OMP Yak build
04-11-2004, 10:12 AM
#230
Senior Member
My Feedback: (2)
Join Date: Aug 2002
Location: Acworth,
GA
Posts: 244
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Hey Embalmer, is that thing really struggling with the 91? Sounds like you're really bummed about the performance. I want one and wanted to put a ST 90 that I have or buy an OS 91 fx. I don't really want to drop the $$ for a big 4c.
I hope to see that thing out at the propbuster field soon.
Chris
I hope to see that thing out at the propbuster field soon.
Chris
04-11-2004, 05:14 PM
#232
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Vref,
My Yak with a Magnum .91 has plenty of power. It will hover at 1/2 throttle, and the engine still isn't broken good yet. Using ThrustCalc, mine is generating 15.5lbs of thrust with an APC 15x4. Don't worry about the OS not having enough. It will be fine. That said, I'm sure it would be awesome with the YS......
My Yak with a Magnum .91 has plenty of power. It will hover at 1/2 throttle, and the engine still isn't broken good yet. Using ThrustCalc, mine is generating 15.5lbs of thrust with an APC 15x4. Don't worry about the OS not having enough. It will be fine. That said, I'm sure it would be awesome with the YS......
04-11-2004, 09:23 PM
#234
My Feedback: (8)
Join Date: Jan 2002
Location: Atoka,
TN
Posts: 1,788
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Chris,
I normally fly a sledge that weighs less than 4.5lbs that is powered with a YS63. So my sledge shoots out of a hover like a rocket.
My OMP .60size YAK does hovers fine with a OS91 and stock muffler. But I wouldn't want any less power. I normally don't start hovering untill I get about a half tank of fuel or less. I am still working on getting the plane set up. I built it stock according to plans. I used all the stock wood.
I built me a moosecan for it. I tried it for a few flights and pulled it off. it makes my motor run hotter than it should. So I just bought some lower nitro/higher oil content fuel. Hopefully that will keep my motor form over heating with the moosecan. I am going to try that out this week.
I am sure you have seen Paul Swansons .60size Suk powered by a ST90 and moosecan. I build the moosecan system he is running on his. Our planes weight real close to the same weight, and his vertical is fine w/ the ST90 and moosecan.
My OS91 will pull out of a hover just fine. It hovers a little below half throttle. when you punch it to go vertical it takes it a little while to build up some speed.
I fly mainly fly at the Millingtonbarnstormers. But sometimes on Monday or Tuesdays, I will hook up with the 3D guys at propbusters in the afternoon and fly over there. I will gladly let you fly it and see what you think.
I really like the way the plane flys. It flys real light. So far in my opinion, the plane could either use to loose some weight or needs more power.
Like I said earlier, I have been flying a sub 4.5lbs airplane with a YS63 on it. so I am use to really, really, good vertical.
I normally fly a sledge that weighs less than 4.5lbs that is powered with a YS63. So my sledge shoots out of a hover like a rocket.
My OMP .60size YAK does hovers fine with a OS91 and stock muffler. But I wouldn't want any less power. I normally don't start hovering untill I get about a half tank of fuel or less. I am still working on getting the plane set up. I built it stock according to plans. I used all the stock wood.
I built me a moosecan for it. I tried it for a few flights and pulled it off. it makes my motor run hotter than it should. So I just bought some lower nitro/higher oil content fuel. Hopefully that will keep my motor form over heating with the moosecan. I am going to try that out this week.
I am sure you have seen Paul Swansons .60size Suk powered by a ST90 and moosecan. I build the moosecan system he is running on his. Our planes weight real close to the same weight, and his vertical is fine w/ the ST90 and moosecan.
My OS91 will pull out of a hover just fine. It hovers a little below half throttle. when you punch it to go vertical it takes it a little while to build up some speed.
I fly mainly fly at the Millingtonbarnstormers. But sometimes on Monday or Tuesdays, I will hook up with the 3D guys at propbusters in the afternoon and fly over there. I will gladly let you fly it and see what you think.
I really like the way the plane flys. It flys real light. So far in my opinion, the plane could either use to loose some weight or needs more power.
Like I said earlier, I have been flying a sub 4.5lbs airplane with a YS63 on it. so I am use to really, really, good vertical.
04-11-2004, 09:48 PM
#236
Senior Member
Join Date: Jul 2003
Location: Buffalo,
NY
Posts: 441
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
I here you m.gramling on the size and weight diff, i've got a 3.75 profile with a mouse can pipe 46fx that can do a 5 foot loop while excelerating and if you don't throttle down the tail would probably rip off in 3 seconds, vertical is like an estes rocket, i thinks takeoff rollout is about 1 foot. this yak is going to be a change but i'm stoked about on the deck TRing this sucker, the KE hovering story got me goin cant wait, mines ready for covering now, one week aint bad i got it at the Toledo show, Mike P is a Cool Cat, happy to support a company that is so into what they do.
BTW anybody get the feeling while building the FUSE that they were building a surfboard? i did
Pics to come, i made a bunch of small changes, nothin major just personal prefs, painted my crazzy legs today, black rustolium
Hey how do you get the cool thumbnails on here, i've been trying to figure that out?...........i feel stupid posting huge pics and pissin off the dialup people.
BTW anybody get the feeling while building the FUSE that they were building a surfboard? i did
Pics to come, i made a bunch of small changes, nothin major just personal prefs, painted my crazzy legs today, black rustolium
Hey how do you get the cool thumbnails on here, i've been trying to figure that out?...........i feel stupid posting huge pics and pissin off the dialup people.
04-11-2004, 09:54 PM
#237
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Well, that's what that thrust calculator says so it must be right!
We all know real-world is something different. I don't believe for a minute that I'm actually getting 15lbs of thrust out of the engine, but I was just making the point that the Magnum had enough poop to pull this plane pretty good. Still running a little rich, I'm turning 10000 with the APC 15x4. I'm happy with the power so far!
We all know real-world is something different. I don't believe for a minute that I'm actually getting 15lbs of thrust out of the engine, but I was just making the point that the Magnum had enough poop to pull this plane pretty good. Still running a little rich, I'm turning 10000 with the APC 15x4. I'm happy with the power so far!
04-12-2004, 08:01 AM
#239
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Wow,
That shows me how bad the estimation of thrust is in those thrust calculators! The one I use, [link=http://www.lcrcc.net/thrust_calc.htm]LCRC Thrust Calculator[/link] says that that prop and RPM gives over 20 lbs of thrust.
Ok, so I know I'm getting over 7.5lbs, but surely less than what you're getting with the YS.
That shows me how bad the estimation of thrust is in those thrust calculators! The one I use, [link=http://www.lcrcc.net/thrust_calc.htm]LCRC Thrust Calculator[/link] says that that prop and RPM gives over 20 lbs of thrust.
Ok, so I know I'm getting over 7.5lbs, but surely less than what you're getting with the YS.
04-12-2004, 08:06 AM
#240
Senior Member
My Feedback: (2)
Join Date: Jan 2002
Location: Crest Hill,
IL
Posts: 429
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
I flew mine for the first time on Friday. Flew great. There was about a 20mph wind. I wasn't ready for it to take off in 2ft. I have a ST-90 on mine. I was worried it wouldn't have been enough power, but it was plenty. It hovered between 1/4 and 1/2 throttle. Knife edge harriers great.
04-12-2004, 10:21 AM
#241
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Beautiful job there, ckoerner! Did you have any trouble getting the plane down in that wind? I'm still trying to find the proper landing approach. The thing just doesn't want to quit flying!
04-12-2004, 10:27 AM
#242
Senior Member
My Feedback: (2)
Join Date: Jan 2002
Location: Crest Hill,
IL
Posts: 429
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Joebob,
Yes I did have trouble getting it to land. The second time I made it. I was at about 0 ground speed. Everyone thought I was going to stall it. When I was taxing back, it lifted off on me.
Yes I did have trouble getting it to land. The second time I made it. I was at about 0 ground speed. Everyone thought I was going to stall it. When I was taxing back, it lifted off on me.
04-12-2004, 07:04 PM
#244
Senior Member
My Feedback: (3)
Join Date: Nov 2003
Location: Lakeland,
FL
Posts: 449
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
I have found that the best way to get the OMP planes down in wind is to not completely cut the throttle and not try to slow them up so much that they just sit there in the air waiting to stall. I bring them in with a little power and pull the nose up to loose airspeed. It is a balance between the right amount of angle of attack and throttle. The amount of wind determins the angle of attack. you need to use rudder to maintain straight flight. As you find the right angle of attack that allows the plane to settle in ease up on the throttle. Touch the tail first and then gently lay it down on the the mains.
Ok, you can stop shouting, Yes this is a harrier landing. They work in the wind.
Ok, you can stop shouting, Yes this is a harrier landing. They work in the wind.
05-15-2004, 09:31 AM
#246
Senior Member
My Feedback: (-1)
Join Date: Aug 2003
Location: Lewiston,
ID
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
Do you guys think a Hitec HS-55 Micro servo would be alright for the throttle? It has 16oz/in. I'm going to use a YS 91 and want to keep the weight down on the front.
05-15-2004, 01:07 PM
#247
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
How much does the YS weigh? I'm using a Magnum .91XLs at 24.5oz, mounted about 1/4" from the front, Futaba 148 serov for throttle, battery in LE of wing, and it balances right at the rear of the range. You may not need to worry that much about it. If you want to go small, maybe the HS81. I'd worry about the 55 with that much vibration.
05-15-2004, 01:41 PM
#248
Senior Member
My Feedback: (-1)
Join Date: Aug 2003
Location: Lewiston,
ID
Posts: 246
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
I think the YS is around 26-28 oz. Since this post I stripped out an HS-81 that I've been using for the throttle on a Spad. Kind of answers my question regarding the HS-55! I noticed they make a metal gear HS-81, that may be the way to go. Maybe I should just stick with a standard servo, but this is my first build, and I'm paranoid that the plane is going to come out at 8 lbs. or so! No reason to believe that yet, just all in my head.
05-15-2004, 02:12 PM
#249
My Feedback: (14)
Join Date: Aug 2002
Location: Crestview, FL
Posts: 759
Likes: 0
Received 0 Likes
on
0 Posts
RE: OMP Yak build
The one you see in my avatar weighs 7lbs 4oz. Unless you really go crazy on the glue, you should be able to keep it under 7.5lbs. When you sheet the fuse, just be sure to use a very light coat of glue and plenty of pressure. I used maybe 1oz of Gorilla glue on the whole fuse.
Honestly though, even at 8lbs, I think this plane would fly just fine. It's so much of a floater as it is, a few more oz won't hurt it in the least. Now if we could just get rid of this blasted wind, I could fly mine a lot more. Been blowing between 10-20mph constantly for the last two months. Very uncharacteristic for this area this time of year. Thank goodness I just got Aerofly Pro or I'd going through withdrawl right now!
Honestly though, even at 8lbs, I think this plane would fly just fine. It's so much of a floater as it is, a few more oz won't hurt it in the least. Now if we could just get rid of this blasted wind, I could fly mine a lot more. Been blowing between 10-20mph constantly for the last two months. Very uncharacteristic for this area this time of year. Thank goodness I just got Aerofly Pro or I'd going through withdrawl right now!
