Sort of aerodynamic question
#1
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I have 2 tail wheel kit and ready to change one big flat bottom trainer and the Avistar to a tail dragger.
Looking at the big wheel on the nose it seems to me that when making turns that nose wheel is a good 30-35* to the side and thats like pushing the wheel through the air sideways
Has anyone noticed a big difference with a change to a tail dragger/?
I'm also working with thin card board now but I do have a nice pattern made up to cover over most of the open gap under the nose.
With the front covered up close to 70% and the main wheels a full 1" smaller, and the nose wheel gone,how much faster do you think this plane will fly as far as straight and level flight goes from the stock configuration?
Looking at the big wheel on the nose it seems to me that when making turns that nose wheel is a good 30-35* to the side and thats like pushing the wheel through the air sideways
Has anyone noticed a big difference with a change to a tail dragger/?
I'm also working with thin card board now but I do have a nice pattern made up to cover over most of the open gap under the nose.
With the front covered up close to 70% and the main wheels a full 1" smaller, and the nose wheel gone,how much faster do you think this plane will fly as far as straight and level flight goes from the stock configuration?
#2
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From: Jewett, NY,
With the front covered up close to 70% and the main wheels a full 1" smaller, and the nose wheel gone,how much faster do you think this plane will fly as far as straight and level flight goes from the stock configuration?
#3

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From: Deland,
FL
Hmm, the absence of a nosewheel will decrease some drag and weight. Nose gears in the airstream are a significant cause of drag on FS planes. It makes more drag than the other 2 wheels put together because it is in the propwash.
That said, you are putting lipstick on a pig here. I'd say go ahead and do it, just for the experience with a taildragger. If speed is your objective, another plane is in order.
Make sure you rebalance the plane after removing the nose gear.
That said, you are putting lipstick on a pig here. I'd say go ahead and do it, just for the experience with a taildragger. If speed is your objective, another plane is in order.
Make sure you rebalance the plane after removing the nose gear.
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From: St Louis, MO
WhirleyBird, Don't be discouraged. Trying new things is part of the fun. Although you may not see a huge speed increase, your Avistar will look good as a tail dragger and you will have a chance to learn to fly that type of plane.
Using smaller wheels is fine if you fly on a paved runway. Bigger wheels are generally needed for grass strips.
Tom
Using smaller wheels is fine if you fly on a paved runway. Bigger wheels are generally needed for grass strips.
Tom
#5
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From: Bedford, UK
Whirley,
You won't see any improvement in top speed by changing to a taildragger. The nose wheel is drag but relatively insignificant compared to the wing. Would you believe that most of your drag is both flat plat and parasitic caused by the wing and stab? In addition, the intersection of the wing and fuselage (and stab and fuselage) creates almost as much drag as the whole wing! Check out the pylon forums for in depth explaination.
Don't be discouraged though. Once you fly with a tailwhell you'll never go back. 3-point landings and ground-loops will make the training wheel gang nuts! Seriously, put the tail whell on and beat up on the other trainers at fun fly events with your new short turning radius.
When we were scrapping together a "trainer" for my brother all we had was an Avistar .40 fuse, Planet .40 (pattern type) wing, and the tail feathers off of an Extra. Man did that thing haul butt! It was a lot of fune but ceased to be a trainer.
Chris
You won't see any improvement in top speed by changing to a taildragger. The nose wheel is drag but relatively insignificant compared to the wing. Would you believe that most of your drag is both flat plat and parasitic caused by the wing and stab? In addition, the intersection of the wing and fuselage (and stab and fuselage) creates almost as much drag as the whole wing! Check out the pylon forums for in depth explaination.
Don't be discouraged though. Once you fly with a tailwhell you'll never go back. 3-point landings and ground-loops will make the training wheel gang nuts! Seriously, put the tail whell on and beat up on the other trainers at fun fly events with your new short turning radius.
When we were scrapping together a "trainer" for my brother all we had was an Avistar .40 fuse, Planet .40 (pattern type) wing, and the tail feathers off of an Extra. Man did that thing haul butt! It was a lot of fune but ceased to be a trainer.
Chris
#6
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Whirley, Forgive me if I'm stating the obvious here, but don't forget to re-balance the plane after you ditch the nose gear!
Good Luck
Good Luck
#7
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Originally posted by Johng
Make sure you rebalance the plane after removing the nose gear.
Make sure you rebalance the plane after removing the nose gear.
I'll rebalance it.
I have all the hardware and going to make the change this weekend.
The prop wash was my primary concern also.
Thanks for the post.
#8
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Originally posted by greenboot
Using smaller wheels is fine if you fly on a paved runway. Bigger wheels are generally needed for grass strips.
Tom
Using smaller wheels is fine if you fly on a paved runway. Bigger wheels are generally needed for grass strips.
Tom
I can always change back the wheels if needed.
That tail dragger design seems to add a bit of class to the Avistar.
I saw one and so i'm changing mine over.
Thanks for the post
#9
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Originally posted by Chris300s
Whirley,
Chris
Whirley,
Chris
From the feed back so far it looks like I won't gain in the speed department but when I add the tail wheel and build up the front coweling it should at least look a bit more classy.
After this change I do have the 46 LX and that should push it a bit faster.
I'll be loading some PICs on Monday.
Thanks for the post
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From: Jewett, NY,
quote:
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Originally posted by Crashem
Not much if at all.
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THERE IS NO SUCH THING AS *i can't
WB I guess my answer to your very specific questions was misunderstood.
Just to clarify I'll repost your original question then maybe my answer will be clearer to you
No where did you ask if it was feasible to make this modification, Nor did you ask if you should make the modification.
My answer while brief fully answered your question to the best of my abilities. In the future before responding try to take the time to fully comprehend that which you are responding to.
I never said don't do this.. or you can't do this. I stated simply that greater speed would be negligible.
--------------------------------------------------------------------------------
Originally posted by Crashem
Not much if at all.
--------------------------------------------------------------------------------
THERE IS NO SUCH THING AS *i can't
WB I guess my answer to your very specific questions was misunderstood.
Just to clarify I'll repost your original question then maybe my answer will be clearer to you
With the front covered up close to 70% and the main wheels a full 1" smaller, and the nose wheel gone,how much faster do you think this plane will fly as far as straight
and level flight goes from the stock configuration?
and level flight goes from the stock configuration?
My answer while brief fully answered your question to the best of my abilities. In the future before responding try to take the time to fully comprehend that which you are responding to.
I never said don't do this.. or you can't do this. I stated simply that greater speed would be negligible.
#12
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Originally posted by Crashem
quote:
--------------------------------------------------------------------------------
No where did you ask if it was feasible to make this modification, Nor did you ask if you should make the modification.<--Right/
In the future before responding try to take the time to fully comprehend that which you are responding to.
How can I comprehend 5 words?
I never said don't do this.. or you can't do this. I stated simply that greater speed would be negligible.
quote:
--------------------------------------------------------------------------------
No where did you ask if it was feasible to make this modification, Nor did you ask if you should make the modification.<--Right/
In the future before responding try to take the time to fully comprehend that which you are responding to.
How can I comprehend 5 words?
I never said don't do this.. or you can't do this. I stated simply that greater speed would be negligible.
Your exact words were *Not much if at all*
As for me saying there is no such thing as *I CANT*was not directed to you.
You see I teach Wilderness Survival Skill.
I always tell everyone there is no such thing as *I CAN'T
In this post I applied that to myself rather then just say well I didn't get much encouragement so the heck with the mods.
I think you seemed to think that I directed that to you but that was not the case.
Lets just scratch it off as a misunderstanding
#13
Don't forget with making it a taildragger you will need to move the mains towards the front of the plane, preferrably just ahead of the main wing or it won't track on the ground without nosediving.
IMHO
Tom
IMHO
Tom
#14
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Originally posted by iflircaircraft
[B
Tom [/B]
[B
Tom [/B]
I'm looking over the plane right now and it seems I may have a slight problem because where I have to mount the mains (the same way their mounted now) I have to cut out the notch.
Thats no problem there.
The problem is the fuel tank is mounted right above that area and I don't think the extra thickness is there to take the screws.
I think i'll make a post asking for the anyone who made the mod let me know if they had problems.
I'm trying to aavoud mounting aluminum struts to the side of the fuse.
Thanks for the post
#15
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Originally posted by iflircaircraft
Tom
Tom
Where do you get your fuel?
Theres a place in Allentown,PA about an 1 hour ride from your location.
Forgot the name but he has the best prices I ever saw.
Have any info on that?
#16
WhirleyBird:
My wife has the same plane (she's learning) and is still in it's original trike configuration.
I just went out to the garage and took a look at hers and it seems you could put a 1/2"x1" hardwood block across the insde of the fuse bottom (howerver long you need it to fit snuggly) just forward of the former behind the fuel tank and drill holes to accept the landing gear wire. Just make sure you off-set the holes so the wires can cross.
With the 1/2" block you will have plenty of wood to screw the gear retainers to the bottom and also alllow you to cut a notch to accept the wire in the existing fuse bottom.
HMMMMMM I have some aluminum landing gear from an old plane laying around somewhere. LOL
I buy my fuel from Tower by the case.
I'm only 40 mins from Allentown, 30 from my LHS where I'll buy fuel in a pinch.
Good Luck on your endeavor.
Please re-balance the plane before flying it.
Tom
My wife has the same plane (she's learning) and is still in it's original trike configuration.
I just went out to the garage and took a look at hers and it seems you could put a 1/2"x1" hardwood block across the insde of the fuse bottom (howerver long you need it to fit snuggly) just forward of the former behind the fuel tank and drill holes to accept the landing gear wire. Just make sure you off-set the holes so the wires can cross.
With the 1/2" block you will have plenty of wood to screw the gear retainers to the bottom and also alllow you to cut a notch to accept the wire in the existing fuse bottom.
HMMMMMM I have some aluminum landing gear from an old plane laying around somewhere. LOL
I buy my fuel from Tower by the case.
I'm only 40 mins from Allentown, 30 from my LHS where I'll buy fuel in a pinch.
Good Luck on your endeavor.
Please re-balance the plane before flying it.
Tom
#17
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Originally posted by iflircaircraft
Tom
Tom
I cut the notch and then when I went inside the fuse that board where the battery and receiver sit are GLUED.
I put the mains back because I can't see tearing the balsa wood apart inside just to mount a block of wood.
Now I have to get filler and cover that up.
BTW.
Tower hobbies rip you on fuel.
If you buy 3 cases of the gallon jugs they charge you 1 shipping fee but 3 haz-mat fees.
About an hour ride from you is a place that sells nothing but RC fuel and you can get 5% Nitro for $8.95 a gallon.
Going skydiving.
See ya tonight (Mabye)
LOts of things cooking up on this end



