RE: GP CHRISTEN EAGLE
 

Mine set pretty flush with the incidence set correctly. I did have to reallly play with the top wing incidence though. Make sure you check them with a meter. What a difference a degree one way or the other makes.

RE: GP CHRISTEN EAGLE
 

The only problem I had with the bottom wing was the trailing edge fit was very tight. It is probably similar to your experience but not as bad -- didn't have to adjust dowels, allowed slight dimples on the trailing edge of the wing from tightening the mounting bolts. After mounting/dismounting the wing this problem resolved itself. Like you, since the wing sits flush in the wing saddle I assume incidence is correct and since the top wing is mounted relative to the bottom wing I assume incidence is correct with it.

Since I don't plan on entering this airplane into a EXPERT-level pattern contest I'm really not worried about it -- my normal flight trim will take care of minor irregularities in the airframe.

Of course, since I have yet to get this bird into the air I really don't know yet. I'm having some problems with the Fuji BT-50SA engine and will have to remove the cowl to work it -- actually, I have set it aside while working on other projects. This is my $1700.00 airplane and I'm not in a rush to throw it into the air until I'm 100% confident in the engine -- you DO NOT want to dead stick this airplane.

RE: GP CHRISTEN EAGLE
 

It's amazing how much the Pitts and the Eagle are so similar. I had the same problem with the Pitts wing dowels. The wing sat up in the saddle at the dowels about an inch or so. Like Chuck, I had to grind out the dowel holes to get the wing flush in the saddle. The trailing edge also fits sung, but not a problem. I used a meter to check incidence and all was good. For you guys still working on the wings, watch the alignment of the upper wing to the lower wing when mounting. On my first attempt I was off several degrees which would not have been good. I had to plug and re-tap for the Interplane brackets because of this. I also used a meter to check the alignment and was right on.

hilleyja - I saw your comments about the Fuji 50 BTSA. Whats going on with the engine? I recently saw that Fuji is now coming out with electronic ignition. This should help them a lot. It will certainly take away some weight and make them easier to start, but will probably take away some of the running smoothness as well.

RE: GP CHRISTEN EAGLE
 

This is really my first gas engine so I'm learning. The last time I tried to work this, it took me a while but I eventually got the engine to run. Idle was smooth and transition was pretty good. There was a bit of roughness with transition right out of the gate so I killed the engine and made a slight adjustment to the high-speed needle. I couldn't, to save my life, get that engine to start again. I even backed off the adjustment but was still unable to fire her up. I'm running with the Fuji spring starter so I should be getting pretty good engine startup spark from the magneto.

The exhaust is very black and very wet. The engine is farely new though I did acquire it used. I'm treating it as if it was new and running 25:1 oil with premium gasoline. I'm assuming I flooded her big time and fowled the plug. She is mounted inverted so I'm assuming I could not refire because of the fowled plug. Unfortunately, because of the the way I installed the exhaust deflector, removing the cowl is not easy and I did not provide a hole for access to the plug. I will have to cut the deflector flush with the bottom of the cowl -- just haven't done it yet. My local gas engine guru also wants access to the carb while the engine is running. I don't know how that will help him because the carb adjustments face forward -- doesn't leave much safe room for a screwdriver while running.

RE: GP CHRISTEN EAGLE
 

Roger:

When you measure the wing incidence, what do you use as a 0 angle reference, or how do you know that the fuselage is level? I'm about ready to fly my eagle for the first time next week and I wan't to make sure everything is setup correctly.

Stephen

RE: GP CHRISTEN EAGLE
 

Stephen,

The goal is to have zero incidence between the wing and the horizontal stab.

Make sure the wing fits flush in the wing saddle. Place the incidence meter on the wing and then prop the nose or the tail up until the incidence meter reads zero degrees. You now have a perfectly level wing as it sits mounted in the saddle.

Now mount the horizontal stab. The wing should be level from your previous reference point check of zero incidence. Now set the horizontal stab so you have zero incidence in it, as it compares to the wing. Both should be at zero otherwise you will need elevator trim in flight to offset either positive or negative incidence.

Likewise, a friend of mine has a modified incidence meter that allows checking, I believe the term is the Cant angle, or what I simply call, the left to right alignment angle of the top wing to the bottom wing. [8D] With the plane sitting on it's gear, and the lower wing mounted, I then mount the upper wing to the cabbane strut with both bolts inserted. I used the measurements in the directions to mount the first interplane strut, which for the Pitts was 3 1/4 " from the TE of the aileron to the TE of the lower interplane strut. Then I place the meter vertical, on a level service, level and against the lower wing leading edge at the Interplane strut so that the top of the meter makes contact with the upper wing.. ( Picture a vertical ruler on the floor making contact with the leading edge of both wings to get a better picture) I then slightly twist the upper wing either left or right to get zero degrees variance between the alignment of the upper wing to the lower wing. While holding the wing as still as possible ( need some help here ) use a marker to mark your drill points on the second interplane strut. Check both side at the interplane strut reference points to see that the variance is the same. When completed the alignment should be to within zero to maybe 1/2 degree, left to right of center.

I hope this made sense and has helped.

RE: GP CHRISTEN EAGLE
 

Thanks Roger,
Thats exactly what the wing was doing, scared me for a second. I glued the belly pan on and cut the height down. Good thing it only takes a scrap of white monokote to cover it.

Chuck

RE: GP CHRISTEN EAGLE
 

Hey guys,

I had the similar problem with the lower wing![:@] I would tighten it down and the covering would wrinkle. I did the same with the dowels,but what I had to do is put another piece of wood to keep the dowel in the new place or the front of the wing would rock up and down in the saddle..
I knew I should of paid attension when mounting the stab.when I set the wings at the correct incidence the stab was off quite a bit. Need lots of down trim to keep it level!! All I can say is I'm not cutting the stab to fix it,I'll just live with it...
I'm not sure if I adj. the wing or the engine incedence if it will cure it without having another trim problem.. What do you guys think?
Later,
frank

RE: GP CHRISTEN EAGLE
 

Frank, if it were my airplane and I had already flown it without any problems other than having to a make a few minor trim adjustments I would leave it alone.

RE: GP CHRISTEN EAGLE
 

Roger:

I followed what you said about using the bottom wing against the saddle as your reference zero angle and the horiz. stab should also be zero. from what you said about setting up the top wing, the leading edge of both the top and bottom wings should be at the exact same point at the location of the interplane struts. Couldn't I just check the incidence of the top wing at both interplane struts, and if so what should the top wing incidence be?

Thanks
Stephen

RE: GP CHRISTEN EAGLE
 

Stephen , the incidence for both the top and bottom wings are checked in the same manner. You should, have zero incidence between the top, top wing, bottom wing and elevator. I began with the bottom in the wing saddle and then with the fuse propped up to maintain zero incidence on the bottom wing. I then checked the top wing and without changing anything it too should also read zero.

What I was referencing to regarding the top and bottom wing alignment was in reference to how the top wing aligns to the bottom wing, if you were looking down from the top of the wing, and then checked the alignment left to right as the top wing aligns with the bottom wing. This is done in the process of mounting the interplane struts which if not checked will most certainly be off.

Does this make better sense or is it still confusing?

RE: GP CHRISTEN EAGLE
 

I hate to disagree with you but when I set the incidence on my Eagle, I e-mailed Great Planes Product Support and asked for the incidence settings for both the top and bottom wing. I can't remember exactly, and I've tried looking through my old files but can't seem to find their response, but there's a 1 1/2 (don't quote me exactly on this) degree incidence difference between the top wing and the bottom wing. I would suggest contacting them and get the EXACT wing incidence before setting anything up...

RE: GP CHRISTEN EAGLE
 

If ya go to the tower hobbies site and look up the Christen Eagle. Then scroll down and it tells ya what the settings are.. the CG,throws ect.
Later,
Frank

RE: GP CHRISTEN EAGLE
 

John, no problem on this end and glad you referenced the difference in the Eagle. I have always tried to make sure everyone understands that I have the G.P. Pitts which is similar, but not the exact same airplane. On the Pitts the incidence for the top, bottom wings and the Horizontal stab are all at zero incidence.

RE: GP CHRISTEN EAGLE
 

I just got my eagle and am concidering a g-62. Could you let me know how it has worked out for you? Thanks, Andy

RE: Elevator/Rudder Servo Arms
 

Maidened mine yesterday. Good results. I have a Saito 270 and pull-pull rudder. I didn't have to add any weight except for lateral balance and that wasn't much. I am flying with a 20/8 prop and it felt underpowered. I am going to try a few props and see what I get. It is flying nicely. Fully flying on the wing. It did drop a wing tip on the first landing when it got slow but it was very close to the ground so everything was ok. The next landing was a greaser and it looks good coming in like that. I did experience the landing bounce but I am on grass and it wasn't bad. With more practice I'll be ok. I did however manage to loose the tailwheel. I flew anyhow 'cause the tail comes up so fast its isn't really an issue. I didn't use springs on the tailwheel since my set up is different and it turns great on the rudder. I needed quite a bit of right rudder on take off. more than I 've ever used before. It also fits in my 87 Volvo wagon in one piece which is a BIG PLUS!!! Gonna add smoke once I get some more power out of the motor. I still have some nit-picky complaints about the kit but after flying you feel better about the things that pissed you off while building.

RE: Elevator/Rudder Servo Arms
 

The 270 fit without cutting out the top of the cowl? I dry mounted mine and it looked like the top of the cowl would have to be cut for the carb intakes... So I mounted a DA50 and it hauls butt!!



Wolfeman,
I heard of guys using a G62. I think the weight my be an issue.. I used the DA 50 because the power to weight of it...But there are guys that have been flying the Pitts for years on G62s and love them..
Later,
Frank

RE: Elevator/Rudder Servo Arms
 

xtraflyer,
It fits like a dream! The needles point down and the chokes pull from the bottom, there is even room for them to slide up and down inside the cowl. No extra cutting of the cowl was required except two small holes in the bottom for the choke rods.

Now I sure don't have the DA 50 power so I'm gonna try some different propsI hope it helps. I'm used to flying my DP Ultimate which flys a lot more nimbly. I have to get used to the weight of the GP and the speedier landing characteristics. I do like the difference and the change. Change is good!

RE: Elevator/Rudder Servo Arms
 

RC Jones,
I must have a really old version. My needles come out from the sides as do my chokes. Does yours have a radial mount that also acts as the engine backplate?
A friend of mine had one in his weeks special. Not sure what prop 20x10 I think. It flew it well though.
Good Luck with it. Love the looks of mine but I'm also used to my old DP 330L that landid like a butterfly!!!!
Frank

RE: Elevator/Rudder Servo Arms
 

I don't know about the backplate thing....Can't you rotate the carbs? Is your friend available for questioning? Bring him in so we can debrief him. Inquiring minds need to know. We need the facts!

RE: Elevator/Rudder Servo Arms
 

AHA!!!
It only has one carb and its in the middle of the intakes.. the intakes come from the top of the cyl.heads curve up and go into the carb. I will have to get some pics. later so you can see and we can resolve this....
frank

RE: Elevator/Rudder Servo Arms
 

I've heard of the 270 with one carb but never seen one. Do you have any numbers on yours? I want to know if this is as good as it gets with this motor or should I be looking for more?

RE: Elevator/Rudder Servo Arms
 

On the destructions they say
7,200 on a dynathrust 20x8, 8.5 kgs static thrust.
8,100 20x8,top flight prop,9.0 kgs. static thrust.
7,300,20x10, Zinger 8.5 kgs.static thrust.
These are all approx. Sounds like the Top flight is the winner with almost 20lbs. of thrust
Practical rpm,1500 - 8000
Don't know if this helps but good luck..
Frank

RE: GP CHRISTEN EAGLE
 

Ulf:

I did the same as you to mount my DA50. PITA to get the bolts in, but works out nice in the end.

Did you have to cutt the muffler or the cowl to get things to fit?

I'm about there now and wrestling with this issue.


Thanks,
Lee Snover

RE: GP CHRISTEN EAGLE
 

From people who have built and are currently flying the C Eagle I need advice on: gas engine: BME, DA, Brisson or other and why, servos , battery and any other equip for a safe flying Thanks