AKM SU-27 Flanker-Does Look Good
#251
RE: AKM SU-27 Flanker-Does Look Good
Before closing up the bottom of the fake jet engine nacells run one of those thin plastic antenna tubes from front to back. be sure to run it through the lightening holes in the "F" formers so it will not contact the spar. I do not know if that spar thing was really the problem... but it would not hurt to keep it away from the aluminum spar!
Rich
Rich
#253
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RE: AKM SU-27 Flanker-Does Look Good
Hey Rich, you have one nice looking Sukhoi!
Pardon me for taking this off topic, but you mentioned that you recommend 3/16" wire for the landing gear. Do you or anyone else know of a source to buy them with the coils already in them? All I can find are 5/32", and I'm struggling with a spongy nose gear as well.[:@]
I've tried coiling my own, but the results aren't pretty.
Pardon me for taking this off topic, but you mentioned that you recommend 3/16" wire for the landing gear. Do you or anyone else know of a source to buy them with the coils already in them? All I can find are 5/32", and I'm struggling with a spongy nose gear as well.[:@]
I've tried coiling my own, but the results aren't pretty.
#255
RE: AKM SU-27 Flanker-Does Look Good
i got mine at sheldons, but they do not cary them anymore. http://www.retracts.com/ is the spring air site! Alex at AKM has them i think!
Rich
Rich
#258
RE: AKM SU-27 Flanker-Does Look Good
This is the first of several posts I plan to put up for everyone who is building the AKM SU-27 Flanker. I have had 4 very successful flights now with little to no problems. The following posts are what I think are enhancements or improvements to an already fantastic plane!
The first photo is a picture of the plan where I added a third rudder hinge to my plane. The hinge is in RED. All surfaces in high speed applications are subject to "aerodynamic flutter" which can result in catastrophic failure and loss of the entire aircraft. The Jett Engine I used is a great match for this plane but will also increase many of the loads imposed on your plane and increase the risk of flutter. I have had some flutter in the SU-27 rudders but they were strong enough to withstand the pounding. I also used a "TOE IN" (see picture #3) technique on both the rudders to put a constant load on them... it seems to help reduce flutter. Picture #4 is an early picture of a piece of tri-stock I added to the rudder before gluing it on to the fuselage... I think it makes it A LOT STRONGER!! It at least tripled the surface area where it is glued to the inside lower skin.
Photo #2 is a photo of the plan which shows a piece of tri-stock (SHOWN IN RED) I added to increase the gluing area of the landing gear block. It makes the gear block strong especially if you are flying off of a grass strip!
The first photo is a picture of the plan where I added a third rudder hinge to my plane. The hinge is in RED. All surfaces in high speed applications are subject to "aerodynamic flutter" which can result in catastrophic failure and loss of the entire aircraft. The Jett Engine I used is a great match for this plane but will also increase many of the loads imposed on your plane and increase the risk of flutter. I have had some flutter in the SU-27 rudders but they were strong enough to withstand the pounding. I also used a "TOE IN" (see picture #3) technique on both the rudders to put a constant load on them... it seems to help reduce flutter. Picture #4 is an early picture of a piece of tri-stock I added to the rudder before gluing it on to the fuselage... I think it makes it A LOT STRONGER!! It at least tripled the surface area where it is glued to the inside lower skin.
Photo #2 is a photo of the plan which shows a piece of tri-stock (SHOWN IN RED) I added to increase the gluing area of the landing gear block. It makes the gear block strong especially if you are flying off of a grass strip!
#259
RE: AKM SU-27 Flanker-Does Look Good
Here is one last picture I took of the tri-stock I used to reinforce the retract plates! As you can see it greatly increases the surface area in which to glue the retract plate into place!
I will post more info soon!
Rich
I will post more info soon!
Rich
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RE: AKM SU-27 Flanker-Does Look Good
Rich, I'd like to say thanks for sharing the information , I too am about start my akm flanker build , this sort of input is pure gold..thanks to everyone who has shared information to help others build a successful kit, I havent built a kit in a long time , so I am greatful for all the tips!!!
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RE: AKM SU-27 Flanker-Does Look Good
Hi Rich!
Thank you for your input as stated above it is very valuable to all and helps with a more successfully flight for ever one including me. My input to your ideas are:
1) I am and have sealed ALL my control surfaces gaps including rudders to increase efficiency and help to stop or reduce flutter.
2) I too put 1/2" tri both top and bottom of the rudder fins for more strength.
3) Instead of drilling out the hole to clear the head of the wing hold down bolt in the retract plate , I only drilled large enough for the thread part to pass through in order to let the head of the bolt Clamp the retract plate to the rest of the wing.
4) The three other mods I have done just to see if they work or not, are to extend each wing tip by 3" with out the missiles rails, increase the surface area of the elevators and made my own hatch covers to replace the plastics ones.
I am planning to use Flaperons latter in the test flights as well.
Thank you for your input as stated above it is very valuable to all and helps with a more successfully flight for ever one including me. My input to your ideas are:
1) I am and have sealed ALL my control surfaces gaps including rudders to increase efficiency and help to stop or reduce flutter.
2) I too put 1/2" tri both top and bottom of the rudder fins for more strength.
3) Instead of drilling out the hole to clear the head of the wing hold down bolt in the retract plate , I only drilled large enough for the thread part to pass through in order to let the head of the bolt Clamp the retract plate to the rest of the wing.
4) The three other mods I have done just to see if they work or not, are to extend each wing tip by 3" with out the missiles rails, increase the surface area of the elevators and made my own hatch covers to replace the plastics ones.
I am planning to use Flaperons latter in the test flights as well.
#264
RE: AKM SU-27 Flanker-Does Look Good
I have the link for my SU-27 video compliments of bob27s. Email me for the link! [email protected]
rich
rich
#265
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RE: AKM SU-27 Flanker-Does Look Good
ORIGINAL: Blade47
Here is a picture of my ALL most finished SU ..... come on Don .... how about a pic of your MIG29
Here is a picture of my ALL most finished SU ..... come on Don .... how about a pic of your MIG29
Don
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RE: AKM SU-27 Flanker-Does Look Good
ORIGINAL: jetpilotrich
I have the link for my SU-27 video compliments of bob27s. Email me for the link! [email protected]
rich
I have the link for my SU-27 video compliments of bob27s. Email me for the link! [email protected]
rich
Very nice vid, and a very nice looking Su-27 too. I hope I can get mine to look as good as yours.
And the Jett sounds awesome too... that really makes me consider putting down the cash for a 90L after all, instead of going for some nameless Chinese copy
What prop are you using there? Looks like it's moving at a good pace...
I guess this proves that the Sukhoi is a good flying plane, in spite of all the doubts raised here about the CG and stuff...
Are you having problems with your rudders? What's up?
Oh yeah, one more question: how does the plane look on the bottom after a flight? I'm wondering about oil ending up in the wheel wells [:'(]
Does the exhaust diverter work well? And how do you keep it on there?
Boy... a lot of questions... [X(]
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RE: AKM SU-27 Flanker-Does Look Good
excellent video, awesome jet, awesome engine, looks like it moves ok too..and no, you dont blink with one of these..someone told me this is not a speed plane, looks pretty fast to me..now all thats left is to open that box of wood and get it all together!!!
TOTALLY AWESOME
YOU GOTTA LOVE THAT SUEDO AFTER BURNER GLOW. nice touch
TOTALLY AWESOME
YOU GOTTA LOVE THAT SUEDO AFTER BURNER GLOW. nice touch
#269
RE: AKM SU-27 Flanker-Does Look Good
The plane is very stable in all phases of flight and lands at very normal speeds!
The prop I am using is a regular old APC 12-6. You cant beat the Jett... they haul A@# and are easy to adjust... This is my second Jett .90L and they both run flawlessly. My motto is: "you can buy a cheaper engine.. but not a better one" After buying another brand of engine plus header, pipe and brackets you are around the same price as a Jett and the Jett is out of the box tuned power!! No need to screw around with tuning the pipe!
Here is a critical measurement from Alex at AKM: If you measure from FRONT of F6 to outside front hole of the retract it should measure 95mm. Ignore what the plan says in this regard and ignore the CG on the plan.... it will not work unless you move the gear way back. If you have mounted the gear using the previous measurement your main gear will be right on. This was the first time I did not use a balancer!!! Then when you balance the plane do it on pavement or other hard surface.... it should sit on all 3 gears BARELY!! When you lift the nose in the air about an inch the tail should fall to the ground (dont scratch up your plane!). Remember this is with an empty tank.... once you add gas the nose will be solid on the ground. Use at least an 18oz tank. The Jett uses it fast and you want to land with a a few oz. in there!
I am getting some rudder flutter.... I am working on some solutions... the obvious one is to go slower... but that kinda sucks... for now I have put the toe in on the rudders... you can see a pic I put up several posts ago. the inward deflection of the rudders seems to help abit. Also I just added another epoxy bearing to the rudder torque rod to get rid of some of the play... I attached a pic! also use 3 hinges not 2!
The oil is a bain in the A@# as usual! The diverter helps. I doped my wheel wells before covering the plane.... but they do not seem to get alot of oil in them. the bottom of the plane does get real messy.... no way to avoid that. The fake black ultracote jet intake is somewhat fuel proof because I covered it with clear covering to keep the black part from coming off!
L8tr
Rich
The prop I am using is a regular old APC 12-6. You cant beat the Jett... they haul A@# and are easy to adjust... This is my second Jett .90L and they both run flawlessly. My motto is: "you can buy a cheaper engine.. but not a better one" After buying another brand of engine plus header, pipe and brackets you are around the same price as a Jett and the Jett is out of the box tuned power!! No need to screw around with tuning the pipe!
Here is a critical measurement from Alex at AKM: If you measure from FRONT of F6 to outside front hole of the retract it should measure 95mm. Ignore what the plan says in this regard and ignore the CG on the plan.... it will not work unless you move the gear way back. If you have mounted the gear using the previous measurement your main gear will be right on. This was the first time I did not use a balancer!!! Then when you balance the plane do it on pavement or other hard surface.... it should sit on all 3 gears BARELY!! When you lift the nose in the air about an inch the tail should fall to the ground (dont scratch up your plane!). Remember this is with an empty tank.... once you add gas the nose will be solid on the ground. Use at least an 18oz tank. The Jett uses it fast and you want to land with a a few oz. in there!
I am getting some rudder flutter.... I am working on some solutions... the obvious one is to go slower... but that kinda sucks... for now I have put the toe in on the rudders... you can see a pic I put up several posts ago. the inward deflection of the rudders seems to help abit. Also I just added another epoxy bearing to the rudder torque rod to get rid of some of the play... I attached a pic! also use 3 hinges not 2!
The oil is a bain in the A@# as usual! The diverter helps. I doped my wheel wells before covering the plane.... but they do not seem to get alot of oil in them. the bottom of the plane does get real messy.... no way to avoid that. The fake black ultracote jet intake is somewhat fuel proof because I covered it with clear covering to keep the black part from coming off!
L8tr
Rich
#270
RE: AKM SU-27 Flanker-Does Look Good
For Blade47
Your #3 suggestion.... the wing bolt should go down through the top of the fuselage..... It sounds like you may have put it up through the bottom. I sent a pic.... look on the top of the fuselage (blue part) for the holes!
Rich
Your #3 suggestion.... the wing bolt should go down through the top of the fuselage..... It sounds like you may have put it up through the bottom. I sent a pic.... look on the top of the fuselage (blue part) for the holes!
Rich
#271
RE: AKM SU-27 Flanker-Does Look Good
Blade47,
Be careful with the enlarged elevators.... if they are larger from the hinge point AFT they may tend to flutter easier! I was kind of amazed that the elevator throw that Alex uses on this plane worked..... He knows what he is doing and his throws work perfectly... I set mine up to have 2 1/8" throw (like the instructions say) from neutral to up AND 2 1/8" from neutral to down!! thats a total of 4 1/4 total elevator throw measured from the widest/inboard section. I have hade ZERO problems with all that throw and no EXPO of any kind in the STAB! There is plenty of elevator available in all phases of flight with this arrangement!
Rich
Be careful with the enlarged elevators.... if they are larger from the hinge point AFT they may tend to flutter easier! I was kind of amazed that the elevator throw that Alex uses on this plane worked..... He knows what he is doing and his throws work perfectly... I set mine up to have 2 1/8" throw (like the instructions say) from neutral to up AND 2 1/8" from neutral to down!! thats a total of 4 1/4 total elevator throw measured from the widest/inboard section. I have hade ZERO problems with all that throw and no EXPO of any kind in the STAB! There is plenty of elevator available in all phases of flight with this arrangement!
Rich
#272
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RE: AKM SU-27 Flanker-Does Look Good
ORIGINAL: jetpilotrich
For Blade47
Your #3 suggestion.... the wing bolt should go down through the top of the fuselage..... It sounds like you may have put it up through the bottom. I sent a pic.... look on the top of the fuselage (blue part) for the holes!
Rich
For Blade47
Your #3 suggestion.... the wing bolt should go down through the top of the fuselage..... It sounds like you may have put it up through the bottom. I sent a pic.... look on the top of the fuselage (blue part) for the holes!
Rich
Don
#273
RE: AKM SU-27 Flanker-Does Look Good
Im not sure! There are thick wing bolt blocks below the wing bolt plates which are intended to be tapped... that way the wing bolt plates are held tight against the wing bolt blocks. If you tapped the blocks, I would imagine if the screw protrudes far enough up through the wing bolt plate.... it should hold ok.... It just was not intended to be built that way. Probably will not have a problem with it!
Rich
Rich
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RE: AKM SU-27 Flanker-Does Look Good
Indeed Rich you are right about the wing bolt and having the hole in the top of the wing. But this is my own mod ...... My thinking on this is why do you have to have a hole in the top of the wing when it will have the same clamp force from the bottom and no hole in the top (?) besides with the retracts exposed to world under the wing a clear bolt head may go unnoticed my thinking anyway ..let me know what you think ..or others on this.
I did have to use a 1 1/2" bolt to make this work. If I get my retracts this weekend I will take a picture
Pete
I did have to use a 1 1/2" bolt to make this work. If I get my retracts this weekend I will take a picture
Pete
#275
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RE: AKM SU-27 Flanker-Does Look Good
ORIGINAL: Blade47
Indeed Rich you are right about the wing bolt and having the hole in the top of the wing. But this is my own mod ...... My thinking on this is why do you have to have a hole in the top of the wing when it will have the same clamp force from the bottom and no hole in the top (?) besides with the retracts exposed to world under the wing a clear bolt head may go unnoticed my thinking anyway ..let me know what you think ..or others on this.
I did have to use a 1 1/2" bolt to make this work. If I get my retracts this weekend I will take a picture
Pete
Indeed Rich you are right about the wing bolt and having the hole in the top of the wing. But this is my own mod ...... My thinking on this is why do you have to have a hole in the top of the wing when it will have the same clamp force from the bottom and no hole in the top (?) besides with the retracts exposed to world under the wing a clear bolt head may go unnoticed my thinking anyway ..let me know what you think ..or others on this.
I did have to use a 1 1/2" bolt to make this work. If I get my retracts this weekend I will take a picture
Pete
Don