Go Back  RCU Forums > RC Airplanes > Aerodynamics
Reload this Page >

Flyin King Takeoffs

Community
Search
Notices
Aerodynamics Discuss the physics of flight revolving around the aerodynamics and design of aircraft.

Flyin King Takeoffs

Thread Tools
 
Search this Thread
 
Old 08-27-2007, 09:22 PM
  #1  
thepope
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2001
Location: nestor falls, ON, CANADA
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Default Flyin King Takeoffs

I love my Flyin King but I have a heck of a time with it on takeoffs. I built it as a tail dragger as per the plans and have a Thunder Tiger 91 4 stroke in it. The throws are all as per instructions. It flies great once airborne but the takeoffs are a little on the wild side. It seems like the rudder doesn't have enough authority so I have increased the throws with not much if any difference. It is really hard to keep it going straight during the takeoff roll until it gets to flying speed. Landing is fairly normal but it does get hard to keep it going straight when it slows down a bit. Any suggestions??
Bill
Old 08-27-2007, 10:32 PM
  #2  
wvarn1957
My Feedback: (3)
 
wvarn1957's Avatar
 
Join Date: Jul 2002
Location: O\'fallon, MO
Posts: 245
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Try modifying the main gear to give about 2 to 3 deg of toe in. This usually helps keep a straight take off run.
Old 08-27-2007, 10:49 PM
  #3  
Rotaryphile
Senior Member
 
Join Date: Feb 2002
Location: Fredericton, NB, CANADA
Posts: 344
Likes: 0
Received 4 Likes on 3 Posts
Default RE: Flyin King Takeoffs

Many airplanes can have their overall handling greatly improved by increasing the rudder/fin area. Try taping on a temporary cardboard extension to the trailing edge of the rudder, and reduce rudder travel proportionally, if your rudder authority is already OK. If you like the results, you can permanently increase the rudder chord later. This little trick has worked wonders on several evil handling models.
Old 08-27-2007, 11:18 PM
  #4  
Campgems
Senior Member
 
Join Date: Feb 2006
Location: Arroyo Grande, CA
Posts: 4,465
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Flyin King Takeoffs

With your engine, you have a ton of torque. I've got a 4*60 with a Magnum 91 and if I punch it, off into the weeds it goes. However, if I slowly increase speed, it is a real ***** cat on the runway. As soon as I get lined up with the center line, I take my hand off the right stick ( I use full up elevator when taxing though) and slowly increase speed after about 30 to 40 ft, the tail starts to lift and at that point, I increase speed a bit faster then grab some elevator and I'm up. A couple times, I neglected to let loose of the elevator when I started my roll out and I was airborne a lot sooner than I wanted to be.

I have a Quicke 500, one of the orginal ones, and I put an aluminum landing gear on it with wheel pants. It was really iffy if I could get it down the runway. I even had a couple of the instructors give it a go and they had trouble. One day, there was just the two of us at the field and my instructor told me go out on the runway and hold the tail untill he signaled to let it go. He wound it up to full throttle and had me let go. It imeaditaly did a U turn and came right back at me. We killed the engine and as I was carrying it back to the bench, I head something rattling. Turns out that there was a stone in the left wheel pant and some times, it would jam that wheel. I took off the pants and it handled quite civilized after.

Don
Old 08-27-2007, 11:39 PM
  #5  
pimmnz
 
Join Date: Nov 2005
Location: Auckland, NEW ZEALAND
Posts: 1,961
Likes: 0
Received 1 Like on 1 Post
Default RE: Flyin King Takeoffs

One other thing you might like to check is how far forward of the cg the wheel centres are. The further forward they are, the more likely the model will want to ground loop. If you can get them back to about an inch or so fwd of the cg it will make things easier. Get the tail up on takeoff as soon as possible, even if you have to use down elevator for a start as this will allow the rudder to have more effect, it won't have to drag the tailwheel/skid across the grass as well. Oh, and do make sure that both wheels spin on the axles reasonably freely, and about the same...
Evan, W.B.#12.
Old 08-28-2007, 08:07 AM
  #6  
Dsegal
Senior Member
 
Join Date: Oct 2002
Location: Philadelphia, PA
Posts: 2,065
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

You have received some good advice here. As someone who is clumsy with the left stick here is what I suggest in addition. Go the field when there are not a lot of people around. Place the plane on the centerline of the runway and stand right behind it. Use the gentle throttle and other techniques mentioned and slowly go down the runway. Concentrate on the position of the fuselage and start to correct with the rudder as soon as you sense misalignment. You must stay on top of the situation. If it yaws wide once immediately shut down and start over. Once the zig-zags start it won't get any better. It just takes practice and well set up landing gear.
Old 08-28-2007, 09:06 PM
  #7  
thepope
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2001
Location: nestor falls, ON, CANADA
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Thanks for the help guys. I give it a liitle toe in so I'll see what that does. I forgot that I had moved the landing gear ahead about 3/4" ahead when I put it on floats so I'll try putting it back where it should be. I do seem to have better results when I give it full power rather than gradually applying power. I'll report back with the results.
Thanks again, Bill.
Old 08-29-2007, 06:16 AM
  #8  
da Rock
Senior Member
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,517
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Flyin King Takeoffs

Got a picture of a Flying King?

Converting a tricycle gear to a tail dragger does one thing for sure. It takes a tail that was designed to taxi and take off when already flying level and drops it down into whatever wing downwash happens to be back there. It's also starting out at an AOA that's probably way past the stall AOA.

So converted taildraggers lose the authority they had as tricycles. Until the tail comes up. Remember that the prop is flying and has good purchase on the air whenever the airplane is moving forward. But the tail doesn't have good purchase until it's flying, and it's not flying until it comes up. So if you jab the throttle before the tail comes up, the prop has already won the tug of war. So be very easy on moving the throttle until the tail is flying.

The ground handling of a taildragger can really be helped with toe in. Do the toe in with the airplane level however. That way, when the tail is down, the toe adds some camber. And it's the kind of camber that motorcycle riders use to turn. And each tire will be trying to turn in, instead of trying to turn out. Add that to the toe in's self straightening and you got a winning combination instead of a losing one.
Old 08-29-2007, 10:39 AM
  #9  
Rodney
Senior Member
 
Join Date: Dec 2001
Location: FL
Posts: 7,769
Likes: 0
Received 5 Likes on 5 Posts
Default RE: Flyin King Takeoffs

Most of your problem was probably caused by your moving the landing gear forward, a big NO-NO on tail draggers. The suggestion for toe in is also a good one. Once you get the hang of tail draggers, it is doubtfull you will ever want to go back to trike gear unless necessary for scale models.
Old 09-01-2007, 01:06 PM
  #10  
AERORICH73
 
Join Date: Apr 2006
Location: Scappoose, OR
Posts: 469
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Hi: I suggest contacting B.T.E. Engineering to get a perspective from the designer, Bruce, before making any control surface changes. He would give you the reason for the plane having problems maintaining tracking problems on takeoff. The toe-in suggestion is one of the normal adjustments made on taildraggers. I purchased a used King before building my kit that was constructed as a taildragger. In working over the plane, I change the gear to tricycle for better ground handling. Watched for many years other pilots flying taildraggers, and it just seems the takeoffs are short, crooked with a lot of weaving. It may be that I have never been at a club field that had seasoned taildragger pilots.

Have fun with your King.

Rich S.
Old 09-01-2007, 06:42 PM
  #11  
Gremlin Castle
My Feedback: (14)
 
Join Date: Feb 2004
Location: Arlington, TX
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs


ORIGINAL: AERORICH

Hi: I suggest contacting B.T.E. Engineering to get a perspective from the designer, Bruce, before making any control surface changes. He would give you the reason for the plane having problems maintaining tracking problems on takeoff. The toe-in suggestion is one of the normal adjustments made on taildraggers. I purchased a used King before building my kit that was constructed as a taildragger. In working over the plane, I change the gear to tricycle for better ground handling. Watched for many years other pilots flying taildraggers, and it just seems the takeoffs are short, crooked with a lot of weaving. It may be that I have never been at a club field that had seasoned taildragger pilots.

Have fun with your King.

Rich S.
I would have to agree with your last sentence. Tail draggers are the norm rather than the exception across the country.
Without being present it is hard to know how much of the problem is landing gear versus the pilot and his ability to use the left hand.
The Flying King is known for its honest and docile habits. If the landing gear is in its stock location the first thing to check is what another poster suggested, the toe in.
Old 09-02-2007, 12:06 PM
  #12  
gyrocptr
 
Join Date: Jul 2006
Location: Neenah, WI
Posts: 139
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Flyin King Takeoffs

I've been flying tail-draggers for over 30 years; here are few things that may help your take-offs.
Locate the main wheel axles between 0-1.5 inches ahead of the leading edge of the wing. The more the main wheels are moved toward the front of the plane, the less the tendency to nose-over, but the greater the tendency to ground loop.
Toe-out the wheels 2-3 degrees. Yes, toe-out. A plane behaves differently than a car. When the plane starts to ground loop, the trailing-wheel lifts away from the ground while the leading-wheel "digs" into the ground. If the leading-wheel is toed-in, it "steers" in the direction of the ground loop and makes it worse. Toe-out in the leading-wheel will "steer" opposite the direction of the ground loop and have a counteracting effect.
Lengthen the tail wheel until the plane sits on level-ground, with about 10 degrees nose-up attitude. The more-level the plane sits, the lower the tendency to ground loop, but you want to have 5-10 degrees of nose-up angle available to generate lift for take-off.
Use little or no caster in the tail wheel. Extend the tail wheel strut straight down from the pivot-bearing or rudder hinge-line. Use a tiny bit of caster in the aft-direction, just to make sure the tail strut doesn't slant forward. The straight-strut will reduce the sensitivity of tail-wheel steering.
Start your take-off run with full up-elevator control to keep the tail wheel pressed against the ground for steering. As the plane accelerates, gradually reduce the amount of up-elevator. With the plane moving, aero-steering with the rudder will become effective.
As much as possible, take-off directly into the wind. This is especially helpful with high-wing planes that have dihedral. A tail-dragger will try to weather-vane into the wind. Cross-wind take-offs are a bear!
Practice, practice, practice to develop the appropriate, control-reflexes.
Good luck!
Old 09-04-2007, 09:03 AM
  #13  
BruceTharpe
My Feedback: (1)
 
BruceTharpe's Avatar
 
Join Date: Nov 2003
Location: Rogue River, OR
Posts: 694
Likes: 0
Received 7 Likes on 4 Posts
Default RE: Flyin King Takeoffs

Received an email from Bill linking to this thread, so thought I should post my reply here. The BTE Flyin' King is a high-wing sport model that is designed for trike or taildragger gear as a builder's option. Both are shown clearly on the plans and instructions.

I will be the first to admit that a taildragger FK can be a challenge on the takeoff roll. But I would say the same thing for most high-wing taildraggers like Citabrias, Cubs, etc... If anything, I've always thought the FK rudder was extremely effective, to the point of being sensitive, so a light touch on the stick is required.

With no wind, you can pretty much expect the torque to pull you left so you need to be ready with right rudder. If you have a crosswind from the left side, you will need more right rudder, and if the crosswind is coming from the right side, you will need less right rudder, or even some left rudder. As the speed increases during the takeoff roll, you generally need less and less rudder input.

In general, a direct headwind and flying from grass makes taildragger takeoffs easier.

The toe-in vs. toe-out discussion has gone on for years. If one was the definitive solution, there would be no argument. I'm firmly in the middle - I like my wheels straight as can be and depend on my left thumb to keep the model pointed in the right direction.

My advice to Bill is to move the gear back to where it should be, and go light on the control inputs. Some expo on the rudder channel might make it less sensitive. And like an earlier poster stated, if things really get out of whack during a takeoff roll, just throttle back and try again.
Attached Thumbnails Click image for larger version

Name:	He96967.jpg
Views:	23
Size:	25.7 KB
ID:	756482  
Old 09-04-2007, 09:19 AM
  #14  
MajorTomski
 
MajorTomski's Avatar
 
Join Date: Apr 2003
Location: Oklahoma City, OK
Posts: 2,536
Likes: 0
Received 3 Likes on 3 Posts
Default RE: Flyin King Takeoffs

Well as long as we're fixing things here, it's P-factor not torque that causes an airplane to yaw to the left. It is physically impossible for torque to cause yaw.
Old 09-04-2007, 09:46 AM
  #15  
da Rock
Senior Member
 
Join Date: Oct 2005
Location: Near Pfafftown NC
Posts: 11,517
Likes: 0
Received 2 Likes on 2 Posts
Default RE: Flyin King Takeoffs

When you have an airplane that you think has a rudder that is extremely effective, to the point of being sensitive. And that makes takeoffs touchy, try setting and using your dual rates for the rudder.

Amazing what low rates can do for you.

And sometimes, changing how fast or slow the nosewheel/tailwheel steers, while leaving the rudder rigging alone, can do wonders.
Old 09-04-2007, 04:51 PM
  #16  
Gremlin Castle
My Feedback: (14)
 
Join Date: Feb 2004
Location: Arlington, TX
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs


ORIGINAL: gyrocptr

I've been flying tail-draggers for over 30 years; here are few things that may help your take-offs.
Locate the main wheel axles between 0-1.5 inches ahead of the leading edge of the wing. The more the main wheels are moved toward the front of the plane, the less the tendency to nose-over, but the greater the tendency to ground loop.
Toe-out the wheels 2-3 degrees. Yes, toe-out. A plane behaves differently than a car. When the plane starts to ground loop, the trailing-wheel lifts away from the ground while the leading-wheel "digs" into the ground. If the leading-wheel is toed-in, it "steers" in the direction of the ground loop and makes it worse. Toe-out in the leading-wheel will "steer" opposite the direction of the ground loop and have a counteracting effect.
Lengthen the tail wheel until the plane sits on level-ground, with about 10 degrees nose-up attitude. The more-level the plane sits, the lower the tendency to ground loop, but you want to have 5-10 degrees of nose-up angle available to generate lift for take-off.
Use little or no caster in the tail wheel. Extend the tail wheel strut straight down from the pivot-bearing or rudder hinge-line. Use a tiny bit of caster in the aft-direction, just to make sure the tail strut doesn't slant forward. The straight-strut will reduce the sensitivity of tail-wheel steering.
Start your take-off run with full up-elevator control to keep the tail wheel pressed against the ground for steering. As the plane accelerates, gradually reduce the amount of up-elevator. With the plane moving, aero-steering with the rudder will become effective.
As much as possible, take-off directly into the wind. This is especially helpful with high-wing planes that have dihedral. A tail-dragger will try to weather-vane into the wind. Cross-wind take-offs are a bear!
Practice, practice, practice to develop the appropriate, control-reflexes.
Good luck!
I think that we will have to agree to disagree on the toe out thing.

Having done thousands of take offs and landings in full scale taildraggers both single and twin engine plus thousands more with models, I will state that no one in the full scale world would knowingly put toe out in the main landing gear.

In the model world most of the runway surfaces are much rougher in proportion to the wheel diameter than in full scale. As such, the tire is in contact with the surface in a much less uniform condition and has less ability to counter the propeller and cross wind forces acting on the airframe.

Straight or toe in is the best bet and a plane does behave like a car in that it needs to track straight unless a control input tells it otherwise.
Old 09-04-2007, 04:53 PM
  #17  
Gremlin Castle
My Feedback: (14)
 
Join Date: Feb 2004
Location: Arlington, TX
Posts: 1,467
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs


ORIGINAL: gyrocptr

I've been flying tail-draggers for over 30 years; here are few things that may help your take-offs.
Locate the main wheel axles between 0-1.5 inches ahead of the leading edge of the wing. The more the main wheels are moved toward the front of the plane, the less the tendency to nose-over, but the greater the tendency to ground loop.
Toe-out the wheels 2-3 degrees. Yes, toe-out. A plane behaves differently than a car. When the plane starts to ground loop, the trailing-wheel lifts away from the ground while the leading-wheel "digs" into the ground. If the leading-wheel is toed-in, it "steers" in the direction of the ground loop and makes it worse. Toe-out in the leading-wheel will "steer" opposite the direction of the ground loop and have a counteracting effect.
Lengthen the tail wheel until the plane sits on level-ground, with about 10 degrees nose-up attitude. The more-level the plane sits, the lower the tendency to ground loop, but you want to have 5-10 degrees of nose-up angle available to generate lift for take-off.
Use little or no caster in the tail wheel. Extend the tail wheel strut straight down from the pivot-bearing or rudder hinge-line. Use a tiny bit of caster in the aft-direction, just to make sure the tail strut doesn't slant forward. The straight-strut will reduce the sensitivity of tail-wheel steering.
Start your take-off run with full up-elevator control to keep the tail wheel pressed against the ground for steering. As the plane accelerates, gradually reduce the amount of up-elevator. With the plane moving, aero-steering with the rudder will become effective.
As much as possible, take-off directly into the wind. This is especially helpful with high-wing planes that have dihedral. A tail-dragger will try to weather-vane into the wind. Cross-wind take-offs are a bear!
Practice, practice, practice to develop the appropriate, control-reflexes.
Good luck!
I think that we will have to agree to disagree on the toe out thing.

Having done thousands of take offs and landings in full scale taildraggers both single and twin engine plus thousands more with models, I will state that no one in the full scale world would knowingly put toe out in the main landing gear.

In the model world most of the runway surfaces are much rougher in proportion to the wheel diameter than in full scale. As such, the tire is in contact with the surface in a much less uniform condition and has less ability to counter the propeller and cross wind forces acting on the airframe.

Straight or toe in is the best bet and a plane does behave like a car in that it needs to track straight unless a control input tells it otherwise.
Old 09-09-2007, 09:00 PM
  #18  
thepope
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2001
Location: nestor falls, ON, CANADA
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Thanks to all who responded to my question. I moved the gear back and gave it some toe-in and it tracks great. Now that I have the take-off problem solved I am enjoying flying it alot more and it flies GREAT.
Bill
Old 05-21-2009, 05:48 AM
  #19  
rauljidy
Junior Member
 
Join Date: Dec 2005
Location: Miami Beach, FL
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

I just bought me a King on RCU....I'll be picking it up next week........I appreciate the insight in this forum as mine is set up as a Tail Dragger.....I was very happy to read there was a Happy ending to the Story

thepope, I'm thinking to eventually put this King on Floats.....I would very much like to hear your experiance with the King on Floats.....What Floats did you use
? Is your King setup with flaps?

ThankX for your insight.....

Old 05-30-2009, 01:26 PM
  #20  
JimCasey
Senior Member
My Feedback: (1)
 
JimCasey's Avatar
 
Join Date: Mar 2002
Location: Lutz, FL
Posts: 1,957
Likes: 0
Received 1 Like on 1 Post
Default RE: Flyin King Takeoffs

I have been flying an FK for 2 1/2 years now. Taildragger.
I never have a ground stability problem. I usually take off with a little backpressure on the stick. That keeps the tailwheel involved until the air rudder has enough flow to be effective. Seldom use the flaps for takeoff. I need to lead with a little right rudder and it definitely needs some right rudder on climbout. It's a completely stock FK, with an OS.91FS.


Attached Thumbnails Click image for larger version

Name:	Ig12348.jpg
Views:	52
Size:	72.4 KB
ID:	1208889  
Old 05-31-2009, 05:08 PM
  #21  
thepope
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2001
Location: nestor falls, ON, CANADA
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Yes it has flaps and the floats were Great Plains 60 size that I built. It really was difficult to control during takeoff. It was almost like there wasn't enough rudder to keep it straight. Now that I am more comfortable flying it I might put the floats back on.

ORIGINAL: rauljidy

I just bought me a King on RCU....I'll be picking it up next week........I appreciate the insight in this forum as mine is set up as a Tail Dragger.....I was very happy to read there was a Happy ending to the Story

thepope, I'm thinking to eventually put this King on Floats.....I would very much like to hear your experiance with the King on Floats.....What Floats did you use
? Is your King setup with flaps?

ThankX for your insight.....

Old 06-19-2009, 09:19 AM
  #22  
phildo
 
Join Date: Jan 2005
Location: Brisbane, AUSTRALIA
Posts: 50
Received 0 Likes on 0 Posts
Default RE: Flyin King Takeoffs

Gremlin Castle

"I think that we will have to agree to disagree on the toe out thing. "


Towin deffinately ..... and cambered inwards too helps I find.

It's funny how you think you KNOW something ... until proven different.



See photo of crop duster .... I know it flying but I'll bet there is camber and slight toe in also...


Sorry ... off subject ... a little.

Phil.
Attached Thumbnails Click image for larger version

Name:	Zx72127.jpg
Views:	35
Size:	54.0 KB
ID:	1220957  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.