plcline67

Flash 1940,
Where can I get Halco gear? Is there any others you'd recommend?

bigedmustafa

My Feedback: (2)

A number of manufacturers offer replacement landing gear braces for the main wheels. For replacing weak nose gear, look at Fults replacement hardware available at Tower Hobbies:

http://www3.towerhobbies.com/cgi-bin...&I=LXH125&P=ML

Combine a Fults dual bar nose gear assembly with an aluminum landing gear bar for the mains:

http://www3.towerhobbies.com/cgi-bin...?&I=LXJ922&P=7

...and you'll never have to worry about bending up your landing gear again.

Good luck and good shopping!

Flash1940

Here's a picture of the skid plate and the engine spacer blocks


Flash

Flash1940

I can't remember where I obtained that Halco landing gear....one thing for sure.....I've had it since the 70's. Not even sure it's being manufactured anymore. Here's what it looks like.....



Flash

yetti831

Great job. Looks beautiful.

Flash1940

The landing gear is just on there to take a picture. When it goes to the flying field....it will be on this homebrew stand.


Flash

plcline67

I just converted mine into a taildragger. After a few "not so perfect landings" the nose gear gets bent. Where it's bent is weak and will bend even easier the next time. My next plane is A H9 Ultra-Stick, which is a taildragger, so this should help me get ready for that plane. It's a little different on take off, but I like it.

goirish

How did you attach the wing in the front. I see you have wing bolts on it. I am in the process of putting one together and like the bolts better.

shadwest1

ya i agree i have had mine for a mounth and the landing gear was the firdt thang to go. i also orderd a 6 channel radio by tower i modifide the wing so i can put flaps on it to try to help with the landings i have a os la 40 on mine and its just hals ass on the landing what u think will it help. and i have triad rolls with with it and thay look like crap. do u think its cusze i dont have enouph throw in the allerons? ..........west

ES CONTROL

Try moving CG back  and a 4 or 5 pitch prop.     ( a long flat prop is a brake and gets you up faster on take off.)

cfircav8r

My Feedback: (1)

If you can ease the plane into a stall with the throttle at idle then your CG is fine. A stall doesn't always drop the nose it can just get a steep descent with a nose up attitude. If your engine is idling too high and/or you have a higher pitch smaller prop, that can cause it to not slow down well. The most common problem is most pilots don't slow down enough on final. If you wait for the flare to slow down then it will float down the runway, and you will overshoot. You can only increase the throw so much on the ailerons before you reach a diminishing return. Most true trainers will not ever roll fast and they are rarely axial due to the design, they just are not designed to do most aerobatics well. It would take some design changes to get a faster roll.

shadwest1

thanks for the info i just got done converting my wing with flaps to will see how that dose....west

Appfan

These planes work well as tail-draggers. I, and my instructor, converted mine before the first flight. Great plane - I still take mine to the field.

cayrick

I am late to the party on this thread but here goes.. My issue is the published CG location in the manual. It claims 89mm, and my response is not possible. Here is why!
First a brief explanation of the setup. An OS 46 power plant and battery behind tank. I normally put the plane on a CG machine, balancing the plane at the published CG point. I then use weights to make it slightly nose heavy say, 15-20 deg nose down for good stability. To achieve this condition I added 11-7oz. weights to the hind end. I am quite anal about adjusting the clevis on the elevator so the elev. lines up with the top surface of the horiz. stabilizer.
This being said I went flying yesterday and expected, if anything, given my setup, the plane would tend, if anything, to go nose down in flight. Instead, quite to my astonishment, it wanted to go into orbit which was totally unexpected. This was not a slight trim issue. The logical conclusion that I arrived at was, that if at 89 mm it is slightly nose heavy on the CG machine, but in flight it behaves as though it is noticeably tail heavy, then the "real/actual" CG must be less than 89 mm giving the rear weight a longer moment arm, making it tail heavy; in other words the true CG is less than the published number of 89mm. Being suspicious of the published CG number, I removed 3 weight segments from the tail for the next flight, as in the absence of better info, this will be a trial and error process. I invite any comments from other pilots who fly this model who have had similar experiences, or someone that can tell me where my thought process is flawed. Thanks!

SportsFans

Cut my teeth with 2 of these models...great choice, also with the OS46. If I remember right the stated CG requirement was in question, man that was along time ago. I remember having to alter this setting, moving the CG ever so slightly in the direction I thought was correct until it flew beautiful. It took a few tries, took my CG Machine out to the field with me to get it sorted rather quickly. Good luck bud.

Steve

cayrick

Thanks for the reply Steve. Confirms my suspicions.

TomCrump

I feel that your logic is flawed.

To me, you are confusing incidence issues with balance issues. A nose heavy model doesn't necessarily fly with a nose down attitude, and a tail heavy model doesn't necessarily fly with the nose high.

These things are controlled by the relationship of the incidence, wing to stabilizer, and by the degree of engine thrust, measured 90 degress off the datum line.

JohnBuckner

My Feedback: (1)

Hi cayrick first let me welcome you to the forum. TomCrump is dead on in his replay andf let me also include the fact that you have not actually balanced the airplane at the instructions suggestion of 89 Mm, instead you have actually balanced it at an unknown point forward of the suggested cg point and if as you say 15 to 20 degrees nose down ( some would say For Mother and Country) it is really nose heavy to excess.

Whenever balancing an airplane to instructions or just checking the CG to be able to return it to the same point after doing some repairs as well as just fine tuning the in flight CG always balance with the fuselage completely level and never a indeterminate angle down . The reason is simple it is next to impossible for say a designer to be able to convey to just exactly how much nose down.

John

hugger-4641

My Feedback: (6)

JohnBuckner and TomCrump have pointed out some of the flaws in your thinking. Let me add a couple more. An excessively nose heavy plane has a couple other negative characteristics:
1. It will tend to climb under power and will require excessive trim adjustments between low and high throttle settings to maintain level flight.
2. An excessively nose heavy plane will take longer distance to land, partially due to higher landing speed, and partially due to the tendency to climb if you add any power. This makes it more difficult to get a smooth flare and touchdown.
There is an old expression that is sometimes taken to extreme: "A nose heavy plane flies poorly, a tail heavy plane flies once". While true, an excessively nose heavy plane can take a lot of the fun out of flying it.

There is also another tried and true formula for balancing if you don't trust the specified CG. This can be a little more difficult with some wing profiles, but with the MKII, the wing is pretty much square. (Close to the same width from wing root to wing tip), so you should be able to check this pretty easily :
Measure the chord of the wing (distance from leading edge to trailing edge) and use 33% as your CG point. In other words, if the wing chord (width) is 12", a good starting point for the CG would be 4" from LE.
This should be nose heavy enough to give stable flight, but not so much to make it so "climb happy".
If I remember correctly, the MKII actually has a chord of about 10.5". If the wing chord is 10.5", then 89mm would be right on the money. So your error, as JohnBuckner pointed out, is probably due to trying to balance with the nose down instead of level.

cayrick

I appreciate all the replies. The first time I flew this plane it was balanced on a CG machine so that it was neither nose or tail heavy. I am not a seasoned pilot and the plane was totally uncontrollable and people were running for cover. Other flyers suggested adding weights to make it nose heavy and then it responded well. Subsequently I had a rudder issue and it did a "U" turn on takeoff and hit the ground. It had some damage which I fixed and the issue I described above happened subsequently. Taking your advice into account I will shim the motor mount for a little down thrust on the motor with washers and see if this makes a difference. It is still a little nose heavy after removing some weight segments from the tail and putting in a rigid frame landing gear arrangement to replace the flimsy existing wire landing gear which, according to others on this forum is another issue. Prior to reading these three replies I would never have guessed that engine thrust angles would pose a serious issue.

SportsFans

I had no engine angle issues just CG issues, and once corrected a thing of beauty. If you do shim the engine you're adding more weight to the nose adjust accordingly. Then finally are you using the wire landing gear that came with the model? It is the worst thing about the model. On take off if one wheel catches a rut it pull that wheel out of alignment (toe out) then the model takes an erratic path that can make for some scary takeoffs an embarrassing . I had to change to something stronger, but also something light. More food for thought.

Steve

Little Stik

I used to build and fly but it has been years since I have flown. I just purchased one of these planes to get the air under my wings. I have not received the airplane yet, but I am reviewing the manual. Would it be possible to run dual ailerons so that I can have more control? Where would you suggest placing the servos? Has anyone done this? Thanks guys!

hugger-4641

My Feedback: (6)

I assume by "dual ailerons" you actually mean dual servos. Or do you really mean you want to add extra ailerons?
As for dual servos, I haven't done it to an MKII, but I have to a couple other planes including the Avistar and Tower .40. It was really a waste of time on both. I may have gained a little roll rate on the Avistar, but this was probably due more to the semi-symetric wing foil. The MKII is a flat bottom wing like the Tower .40, so I don't think you would gain anything unless you are planning to enlarge the ailerons. On both of the planes I mentioned, I located a space between two wing ribs near inboard end of the aileron and constructed a servo mount which i glued to the wing ribs. I also reinforced the opposite side of the closest rib to stiffen it up.

Little Stik

If I were to go dual aileron servo; would you suggest to go side by side or front and back?

hugger-4641

My Feedback: (6)

I think you are talking about using the existing linkage and just connecting one servo for left aileron and another servo for right aileron. If this is what you mean, it will be difficult. There is not enough room between the linkages for both servos to go side by side, so that forces you to put them further forward , turn them on their side, put them outboard of the linkages, or maybe a combination of the these. If you put them further forward you will have to add another linkage to connect the servos arm to the existing linkage. I don't really think you would have room to put them outboard of the existing linkages and still fit into the fuselage without interference and still have enough articulation. On a larger plane you might be able to do this, but pretty difficult on this plane. Not saying it's impossible, but you will probably pull your hair out trying make it work.
Front and back will also be a challenge because the linkages are at the back of the wing saddle so there's no room to put one of the servos aft of the linkages. This means only one of the linkages is going to line up with the servo arm. This is going to force you to modify one or both linkages, and if you only modify one, that throws another big kink in the geometry. This is why I think it would be easier to forget about using the linkages and mount the servos in the wings near the ailerons.