My Old Foggy Won't Fly!

[rfcgt]

I'm having some major problems with a scratch build Old Foggy (not a speed build kit). It's unflyable. It rocks violently from side to side almost from launch. A half dozen or so rocks and it rolls over and lawn darts into the turf. I've tried reducing the throws and desensitizing the controls. It helped some, allowing me to get some altitude but the next maneuver I make, it starts its rolling, wing over and back into the lawn. Everything seems to be cut, sized and assembled properly so, I can't figure out what I can do to salvage this thing. By the way, after several hard, nose first crashes, the air frame is in remarkably good shape. For being made of foam board the plane seems very strong. Any help will be appreciated.

Thanks
rfcgt

 

[photohap]

Couple of things. Check your CG, is it pitching up? If so move your battery forward some. Also is your motor secured down good? Is your prop secured good?

What size of battery and motor are you using.

 

[ts20fan]

I had a very similar experience with my Old Fogey, just mine managed to come down safely, after a couple of minutes of white-knuckle flight.

While I only flew it once before I gave it away to be a static model, this is what I believed:

• Since I used the original FT Plans, the vertical fin was too small, causing the "dutch roll" that you are describing. Did you use the normal FT Plans?
• Also, from the bottom of the folded wing to the tip of the polyhedral, I had about 8.5". Looking at other pictures of properly flying Old Fogeys, I believe this to be excessive, and possibly another cause of dutch roll. Look at your wingtips compared to some others on the site that fly well. Are yours excessive, like mine?

I also agree with photohap, your CG could also be an issue, if the plane seems to nose up and rock, I believe that would more likely be a CG issue.

This is just my opinion, as I only flew that plane once, and there are much more experienced people here on the forum.

 

[rfcgt]

Wow, Thanks for the quick response. First, the CG was measured right at the wing break, about 3.5 inches from leading edge. I set it up slightly nose heavy. It still seems to fly a little tail heavy. I've noticed in the videos that it does fly dragging it's tail some. The power pod seems tight, but it wiggles a little, much like my Nutball. The prop is tight.

I used the plans that were on the site in November 2015. I don't know of any other modified plans.

I've used both 2 and 3 cell. The only difference I can see is that it hits the ground harder with the 3 cell. I'm using the Suppo 2208/17 motor so there is enough power. Also using a 9x4.7 prop. The polyhedral is 2.75 inches measured at the wing break.

rfcgt

Just read a post from "mike123". He said to cut the top half of the fuselage off.

 

[Mostly Harmless]

Sounds very much like my first experience with the Fogey. Very twitchy, unstable flight -- barely controllable. I found that moving the c/g forward of the indicated point helped tremendously. It took a little experimentation, but I ended up using larger batteries -- 1700 mAh, for example. Sure, it makes the plane fly a bit faster, but better at handling any breezes. Once I did that, it flew quite nicely.

As you can see from the video, the design is still prone to Dutch rolling. Others have addressed that by extending the rudder vertically a few inches. I left it as is because I thought it a good training device to practice controlling the roll and keep from over-controlling.

Additionally, make sure your power pod is aligned with the inside top of the front fuselage. Also, make sure you're not applying too much throttle -- if you're already a little tail heavy, excess torque can exacerbate instability.

Keep experimenting -- that's one of the joys of this hobby.

 

[ViperTech]

I fly my fogey with the cg located 1" in front of the wing break. Throttle needs to be kept on the lower side as the plane is apt to pitch up with heavy throttle, due to the massive lift the undercamber wing generates. I use 1000 to 1300 Mah 3s batteries. Fly in as close to zero wind as possible when learning this plane and getting it trimmed out. Slow easy movements on the sticks are a must! when you have the cg and trim right this plane will almost land itself. What you are describing sounds like too much throttle and or a cg issue. Keep trying be patient, He is a slow flier so you need to be a slow pilot.

Here is my old fogey, this is a couple years ago. I still have this plane and fly it. the cg was still off in this video and I was very jerky on the sticks still a noob too. You will see when it comes back into the wind how it shoots the nose up....tail heavy. Maybe this will help?

 

[rfcgt]

ViperTech, are you using the larger capacity battery to add more weight forward of the cg? What is the prop you are using?

 

[Garret234]

If you have a 8x4.3 prop try that one. My brother put a 8x6 on his old fogey and it too was un flyable.
Good luck and don't get discouraged, one of my first planes was the old fogey and I found you want to respect his CG.

 

[ViperTech]

ViperTech, are you using the larger capacity battery to add more weight forward of the cg? What is the prop you are using?

I use the larger battery for extended flight times more than any thing but it does help with cg. I use adhesive wheel weights when I can't get the cg right with battery position. I use a 9x4 slow fly prop.

 

[Crazy Goats]

I have an Old Fogey and I love it! The CG is not on the wing break though. Its about 1 cm forward of it. I use a 8x4 prop and the plane only dutch-rolls when I want it to. I am using the b power pack from FT, and a 3s 1300 lipo. My controls are a little touchy, but that's because the dual-rates on my DX5E are broken, and they are stuck in high. it is the speed-build kit though. I hope you can figure it out!

 

[guitchess]

While I haven't built the Old Fogey, I have the Old Speedster, and since they have the same wing, they suffer from some of the same flight characteristics. It sounds to me as though it could be a wing warp issue or possibly too much power.

In my limited experience, this type of wing is very sensitive to wing symmetry issues. I came in for a hard landing with the plane flying fine. With no obvious damage, it proceeded to dutch roll and otherwise became unflyable. On closer inspection there was a small crease close to the seam that was allowing the wing to flex about a 1/4". Once reinforced, it flew fine again. I would remove the wing, set in on a table, and check it for symmetry. If the flatness and polyhedral aren't within an 1/8" it could be your culprit.

Too much power can also cause flight issues. Torque roll could be making the plane roll, the polyhedral recovering, then torque rolling with more momentum to the ground, hence the dutch roll.

I'm leaning more toward the wing imperfections, but I'm still a novice with limited experience. So, just keep at it.

 

[Winglet]

I have successfully built and flown over 200 RC Models in my life time. I have built the vast majority of all FT designs and love them. The Old Fogey however is one of very few designs ever that just won't fly very well for me. I tried everything just short of so completely redesigning it that it wasn't even a Fogey anymore. Finally gave it away for a kid to hang in his room. My suggestion is to do the same with yours and move on to one of the other great FT designs. This one isn't worth the trouble. May I suggest the FT Flyer or Tiny Trainer. Good luck!

 

[Mytmerc83]

IMHO listen to ViperTech he helped me with my sons old fogey, I too have flow lots of different planes. The old fogey will fly and fly ok remember it's a slow flyer so the more speed the worst it flys. Change CG slow it down and it should fly great. My sons is a scratch built also.

 

[CrashRecovery]

The key to the fogey wing is getting the dihedrial (how ever its spelled) correctly on the two ends. If they are too steep it will always do the "dutch roll". Second is if the wing is in any way warped it will not fly properly. I went through three wings with my son's fogey before we got it perfect

 

[Jimmyp]

I didn't have any luck with mine. Just cut it up last week for parts which are now on the FT- Arrow

 

[Larry Paine]

Mine won’t fly either! I built mine un August and Fussed with the Aura board. Finally found someone to get me into the right receiver. However, that’s not my problem.

whe I add RPM’s to start flyimg, the nose pulls down. It did the same when I had th AR620 it (spare waiting for another plane). I tried flying it yesterday and I got a nose plant like was described above.

Mine is from the speed build kit with the swappable power pod from the kit.

The motor is in line with the power pod and not pointing down. The power pod is pinned with a skewer where the kits saws it should be.

thrust angle on my mini apprentice is definitely pointed down and right so seeing this straight on is confusing for the thrust to go down like it does.

so, what do I need to do to fix this? This is my first FT speed build kit.

Larry

 

[tcalico]

Mine won’t fly either! I built mine un August and Fussed with the Aura board. Finally found someone to get me into the right receiver. However, that’s not my problem.

whe I add RPM’s to start flyimg, the nose pulls down. It did the same when I had th AR620 it (spare waiting for another plane). I tried flying it yesterday and I got a nose plant like was described above.

so, what do I need to do to fix this? This is my first FT speed build kit.

Larry

My first experience with Old Fogey was discouraging, as it kept nosing down too, but once dialed in, it is my go to easy flyer. The CG is forward maybe 1/4 inch of the crease in wing and mine was found nose heavy as built, so a 3s1300 battery is placed under the power pod at about the CG, not under the front like in the build videos. I believe the original motor from the video was much less weight than the "B" pack motor I installed. Next I finally realized after a few white knuckle flights, that I had to keep pulling back on the elevator stick to keep it in the air. To resolve this, I physically trimmed the elevators up few degrees and kept the sub trim near zero on my radio. The build video for wings like the Arrow say they were supposed to be built with "up trim" or they will not fly. For some reason my Fogey needed that up trim too, maybe from the heavy motor, then it was perfect.

 

[Piotrsko]

There is a "Thing" called angle of incidence, which biases an airfoil to be slightly nose up (positive) in flight. If it isn't positive, the wing does a controlled stable dive into the ground. Flying wings this force is also called reflex. Holding the horizontal stabilizer level, you should see the nose of the wing point up or holding the bottom of the wing plumb, the nose of the H stab should point visibly down. The H stab can be level, but will need some up elevator to compensate.

 

[Monte.C]

Wow, Thanks for the quick response. First, the CG was measured right at the wing break, about 3.5 inches from leading edge. I set it up slightly nose heavy. It still seems to fly a little tail heavy. I've noticed in the videos that it does fly dragging it's tail some. The power pod seems tight, but it wiggles a little, much like my Nutball. The prop is tight.

I used the plans that were on the site in November 2015. I don't know of any other modified plans.

I've used both 2 and 3 cell. The only difference I can see is that it hits the ground harder with the 3 cell. I'm using the Suppo 2208/17 motor so there is enough power. Also using a 9x4.7 prop. The polyhedral is 2.75 inches measured at the wing break.

rfcgt

Just read a post from "mike123". He said to cut the top half of the fuselage off.

hits the ground harder with the 3 cell.

 

[Larry Paine]

My first experience with Old Fogey was discouraging, as it kept nosing down too, but once dialed in, it is my go to easy flyer. The CG is forward maybe 1/4 inch of the crease in wing and mine was found nose heavy as built, so a 3s1300 battery is placed under the power pod at about the CG, not under the front like in the build videos. I believe the original motor from the video was much less weight than the "B" pack motor I installed. Next I finally realized after a few white knuckle flights, that I had to keep pulling back on the elevator stick to keep it in the air. To resolve this, I physically trimmed the elevators up few degrees and kept the sub trim near zero on my radio. The build video for wings like the Arrow say they were supposed to be built with "up trim" or they will not fly. For some reason my Fogey needed that up trim too, maybe from the heavy motor, then it was perfect.

Are you hand launching?

I just checked my plane and I have my 3S 1300 under the CG. Might need some adjustmen. I did notice the crash dislodged the Aura board and the serial receiver so I will need to do some repair there

I am glad to find someone that has had the nose down experience too. It has been discouraging to see Bixler install the electronics and have his planes just fly off without problems.

knowing I has the down thrust, I adjusted the elevator to have a small amount of UP also. My flight was not long enough to tell if it had any affect.

Thanks for the response. I was beginning to think I had an oddball setup.