Davros

My Feedback: (1)

Well guys, after reading numerous posts on this site regarding the DP 330L, I have experienced it first hand. Yesterday was the first flight with my DP 330L, BME50,4721's all around. After reading the posts regarding flutter, I opted to install Klett 1/4 scale pinned hinges, and went with 4-40 aileron hardware hooked up to a 4721 (130oz) servo. I also sealed the hinge gap. There was absolutely NO play in the control linkage (ball links). Takeoff was non-eventful, climbed out and started a few low speed (1/2 throttle) passes to trim her out. After about 3 minutes, I am coming across the field rather slowly, and BAM!!!! you can see BOTH wings going crazy with that horrible SOUND!! pull off throttle, continue forward, but guess what, BOTH ailerons are history!!! she rock back and forth, I try to throttle up a bit and keep her alive but with BOTH ailerons , she rocks and rolls and down she goes!! Goodnight!!! Again, I was NO WHERE near high speed and she failed!! There is a definite problem with the design, why the heck do you need such LARGE ailerons?? they are just about useless in 3D anyway... I have been building and flying RC aircraft for 17 years now, and that is my first FLUTTER ever!!! With the above steps I took, this should not have happened period!! I will be talking with Mr. Patrick regarding this issue.

otisflies

Not good....I am a week away from completing my 330 with ZDZ40 and 4721's.

I'm thinking I'll go ahead and add that extra servo in each wing.

Makes me a bit on the nervous side.

What prop were you running?

Davros

My Feedback: (1)

That may be the way to go...My problem with that is why is that not designed in at the factory?? This is an ARF guys, if you want to do a lot of work on a aircraft, buy a kit!! Well the BME seemed to big it thru ok, Lost $100 in carbon fiber (Mez 22X10 and Carbon fiber landing gear)... Bottom line is I think those ailerons are WAY too big!!! They are larger then most 1/3 scale 330 ailerons!!

otisflies

I would agree they are a bit big. I think the problem is that they are big and that they are built up instead of solid. I think what is happening to most people is that the ailerons are flexing out near the wingtips and this is where the flutter starts. So no matter what hardware and servos you use the flutter still happens. The solution is to keep the speed down with a low pitch prop like a 22x8 and to install the extra servos to keep the ailerons stiff out near the wingtips. The people I have talked to who have done this have not had problems

Bottom line is the plane was designed to be flown slow with a smaller engine so I guess we are really pushing things with the gas engines.

BTW I am sorry about your loss. Losing a plane is bad enough but when it happens on the first flight and due to something like flutter its even worse.

Wish me luck!

Davros

My Feedback: (1)

Yes, but it should be setup for 2 aileron servos then period!! I never flew the plane fast during that flight, the motor was very rich to boot... a OS 1.60 or Saito 1.80 would definately pull the plane WAY faster then I was flying...Bottom line is POOR design..Now I know there are a bunch of them flying out there with no problems, and that is great! but I also hear allot about what happened to me...

bpryor

My Feedback: (45)

First, I'm very sorry for the loss of your plane Davros....but I do not agree this plane is flawed in it's design. I flew mine without any problems, and so have most other people. The flutter problems are in the minority of planes flying and should not be blown out of proportion. This is not to say there isn't a problem, I think there is, not with the design, but with the recommended setup. The first thing I think is wrong is the recommended servo size and type. I believe a servo of 130 in oz should be fine, but it should be a metal-geared servo, though I would recommend going with a 150 in oz or greater(JR 8411, Hitec 5945, etc). I ran 200 in oz Airtronics servos. You do not need two servos per aileron on this plane if you run a strong single servo.

The second, and most important thing that is wrong in the setup is the recommended servo arm length for the aileron servos. In my opinion this is where the flutter problems are stemming from. If the recommended one inch servo arms are used and then the linkage on the aileron horn is shortened to get the full 3D throws, you have a ratio created that creates a mechanical advantage that will over power even a 130 oz in servo if the dynamics for flutter are encountered. If you want to set you plane up for full 3D throws, which I assume most people want to, you need to go to 1.5" servo arms which will allow 3D throws while keeping the length on the aileron control horn long enough to keep the mechanical advantage in a safe zone.

BTW, the ailerons being large is not the problem, it certainly exacerbates the problem, but using the setup as recommended above will allow the full use of the large ailerons for 3D and still have a flutter-free plane.

Davros

My Feedback: (1)

I had the aileron setup at maximum mechanical advantage, I was not even setup for MAX 3d throws, as I really don't see the need for crazy aileron throws for most 3D maneuvers. There is just no way this should have happened at the speed the plane was flying. I am VERY airspeed aware in my flying and this was the trim/get to know the ship flight. The bottom line is if you are going to produce am ARF aircraft with these mods, it should be setup for it. What I had on it should have been plenty! I don't think 20 more oz's of torque would make a diff in what happened.

DP330L Memorial page

http://www.davros.net/330L/330l.html

bpryor

My Feedback: (45)

Darvos,

>>I had the aileron setup at maximum mechanical advantage,

Well, it sounds like you did everything right. I don't have a clue what the problem is with your plane, but I still don't buy it's a general design flaw because mine and the 100's of others that are flying without problems would all be scraps too if that was the case.

>>as I really don't see the need for crazy aileron throws for most 3D maneuvers

You're right, most don't, but the ones that do do. If you want an all around 3D machine capable of all 3D maneuvers, you need the big ailerons too. Leaving big ailerons off of a plane advertised to be 3D capable would have been a design error.

>>The bottom line is if you are going to produce am ARF aircraft with these mods, it should be setup for it.

I believe it is. Your problem is not unique, but it is a rarity, which as I mentioned points to a problem in your specific plane, or in your setup(which sounds right on from your description).

>>I don't think 20 more oz's of torque would make a diff in what happened.

You're right, the extra 20 oz on your plane probably wouldn't have made any difference.

RCP57

My Feedback: (25)

Unique????????? This problem is NOT unique!!!!!!!!! Granted most of these ARFs are flying without any problems, at lease the ones we know about. There have been numerous postings here on this board about aileron flutter. I had the same problem on my first flight. During my first flight I kept both sticks ready and waiting for the infamous flutter. At half throttle the plane flew fine. It took one click of down elevator and one click of left aileron to trim. As soon as I went to 3/4 throttle all hell broke loose. The airplane shook so hard I could not tell what kind of plane was in the air. When I saw it having a seizure I chopped the throttle and pulled the nose straight up. I managed to bring it down without a scratch making all turns with the rudder since my ailerons were dead. The only damage was two badly bent 4-40 aileron pushrods, two broken clevis, and some minor damage to the aileron servo hatches. It took 4-40 pushrods encased in 3/16" carbon fiber tubing to solve the problem. The airplane is powered by a FPE 2.4 swinging a MenzS 20 x 10 prop, digital servos, and all gaps sealed both top and bottom. Everything is done the correct way, at lease my part of the airplane. There are several items I found that are poorly done on this aircraft all of which I changed during assembly. Along with the very poor customer service I can easily state that I will never own anything designed, built, or manufactured by DP. In fact, the aircraft is for sale with or without the engine and radio gear. Anyone interested can email me directly.

Next up will be a Cardon 35% Edge with a DA 100. I purchased the kit just the other day.

bpryor

My Feedback: (45)

RCpilot77084 reread my post.

I said "Your problem is not unique, but it is a rarity, ", and I stick by that. The dynamic here is that whenever there is a problem with a plane people post about it and and some people tend to come to the conclusion that it is a general problem because they have read two or three reports of the same problem. What you need to do is weigh the number of reported problems against the 100's of DP Extra's flying that you have not heard it about.

Like I said, there is an issue, and that is that the stock setup as documented is not adequate for use when flying with a gas engine....and now maybe people can understand why Dave Patrick does not recommend gas. I knew when I built this plane that it was not recommended for gas and I made the appropriate adjustments in setup to compensate for the additional stress put on the plane when flown with these types of motors. If you ignore his recommendations, which I obviously think is ok to do, you need to have the knowledge, or gain the knowledge, to make the correct mods to ensure the plane is strong enough to handle the addtional loads that a gas motor will add to this airframe. If you go outside the bounds of the recommended engine, then you are responsible for the consequences, not the manufacturer.

Flymyplane

My Feedback: (24)

OK, you guys have me scared! I have a DP 330L almost completed with H9 titanium pushrods 4-40 size, Rocket city harware, and Zenoah G45 mounted to the front. I have 8 CA hinges in each aileron (one right at the horn!) and 5 CA hinges in each elevator half and rudder. I have one Hitec 5645 digital servo in each wing half. I have Hitec 945s in elevators and one Hitec 5645 in the Rudder PULL PULL. Im planning to use 18" to 20" props on G45. Could t be that 20" props or larger are causing the airplane to "fall apart"?? Could be to much torque or something?? I know a guy flying one with a OS 1.6, and he does not hold back the speed! He flys it like a pattern plane. He has had no flutter problems, although he had balance problems. Im hoping with the G45 it will give the balance weight that I need, and allow me just enough power, but not too much to rip the airplane apart. Im also hoping that since Im using metal gear servos, they will hold up better to the resistance of those large ailerons. ?????????

Ben Diss

My Feedback: (23)

No need to worry. I'm flying mine with a Taurus 2.6. My elevator servos are in the stock location, and I moved my rudder servo into the tail to get the CG to 6". I have strong digital servos throughout the plane and have never had a problem with flutter.

-Ben

On_Final

Gee Wizz, now my knees are knocking. I have my DP 330L all set up and ready to go and now I'm not so sure. It is built stock with all supplied hardware except that I replaced all push rods with Dubro 4-40 rods and clevises. I also replaced the wheels with TT 3 1/2" wheels (rough field).

I have a OS 1.60 up front with a 17X10 Menz prop (might replace with a 18X8). Futaba digital 9151s all round except for trottle which I used a 9001. The elevator servos are in the tail. Quite a bit of lead up front. Don't know how much but I kept adding until it balanced at around 6".

Maybe I will give eveything the once over again and postpone the maiden till next weekend.

John Wells

My Feedback: (10)

Ditto. Tomorrow I'm flying mine for the first time. Single, metal gear JR's on each aileron with a Moki 210 and 20X6. I guess I should take a trash bag with me. I'll let you know how it goes.

JW

davham

My Feedback: (4)

Geez,

Give everyone the spooks why dont ya
Mine has a zdz40 and is finally going up this saturday.
I used hitec 5625's all arround except throttle and running 6 volts.
Total wieght w/o fuel is 16lb .08oz. This is without wheel pants and using the included go-flat tires.
Those with the zdz, who long before the stupid thing is broke in or at least runs well? Sluggish transition and from wot back to idle it will die if I dont goose it a little. Has 3 24oz tanks through it.
And I wont even mention the goofy throttle linkage. Trying to get a reliable/repeatable idle with this lever placement is a joke. Squeeze a link between both needles and thr stop screw, yeah right! Maybe I should ask this elsewhere.
As you can see, I'm unhappy with this so far. Hopefully this will improve as I get to fly the plane. That is if my wings dont blow the ailerons off first. haha

Dave

RCP57

My Feedback: (25)

My intent was not to scare anyone who is about to fly this aircraft. I posted my personal experience and opinion. The plane flies fine now that I made all the adjustments, changed all the hardware, but not as good as any of the print reviews. I get a little pissy in my old age when I see someone defend a product that has so many sub-standard parts included with an ARF kit claiming to be 3D ready. Somewhere in my previous post I should have put “DP does not recommend a gas engine in this airplane”. That seems to be the “OUT” being used as an excuse for the flutter problems some airplanes are experiencing. I guess the flutted problem would not exist if you use the OS 160 FX putting out 3.7 hp instead of the lower 3.1 hp rating of the FPE 2.4 engine. Maybe the OS 120 FS with 2.1 hp would stop the flutter. Then again it could be the large built-up ailerons instead of sheeted or solid pieces causing the problem. Why not delete all the hardware in the package and cut the price by $3.00 on the retail side. I’m sure that if you bolted up an OS 46 FS motor you could use the 2-56 push rods and clevis provided, right? An aircraft of this size capable of most 3D maneuvers regardless of the engine should not have this low level of hardware included. I have seen "you need to use throttle management with this airplane" printed a number of times. Why not just build an airplane of this size properly, now that would be something to work on. Give me a break!

I’ll stop now before I really get started.

krayzc-RCU

My Feedback: (31)

Flyers with those huge ailerons:

how well does the plane do the rolling elevator/harrier?

bpryor

My Feedback: (45)

Hi RCpilot77084,

>>I get a little pissy in my old age when I see someone defend a product that has so many sub-standard parts included with an ARF kit claiming to be 3D ready.

There's no reason to get pissy. You have your opinion which is quite welcome and other people have there's. As a matter of fact I totally agree with you on this. It doesn't make much sense to include poor hardware, but that's marketing for you. It's just too bad that it's the inexperienced builder that gets bitten. If you're referring to me with this statement, I've never defended the hardware included with the plane, I'm only defending the planes design. I think including poor hardware is totally misleading for an inexperienced modeler, but certainly someone that has built a lot of planes should know up front the hardware needs replacing.

When I got the plane way back last September, there was no feedback on the plane, but it was obvious the hardware needed to be changed, and that was a big reason I wrote my detailed review of the plane so hopefully people that weren't experienced could avoid the pitfall of using the stock hardware.

I don't really see the point of only getting upset at DP about this. Virtually any ARF you buy comes with the same poor hardware. DP is hardly the only one guilty of this. If this is the way you feel, then you're doing the exact right thing buying a kit that doesn't come with any hardware and you can put in whatever you want. I personally don't have the time to build kits, so I accept the limitations of virtually all ARFs and compensate for their inadequacies(building an ARF with mods still takes a fraction of the time that building a kit from scratch does) and I've never been disappointed. Of course, just like a kit, there is absolutely nothing preventing you from throwing away all the hardware in the ARF and buying whatever you want to use. It might not seem right, but I don't see the big deal. Hanger 9 offers great hardware for their 33% planes....for $150 extra.

>>That seems to be the “OUT” being used as an excuse for the flutter problems some airplanes are experiencing.

It's not an out, it's a real factor in potential flutter issues. A gas engine that weighs double what a glow engine weighs adds significantly to the wing loading of the plane, and even if you don't consider increased vibration, there are significantly higher and different loads being put on the airframe. If you're going to run a gas engine, whether it has more peak HP or not(which isn't what really matters anyway - I haven't seen many OS 160's turning 20X8 props as does the FPE), you're going to need to compensate by beefing up the airframe(though in this plane's case, it really doesn't need any mods to the airframe), servos, and linkages.

>>I have seen "you need to use throttle management with this airplane" printed a number of times. Why not just build an airplane of this size properly, now that would be something to work on. Give me a break!

Throttle management is necessary with virtually all giant scale aerobats(including that Carden you're planning on building). None of the 3D capable planes are designed for full throttle blasting around as some people do with small glow powered planes. These planes are typically way overpowered for good 3D performance, and of course with oversized controls, and none of them will survive uncontrolled speed.

Flymyplane

My Feedback: (24)

Before I mounted my G45 to the 330, I called DP models and asked them. I was told by DP Models that the G 45 would be OK for this model. So, since I had the engine already, I decided to mount it up! As I have heard, there have been tail heavy conditions with this plane. I figure with the G45 up front it should balance out with the servos in the rear for elevators.

As I also mentioned in a previous post, I plan to use 18" props, as I already had them. Im pretty sure I can use them on a G45, and it should work out well! (I hope!) Im wondering if the 20" and larger props are causing some flutter problems, along with fast speeds! Like BPryor says, throttle management is key!

bpryor

My Feedback: (45)

Hi Flymyplane,

I'm surprised that DP told you that it was alright to run the G45. They've obviously changed their tune about gas engines, and it's about time. I think the G45 is a bit heavy, but definitely will work fine. I remember someone that put a G62 in theirs and it flew ok...but that definitely wouldn't be my first choice.

By all means put all your goodies in the rear. You're most likely to have the reverse problem with the G45 and need some extra tail weight. I'm guessing you'll need your receiver batteries in the rear of the of the cockpit area to balance correctly.

As far as the prop size, 18" sounds a bit small for that motor. I'm not an expert on the G45, but I'd guess a 20X8 or 10 would be more like it. Don't be afraid of the large prop sizes for this plane, they will work better overall. My favorite on my Taurus TS-42 ended up being a Zinger Pro 22X8 and I tried a bunch of props on it from 20X10 to 22X10 (Moki, Zinger, Menz Ultra and S).

Flymyplane

My Feedback: (24)

Hi Bpryor,

Yes, I was surprised that DP gave the ok as well! I realize it may be a tad bit heavy, but Im not much of a 3D guy yet. Im just hoping for good general performance. I have seen this airplane with the OS 1.6 doing screaming flybys with no flutter, but that is only one plane. I wil probably experiment with different props, but will try the 18" first since I already have them. You may be right, it might not be enough prop. Thanks for your input and suggestions! Much appreciated!

Davros

My Feedback: (1)

Well guys, great to hear all the different input for you. Bottom line is this. I am NOT an novice builder, I am an experienced pilot. I upgraded my hardware on the ailerons. I used HIGH Torque servos. I flew the plane VERY slowly...It was not OVERweight, came in at 15lbs, 4 oz with the TME smoke system in it. And it still fell victim to flutter. If you look on DP website, they talk about a Moki 1.8 causing flutter..... SO let's not just say it was THE GASSER!! All I know is that I am OUT well over $600.00 bucks after 3 minutes of flight time. I just hope the DP comes to the plate and refunds me my cash or at least replaces the kit...btw, the BME50 ran FLAWLESS from the first startup!! Sure hope she did not get hurt too bad..it looks pretty good..Will send it in to them the have them check it out...

Ed Jarold
President
Cleveland Radio Control Club

www.clevelandrc.com
www.davros.net/330L/330l.html

davham

My Feedback: (4)

Why in the world would DP give you the green light to use a G45?
I spoke with the man earlier last week about a canopy problem and he asked what I was powering it with, when I told him a zdz40 he strongly advised against it and suggested a moki 210. Told me the moki was much lighter and more powerful. I belive a zdz40 is lighter than a G45, what gives?
The manual states a moki 180 is too much power.
I not trying to discredit you but this strikes me as being odd.
Dave

dirtybird

My Feedback: (5)

With the addition of $10 in parts you could make this and any other airplane flutter proof

otisflies

Care to elaborate????