I have a WM Zen 50 and although I have been very happy with the kit, it approaches super hot. Of course, I am mostly to blame, putting in a .61 in when a .46 is recommended. I thought the extra power would be welcomed and the CG is only slightly forward (less than 1"). What can I do to slow it down? I thought about 2 things.

1. Use the flaperons... but since the ailerons are toward the outside of the wing, I heard it is not advisable
2. Put the CG where the factory suggested. The battery is already behind the CG. I will have to add around 2 ounces to the tail. But will the right CG affect the approach speed?

I wear down wheels like there is no tomorrow whenever I land trying to stop it. Yesterday I rammed the muffler into a concrete slab and cracked the engine mount...

Plus everytime I come in for a landing, I swear I will have a heart attack.

My other planes

WM Piper Cub .26 w/O.S. FA30
WM Ramber 30 w/ Y.S. FZ63
WM Zen 50 w/ T.S. .61
CMP(KMP) Cessna Skylane w/ASP(Magnum) 4S .61

Having the recommended CG is absolutely a must.

Re-balance your plane and get the CG to be further back. A nose heavy plane will tend to have a hot landing.

Once you have the CG right, take the plane a few mistakes high, and find out what the plane's stall speed is. You will probably be surprised at how slow it is. Then, land the plane at closer to stall speed. Nose heavy planes have much higher stall speeds.

Finally, with the .61 on the front, you can probably do with a low-pitched prop. Try flying with a 4 or 5 pitched prop. This will give you lots of torque, and also be more of an air-brake when the engine is at idle when landing.

BUT, your first thing to correct is the CG.

gus

Gus is right - nose heavy planes need more speed to keep the elevator effective. Every plane should be balanced properly - even for beginners. People will say "nose heavy is better than tail heavy." Well, nose-heavy is still bad. I also agree about the lower pitch prop.

Slightly nose heavy is better than slightly tail heavy. But more than "slightly" of either can lead to a broken plane. I totally agree that moving the CG back can do wonders for slowing down your approach speed.

Looking at your other planes, though, you should keep in mind that a Zero is going to land faster than any of those, no matter where the CG is. You'll definatly want to get up high and do some test stalls and slow flight practice to see what it does.

gus and CafeenMan are absolutely right about cg. Bigger motors mean more than just more power; I can't believe the number of guys that cram a bigger motor into the nose and then blame the airplane design for not flying right...JIM

I completely agree with these guys......and if balanced correctly, the .61 can actually help slow you down....since you'd have a larger diameter prop on it. (definitely go with a lower pitch also, like gus said)

Mike

Move the cg back as suggested and ride final while holding more elevator to help slow it up. Add lead to the tail to ballance it and it will slow down. Learn to do it high so you know where it will stall.

But not better than balanced which was my point. A plane should never be nose heavy or tail heavy.

Thanks a ton for the advice. I will definitely rebalance the plane to put the CG where it belongs! If only I could do it sooner!!! I won't be able to fly for at least two weeks... but when I do, I'll make sure to take all of the advice in mind.

CafeenMan, that elevator comment rings so true!!! Why didn't I think of that? (there must be a acronym for that... WDITOT?)

Michpitssman, I definitely don't blame the plane completely... But when I first installed my FZ63, which is only marginally heavier than the 46FX, I needed around an ounce of lead on the engine mount to balance the plane. At that time the battery pack was forward the CG next to the tank. So I naturally assumed that the plane could take on a heavier engine... but this China made engine is very crap (I know that's poor grammer but hey, I like the way it sounds... better than just "crap" or "really a peice of carp"). I am turning only a 11 x 7 prop and only at about 10-11k rpm. And I have to open the needle 3/4 turn to get it pass the vertical test. I refuse to go to a 11 x 6 because that was what I was on with my 46FX that has since seen the last of its days when my pattern plane smashed into the ground, disentegrating the front half of the fuselage.

Anyway, I agree with you... overpowering does not equal overperforming...

I’m surprised that no one has mentioned the obvious. Trim the aircraft for slow flight before beginning the approach. Unless the wing loading is really high, operating at a higher angle of attack will slow the airplane down. Operating approximately 30% above stall speed is the way full scale aircraft are landed and it works for models as well. If the idle is set reasonably low (3000 rpm or less) the approach speed can be controlled with the trim. If this doesn’t work, the problem isn’t too much power, it is too much weight.

While propeller changes, cg location, etc. effect drag a little, the determining factor of approach speed is wing loading. High wing loading equals high stall speed equals high approach speed. Low wing loading equals low stall speed equals low approach speed. It’s really as simple as that.

Thank's LouW, I will try to trim the plane as suggested with a higher angle of attack. But the plane does have a very high stall speed and has stalled upon final approach a few times with very unhappy results. I will, however, take it up to two mistakes high and work on my "slow" flying...

Hi FOURSTROKE! The correct ways to fix the problem are usually the most difficult. Putting your plane on a diet will work wonders if you are willing to put in the time. Going with pull/pull controls and junking the steel rods is a good move. It's hard to find things in the wing to eliminate unless you are willing to strip the covering, and unless you are capable of making judicious decisions on what wood to either thin down or remove. For hands on advice, a modeler who has experience with lightly built planes in this size range will most likely be a guy who flies pattern, if you have someone like this around, ask for his help. Saving weight is about taking a little here, a little there. The use of lead anywhere should only be for the sake of finding where your for and aft CG works best, but once you find that out, then it's up to you to move gear around , even if it has to be the engine. If you are totally in love with the idea of a .60, at least use a prop with as much diameter as the engine will tolerate. A 13-4 would be good for starters, and will let your engine idle a bit lower, [as someone else mentioned]. Put your hobby skills to work and move the firewall back. 1/8" ply with tri stock corner braces, and a little glass cloth has worked with 60 size pattern planes for years. If you have an engine mount system that is strong enough to break an engine lug before part of the airframe, you are flying a BRICK my friend.I'll bet that you could get 1/2 pound of dead weight out of a typical kit plane in this size category, which is a significant amount. I have had great results with a .60 size P51[ that just had ailerons] going with flaperons that were coupled out of phase with the elevator. Try a 10% mix of flap to elevator, if your CG is right, you will be amazed at how well you can flare the plane to dump speed right before touch down. I got to where I favor short and steep approaches with the nose up. If you can detect any wing rocking, that is your indicator that you aren't getting enough air past your ailerons, and it's time to lower the nose and be ready to pour on the coal. Our club field only has 240' of runway, with houses 500' off each end, so the most successful warbird kit builders around here leave alot of the wood in the box, and or substitute with lighter wood and better building methods.

Thanks, combatpigg... I will most likely replace the engine with one that is lighter so that I don't have to add any weight. that will be the first step. Then I will try to get use to flying with a little flaperon. As for stripping the plane... I'd rather build one ground up! But thanks for the words of advice.

Hi again...

Do things in stages.... over-powering a plane is not unusual. Instead of changing everything at once, just start with getting the CG right. Typically you should move the CG 1/8" at a time, so being 1" off is a long way for a model plane. Get the CG right, and if that does not make the plane fly to your satisfaction, then only then would I go and replace the engine. Using lead at the tail is not too bad a deal to try things out a bit. Stick the lead to the surface, fly a bit. If you are happy, only then do you look in to shifting gear around to avoid adding lead. Put an extension on the battery, and shift it further back. Move the throttle servo back.... elevator and rudder servo's back, etc.

BUT, do things one change at a time otherwise you will learn very little about what affects your plane's characteristics.

gus

GOOD ADVICE GUS! Changing one thing at a time teaches you more about what you did, rather than trying to figure out what did what with several changes at once. FORESTROKE...You bring up a good point about starting over. A favorite project of mine when I was a kit builder was to order my own contest grade wood, and build a better version of a plane that I was already flying. An easy way to make templates is to photo copy and laminate the plans, then cut the laminated patterns out. I have used 2 layers of clear cellophane package tape for the laminate. There are so many outstanding .45s on the market that your decision to go back in size will pay off. MORRIS HOBBIES has a good deal on a ROSSI 45 with a mini tuned pipe. The Webra 50 was rated as the 3rd best power to weight engine in a survey that was done by one of the US model magazines. This engine will turn a 12-5 prop good enough to haul 7 pounds straight up. I think this engine would be hard to beat. There are others, like YS that also have great reputations, but I have no experience with, so a trip to the engine forum would be a good way to do some research on what's the latest and greatest in the 45-50 size range. Good Luck, and have fun. You have an interesting project on your hands!

One way to guarantee good landings is to work on approaches. The full-size practice of stabilized approaches works just as well with R/C models. One thing I've found is that proper use of the elevator trim helps landings a lot! Take the plane up high enough so that you can stall it safely, and find out what airspeed is comfortable. Slow the model down until you have a good approach speed. Now play with the elevator trim until you can move the throttle to your approach setting and have the model fly an approach without your having to hold any elevator pressure.

Now you can concentrate on keeping the plane level and not worry about the proper amount of back stick. Moderate the descent rate with throttle. The cool thing is that the approach setting will make the model climb when you add throttle and descend when you take it back.

One model I had would have a perfect approach speed and descent rate when I moved the throttle stick to full idle and added four clicks. I'd then move the elevator trim to full aft. If I could keep the model level through the entire approach, I'd invariably make a good landing.

The main key is that your normal flight position for the trims is neutral. Make any adjustments to the clevises so that your normal flying is with the trims in neutral. That way, you never have to worry about where they trims should be when you're ready to take off on the next flight. Just make sure they're centered and you're ready to go.

With transmitters that have electronic trims, you can use 'beeps' instead of 'clicks'. Some top flyers actually modify the ratchets on their throttle sticks to make a stronger detent for the approach setting. So an example for landing approach would be: "throttle to the setting (extra large click), four beeps of trim, and keep it level to the runway".

Of course, you have turns involved, and have to allow for wind, but like everything else, if you can simplify some of the procedures, the rest come easier.

bax

Gus - I'll try to alter things one at a time to isolate the problem. I'll try to move the battery back a bit first (It's already pretty far back there and the fuse is not exactly "roomy") Then add weights at the tail to get the recommended CG. If the lead works then I'll see how much more gear I can move back in order to take off some lead... I hate to put lead on a plane...

Combatpigg - I have a Y.S. 63 and that thing hauls!!! I originally had it on this plane but it was actually too light and I had to add weight on it. Plus, it goes through fuel like **** through a goose

Bax - I have electronic trim on my tx so it may be a little more difficult to get the right trim every time but it will be a good start. What do you recommend about mixing throttle - elevator? I assume that is not recommended as it may lead to ballooning mid-flight. But if I could turn the mixing on and off... what do you think?

FORESTROKE! There is no such thing as a powerful engine that is too light. You should have your mouth washed out with soap for saying that!![ or your fingers dipped in boiling oil for typing that!]

Combatpigg - Hehe... It was too light for the plane... serious... I never thought I'd have to add weights (about 1oz) to the motor mount. I now have it on a Rambler 30 and it goes vertical at 1/2 throttle... it's a treat since all my other planes seem more "scale power". By the way, that Y.S. is a blast.

HI FORESTROKE!! I've never owned a YS, and wondered if the pump is a trouble free, no special attention type device, or something that needs help once in a while to keep working the way it should? I had an OS 1.20 with pump that needed to be spanked once in a while to run right.

Wow! I run my WM Zen-50 with the aforementioned YS-63 on a 12x7 APC and it performs wonderfully (At least as good as I can do...) I have my flight pack back BEHIND the servo tray so the CG is back where I like it [X(] I do think your fast landings are because of the weight of the 61 also though, the plane likes to come in fast-

When I first got mine I came in WAY too fast until I realized, as someone mentioned, that slow flight could be very slow as long as you are on the power when needed- Mine now comes in tail down and I can touch the tail-wheel first, and not be in danger of a pancake stall-

I absolutely LOVE this plane! It definitely flies better than I do- [X(]

Great advice above- just thought I would throw my hat in cuz' I have a similar combo- And yes it CAN hover with the 12x7 APC

Combatpigg - the 63 is a great engine and the pump works like a charm. I've had no problems with it so far.

Razor - I agree that the Zen would be great plane if I could get my own act together... but one thing is clear, I think I'm going to pull the 63 off the Rambler and back into the Zen where it was suppose to go in the beginning... that thing does make a ton of power! The China .61 is not very responsive and often idles irregulary high for a while before winding down. However, as mentioned earlier in this thread, I will try to get the CG done first before I do anything else! But thanks for that info!

HI RAZOR! You don't work for that model company DO YOU? That's inspiring to hear someone who can say such great things about a .60 powered warbird! Imagine hovering such a plane 20 years ago! Your testimony is enough to make me want to go out and buy one! Are you working on a commission? If so, I'll throw ya a bone!

Combatpigg - actually it's not a warbird... it's a pattern plane. WM has a Zero Fighter but that's either a .61 or a 1.20. I do have a Corsair, though... purdiest plane of them all...

Nope- I sell insurance [X(] As mentioned the Zen is a pattern plane that is really not designed to hover, especially with a 12x7 but I goof around a bit-

The YS-63 is a perfect match for this airplane! I take it with me EVERY time I go to the field-

It is also known as the fastest rolling plane at our field! I cranked the ailerons up quite a bit- Looks like a torpedo!