low wing design? Any ideas on this guys?



Hec

combatpigg

My Feedback: (3)

You don't have to get too scientific, HEC. If you take a flat bottom airfoil, and give it a fully rounded and symetrical LE from about the 1/4 chord line forward, you will essentially have a wing that is pretty inert when the model changes speed. The best solution to your design criteria would have been to bump up the wing area and go with a semi symetric airfoil. It is handy to have the bottom of the ribs flat so you can build right on the table, and you won't see any difference at the speeds we fly at vs a compufoil super deluxe wind tunnel job. I like high lift airfoils in my 1/2A combat planes, they are single speed and the extra lift keeps the dog fighting tighter and the planes recover faster from upsets, easier to mass produce, too.

Half-A-Hec

CP,

Pic 1 is the airfoil used. It is semi-symetrical. Pic 2 shows both the original airfoil (TOP) and your modified version (Bottom) BTW, the spar locations are right at 25% of the wing chord. What do you think?

combatpigg

My Feedback: (3)

They are THICK! You're going to end up with a plane that glides steep, but if the plane is light enough, that can be very cool! Should be a very fun plane, once you get the pitch trim issue settled, it will be a compromise solution, just get it trimmed for where you do most of your flying. I would trim it for full speed, and then use thumb pressure on the stick for lower speeds. I feel it is OK to fly with down trim, landings are easier to grease in, and inverted flight becomes more hands off. I don't see a whole hell of alot of difference between those 3 airfoils, the proof would be how they work on your plane

build light

The thickness of the wing is also an issue with glide. Basically the more frontal area you have, the more draggy the plane is. It sounds very draggy. By that I mean that with a power off mode the airspeed drops suddenly. Here is where the glide will suffer.

The more weight a plane has with a given wing area ( Wing loading) the higher the airspeed must be to fly.
Could be your plane could use a diet (in the weight dept.), some more wing area so that you don't need as much speed to keep it aloft, or your plane needs to go on a diet ( in the frontal area dept.)

With frontal area, streamlining the nose with a lightweight pointy cowl would help some, thinning the airfoil would help some too.

Given that You use the same wing on your LLS and do not have the same problem. I would look seriously at the ready to fly weight (without fuel) and compare the 2. should they be very close in overall weight. the problem is most certainly drag.

Half-A-Hec

Actually guys there isn't really too serious a problem. The video shows the speed of the plane at roughly 2/3 throttle. I can throttle it down to just under a half and still hold level flight. All in all the plane flies great and the only observation that I had that warranted a question was the need for a little down trim. Build Lite you will see this little bugger fly next Sat. If the weather holds up. I think the performance will speak for itself. We will see.



Hec

build light

Too bad the we couldn't have yesterdays weather. it was awesome for this time of the year. 7day forcast claims that this comming sat doesn.t look bad at all. with temps in mid 40s.

Half-A-Hec

Build Light,


What are thinking of bringing out next Sat? The only thing I have that is airworthy is my Re-V-Amped. Lots of stuff on the fire but only one ready for action.


Hec