ahicks

My Feedback: (2)

Jim -
>>
I agree completely. Careful 'deviating' (with lots of test flights to monitor progress) is a perfectly acceptable method of trimming an airplane to meet the flyer's needs. That's been my point right from when I first suggested it earlier. Sorry if I've managed to confuse that.


Eric -
I think Jim and I agree first flights should be within the recommended CG range. It's after the first flights, when triming to eliminate/minimize problems, that we've been disagreeing. With that much fuel, that far forward, my only thought is you might experience pretty fair trim changes full vs. empty, and maybe the first few flights could be started with half fuel on board? Go ahead and fill it when you have a little better idea of what to expect regarding everything else, are better equipped to deal with any issues?

Al

redbiscuits

My Feedback: (6)

This is from the GSS manual. Recommended CG is 5.250 from leading edge. Wes is well within the recommended CG.

"This is where your model should balance for the first flights.
Later, you may wish to experiment by shifting the C.G. up to
1" [25 mm] forward or 1" [25 mm] back to change the flying
characteristics. Moving the C.G. forward may improve the
smoothness and stability, but the model will then be less
aerobatic and may require more speed for takeoff and
make it more difficult to slow for landing.Moving the C.G. aft
makes the model more maneuverable, but could also cause
it to become too difficult to control. In any case, start at the
recommended balance point and do not at any time
balance the model outside the specified range."

RC Specialties

You fellows have said it all. I do have one point. With a large than normal tank up front you will be nose heavy when full. Watch your control throws. At slower speeds you will need more throw. Normal control throws may be enough but you never know. I agree with starting with less than full to see how she reacts in the air.

Jim

wesrcfreak

Redbiscuits: I read it also in the manual.
So I think to start with the CG at 5,5511 inch from the leading edge.
Regards Wes.

wesrcfreak

I installed my servo's and I see that my elevator is not going 100% evenly up and down.
I installed the two servo's together with a Y-cable.
Would this be a problem in flight?
Sorry for my english.
Regards Wes.

Super08

My Feedback: (2)

Yes it will cause the plane to roll as you apply elevator.

wesrcfreak

Ok but I don't know how I can fix it.
The pushrods have the same length. Everything is like the manual says.
They still not moving evenly at the end of the movement.
Regards Wes.

Super08

My Feedback: (2)

One of your servos may be dragging and not as fast as the other. Try swapping out the slower one with another in your plane and move it to the throttle or rudder. You will need two matching servos on the elevator for good performance.

wesrcfreak

maybe I was not clear enough.
but the servos are equally fast.
It's just at the end of the movement.
One elevator does not go as far as the other.
Regards Wes.

ahicks

My Feedback: (2)

Wes, maybe he's thinking the travel, but wrote speed?

You might try adjusting the travel mechanicaly? To get more travel out of the one lagging, you could move the attach point on the elevater closer to the surface, or the one that's moving more away?

A lot of radios will let you set dula elev. servos up as a master/slave. Then you could use end point adjustments to match?

wesrcfreak

Ok thanks.
I going to try fix it mechanical on the attach points.
My radio having not dula elev. I having this function only for my ailerons.
Regards Wes.

ahicks

My Feedback: (2)

Sorry Wes, I meant dual elevator (not dula!)! Many radios have the capability, just look to see if you have an aux channel available, and a master/slave setup function...... -Al

Super08

My Feedback: (2)

If your radio cannot do that a matchbox will work for you. They are not that cheap though. Below is a link to the Futaba one. It plugs into one channel on your receiver and lets you run up to 4 servos. Each one can be adjusted for center and travel separately which will solve your problems.

http://www3.towerhobbies.com/cgi-bin...?&I=LXCTS1&P=0

Schummie

Wes,
What radio you have?
You could go connecting the two servo's seperately to the receiver. That way you can ajust the travel of the two servo's seperately. Most radio's have a dual elevator option to mix this. Also if there is a free mix on your radio, this will work. I think the poblem in your configuration (according the manual) is not that the servo's don't match. It's becouse of the fact that the angle of the two rods to the servo's is not the same. And that is becouse one servo is placed reverse to the other. The manufacturer has done this to make it possible to fly this plane also with relative simple radio's. So, if you have a radio with programable mixes, your problem is solved with only a second kong extra servo wire and some programming. I've done the sam in my Sportster.

Regards,

Eric Schumacher, Netherlands.

wesrcfreak

@schummie
My radio is a Graupner MX12 with smc 20 ds scan reciever.
Regards Wes.

Schummie

Wes,

Then it will work. Keep one elevator servo in the elevator channel, and the other in channel 5 or 6. Your radio has 4 programable mixes. Make the elevator channel Master, and the other (Ch5 or 6) Slave. Yoy may have to reverse servo on the slave channel. You can ajust travel seperately on the two channels. That way you can always reach same travel on both servo's. Succes. It is also on page 23 in Englisch in your manual.

Regards,

Eric Schumacher, Netherlands

Schummie

Wes,

A little more to help. For the rest, it's partly in Dutch. Sorry for that. Wes, here is wat you do to get the second servo on channel 5. That way you can keep the 2 airlon dervo's also on seperate channes.

- Vliegtuig met 2 hoogteroer servo's:
We gaan het ongebruikte kanaal 5 gebruiken om de tweede hoogteroerservo mee aan te sturen.
Kanaal 5 wordt normaal gebruikt voor een landingsgestel of andere extra functies. We gaan eerst zorgen dat de normale bediening van kanaal 5 (de switch rechts achterop de zender) niet meer werkt. Dit doe je door in de systeemmodus bij het menu [SWITCH SEL] het volgende in te stellen: GEAR INHIBIT. Nu heeft de rechterswitch geen invloed meer op kanaal 5. Nu ga je in de functiemodus een mixer maken. Dit moet er als volgt uit gaan zien:
[MX1] ELE -> GEA
ON OFFSET 0
100% 100%
SW ALWAYS ON
Nu krijg je op kanaal 5 hetzelfde signaal als op kanaal 3. De kanaalindeling wordt dan als volgt:
1 Gas
2 rolroer rechts
3 hoogteroer 1
4 richtingroer
5 hoogteroer 2
6 rolroer links

Succes.

Regards, Eric Schumacher, Netherlands

wesrcfreak

thanks a lot Eric.
Regards Wes.

Schummie

Engine in place and ready for the engine tests. It is a used OS 160. After replacing the glow plug running perfectly. Used a 18x6 prop. Will put a larger one on . 18x8 or 18x10 becouse engine revs at nearly 11.000 rpm.

Regards,

Eric Schumacher, Netherlands

redbiscuits

My Feedback: (6)

Eric,
I would try going to a larger size, say a 20x6 before I would go up in pitch. Just my thoughts
Red.

ahicks

My Feedback: (2)

I agree, that would be my experience too! Plenty of ground clearance to allow that as well.

Howard

My Feedback: (55)

I am really struggling with which plane to build next a GP Super Stearman or the GP Giant Super Sportster. Both are in boxes and waiting to be built. Today I am leaning toward the GSS. I had planned to use the CA hinges but to add some additional what do you think. I noticed that one gent shortened the position of the propeller hub by 1 inch and wondered if that would have a significant impact on the way the plane flys. This is really a majestic plane and none of the new models are an acceptable substiute IMHO unless GP decides to make a Giant version of the Revolver, maybe then.

Howard

redbiscuits

My Feedback: (6)

Howard,
I don't think you would be disappointed with either one. My suggestion is to build the GSS with the Stearman landing gear and order a new set from Tower for the Stearman.
I wouldn't think that pushing the engine back would be a big issue but I wouldn't take that as good advise.[sm=spinnyeyes.gif] It all depends on what engine you are planning to use I guess. It would have helped out my CG a lot but, I don't fell comfortable changing things like that yet.
Red.

ahicks

My Feedback: (2)

Howard,
If you're looking for a big playful puppy with a fair share of performance, this is it. A great sport plane in the strictest sense - JUST like the others in the Sportster family! It takes to gas engines really well with all kinds of wing area available to support the extra weight. Very confidence inspiring!

Like Red mentions, the engine location on my plane was all about the motor I used. A Quadra 42 is not real well known for being light weight? I didn't really move the motor back so much as I didn't move it forward to meet the plans spec? Doing that would have required shims of some sort between the firewall and the motor. I just couldn't see moving the weight of the motor any further forward than necessary - only to be counterbalanced by even more weight in the back to balance? The move worked out well anyway. The cowl slides back over the firewall about an inch without modification so the relocated position of the spinner is a real non event.

The plane, with the fat Quadra 42 (including spring starter), is just shy of 16.5 lbs all up, and it flys really well at that weight. Actually have a new motor on its way for it. With that (Turnigy 52) I'm hoping to increase the hp from 2.7 or so, to something closer to 4.5, and trim maybe 1.5 lbs from the plane as part of the move. Can't wait to see how that works out.... This was my first gas plane and I just wanted to get it into the air to see what it would do. Now that I know that, we'll change it a little to see what happens.

Regarding the landing gear, with all the messing around with CG I was doing, coupled with some initial setup trouble (including blowing both ailerons off on one flight), then dealing with trying to get it slowed on short final to top all that, I have yet to break the gear mounts inside the wing loose. It's not because they shouldn't have either. I've bent them back over an inch on several occasions - I swear! I used to remove the gear to straighten in a vise when that happened, then reassemble to avoid stressing the blocks. Now, I just carefully pull them back into position without even removing the wing from the plane. (Now watch me break them on the next flight!!). Point being, either I got a good one, or they may be doing something differently regarding those blocks and all the trouble some have reported earlier. FWIW

Regarding the glue in hinges, if you're going to roll the dice and use them after so many have had trouble, make sure you glue the daylights out of them, and then pin them! I would not use the solder on clevises supplied/recommended under any circumstances, for any reason!

Kostas1

Nice engine selection!

I use an OS 160FX too on my Giant SS with an APC 17x10-N.

Try it.
But i don't know rpm,haven't measured it!

When will you maiden to see some more pics and maybe a video?