Here is a picture of a lightened IMPACT rudder that I snapped at the Nat's.

Then three pictures of George Asteris's latest IMPACT with a stock color scheme. Wish mine were that color.

I can see mine but not as well as his. Maybe I should replace them with these colors?

Eric.

Eric:

You snapped the rudder at the Nats? (or the picture). Is the lightened rudder shown the original composite rudder with holes cut out or a balsa rudder you built? We will be putting one together this fall and I'm looking for all improvements.

Thanks
Mike Wickizer

Ahhh the power of the written word.
I wonder how many people (me included) read that to say He snapped the rudder, not the picture.
I been waitin' on the post showing the broken rudder
Eddie

I did, but I couldn't see where the rudder had snapped in the picture he posted.

Why Hello there. I sense of a Nat's Champion somwhere in the ether :-)

This was just a Picture of the tail od 2 time Masters Champion David Snow's plane. He woudl have the answers.

Mine were foam sheeted with balsa and were about 1.5 oz when done. I junked the originals and fitted a double bevel hinge post and rudder LE..


The photos of the new, easier to see IMPACT come with the owner's infornation that this version is, and I quote, "Way lighter!".

Eric.

P.S. Using two bolts per wing makes a big difference to rigidity etc. and it was SNAPPED as in Photo.... You all got me that time....

Eric,

Did Dave shortened the wings also? The wing tip looks completely different than mine.

Just curiois,

Adrian

Adrian, I heard second hand that Dave had someone make up balsa sheeted wings for his Impact, for the purpose of saving about 4-6oz. He also ran without a spinner, and it looks like he modified the rudder. All, I presume, for the purpose of making 11lbs with his electric Impact.

Edit: I'm also thinking he was running sans wheel pants.

Pretty sure those wings are sheeted foam. Think he said they were based on temptation wings.

Dave's wings are the same airfoil as the Temptation and they have a different sweep on them. The sweep is the same as a Phenom which brings the wing tips forward about an inch. The foam is expertly cut by Mickey Losardo and Jim Hubbard and they are balsa sheeted. I have the exact wing on my Shmorphidite (modified Smaragd) which I'm flying this year. The wing gives the plane amazing stability in the air. It's as steady as a rock. We will more than likely be using this same wing on a different plane next year. It's gotten to the point with all the modifications that the fuse is just a device that holds the wings in place.
Here's a pic of the wing. You can get a better idea of the difference in the sweep from it.
Mike

Mike,

What is the main difference between the stock Smaragd wing and the one that you are currently using, is the stability due to bigger wing area? If you don't mind sharing.

Up to now, I consider my Smaragd Z one of the best airplane I have ever flown. It rolls nice, and the up and down line snaps are the cleanest, it really stops on a dime. I think it has a lot to do with the double tappered small wing.

Adrian

My Impact tail broke off yesterday at a pattern meet. I had installed the rear bulkhead and also had a piece of foam mounted horizontally in the tail from behind the canopy to the rear bulkhead. It broke right at the front edge of the rear bulkhead. The pull pull cables for the rudder and the elevator bellcrank and the seam tape at the top and bottom of the fuse where all that was holding the tail on. My last flight was somewhat bizarre, to say the least, not knowing what had gone wrong.

This is my second Composite-ARF to bite the dust. Last year I bought a Rev Pro and the tail boom broke off right behind the canopy on the maiden flight. Composite-ARF sold me the Impact at a considerably reduced flight with assurances that the problem was fixed. Bullfeathers. The only difference I see is that this one broke off right in front of the tail feathers rather than behind the canopy. I fly intermediate so there are no vilant maneuvers. I've never even tried to snap or spin it. For what it is worth, I did use the stock rudder.

I will never buy anything else from Composite-ARF. Even when they came out with a supposed fix for the Impact, they never made any effort to notify their customers.

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Bill,

Sorry to hear about the model.

Did you happen to weigh the rudder before it was installed into the model and if so what was it?


Peter.

Bill that was a tough one. Hang in there and see if we can at least get you in the air for the remainder of the season. Mike

I was at the contest w/ Bill. Here are the pics of the tail after he landed in round 4

With the increase use of stress skin fuselages in pattern aircraft today we need to change some old habits.
The method of holding the stab as we start and run up the motors is not a good idea.
This puts a great deal of stress on the fuselage. The uneven loads that are applied on the fuselage create stress concentrations on the sides of the fuselage head of the stabs.

Flight loads and starting loads. Make the affected area prone to failure.


Just food for thought from out here in Corn country.

I agree about holding the plane by the stab not being a good idea. I have an OTOP and
I am also changing the way I transport my airplanes so they are supported along the entire
base of the fuselage, not just in the front and rear.

tommy s

Mark we put our plane holders in the front of the plane so the landing gear or front of the wing support it. I beleive that Billy B. had his that way. Bottom line is it seems that the only plane I've seen falling apart in the air is the Composite ARF pattern planes.
They have a great problem with credability that will take years to repair. I personally wouldn't touch one of these planes if they were giving them away for free. Mike

The OTOP has similar construction but they reinforce the back of the fuse with a diagonal former. I have snapped this airplane alot and it so far has shown no signs of this type of problem.

Greg

Mike is correct. I have never restrained my Impact from the stab. Always in front of the landing gear. Furthermore, I never snapped or even spun the model. I didn't take pictures of it, but last night while examining the stock rudder I noticed indents on both side in the front of the rudder that line up with the edges of the back of the fuse. It could be cause by the rudder hinges flexing. I used real Robart hinge pins and not the ones that come with the model. The indents could also be caused by the rudder hitting something while I was carrying it in and out of the basement. I also carry my planes rudder first.

Regardless of all this. I was extremely lucky to be able to successfully land the airplane with no damage to any of the internal components. I am not going to take the chance of repairing it and having a catastrophic failure. Anyone need wings or stabs?

Has anybody witnessed or heard about a failure with the tail on an electric Impact? If there haven't been any it might give some creedance to holding the plane by the tail for run ups causing too much stress on the airframe. If there have been failures with an electric, with all the mods of course, then it's just a poor design materials-wise.

My electric Impact is the best airplane I have ever flown... but having said that I'm getting another couple airplanes going, non-CArf going because I just don't trust it. It will be my last C-Arf.

I asked Dave Snow to elaborate on the Impact that he flew at the Nats. Here is an account that I received from him about the modifications that he did to the plane that he flew to a 1st place in Masters. Mike

"I see there are some questions on RCU about the Impact that I was flying at the NATS. Well here are some of the modifications that the plane has and the equipment used.

The fuse is stock with only one balsa stringer each side of the fuse from the wing trailing edge to stab leading edge. There is a bulkhead at the stab leading edge and the wing trailing edge. The two bulkheads that came with the kit for the landing gear and the landing gear plate where remade with liteply. The carbon gear was also replaced with the ESD carbon gear from Central Hobbies. Since the plane is an electric I did not use any of the bulkheads in front of the gear. The pipe tunnel composite foam plate was used as an air deflector to force the air out of the body just behind the wing tube, very similar to Jason’s setup from last year. The wing, stab and rudder are all foam/balsa parts cut by Mickey Losardo that are based on he Temptation’s airfoils. The stab is one piece and glued into the fuse at 0 degrees. We modified the wing plan form to an equal taper as Kirk Gray did with the Phenom, which I had several years ago that flew well in most wind conditions and I wanted to try the wing plan form again which this plane provided the opportunity. The wing/stab/rudder parts were replaced due to the kit parts being heavy and at least one wing panel having a big twist. The foam/balsa wing panels weigh 14.1 ounces each ready to bolt onto the plane where the kit wing panels out of the shipping box weighed about 15.5 ounces. The plane came out slightly overweight so at the NATS we removed the spinner and wheel pants. Removing the spinner had an additional benefit of more cooling air over the motor and batteries. At the NATS the planed weighed in at 10 pounds 13 ounces when using the Thunder Power 5300 batteries. An 11-year-old Futaba 9ZAP with synthesized receiver and JR 8231 servos on ailerons, elevator and rudder was used for control while the Hacker C50 14XL, APCE 22x12W with the Castle Creations Phoenix 110HV controller was used to power the plane.

I hope this answers some of the questions about the setup."
Dave Snow

I've been flying my electric Impact since October of last year with a NeuMotor 1515/2Y 22x12 APC 10s3p LiPo and Castle 85 without any modifications, and to date I have not had any problems with it.
I usually put about 6, 10 minute flights per week on the plane that consist of rolling circles, knife edge circles, snaps etc.,
Pedro.

Hi Bill,

Really sorry to read about your Impact, seems theres still more work to be done by CARF to fix this continuing problem with this particular model. I also had a very similar experience with my Impact ( see earlier posts in this thread ) and the response from CARF was that it was an end user problem! I as well as others that I know of, told CARF that this area needs severe reinforcement but the reply to me was that the structural design was fine and that "Frankly your self appraised expertism pi*ses me off" was one line from an e-mail received by me from Andreas!! Luckily for me the skin of the airframe was still in-tacked just a crease on one side around 4" in front of the vertical stab former. I have glassed this section with glass and cloth and installed a balsa ladder from the rear anti-rotation pegs of the wings to the fin base former at the rear. Also I have added a 45 degree former keyed into the fin base former rear to the sturn post of the rudder. The rudder leading edge has been removed and replaced with a balsa bevel and I have used 5 Robart hinge pins instead of 4. So far I have flown several snaps with the model at various comps this season without any problems......................Doh, why did I say that! I too wonder if any electric powered Impacts have suffered the same problem? Come on you electron addicts, give us some feedback........................please.

Regards,

Andy.

Thanks Mike for getting David to do a short write up on his Impact. I guess the secret's out now. To be a 2 time national champion, you get an Impact, throw everything away except the fuselage. Rebuild the fuselage, manufacter a set of wings, stab and rudder, and get rid of the wheel pants and spinner to make weight! I admire Dave's preserverance, I would have probabley would have shipped the airplane back. It doesn't give me a warm and fuzzy feeling about buying an Impact.
Greg
'

Hey Gregg I like your simple assesment of the situation.
We pretty much did the identical setup on my Smaragd which we now call the Smorphidite. Based on the formula that he has for the wings and stab we pretty much see the fuse as a device that holds our flying surfaces. Mike