Doctorgo,are we the only ones that picked up this wing incidence problem?Has anybody else checked there Pitts with an incidence meter(what are your readings).I treid to adjust mine today,(loosened the cabane and interplane strut screws)I had to drop the trailing edge of the lower wing approx 1/8 to 3/16 to get the incidenceat 0 degrees. Now this opens up another can of worms,as now the Belly pan is sticking out below the fuselage,and I have a gap at the rear of the interplane struts.The Stab incidence is preset by the slot in the fuse(you assume its right)The lower wing incidence is preset by the wing saddle in the fuse,that the wing fits into(you assume its right).The top wing is located by the two cabane mounting points (not much adjustment there,you assume its right).I sure wish i would have mocked up the stab and wing assemblies before epoxing everything(including belly pan)Might have been alot easier to correct this problem.I made all of my measurements close to the fuse,this is not a warped wing problem.This is absolute frustration,and takes away from the smiles i had earlier today after receiving my new BME 50.
Maybe I shouldnt have checked the incidence,but surely it will affect the performance.

Terry

Double check your lower wing for twist!! I have a 1/16 shim at the trailing edge of the lower wing to get it to 0 deg. Last night I checked the incidence out toward the ail. it was a neg.1 on both sides so twisted the wing and applied the heat gun, now I'm showing 0 across the whole wing. My top wing has 1/8 shims under all the T.E. brackets to get the top wing to 0 deg. I also had to reposition the cabanes because my top wing was like a teeter totter when attached to the cabane. I also had to reposition the fuselage holes for the lower wing dowels so that the wing would fit into the saddle correctly.

Steve

Thanks for the info Steve,Ill double check my lower wing for twist,and go from there.

Terry

Checked my angles today; based upon the assumption the stab is at zero, and it appears to be so, the top wing is near zero with one side at a minimal twist in one direction and the other side a minimal twist in the other direction, probably due to the wing struts. I can easily take care of that. The bottom wing is about two and a half degrees negative!! The front of the wing must be raised about .60" to reach the zero angle. I suspect the wing dowel holes were not off location after all and didn't need to be elongated...it's the saddle that needed the alteration. This is ARF #36 for me and of all those before it, no matter how badly they had been, this is the first one that needed a wing angle correction. As you say, the belly pan will need extensive re-work and the struts and associated screw holes will also need alteration. I noticed Tower Hobbies no longer lists this model on their web site. Hmmmmm.
While I'm at it, I'll check the engine vertical thrust angle and its alignment to the stab. That should be interesting, considering...
Regards,
DrGO

I also have had problems with the GP Pitts. I was running an FPE 3.2 in mine and my firewall pulled off also and I was Pi$$ed because the engine landed on the runway and did some damage to it.. When I returned home from the field I sent an E-MAIL to GP. That was more than 2 weeks ago and as of today they have not even bothered to send me an answer. But being fair I will tell you that it flies like a bird and I have no problems with it other than it flys apart. Ken....The "BALSA BANDIT"

Wow 2.5 degrees negative,thats really BAD!I rechecked mine carefully and I am certain the lower wing saddle is the culprit just as youve indicated Doctorgo.Mine is 1 degree negative which is 3/16 gap at the trailing edge.My fix is to make two formers from 1\8 ply that are the shape of the existing formers.I will then split the difference(half of 3/16)raising the leading edge 3/32 and lowering the trailing edge 3 /32. I will then glue my new former to the existing former at the correct measurements.Then sand original former to meet new former at the front,and add balsa to take up space at the trailing edge.Fold covering back over and iron.Once I am done this I will deal with the interplane struts.Right now I need to get busy,Hope this helps anyone with this problem.I am positive there is some of these kits flying with improper incidence,Not my idea of what you should have to do with a brand new ARF,But the sooner I fix it the sooner Ill be Flying. Ill keep you posted
Terry

Greetings.
Zero incidence achieved tonite! Described in detail in a new post.

Regards,

DrGO

Im wondering how everyone elses plane rolls. Mine is not rolling as fast as full scale, maybe less then 1/2 the speed with full rates. Certainly does not roll like the little Kyosho that I had which rolls like a drill.

Input please!

Big planes are not supposed to drill the sky. Try *****g out your throws or use rudder to speed it up a little. If you are trying to snap it. Go into a snap like you usually would and as it goes in to a snap neutralize the elev. this will decrease the drag on the tail and in should speed up a little.

I beg the differ ... I have about 10 hours in a Pitts aerobatic instruction. It rolls .... it rolls fast. Real fast.

I will try with lil rudder which i need to use a lil elevator.

Also my Dave Patrick will roll so fast ... it becomes a blur.

THANKS!

I started on my second Pitts, after crashing the first one :stupid: Last night. I ordered a DA 50 for Pitts II The engine in Pitts I was damaged beyond repair. Flywheel hole expanded on the tapered shaft beyond the set point. Bent the shaft and the ATM device was bent. Thought about replacing with electronic ignition, but after learning the shaft was bent decided it's time for a new engine. Arrgh. Expensive mistake.

Now heres a twist on the firewall reinforcement concept. I had pinned the firewall and fiberglassed it as a result of all those who had experienced the firewall coming loose due to power and vibration from gas engines. Ok, great idea. After the crash I noticed that while the airplane had taken a terrible beating the firewall didn't budge, but the engine was a total loss as well as the airplane. So, how much reinforcement is too much? Now I wish the firewall had come loose on impact which might have saved the engine. Just a thought. I guess the best idea is to reinforce the firewall and then don't crash the airplane. I think the lesson learned on this idea is there is a trade off in reinforcing the firewall. It will hold, but in a crash the engine is likely to receive damage. Who knows?

The firewall on Pitts II was terrible. Gaps between the stingers and the balsa. Arrgh........ Nothing epoxy and tristock can't fix. I removed the thin flimsy tristock around the mounting box and added hardwood tristock with epoxy as before. Drilled and pinned. Will add fiberglass when I get off the road.

The distance from the engine mount to the prop washer is 6 3/8" per DA, so the cowl clearance should not be a concern as I had with the Fuji 50 and the prop shaft extender. Purchased a stock muffler with smoke taps and two Menz 22X8 props. Total cost 677.00. Yep, expensive lesson............. Can't wait to get the engine in. I have heard so many good things about it.

Pictures will follow as I go, if interested. Wish me luck on the second attempt. I will keep an eye on the incidence concerns I have read about on this thread.

Will be flying my PITTS at Rantoul August 23 and 24.
Come up at we can fly together and we can see if my roll rate is faster then yours.

Rantoul

I think I have my ailerons maxed out on high rates.

Come up and fly.

I know there might at least be three PITTS up there.

RORO

Hey RORO:
How's the pitts flying?? I think I have a sale for mine, had all the fun I want with it & I am ready to move on to bigger & better projects. After about 50+ flights it seem to be running stronger with each flight, I really hate to sale it but I feel the need for bigger & higher powered planes.
Later
Gil

PITTS is going pretty good. Been taking it to a lot of fly ins, flying off of concrete, pants are surfering a little.

About 100 flights or so.

It has been fun to push the sticks all around and see what happens.

Here is a pic from the St Charles Festival of Giants in July.

Know the feeling about going bigger, trying to keep the bipe and go bigger too, but might have to sell her.

Thinking of asking around $1000 w/o RX

What about yours?

I have one of these on order now and I have been reading all the horror stores about wings coming off firewalls coming apart and I am getting nervous to say the least. Some of these threads were written in 2002 so does this mean that maybe great planes have made the corrections?
I sure hope I didn't make a mistake purchasing this plane.

Les

RORO:
I am selling mine for $1200 but I might be trading for a 1/4 scale cap & saito 180 new in box + $800. Listed I think they have corrected most of the issues with the pitts but if you are going to power it like RORO & myself you definately want to beef it up. I pulled the firewall loose with the G-62 when I put the mejzlik 22z12 prop on it. RORO, I know what you mean when you talk about the wheel pants, mine are tore up pretty bad flyinmg off of grass, I bought a new set, they sell for $22 @ tower, I also put a set of dubro lite 4" wheels & it does a lot better in the grass.

Gil

I think the new PITTS have all the issues taken care of, BUT I would still pin the fiewall, no matter what size of engine.

Have seen PITTS fly with Saito 300's, MOKI 2.10's, etc...as far as I am concerned I like mine with the G62, other have been impressed too of the power and up lines.

I love to do full throttle snaps, she winds up pretty good, do as many as I can until she starts to tumble down and then into a flat spin........

Gil & RORO
Thanks for the information I am feeling better now.
I have a ZDZ 60 to mount on it so I sure will be taking care in beefing up the firewall, and what ever needs strengthening. I just hope this engine is not too big for it. Sounds like it should be a fun flying plane once a person is comfortable flying it.

Les

Listed:
It should be awesome with the zdz60 & you will definately need to pin the firewall & glassing it will help also. I think you will really like this combo.

Gil

Flew my Pitts today for first time. In a word......GREAT!

I built the updated version and beefed up items here and there as per these forums and common sense. No Guy wires yet, going to make them from fishing line and use nylon clevises to prevent radio interfering vibration.

The airplane still came in light with a Moki 2.10. The Moki mounted on the factory supplied mounts perfectly without needing to use my radial mount. Cowling fit was perfect as well with only minimal cutting required. Airplane uses all HT Metal Gear servos except 3004 on throttle. I moved the throttle servo inside the fuse and I balanced it right on the money without adding weight(shifted the battery forward). Airplane is set up using (4) aileron servos.

With a 22 x 10 prop it will fly vertical out of my hand! No crazy tendancies at slow speeds and stalls are graceful and straight ahead without tipping. Flying field sized loops are no problem, the airplane will knifedge till the cows come home(read where some couldn't get knife edge), roll rate is very good, probably quicker than scale, and vertical climb...well its unlimited, at least for the depth of my 20/10 vision.

What else can I tell you folks. I'm just lucky to be able to own and fly one of these beautiful airplanes.

Tom

P.S. The Moki engine on this airplane took forever to break in on a WM Extra 300s...thanks for your help with my questions about break in on another forum of this site. It runs perfectly now and does so on Zero percent nitro fuel....that was the secret for this hot florida weather.

skyking

How much did it weigh? Did you measure the thrust?

Andrew,

My scale is not the most accurate, but it weighed in at around 14.5 lbs.

As for thrust, I don't know how to measure it without alot of work(I have read about the tying of fishing line behind the airplane at different ratings until it wouldn't snap and so forth). If there is an easy method, I would love to know how much thrust it is making. Sorry, but I don't own a fish scale.....yet.

Thanks,

Tom

Hook you some 50 pound line to the back of your plane & tie it to your fish scale. tie the fish scale to a post, start engine & open up throttle. The scale will show how much thrust the engine is pulling.

Gil

In assembling the new Pitts this will be my first time with electronic ignition. 2nd gas project.

I will be using 4 servo aileron configuration with two Y harnesses. - 2 channels. Elevators using one channel each - 2 channels, rudder, throttle, main battery 1700 mah and smoke system battery 1100 mah- 4 channels. Total 8 channels used. Electronic ignition - 1100 mah battery. using 7 Futaba 9405 metal gear 80 oz. servos and one 9202 for the throttle.

A few questions - Haven't gotten the DA 50 in yet, but from what I understand there is no connection to the RX. It's a completely separate isolated system and to be mounted well away from the RX.

I am using three batteries ( ignition 1100 mah, servos 1700 mah and smoke 1100 mah) and want to back up the main servo battery with a back-up battery and switch system as well. How do you do this when all eight channels are taken?

Is there a battery box to slave two batteries together while not draining power from the back up battery unless the power in the main drops, or the main switch fails? If there is, what do you guys use as a quality back-up system? Your opinion on how I am planning on setting up the Pitts II are welcomed. This would have four batteries after adding a back up for the servos. Make sense? Is there a better way? Weight concerns? Is a back up battery overkill? Would really appreciate your thoughts and help on this?

On your backup battery/switch use a y-harness & connect into any channel of your reciever, It dosen't have to be an empty slot it can be one where a servo is plugged, just unplug servo & plug in y-harness, plug backup battery switch into one leg & servo in other.

Gil