Tri cycle conversion to tail dragger question??
05-30-2008 | 06:44 AM
#1
Thread Starter
Member
Joined: Feb 2008
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
From: Co. Offaly, IRELAND
Tri cycle conversion to tail dragger question??
Rebuilding my crashed trainer. Do you have to move the main landing gear if converting a tri cycle trainer to a tail dragger and is it worth it ?
05-30-2008 | 07:01 AM
#2
My Feedback: (7)
Joined: Feb 2002
Posts: 2,051
Likes: 0
Received 0 Likes
on
0 Posts
From: Keller, TX
RE: Tri cycle conversion to tail dragger question??
Yes, the main gear (which are mounted aft of the balance point for tricycle arrangement) need to be moved forward, so that the axles are in line with the wing leading edge when the plane is level. Is it worth it? I think it is. 
05-30-2008 | 08:06 AM
#3
My Feedback: (1)
RE: Tri cycle conversion to tail dragger question??
Also, when converting to tail dragger, make sure your gear mount in the fuselage both in front of the wing and at the tail is satisfactory for the load it will be getting. For the tail wheel setup, remove the covering, clean the area, cut a piece of ply, 1/8 minimum, in the shape of the area where you are going to mount the tail wheel assembly, and CA or epoxy it in place.
In front of the wing, make a length of hardwood or thick ply, and epoxy it in place. Make sure you install braces to formers to secure it and keep it strong. Then you can either install blind nuts or drill/tap the hardwood, apply CA to the threads, and mount your landing gear using nylon bolts. The nylon bolts will give you a breaking point that will save the fuselage in case of a very hard landing. The bolts will shear off instead of tearing out the bottom of the fuselage.
CGr.
In front of the wing, make a length of hardwood or thick ply, and epoxy it in place. Make sure you install braces to formers to secure it and keep it strong. Then you can either install blind nuts or drill/tap the hardwood, apply CA to the threads, and mount your landing gear using nylon bolts. The nylon bolts will give you a breaking point that will save the fuselage in case of a very hard landing. The bolts will shear off instead of tearing out the bottom of the fuselage.
CGr.
05-30-2008 | 08:06 AM
#4
RE: Tri cycle conversion to tail dragger question??
yup , it`s worth it , especailly if you fly off grass . Tail draggers tend to handle wind better when taxing .
Install your landing gear like Jim suggested , you`ll be good to go .
Install your landing gear like Jim suggested , you`ll be good to go .
05-30-2008 | 08:09 AM
#6
RE: Tri cycle conversion to tail dragger question??
ORIGINAL: Insanemoondoggie
yup , it`s worth it , especailly if you fly off grass . Tail draggers tend to handle wind better when taxing .
Install your landing gear like Jim suggested , you`ll be good to go .
yup , it`s worth it , especailly if you fly off grass . Tail draggers tend to handle wind better when taxing .
Install your landing gear like Jim suggested , you`ll be good to go .
05-30-2008 | 08:15 AM
#8
RE: Tri cycle conversion to tail dragger question??
Hi Dick , I`ve been lurking in the background , following along . It`s been a rough year for me flying , so I`ve been humbled . LOL
But I have`nt crashed in a month , so things are looking up.
But I have`nt crashed in a month , so things are looking up.
05-30-2008 | 09:09 AM
#9
Thread Starter
Member
Joined: Feb 2008
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
From: Co. Offaly, IRELAND
RE: Tri cycle conversion to tail dragger question??
Thanks for all the advice. one last thing do i leave the tail wheel floating or do I have to fix it to the rudder. Alot more work to fix it to the rudder as the elevator is one piece across the ruder.
05-30-2008 | 09:16 AM
#10
Joined: Aug 2007
Posts: 1,610
Likes: 0
Received 0 Likes
on
0 Posts
From: Pittsfield,
MA
RE: Tri cycle conversion to tail dragger question??
It is OK to leave it free floating as the rudder will control the turning. I personally don't like the loose motion of it. You can also use the pull-pull tailwheel assemblies such as these:
http://www3.towerhobbies.com/cgi-bin...?&I=LXCLK9&P=7
http://www3.towerhobbies.com/cgi-bin...?&I=LXBN38&P=7
http://www3.towerhobbies.com/cgi-bin...?&I=LXCLK9&P=7
http://www3.towerhobbies.com/cgi-bin...?&I=LXBN38&P=7
05-30-2008 | 09:25 AM
#11
Senior Member
RE: Tri cycle conversion to tail dragger question??
If flying odd grass, you can often get by with just a tail skid instead of a tail wheel. You just have to use the elevator a little more carefully while taxing as you use a little bit of down elevator with a quick burst of power to lift the tail and blow it around for sharp turns; to much elevator and you nose over-to little and it won't turn. If mounting the main gear on the fuselage ahead of the wing, you may need to sweep the gear legs aft as, if the main gear is to far ahead of the CG takeoffs will be difficult and landings will be very bouncy.
05-30-2008 | 09:27 AM
#12
Joined: Jan 2003
Posts: 966
Likes: 0
Received 0 Likes
on
0 Posts
From: Sarnia, ON, CANADA
RE: Tri cycle conversion to tail dragger question??
Do you HAVE to mount the Tail wheel to the rudder? - No. Castering will work.
BUT! [X(]
You will have limited ground handling capability... IF it is possible, connecting the rudder to the tail wheel is highly recommended.
BTW- if this is your first Aircraft (trainer) you will have to relearn take offs - tail dragers handle differently than tricycle gears.
BUT! [X(]
You will have limited ground handling capability... IF it is possible, connecting the rudder to the tail wheel is highly recommended.
BTW- if this is your first Aircraft (trainer) you will have to relearn take offs - tail dragers handle differently than tricycle gears.
05-30-2008 | 10:18 AM
#13
Thread Starter
Member
Joined: Feb 2008
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
From: Co. Offaly, IRELAND
RE: Tri cycle conversion to tail dragger question??
Thanks lads for the advice but as I said the elevator is one piece across the rudder and to mount the tail wheel on the rudder I would have to cut the elevator in two. Is it worth the work.
05-30-2008 | 11:05 AM
#14
Joined: Aug 2007
Posts: 1,610
Likes: 0
Received 0 Likes
on
0 Posts
From: Pittsfield,
MA
RE: Tri cycle conversion to tail dragger question??
ORIGINAL: dmurf
Thanks lads for the advice but as I said the elevator is one piece across the rudder and to mount the tail wheel on the rudder I would have to cut the elevator in two. Is it worth the work.
Thanks lads for the advice but as I said the elevator is one piece across the rudder and to mount the tail wheel on the rudder I would have to cut the elevator in two. Is it worth the work.
http://www3.towerhobbies.com/cgi-bin...?&I=LXCLK9&P=7
http://www3.towerhobbies.com/cgi-bin...?&I=LXBN38&P=7
All you would need to do is:
1) Move the main landing gear to approximately where the leading edge of the wing is. To do this you epoxy 1/4" thick ply inside the fuselage as the base for the landing gear, drill the mounting holes and use blind nuts inside the fuselage to hold the bolts.
2) Assemble the tail wheel assembly shown above.
3) Adjust the CG balance
4) Learn the difference in ground handling.
05-30-2008 | 12:01 PM
#15
RE: Tri cycle conversion to tail dragger question??
http://www.rcuniverse.com/forum/m_21..._2/key_/tm.htm
http://www.rcuniverse.com/forum/m_7402702/tm.htm
If you look at the pictures I posted in this thread, it shows where the pushrod comes out, and other things to help. You mount the pushrod to the rudder servo, on the opposite side from the rudder. I didn't use a sleeve, I just put a Z bend on the end of the rod that attaches to the tailwheel, and an adjustable clevis on the threaded end of the rod at the servo end for adjustment.
http://www.rcuniverse.com/forum/m_7402702/tm.htm
If you look at the pictures I posted in this thread, it shows where the pushrod comes out, and other things to help. You mount the pushrod to the rudder servo, on the opposite side from the rudder. I didn't use a sleeve, I just put a Z bend on the end of the rod that attaches to the tailwheel, and an adjustable clevis on the threaded end of the rod at the servo end for adjustment.
05-30-2008 | 07:45 PM
#16
My Feedback: (16)
RE: Tri cycle conversion to tail dragger question??
I did a LT40 into a tail dragger this past fall.
Used a Dubro tail wheel bracket with a new wire going up into the rudder
Used plywood reinforcement as mentioned previously.
Has Aluminum gear from a H9 Super Stick 60 retained with nylon bolts tapped directly into the 1/4" plywood doubler I added inside behind F-2.
I converted the wing to bolt on with dowels in the front and nylon bolts in the rear.
Used a Dubro tail wheel bracket with a new wire going up into the rudder
Used plywood reinforcement as mentioned previously.
Has Aluminum gear from a H9 Super Stick 60 retained with nylon bolts tapped directly into the 1/4" plywood doubler I added inside behind F-2.
I converted the wing to bolt on with dowels in the front and nylon bolts in the rear.
05-30-2008 | 09:36 PM
#17
RE: Tri cycle conversion to tail dragger question??
ORIGINAL: dmurf
Thanks lads for the advice but as I said the elevator is one piece across the rudder and to mount the tail wheel on the rudder I would have to cut the elevator in two. Is it worth the work.
Thanks lads for the advice but as I said the elevator is one piece across the rudder and to mount the tail wheel on the rudder I would have to cut the elevator in two. Is it worth the work.
05-31-2008 | 10:04 AM
#18
Senior Member
Joined: Oct 2005
Posts: 254
Likes: 0
Received 0 Likes
on
0 Posts
From: simi valley, CA
RE: Tri cycle conversion to tail dragger question??
Here are 2 insights about tail dragger gear placement and rudder size.
Placing main gear under the wing leading edge is not exactly the right answer. Forward placement prevents nosing over but the plane will want to swing around (ground loop) when it swerves on the runway or porpoise when you don’t touch down softly. Moving the mains back stops those problems but makes it easier to nose over. The way to fix all those problems is push the mains back behind the CG then add a nose wheel. A good tail dragger thumb rule is to locate the mains where the pane will balance on the mains when the fuselage is tilted about 20 degrees nose down.
Tricycle gear track straight naturally and don’t need much help from the rudder to steer straight down the runway, so trainer types typically have tricycle gear and rather small rudders. When trainer types are converted to tail draggers they often could use a bigger rudder.
There is no one exact right answer for conversion. It is a matter of preference. When you fly your conversion, here is how to evaluate it. If you find your plane tends to ground loop or porpoise annoyingly during landings, then your mains are too far forward. If you find your plane tends to nose over too easily, then your mains are too far back. And last, if you just can’t find a happy medium then your rudder authority is probably insufficient.
Experimenting is all part of the fun. Hope that helps.
Placing main gear under the wing leading edge is not exactly the right answer. Forward placement prevents nosing over but the plane will want to swing around (ground loop) when it swerves on the runway or porpoise when you don’t touch down softly. Moving the mains back stops those problems but makes it easier to nose over. The way to fix all those problems is push the mains back behind the CG then add a nose wheel. A good tail dragger thumb rule is to locate the mains where the pane will balance on the mains when the fuselage is tilted about 20 degrees nose down.
Tricycle gear track straight naturally and don’t need much help from the rudder to steer straight down the runway, so trainer types typically have tricycle gear and rather small rudders. When trainer types are converted to tail draggers they often could use a bigger rudder.
There is no one exact right answer for conversion. It is a matter of preference. When you fly your conversion, here is how to evaluate it. If you find your plane tends to ground loop or porpoise annoyingly during landings, then your mains are too far forward. If you find your plane tends to nose over too easily, then your mains are too far back. And last, if you just can’t find a happy medium then your rudder authority is probably insufficient.
Experimenting is all part of the fun. Hope that helps.
05-31-2008 | 11:39 AM
#19
Senior Member
Joined: Feb 2004
Posts: 262
Likes: 0
Received 0 Likes
on
0 Posts
From: Mississauga,
ON, CANADA
RE: Tri cycle conversion to tail dragger question??
ORIGINAL: multiflyer
Here are 2 insights about tail dragger gear placement and rudder size.
Placing main gear under the wing leading edge is not exactly the right answer. Forward placement prevents nosing over but the plane will want to swing around (ground loop) when it swerves on the runway or porpoise when you don’t touch down softly. Moving the mains back stops those problems but makes it easier to nose over. The way to fix all those problems is push the mains back behind the CG then add a nose wheel. A good tail dragger thumb rule is to locate the mains where the pane will balance on the mains when the fuselage is tilted about 20 degrees nose down.
Tricycle gear track straight naturally and don’t need much help from the rudder to steer straight down the runway, so trainer types typically have tricycle gear and rather small rudders. When trainer types are converted to tail draggers they often could use a bigger rudder.
There is no one exact right answer for conversion. It is a matter of preference. When you fly your conversion, here is how to evaluate it. If you find your plane tends to ground loop or porpoise annoyingly during landings, then your mains are too far forward. If you find your plane tends to nose over too easily, then your mains are too far back. And last, if you just can’t find a happy medium then your rudder authority is probably insufficient.
Experimenting is all part of the fun. Hope that helps.
Here are 2 insights about tail dragger gear placement and rudder size.
Placing main gear under the wing leading edge is not exactly the right answer. Forward placement prevents nosing over but the plane will want to swing around (ground loop) when it swerves on the runway or porpoise when you don’t touch down softly. Moving the mains back stops those problems but makes it easier to nose over. The way to fix all those problems is push the mains back behind the CG then add a nose wheel. A good tail dragger thumb rule is to locate the mains where the pane will balance on the mains when the fuselage is tilted about 20 degrees nose down.
Tricycle gear track straight naturally and don’t need much help from the rudder to steer straight down the runway, so trainer types typically have tricycle gear and rather small rudders. When trainer types are converted to tail draggers they often could use a bigger rudder.
There is no one exact right answer for conversion. It is a matter of preference. When you fly your conversion, here is how to evaluate it. If you find your plane tends to ground loop or porpoise annoyingly during landings, then your mains are too far forward. If you find your plane tends to nose over too easily, then your mains are too far back. And last, if you just can’t find a happy medium then your rudder authority is probably insufficient.
Experimenting is all part of the fun. Hope that helps.
I did a tail dragger conversion on an old trainer, as part of that I extended the rudder about 75%. I also extended the elevators, and took all the dihedral out of the wing. Flies great!
05-31-2008 | 06:54 PM
#21
My Feedback: (16)
RE: Tri cycle conversion to tail dragger question??
I've had the LT40 since the ARF version first came out. 10 years ago anyway. It used to have a Tower 46 and a nose wheel but I quit flying it in 2001 because I didn't like nose wheels and it was terrible on the ground in the grass and on windy days. I fly from grass fields.
I just started flying it again this spring as a tail dragger and it is great. It flies a lot like a Cub. It floats a long ways and you can get into trouble with the float on a gusty day. I just touch it down on the main wheels first and glue it on during the gusty days. It reminds me of my Robin Hood 80 and the Telemaster 40's that I've seen others fly.
With the nose wheel it would nose over on one front quarter easily if the wind got behind it. The nose wheel mechanism was a consistent maintenance situation before. There seems to be less drag in the grass as a tail dragger.
I also like the bolt on wings that it now has.
I have noticed with that big wing and the dihedral that if you have a crosswind takeoff, the wind can get under the upwind wing at lift off and cause trouble unless you hold it on the ground until the speed builds up a little more than what it takes to lift off.
I just started flying it again this spring as a tail dragger and it is great. It flies a lot like a Cub. It floats a long ways and you can get into trouble with the float on a gusty day. I just touch it down on the main wheels first and glue it on during the gusty days. It reminds me of my Robin Hood 80 and the Telemaster 40's that I've seen others fly.
With the nose wheel it would nose over on one front quarter easily if the wind got behind it. The nose wheel mechanism was a consistent maintenance situation before. There seems to be less drag in the grass as a tail dragger.
I also like the bolt on wings that it now has.
I have noticed with that big wing and the dihedral that if you have a crosswind takeoff, the wind can get under the upwind wing at lift off and cause trouble unless you hold it on the ground until the speed builds up a little more than what it takes to lift off.
