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Old Feb 11, 2011, 05:30 PM
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Hobby Zone Champ RTF

Per the manufacturer's site:

Teach yourself to fly RC airplanes in style with this exciting recreation of Aeronca’s beloved tail wheel airplane. Its small size and lightweight, durable construction let you fly with confidence in spaces as small as your own backyard without having to worry too much about crash damage. And it’s so easy to control you could be flying it like a pro in no time even if you’ve never flown an RC airplane before.

The HobbyZone® Champ is also equipped with the Spektrum 2.4GHz DSM2™ advantage: The Champ’s radio system uses the same Spektrum 2.4GHz DSM2 technology that is trusted by experienced RC pilots all around the world. With DSM2 technology you will enjoy complete freedom from signal interference whenever you fly. And after you teach yourself to fly, you can use the Champ’s transmitter to fly some of the Bind-N-Fly ultra micro aircraft from ParkZone and Blade. Visit bindnfly.com to see which ones.

Features
• Everything you need to Teach Yourself to Fly in one box- even the batteries
• Completely assembled and flight-ready
• 2.4GHz transmitter with Spektrum™ DSM® technology
• Scale wing rib detail and steerable tail wheel
• 1S 3.7V 150mAh Li-Po battery and DC Li-Po charger included
• Detailed instruction manual with flying tips included

Specifications
Type: Airplanes
Wingspan: 20.3 in (517mm)
Overall Length: 14.3 in (365mm)
Flying Weight: 1.3 oz (38g)
Radio: 4-channel 2.4GHz transmitter with Spektrum DSM 2; 3 channel receiver and aircraft
Prop Size: 130 x 70mm
Charger: DC 3.7V LiPo charger (included)
Recommended Battery: 3.7V 1S 150mAh LiPo (included)
Landing Gear: Fixed main with steerable tail wheel
Trim Scheme Colors: Yellow with orange trim
CG (center of gravity): Approximately 28mm from leading edge of the main wing

You Will Need...

Nothing! Everything is included in the box.




The instruction manual is taped under the foam packing. The english language portion is about +/- 20 pages. I removed and trashed the other 80-100 pages.


For comparison: Champ Tx top left, E-sky USB Tx top right, Xbox 360 controller bottom left, Syma s107g Tx bottom right.












Third party battery installed in this pic, glad I bought an extra at the same time I bought the Champ. One battery cycle at a time isn't enough...

This is my first RC plane. I lurked on these forums for a few weeks while playing with a Syma s107g and trying to decide how I wanted to begin. The overwhelming majority of posts recommended the Champ to novices, so I decided to go with that. Glad I did, I really like it and I was able to fly it right away.

About 2 weeks ago, I purchased an E-sky USB Tx and then bought Clearview Simulator. I started to try FMS, but there were an overabundance of threads with people asking for assistance in getting it to work on Win7. I would rather pay a few bucks for it to work right the first time than waste a ton of time getting a freeby to work right. And Clearview worked well, within a matter of minutes (if that) I was flying on the sim with the E-sky.

One note about Clearview Champ flying versus real Champ flying is the amount of throttle used. I started out by working the throttle almost all the way up like I do on the simulator and it was way too much for the real world application. I found my self only using about 25% when I was at the park. It's seems as though it would be hard to say whether or not the simulator helped. Because how would you know? You can't exactly compare before and after separately. I do feel that it helped me and was well worth the investment made for the E-sky and Clearview. I found myself doing turns and large figure 8's like I did on the simulator (and I was glad I practiced with the wind and weather options turned up too).

Here's my first and second landing...


1st Landing after about a 60 second flight.


2nd landing after about 90 seconds of flight. It got downwind of me and would not turn around. I was laughing the whole time, now knowing what those people on all those videos that showed their crashes felt like.

After these initial two landings, I did much better. The wind hampered me quite a bit though, as everyone else has stated, this light, little thing doesn't like the wind very much.

I looked for a Champ specific thread but couldn't find one. I'm not a total noob to forums, but I hope this isn't overkill. If anyone is on the fence about getting one of these and has a question, I was just standing in your shoes. Post your questions, I don't think I'm at any kind of experience level to give solid advice, but there are a ton of veterans posting on here that will gladly give you good advice.

Spleen out.
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Old Feb 11, 2011, 06:52 PM
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Keep your plane upwind of you... that was an important lesson I had to learn. Mine almost got a away from me downwind as it flew away from my little Champ transmitter and out of range.

The Champ is wonderful. Glad you are happy with your pick!
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Old Feb 12, 2011, 12:54 PM
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I love to fly my Champ, but only in calm or near calm winds.
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Old Feb 12, 2011, 01:56 PM
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It's nice to see a nice new Champ. The cowling on mine looks like the muzzle on a bulldog from repeated crashes. For a dedicated Champ thread, try this:

http://www.rcgroups.com/forums/showthread.php?t=1216910
or:

http://www.rcgroups.com/forums/showthread.php?t=1256836
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Old Feb 12, 2011, 04:46 PM
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When flying downwind when wind is present, you are going to want to apply MORE throttle. It sounds like a load of crap, but don't forget that when flying downwind, the ground speed may be higher, but the actual FLYING speed is a lot lower, so you will need to apply more throttle to keep the plane flying.
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Old Feb 12, 2011, 05:19 PM
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Quote:
Originally Posted by Scarface26 View Post
For a dedicated Champ thread, try this:
Yeah... Seems as though I have limited search skills. I definitely should have posted in one of those threads. Thanks for the links, I'll be checking those out. And I'll be adding the Micro RTF forum to my list of thread checks.
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Old Feb 13, 2011, 01:37 AM
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Originally Posted by Xpress.. View Post
When flying downwind when wind is present, you are going to want to apply MORE throttle. It sounds like a load of crap, but don't forget that when flying downwind, the ground speed may be higher, but the actual FLYING speed is a lot lower, so you will need to apply more throttle to keep the plane flying.
If you are flying DOWN WIND, Wind WILL be present. No?
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Old Feb 13, 2011, 02:06 AM
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Originally Posted by restlessswind View Post
If you are flying DOWN WIND, Wind WILL be present. No?
In fact groundspeed is a combination of flight speed by motor and that of wind. The aircraft doesn't care if the air is moving ... it sits in it and prop acts on it ... to the model the wind is apparent still air.

What other guy said is not strictly true as the airspeed of the model is same up or downwind.

ie : Airspeed 20mph, wind 10mph .......... downwind(going with wind) model will do 30mph groundspeed, upwind( flying against wind) 10mph groundspeed.

BUT to get back to you from downwind - you MUST increase throttle to exceed the wind speed so that nett result is fwd flight back to you. Models such as this champ like many foamies have a distinct problem of light weight and being blown around by wind adding to the problem to fly back. You see in many youtubes where the model tries to turn across the widn and FLIP BHAM CRASH she cartwheels in. What happens there is as the model banks and turns - the wing is slapped by the wind and down she goes. Keeping the turn powered and flat helps. But now we are onto more controls than you have on the champ ... so no wind when you fly is good idea !!
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Old Feb 13, 2011, 08:52 AM
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I think what XPRESS was expressing wasn't about flying at a constant airspeed/throttle setting, because in that case the plane does not really know there's any wind, but that,

If you are flying and adjusting the throttle and you are tempted to adjust the throttle on the downwind leg to keep the groundspeed the same as the upwind leg or the no-wind gndspd, DON'T, because that will make the airspeed too low.

Dave
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Old Feb 14, 2011, 11:55 AM
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Originally Posted by CNY_Dave View Post
I think what XPRESS was expressing wasn't about flying at a constant airspeed/throttle setting, because in that case the plane does not really know there's any wind, but that,

If you are flying and adjusting the throttle and you are tempted to adjust the throttle on the downwind leg to keep the groundspeed the same as the upwind leg or the no-wind gndspd, DON'T, because that will make the airspeed too low.

Dave
Yep, this is a common mistake that leads to a stall and, likely as not, a crash.
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Old Feb 15, 2011, 09:30 AM
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On the Champ and especially on the pkz Cub, if you are flying slow into a headwind and you want to turn down wind, you need to increase the throttle, then turn down wind, then you can decrease the throttle back to the same power setting.

If you try to turn with same power setting you were cruising at, the plane could fall out of the sky during the turn.

You don't need to do this as much in calm air, if at all, but a breeze can steal the lift off of the inside wing during a slow speed turn, made slower by the headwind.

The Champ doesn't tip stall like the Cub, so it doesn't need as much throttle to turn out of a headwind, but it still can use some.
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Old Feb 15, 2011, 11:06 AM
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[QUOTE=Scarface26;17388017]It's nice to see a nice new Champ. The cowling on mine looks like the muzzle on a bulldog from repeated crashes.QUOTE]

LOL! Mine too... I was just considering ordering a new fuse soon so I could fly it without embarassment!
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Old Feb 15, 2011, 11:20 AM
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Originally Posted by UNGN View Post
On the Champ and especially on the pkz Cub, if you are flying slow into a headwind and you want to turn down wind, you need to increase the throttle, then turn down wind, then you can decrease the throttle back to the same power setting.

If you try to turn with same power setting you were cruising at, the plane could fall out of the sky during the turn.

You don't need to do this as much in calm air, if at all, but a breeze can steal the lift off of the inside wing during a slow speed turn, made slower by the headwind.

The Champ doesn't tip stall like the Cub, so it doesn't need as much throttle to turn out of a headwind, but it still can use some.
Any plane will lose some energy when it enters a turn, so if near to stall speed an increase in power is needed to prevent a stall. However, the only thing affected by a tailwind is groundspeed. Airspeed is NOT affected by the direction an airmass is moving over the ground. Stall speed is the same no matter which way over the ground the airmass is moving.
Quote:
BRIEFING 3 - THE EFFECT OF WIND ON THE AIRCRAFT IN FLIGHT

There is probably more nonsense talked and written on this subject than any other connected with the practical side of flying! In reality, the matter is very simple - it is just that so many people find it hard to accept.

Provided that your flying area is clear of vertical obstructions (houses, trees, hedges, hangers etc.) the wind will blow fairly steadily from a constant direction once the aircraft is above about 50ft. Below this height, and depending on the surface of your flying site and the proximity of obstructions, there will be some turbulence both vertical and lateral.

Once you understand this principle you will see that a turn from an into wind heading to crosswind will appear to be a fairly sharp turn when seen from the ground and a turn from downwind to crosswind will appear to be slow and elongated. You must accept these visual effects for what they are and remember at all times that if you have not altered your throttle setting and the aircraft is at constant height then your airspeed is constant and the aircraft is in no danger of stalling.

Once the aircraft has climbed out of this turbulent level it is, in effect, flying in a steadily-moving block of air. Thus, with a windspeed of 10 mph the block of air in which your aircraft is flying is moving downwind at a speed of 10 mph. So, your aircraft which flies at a speed of, say 20 mph will appear to be doing only 10 mph when flying into the wind (flying speed less windspeed) and 30 mph when flying downwind (flying speed plus windspeed). In point of fact your aircraft knows nothing about the windspeed at all and is flying at a steady 20 mph all the time!

You will often hear people say that their aircraft tends to climb when turning into wind and dive when turning downwind. What is really happening, of course, is that they are subconsciously trying to compensate for the apparent variation in speed and themselves causing the aircraft to climb and dive.

One major point to remember - don’t try to keep your apparent speed constant or you will find that you will have your aircraft at full throttle when going into wind and stalling when it goes downwind.

If you find all this difficult to visualise, try to imagine yourself piloting a model boat from the bank of a fast-flowing river. In this situation you will find that you can understand the problems outlined above.

When flying in a wind of any strength you will find that your model can be carried away from you very quickly when it is travelling downwind. It is essential not to let it go too far. If you do, not only do you stand a good chance of losing control because you just can’t see the aircraft properly, but it is a long and slow slog back to your position against the full strength of the wind. There is another major factor - if your engine stops it will be difficult or impossible to glide the aircraft back to your position if it is too far downwind.
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Old Feb 15, 2011, 12:25 PM
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Originally Posted by Gerry__ View Post
Any plane will lose some energy when it enters a turn, so if near to stall speed an increase in power is needed to prevent a stall. However, the only thing affected by a tailwind is groundspeed. Airspeed is NOT affected by the direction an airmass is moving over the ground. Stall speed is the same no matter which way over the ground the airmass is moving.
The Champ loses much more energy in a turn out of a headwind than it does turning in calm air so things you do when its calm can result in a tip stalling crash when its windy.

If flying in wind, it's much more likely to drop the inside wing turning downwind than performing the same maneuver in calm air, even at a lower airspeed.
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Old Feb 15, 2011, 12:44 PM
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Originally Posted by UNGN View Post
The Champ loses much more energy in a turn out of a headwind than it does turning in calm air so things you do when its calm can result in a tip stalling crash when its windy.

If flying in wind, it's much more likely to drop the inside wing turning downwind than performing the same maneuver in calm air, even at a lower airspeed.
The Champ is light so more susceptible to gusts. BUT, with a steady, light breeze, the Champ will not be any more likely to stall turning from upwind to downwind than it would turning on a calm day.
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Old Feb 15, 2011, 12:58 PM
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Originally Posted by Gerry__ View Post
The Champ is light so more susceptible to gusts. BUT, with a steady, light breeze, the Champ will not be any more likely to stall turning from upwind to downwind than it would turning on a calm day.
Well, it is.

Go out at fly YOUR champ in a steady 7-10 mph wind and get back to us with your results.
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Old Feb 15, 2011, 01:16 PM
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Well, it is.

Go out at fly YOUR champ in a steady 7-10 mph wind and get back to us with your results.
Well read this: http://www.rcgroups.com/forums/showt...0#post17415872

Even if you encounter a gust from 7 to 10mph as you turn downwind, the low mass and inertia of the Champs will allow it to quickly regain airspeed. If you could view the Champs ASI (let's pretend it has a tiny, pixie sized one) all you would see is the needle fluctuate.

Maybe you are equating a turn downwind with an automatic reduction of airspeed over the wing with a resultant reduction in lift?
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Old Feb 15, 2011, 06:53 PM
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Originally Posted by Gerry__ View Post
Well read this: http://www.rcgroups.com/forums/showt...0#post17415872

Even if you encounter a gust from 7 to 10mph as you turn downwind, the low mass and inertia of the Champs will allow it to quickly regain airspeed. If you could view the Champs ASI (let's pretend it has a tiny, pixie sized one) all you would see is the needle fluctuate.

Maybe you are equating a turn downwind with an automatic reduction of airspeed over the wing with a resultant reduction in lift?
Please stop trying to equate real plane aerodynamics to a 1.5 OZ plane flying 8 mph in a 7mph wind, because that's apples and oranges.

When you turn downwind, the inside wing can drop and the plane can be pointed at the ground. Since this is the beginner area, beginners should be aware this can happen to them and increase the throttle before turning downwind.

The Parkzone J-3 can use this throttle increase even more than the Champ.

This isn't real aircraft theory, this is micro aircraft reality.
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Old Feb 16, 2011, 01:42 AM
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Please stop trying to equate real plane aerodynamics to a 1.5 OZ plane flying 8 mph in a 7mph wind, because that's apples and oranges.

When you turn downwind, the inside wing can drop and the plane can be pointed at the ground. Since this is the beginner area, beginners should be aware this can happen to them and increase the throttle before turning downwind.

The Parkzone J-3 can use this throttle increase even more than the Champ.

This isn't real aircraft theory, this is micro aircraft reality.
You don't know what you're talking about. Did you bother to read the link? You're a typical model flyer who thinks a tailwind reduces airspeed and lift.

During a turn, drag increases, and airspeed decreases, wind or not, that's why increasing power maintains the same airspeed.

Once the Champ is in a block of moving air that we call wind, its aerodynamics are the same as in zero wind. This rule applies to all objects supported by the air/flying. Boeings, balloons and butterflies all conform to this physical imperative.

Due to the low mass and low inertia of the Champ, it will only experience a momentary dip in airspeed if hit by a sudden tailwind gust, which it will quickly regain as the gust pushes against it.

Clearly you have been doing downwind turns in turbulence too near the ground and have rewritten the rules of physics to explain what you see, which is basically you mishandling the Champ.

This is the beginner area, so get your facts right.
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Old Feb 16, 2011, 06:37 AM
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Originally Posted by Gerry__ View Post
You don't know what you're talking about. Did you bother to read the link? You're a typical model flyer who thinks a tailwind reduces airspeed and lift.

During a turn, drag increases, and airspeed decreases, wind or not, that's why increasing power maintains the same airspeed.

Once the Champ is in a block of moving air that we call wind, its aerodynamics are the same as in zero wind. This rule applies to all objects supported by the air/flying. Boeings, balloons and butterflies all conform to this physical imperative.

Due to the low mass and low inertia of the Champ, it will only experience a momentary dip in airspeed if hit by a sudden tailwind gust, which it will quickly regain as the gust pushes against it.

Clearly you have been doing downwind turns in turbulence too near the ground and have rewritten the rules of physics to explain what you see, which is basically you mishandling the Champ.

This is the beginner area, so get your facts right.
The problem isn't during "headwind" or the "tailwind" but during the transition between the two. The Drag on an aerodynamic body in the plane/vector of the direction of travel IS HIGHER in a Crosswind than Flying straight in or out off the wind, so wind can cause much more drag on the plane in a turn than the same exact plane turning in still air.

Whatever. You are obviouly an expert on a plane you have never flown.

I repeat: Anything you posted about headwinds and tailwinds MAY NOT APPLY to a 8mph plane in a 7mph wind.

I'm not a cut and paste internet expert, like yourself, but do have an an Aeronautical Engineering degree from a major Aiviation University and have 21 years of working at major Aerospace companies and ACTUALLY OWN a Champ and ACTUALLY fly it in wind... so I Kinda know what I'm talking about.
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Old Feb 16, 2011, 07:02 AM
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Originally Posted by UNGN View Post
The problem isn't during "headwind" or the "tailwind" but during the transition between the two. The Drag on an aerodynamic body in the directrion of travel IS HIGHER in a Crosswind than Flying straight into the wind, so wind can cause much more drag on the plane in a turn than the same exact plane turning in still air.
Rubbish. And I'm going to make you eat those words. A turning plane has more drag than one flying straight and level. It matters not which way over the ground the air mass is moving, or whether it's moving at all, the amount of drag for any given turn is the same. Headwinds, tailwinds and crosswinds are issues for landing, taking off and navigation only. I suggest you go and do some research, the article I've posted is a good start.

Quote:
Whatever. You are obviouly an expert on a plane you have never flown.
Own one and have flown it in wind, so there is no mileage for you there.

Quote:
I repeat: Anything you posted about headwinds and tailwinds MAY NOT APPLY to a 8mph plane in a 7mph wind.
So now you hide behind 'MAY NOT APPLY'. Read the article and debate it with me in my blog, if you dare.

Quote:
I'm not a cut and paste internet expert, like yourself, but do have an an Aeronautical Engineering degree from a major Aiviation University and have 21 years of working at major Aerospace companies and ACTUALLY OWN a Champ and ACTUALLY fly it in wind... so I Kinda know what I'm talking about.
Yet you can't even spell 'aviation'. You have got yourself confused over the effects of turbulence and have put yourself in a deeply embarrassing position.
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Old Feb 16, 2011, 07:45 AM
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Well, I think yer both silly for thinking there's any smooth air within 100 feet of the ground!
None around here, anyway...

Thbthbtbt!


Dave
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Old Feb 16, 2011, 07:52 AM
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Rubbish. And I'm going to make you eat those words. A turning plan has more drag than one flying straight and level. It matters not which way over the ground the air mass is moving, or whether it's moving at all, the amount of drag for any given turn is the same. Headwinds, tailwinds and crosswinds are issues for landing, taking off and navigation only. I suggest you go and do some research, the article I've posted is a good start.
As the plane turns out of a headwind, its the equivalent of a sideslip in calm air and the increased drag on the plane in a sideslip applies.

This sideslip DOES NOT occur in calm air.

People don't fly full sized Champs in 70 mph winds, but if they did, I'm sure they find similar things happening when they turned downwind.

If you own a Champ go fly it in some wind. Fly it into the wind, throttle back to 1/3 throttle and then turn out of the wind.

Try it calm air and see how it behaves differently.
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Old Feb 16, 2011, 08:12 AM
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Originally Posted by UNGN View Post
As the plane turns out of a headwind, its the equivalent of a sideslip in calm air and the increased drag on the plane in a sideslip applies.

This sideslip DOES NOT occur in calm air.
Complete rubbish. The only things effected by the crosswind are the ground track and groundspeed. You really need to go and revisit the basics.

Quote:
People don't fly full sized Champs in 70 mph winds, but if they did, I'm sure they find similar things happening when they turned downwind.
Your problem is that you think a crosswind component has an effect on drag. This is very flawed thinking on your part. Drag increases due to the plane turning and said drag is not increased by the direction of travel over the ground of the air mass the plane is flying in. The increase in drug caused by a turn is the same in still air as it is if the air mass is moving.

Quote:
If you own a Champ go fly it in some wind. Fly it into the wind, throttle back to 1/3 throttle and then turn out of the wind.

Try it calm air and see how it behaves differently.
You need to read this:
Quote:
BRIEFING 3 - THE EFFECT OF WIND ON THE AIRCRAFT IN FLIGHT

There is probably more nonsense talked and written on this subject than any other connected with the practical side of flying! In reality, the matter is very simple - it is just that so many people find it hard to accept.

Provided that your flying area is clear of vertical obstructions (houses, trees, hedges, hangers etc.) the wind will blow fairly steadily from a constant direction once the aircraft is above about 50ft. Below this height, and depending on the surface of your flying site and the proximity of obstructions, there will be some turbulence both vertical and lateral.

Once you understand this principle you will see that a turn from an into wind heading to crosswind will appear to be a fairly sharp turn when seen from the ground and a turn from downwind to crosswind will appear to be slow and elongated. You must accept these visual effects for what they are and remember at all times that if you have not altered your throttle setting and the aircraft is at constant height then your airspeed is constant and the aircraft is in no danger of stalling.

Once the aircraft has climbed out of this turbulent level it is, in effect, flying in a steadily-moving block of air. Thus, with a windspeed of 10 mph the block of air in which your aircraft is flying is moving downwind at a speed of 10 mph. So, your aircraft which flies at a speed of, say 20 mph will appear to be doing only 10 mph when flying into the wind (flying speed less windspeed) and 30 mph when flying downwind (flying speed plus windspeed). In point of fact your aircraft knows nothing about the windspeed at all and is flying at a steady 20 mph all the time!

You will often hear people say that their aircraft tends to climb when turning into wind and dive when turning downwind. What is really happening, of course, is that they are subconsciously trying to compensate for the apparent variation in speed and themselves causing the aircraft to climb and dive.

One major point to remember - don’t try to keep your apparent speed constant or you will find that you will have your aircraft at full throttle when going into wind and stalling when it goes downwind.

If you find all this difficult to visualise, try to imagine yourself piloting a model boat from the bank of a fast-flowing river. In this situation you will find that you can understand the problems outlined above.

When flying in a wind of any strength you will find that your model can be carried away from you very quickly when it is travelling downwind. It is essential not to let it go too far. If you do, not only do you stand a good chance of losing control because you just can’t see the aircraft properly, but it is a long and slow slog back to your position against the full strength of the wind. There is another major factor - if your engine stops it will be difficult or impossible to glide the aircraft back to your position if it is too far downwind.

So always try to keep your aircraft upwind of your position as much as possible. By doing so you will save yourself from falling into some very difficult situations.
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Old Feb 16, 2011, 08:22 AM
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Originally Posted by CNY_Dave View Post
Well, I think yer both silly for thinking there's any smooth air within 100 feet of the ground!
I'm saying that he is observing the effects of turbulence and attributing these turbulence induced effects to some imagined effects of a crosswind component.

Amazing that someone so highly qualified can be so wrong.
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Old Feb 16, 2011, 08:53 AM
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Put a plane in a wind tunnel. Turn the plane 20 degrees to the direction of airflow and watch the drag in the direction of airflow double.

That's what's happening when you initially turn out of a headwind.

The Champ has mild tip stall characteristics and the wing may only dip, but the J-3 Cub will fall out of the sky, if you don't increase the power before turning.
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Old Feb 16, 2011, 09:18 AM
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Originally Posted by UNGN View Post
Put a plane in a wind tunnel. Turn the plane 20 degrees to the direction of airflow and watch the drag in the direction of airflow double.

That's what's happening when you initially turn out of a headwind.
Oh dear, oh dear! This plane, in this wind tunnel, it wouldn't be attached to the wind tunnel in any way, would it?

A turning plane has more drag than when it's flying straight. A crosswind does not create more drag for a plane as it turns.

You are wrong, horribly, horribly wrong. Run it by some of your colleagues at work, why don't you?

Headwinds and crosswinds are landing, take off and navigation consideration only and do not affect a plane's aerodynamic performance.

You still haven't bothered to read any of the stuff I have provided for you, have you?
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Old Feb 16, 2011, 12:02 PM
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Originally Posted by Gerry__ View Post
Oh dear, oh dear! This plane, in this wind tunnel, it wouldn't be attached to the wind tunnel in any way, would it?

A turning plane has more drag than when it's flying straight. A crosswind does not create more drag for a plane as it turns.

You are wrong, horribly, horribly wrong. Run it by some of your colleagues at work, why don't you?

Headwinds and crosswinds are landing, take off and navigation consideration only and do not affect a plane's aerodynamic performance.

You still haven't bothered to read any of the stuff I have provided for you, have you?
I used the wind tunnel example to explain the throry behind what I'm trying to explain to you, but it doesn't appear you are getting it.

A plane flying directly into a headwind has lower drag than a plane flying into the same headwind with a 5 degree sideslip, correct?

When you turn out of a headwind in a slab sided highwing drag goes up much more than if are making the same turn in calm air.

The reasons for this is the increase in the effective frontal area of the plane (Because the sides of the plane are now part of the frontal area) and the Increase in the drag coef of the plane angled to the airflow.

On a highwing, slab sided plane, this drag increase could be 2X the drag of a plane flying directly into a headwind at some point in the turn and in the direction of the travel of the plane it would be the Drag X COS of the angle to the airflow, which at 20 degrees of turn is still 90%.

On a real plane that isn't flying in winds that are 150% of stall speed, you may not see this as much... but if you did, you would.
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Old Feb 16, 2011, 12:32 PM
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Gentlemen,

A very interesting discussion; one that has been repeated numerous times on various threads and in various forums. While the laws of Newtonian Physics always apply (when we are not dealing with things on the microscopic level or nearing the speed of light) two things are important to remember. One is that objects with a very low mass, and consequently a low inertia, will react in an exagerated manner compared to their heavier, larger counterparts when an outside force is applied. The other is that our perception, while standing on the ground, is not that same as it would be if we were in the first person, sitting inside the plane.

As far as the discussion between Gerry and UNGN, Gerry has presented the far more accurate information. When you turn a plane, no matter what plane it is, it will loose lift. There are several ways to compansate for this loss, but if you took absolutely no action, you would find that the plane will be at a lower altitude when it exits the turn then when it entered. If you do this in calm conditions the loss of altitude occurs over a considerable amount of "land". However, if you do the same thing when you have a strong headwind, the loss will appear to be compressed over a short amount of land and will make the plane appear to be about to stall. When you compare flight in calm air to flight in STEADY wind, there is absolutely no difference as far as the plane is concerned until you are either taking off or landing. However, steady wind is very hard to find when you are flying parkflyers, particularly Micros. Once the wind starts to change in speed, direction or both, all kinds of strange forces start to act upon the plane and it can exhibit very strange and unnerving flight characteristics.

For example, take the PZ J3Cub or SuperDecathlon, neither of which is a Micro, but are on the small side of Parkflyers. They are both fairly notorious for being hard to fly in wind. Take them out on a windy day and try to fly them at 50 - 100 ft. They will be quite a handfull and will exhibit all sorts of strange behavior. Now take them up to 800 ft. (yes, they will appear as a tiny little spec) but they will exhibit completely normal flight characteristics within their moving air mass.
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Old Feb 16, 2011, 12:41 PM
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Originally Posted by UNGN View Post
I used the wind tunnel example to explain the throry behind what I'm trying to explain to you, but it doesn't appear you are getting it.

A plane flying directly into a headwind has lower drag than a plane flying into the same headwind with a 5 degree sideslip, correct?

When you turn out of a headwind in a slab sided highwing drag goes up much more than if are making the same turn in calm air.

The reasons for this is the increase in the effective frontal area of the plane (Because the sides of the plane are now part of the frontal area) and the Increase in the drag coef of the plane angled to the airflow.

On a highwing, slab sided plane, this drag increase could be 2X the drag of a plane flying directly into a headwind at some point in the turn and in the direction of the travel of the plane it would be the Drag X COS of the angle to the airflow, which at 20 degrees of turn is still 90%.

On a real plane that isn't flying in winds that are 150% of stall speed, you may not see this as much... but if you did, you would.
For a plane flying in a mass of air, there is no headwind, or crosswind or tailwind. These components only come into consideration for landing, take off and navigation.

As far as the plane is concerned, it only has airspeed, that is speed in relation to the air molecules it is flying through. That the mass of air that the plane is fly through is moving across the ground is of absolutely no aerodynamic importance.

For the plane, there is only airspeed. There is no increase in drag when turning in an air mass that is moving in relation to the ground. And you still haven't bothered to read the articles I posted.

Now let's deal with this bit in detail:

Quote:
A plane flying directly into a headwind has lower drag than a plane flying into the same headwind with a 5 degree sideslip, correct?
You are confusing headwind with airspeed. Read the article by Jim Davis. You are really embarrassing yourself.
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