|
RE: 1/4 scale F9F Panther build
1 Attachment(s)
oops!
|
RE: 1/4 scale F9F Panther build
I wear glasses not contacts, Just saying.
Tim. |
RE: 1/4 scale F9F Panther build
Maybe Mr. fun can borrow your glasses next time he comes out to fly by you. In the mean time I will talk him into flying Futaba again. Real jets fly Futaba. http://www.rcuniverse.com/forum/fb.asp?m=11250612
|
RE: 1/4 scale F9F Panther build
Yeah, but if they used Spectrum or JR they woul have had more than 50 Yards of range, I'm just sayin'........................LOL
|
RE: 1/4 scale F9F Panther build
They obviously needed to drill some tiny holes in the fuse to expose the little futaba antennas for better range.....;)
I want to meet the guy that grabbed this thing by the tail to rotate it every 90 degrees during the range check!! |
RE: 1/4 scale F9F Panther build
1 Attachment(s)
But Terry Jr/ Spectrum makes your contact lens pop out........... Does anyone have a good right angle picture of where the instrument panel ends in relation to where the canopy opens? I think Ziroli shows the instrument panel too far back.
|
RE: 1/4 scale F9F Panther build
1 Attachment(s)
Hi, JoFunk,
Here is a side shot of a Panther to show you where the instrument panel is located: Larry |
RE: 1/4 scale F9F Panther build
1 Attachment(s)
Hi Joe,
coming on well......;)...started appying the silver paints/panels to mine next will be finishing off the canopy frame etc..... all the best Dave |
RE: 1/4 scale F9F Panther build
"But Terry Jr/ Spectrum makes your contact lens pop out"...........
Ha Ha................... But I don't use contacts................LOL |
RE: 1/4 scale F9F Panther build
1 Attachment(s)
Then you may be ok Terry..... Thanks Larry for the image.... Dave the Panther is looking good. Keep us posted...... It looks like the panel with the gun sight comes just short of the opening. I know it must be close because the gun sight says"NO HAND HOLD". I extended my panel back and raised it a bit just to get everything looking close. I can always sand it off if I wind up not liking it. I extended it with some thin cardboard and a few layers of glass to stiffen it up........ Some unfortunate news today. Mr Fun started working on a Foremost and a Viper (Till 4 AM last night). So it looks like his Panther has fallen aside.
|
RE: 1/4 scale F9F Panther build
1 Attachment(s)
A little sanding and trimming with a squirt of Krylon primer to see where we are at and it looks pretty good. A little icing to fill a few spots I couldn't sand out will finish my extension. Something had to be extended because the canopy wouldn't have covered the old opening where the black line is. I leveled the fuse on the crutch and wedged the stab down into the saddle. The plans say the stab should be 0 degrees. I put an incidence meter on the stab expecting something to be out of whack and was pleasantly surprised. Zero, zero that means no elevator trim necessary on the first flight............."Yea Right". The weather is really crummy so I can't paint primer or color. I may need to pull out the Hostetler 172 if I stay motivated.
|
RE: 1/4 scale F9F Panther build
Hi Jofunk,
I'm curently flying a Ziroli Panther with a Jet Cat P-80. It took a lot of nose weight to keep it from climbing on takeoff. I also have about 1/16" down elevator to make it fly level. After I got it to this point, I did a incident reading and found the stab was at 0º but the wing was at 1º positive. Don't forget this plane was designed for Ducted Fan. Nick wanted to get it light on the wheels as quick as possible, so he used 1º positive incident on the wing. Beleive me, if you didn't take that out when you built yours, it will climb out on takeoff..... Larry |
RE: 1/4 scale F9F Panther build
Hi larry,
Wouldn't nose weight be a function of balance? The whole plane sits on the landing gear with a positive AOA at takeoff. What is your take on the washout I cut into the foam cores? While the root may be at + 1 degree the washed out tip is something less. thanks, Joe Felonk |
RE: 1/4 scale F9F Panther build
Hi Joe,
You are correct about the balance. The one thing you have to understand is this, with a positive AOA in the wing, any forward motion on that wing will make it climb. Unless you take that positive AOA out of that wing, or add positive AOA to the stab, to counteract the lift that the wing is making, when the speed gets high enough, the wing will want to change to a more positive AOA. Which means a higher climb rate. Since I already had the repairs made and the airframe painted with deacls on, I had to move the CG forward. To do this, I had to add more weight to the nose. Most of the time I balance my planes with a 15º nose down angle. With this Panther, I had to balance it 25º nose. I don't claim to be a aeronautical engineer, but I do know what happened when I added more noise weight. There is a guy on RCU that goes by the name of rhklenke that enlarged the Ziroli Panther planes to a 80" wingspan I believe, and I was in touch with him about the 1º positive AOA in the wing. When he test flew his, he had to put more weight in the nose. I saw him this year at a Jet Rally on the East cost and he said if I hadn't mentioned to him about the extra weight I needed, he wouldn't have believed it if he didn't see it himself. All I'm saying is this, just be perpaired to add more weight than you thought it would need.... Larry |
RE: 1/4 scale F9F Panther build
John Roth put up some pix. of your hatch rework
|
RE: 1/4 scale F9F Panther build
ORIGINAL: Instructor Hi Joe, You are correct about the balance. The one thing you have to understand is this, with a positive AOA in the wing, any forward motion on that wing will make it climb. Unless you take that positive AOA out of that wing, or add positive AOA to the stab, to counteract the lift that the wing is making, when the speed gets high enough, the wing will want to change to a more positive AOA. Which means a higher climb rate. Since I already had the repairs made and the airframe painted with deacls on, I had to move the CG forward. To do this, I had to add more weight to the nose. Most of the time I balance my planes with a 15º nose down angle. With this Panther, I had to balance it 25º nose. I don't claim to be a aeronautical engineer, but I do know what happened when I added more noise weight. There is a guy on RCU that goes by the name of rhklenke that enlarged the Ziroli Panther planes to a 80'' wingspan I believe, and I was in touch with him about the 1º positive AOA in the wing. When he test flew his, he had to put more weight in the nose. I saw him this year at a Jet Rally on the East cost and he said if I hadn't mentioned to him about the extra weight I needed, he wouldn't have believed it if he didn't see it himself. All I'm saying is this, just be perpaired to add more weight than you thought it would need.... Larry Yep, that's me. My 80" Panther has a *lot* of nose weight to keep from climbing under power. I haven't final painted mine yet and I'm considering whether or not I want to change the angle of incidence of the wings before I do. The one benefit of the extra nose weight is that on landing, it really sticks to the ground... :) Bob |
RE: 1/4 scale F9F Panther build
Hi Bob,
I noticed that when I try to fly inverted, the plane wants to dive toward the ground. It would fly better if you took out the 1º Positive Incidentence in the wing, at least in the inverted flight pattern...... Larry |
RE: 1/4 scale F9F Panther build
Does it climb with power or speed? If it starts to climb immediately with a power increase I would think that it might need the tail pipe angled down a tad rather than shifting CG?? If it is speed replated, then it is a wing/tail/incidence/CG issue.
|
RE: 1/4 scale F9F Panther build
Before I added the extra weight it would maintain a high angle of attack at any given speed. Now you might say that I was tail heavy. But like I said in the above post, I always balance my models 15º nose down, prop or jet. This model had to be balanced 25º nose down to make it fly level using any power range. Now that Bob replied that his enlarged version flew the same way, I would have to say it's in the design. You have to understand that this model was designed for ducted fan, not turbine. Maxium spped on a DF version was 130mph, mine has been clocked at 165mph. What you are asking is, if I reduce the power does it drop it's nose, it would slowly drop it nose. So there was problem with the AOA. Since I had already rebuilt this plane to the point where it was repainted and new decals installed, I wasn't going to tear it apart and change the Incidentence. So the next best thing was to add more nose weight. If someone asked me how the planes flies, I would just have to tell them, "If you build it the way Ziroli says, you will have to add more nose weight to keep it from climbing with anything above 130mph. Unless you take out the 1º positive Incidentce in the wing during the build......
Larry |
RE: 1/4 scale F9F Panther build
1 Attachment(s)
I will take that all into consideration. Does anyone have an opinion about the washout I cut into the foam core?............I needed to open holes on the top of the winglets to access the set screws on the wing plug ins. I should have done it before I installed the intakes. I had to resort to an educated guess and a long pin to probe for the hex head screws. I could see a few of them from inside the plane. The rest I could feel the six flats of the cap head screws and then I checked if the pin was standing straight up. If it wasn't I biased the hole I needed to make in the direction I needed. I only screwed up one hole. A little icing plugged it and I re drilled the hole where it needed to be. I am going to paint the wings with the control surfaces hinged. It will be easier and your eye won't see anything the spray gun doesn't .
|
RE: 1/4 scale F9F Panther build
1 Attachment(s)
Hi Joe,
just to let you know we flew mine as per plan with zero on the tail and wing as per plan, P70...2 ltr's of fuel and it flew fine......no lead in the nose just the batteries.....all3 of them, the turbine and 2 receiver...... made a start on the stencils tonight....will finish the black tomorrow and then make a start on the white yours is looking really great!......once you get the whole airframe in primer....then it comes together.....not far off that now...;) |
RE: 1/4 scale F9F Panther build
I flew my Panther three times yesterday. As I said above, it does have the extra nose weight in it to counter-act the climbing tendency that Larry points out above.
In inverted flight, it requires quite a bit of forward stick to fly level, and it does definitely drop its nose in a turn. However, it lands GREAT! There is no bouncing tendency like has been reported for the Fei Bao Panthers in a recent thread. Also, with full flaps, and full split flaps (I added those to my Panther too), it slows down really nicely and there is plenty of elevator left to flair at quite a slow airspeed. I was considering reducing the wing incidence before I painted the plane, but after a great flying (and landing) session yesterday, I'm reconsidering that... Bob |
RE: 1/4 scale F9F Panther build
Before Bob finished his Panther, I sent him a PM letting him know about the 1º positive incident in the wing. Now I don't know why some Ziroli Panthers require more nose weight than others, but like Bob, I had to add more nose weight to get it to fly level. Now I bought mine already built and converted it from a DF version to turbine. Having two different Panthers built from the same drawing by two different people and they both fly the same, tells me that the design has a problem...
Larry |
RE: 1/4 scale F9F Panther build
Hey scale man the Panther looks great....... Taking out the 1 degree positive would need to be done early in the build. On my plane it would mean tipping FW-1 5/8" LE down or a combination of LE down and TE up to take out the 5/8". That changes the shape of F- 8,9,10,and 11. It would also change the shape of the intake....... Anyone want to discuss washout theory?...... I made a cinderblock and foam saddle to hold my wing vertical while I glued in the Robart hinge points. I will need a ladder to do the elevators and rudders. I used a few pair of disposable gloves because I was tired of picking up control surfaces with glue on my fingers. I sprayed some Contact clear shelf liner with Krylon primer and sprayed it with some blue paint. When cut into squares,,,,,I mean access panels, they can hide the wing set screw holes. I will soon air brush some paint into the hinge lines on the wing to color it in. I will keep my fingers crossed for some good October/November weather to do some major spraying..........In the mean time the Hostetler 172 got more servo pocket work.
|
RE: 1/4 scale F9F Panther build
1 Attachment(s)
Some pix.
|
| All times are GMT -8. The time now is 01:34 PM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.