What is the airspeed of F3a models??
10-18-2014, 02:08 AM
#26
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, discovered that the advance ratio is based on propeller diameter not the pitch. So my statement with respect to the advance ratio is not correct, sorry! However, that does impact the calculation. Your right there is a lot of assumptions, I have made even more that I have not stated.
You are right the best is to do a test, the only way to get a good value on the parameters we know have to guestimate. The speed you are measuring with a radar gun or GPS is the ground speed, so if you do the test on a windy day take the average of head- and tailwind flyby.
Gents, would be very interesting to hear your findings.
Regards,
Arnstein
10-20-2014, 11:38 PM
#27
Thread Starter
Hi
To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
Assumptions are that there are no friction and start speed is ZERO!
Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
Assumptions are that there are no friction and start speed is ZERO!
Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
10-21-2014, 08:35 AM
#29
I know you guys like to rely on your mathematical calculations however there is just so many unknowns that is going to throw it off. Dag, I think you box size is a bit large and that may be something that is throwing you off.From experience when flying pattern I try to fly as slowly as possible between maneuvers. I try to do this with IMAC as well. Rushing judges never results in optimal scores. That being said, for pattern I would have to put the ground speed at between 50 and 60 mph. Some good points have been made. For example if one wishes to fly slowly the airplane does have to be set up for it. As we all know, getting the perfect setup is like chasing the Holy Grail.
10-21-2014, 10:12 AM
#30
Thread Starter
I know you guys like to rely on your mathematical calculations however there is just so many unknowns that is going to throw it off. Dag, I think you box size is a bit large and that may be something that is throwing you off.From experience when flying pattern I try to fly as slowly as possible between maneuvers. I try to do this with IMAC as well. Rushing judges never results in optimal scores. That being said, for pattern I would have to put the ground speed at between 50 and 60 mph. Some good points have been made. For example if one wishes to fly slowly the airplane does have to be set up for it. As we all know, getting the perfect setup is like chasing the Holy Grail.
Well, the only thing I can rely on is the Mathematical fact as this is the input into calculations for attitude of slow moving airplane. I donot think I am throwing off. In my calculations I have used Box at 500m which is a little less than the measured 519 meters.
You agreed to the airplane does have to be set up to fly slow, however, how do you set up wing incidence, horizonta stab incidence when Your fuselage deck angle tells you you are 1-2 deg or more nose up. Maybe this is serching for holy grail, but still it can be calculated and shown mathematically.
Best regards
10-21-2014, 10:43 AM
#31
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A couple of years ago I tested the max speed with the GPS telemetry module. The plane was not one of the most modern and slow one, and it was powered by a Hacker C50-14XL with a APC 21*14. The average speed between up- and downwind level flight at full power was 150 km/h.
10-21-2014, 10:55 AM
#32
Thread Starter
A couple of years ago I tested the max speed with the GPS telemetry module. The plane was not one of the most modern and slow one, and it was powered by a Hacker C50-14XL with a APC 21*14. The average speed between up- and downwind level flight at full power was 150 km/h.
Thanks for info, 150km/h 0 93mi/h. Not very far off my envelope calculations. 150000m/ 3600s=41,66m/s.
Distance of 500 m is now 12 sec.
My max speed in calculation is 132km/h = 120 ft/sec which I will use in preliminary calculations.
Best Regards
10-21-2014, 11:08 AM
#33
Dag, your box dimensions are based on flying consistently 150 meters out? Yes that would be a box of that size however I don't think most guys fly that far out especially the lower classes. I may fly that far out with my 40% Extra but my pattern airplanes maybe 80 meters. Obviously this is going to make the box smaller. Now to get the airplane to fly slowly? I simply set it up with a little more positive wing incidence, 1 or 2 degree of down thrust and a slightly forward CG. This helped slow down the airplane but kept it on a straight line at different power settings. Obviously while inverted it has the opposite effect. That's the Holy Grail part of all of this. What you gain one place you are sure to loose someplace else. If I were to design yet another pattern airplane it would be one with slow draggy airfoils, thick trailing edges on the tail, retracts and be very symmetrical. Oh and the most important part, YS powered to be able to overcome all that drag when needed. Now how much will this actually improve scores? that will vary from region to region. Last pattern contest I flew I was down graded for snaps being " too slow ". Now if I was a familiar face in the pattern scene would that have happened? Maybe different where you are but for both pattern and IMAC over here you have to pay your dues for a couple years before you get the good scores.
10-21-2014, 11:26 AM
#34
Thread Starter
Dag, your box dimensions are based on flying consistently 150 meters out? Yes that would be a box of that size however I don't think most guys fly that far out especially the lower classes. I may fly that far out with my 40% Extra but my pattern airplanes maybe 80 meters. Obviously this is going to make the box smaller. Now to get the airplane to fly slowly? I simply set it up with a little more positive wing incidence, 1 or 2 degree of down thrust and a slightly forward CG. This helped slow down the airplane but kept it on a straight line at different power settings. Obviously while inverted it has the opposite effect. That's the Holy Grail part of all of this. What you gain one place you are sure to loose someplace else. If I were to design yet another pattern airplane it would be one with slow draggy airfoils, thick trailing edges on the tail, retracts and be very symmetrical. Oh and the most important part, YS powered to be able to overcome all that drag when needed. Now how much will this actually improve scores? that will vary from region to region. Last pattern contest I flew I was down graded for snaps being " too slow ". Now if I was a familiar face in the pattern scene would that have happened? Maybe different where you are but for both pattern and IMAC over here you have to pay your dues for a couple years before you get the good scores.
Thanks for Your interest!
Best regards
10-21-2014, 11:31 AM
#35
May be it is even too complicated for myself , discovered that the advance ratio is based on propeller diameter not the pitch. So my statement with respect to the advance ratio is not correct, sorry! However, that does impact the calculation. Your right there is a lot of assumptions, I have made even more that I have not stated.You are right the best is to do a test, the only way to get a good value on the parameters we know have to guestimate. The speed you are measuring with a radar gun or GPS is the ground speed, so if you do the test on a windy day take the average of head- and tailwind flyby.Gents, would be very interesting to hear your findings.Regards,Arnstein
, discovered that the advance ratio is based on propeller diameter not the pitch. So my statement with respect to the advance ratio is not correct, sorry! However, that does impact the calculation. Your right there is a lot of assumptions, I have made even more that I have not stated.You are right the best is to do a test, the only way to get a good value on the parameters we know have to guestimate. The speed you are measuring with a radar gun or GPS is the ground speed, so if you do the test on a windy day take the average of head- and tailwind flyby.Gents, would be very interesting to hear your findings.Regards,Arnstein
10-21-2014, 02:32 PM
#36
Hi
To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
Assumptions are that there are no friction and start speed is ZERO!
Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
Assumptions are that there are no friction and start speed is ZERO!
Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
10-21-2014, 10:04 PM
#37
Thread Starter
10-22-2014, 12:27 AM
#38
Hi Dag,
I think it is fair to say we are all making assumptions and a fair bit of guess work is involved. Most of those who have posted here, are saying their top speed is less than 100 mph/160 kph. This would be equivalent to full throttle at the bottom.
I just got back from flying and took notice of the speeds in down lines. Performing the 1/2 square loop with 1/2 roll down (in P15), I'm pushing over from level flight slightly slower than my normal level flight speed. Even from that speed and from the top line which is more distance than 100 m to the base line, my plane is not travelling any where near full throttle speed at the bottom. That's why I doubt the 160 kph speed from free fall at zero speed at the beginning.
The planes today are designed to be draggy and to fly slow to achieve that constant speed every one is looking for.
Just my observations of course.
I think it is fair to say we are all making assumptions and a fair bit of guess work is involved. Most of those who have posted here, are saying their top speed is less than 100 mph/160 kph. This would be equivalent to full throttle at the bottom.
I just got back from flying and took notice of the speeds in down lines. Performing the 1/2 square loop with 1/2 roll down (in P15), I'm pushing over from level flight slightly slower than my normal level flight speed. Even from that speed and from the top line which is more distance than 100 m to the base line, my plane is not travelling any where near full throttle speed at the bottom. That's why I doubt the 160 kph speed from free fall at zero speed at the beginning.
The planes today are designed to be draggy and to fly slow to achieve that constant speed every one is looking for.
Just my observations of course.
10-22-2014, 01:00 AM
#39
Thread Starter
Hi Dag,
I think it is fair to say we are all making assumptions and a fair bit of guess work is involved. Most of those who have posted here, are saying their top speed is less than 100 mph/160 kph. This would be equivalent to full throttle at the bottom.
I just got back from flying and took notice of the speeds in down lines. Performing the 1/2 square loop with 1/2 roll down (in P15), I'm pushing over from level flight slightly slower than my normal level flight speed. Even from that speed and from the top line which is more distance than 100 m to the base line, my plane is not travelling any where near full throttle speed at the bottom. That's why I doubt the 160 kph speed from free fall at zero speed at the beginning.
The planes today are designed to be draggy and to fly slow to achieve that constant speed every one is looking for.
Just my observations of course.
I think it is fair to say we are all making assumptions and a fair bit of guess work is involved. Most of those who have posted here, are saying their top speed is less than 100 mph/160 kph. This would be equivalent to full throttle at the bottom.
I just got back from flying and took notice of the speeds in down lines. Performing the 1/2 square loop with 1/2 roll down (in P15), I'm pushing over from level flight slightly slower than my normal level flight speed. Even from that speed and from the top line which is more distance than 100 m to the base line, my plane is not travelling any where near full throttle speed at the bottom. That's why I doubt the 160 kph speed from free fall at zero speed at the beginning.
The planes today are designed to be draggy and to fly slow to achieve that constant speed every one is looking for.
Just my observations of course.
Iam sorry to say it is Your personal opinion you advocates here. I asked you to substanciate the speed of a free falling Object say distance a 100 m. All you come up With is Your opinion how fast thing are moving.
Iam sure you do not deniing the influence of gravity and how that accellerate any Object, however, drag of the Object will certainly be deducted. My motive was to show how fast an Object gain speed under influence of gravity.
So under any cicumstance, Your speed over the top must be added to gravity accalleration minus drag. Please also note I have used the term OBJECT and not airplane in any of my posts.
I am still looking for measured horizontal speed.
Best regards
10-22-2014, 01:51 AM
#40
Hi,
1. Iam sorry to say it is Your personal opinion you advocates here. 2. I asked you to substanciate the speed of a free falling Object say distance a 100 m. 3. All you come up With is Your opinion how fast thing are moving.
Iam sure you do not deniing the influence of gravity and how that accellerate any Object, however, drag of the Object will certainly be deducted. 4. My motive was to show how fast an Object gain speed under influence of gravity.
So under any cicumstance, Your speed over the top must be added to gravity accalleration minus drag. Please also note I have used the term OBJECT and not airplane in any of my posts.
I am still looking for measured horizontal speed.
Best regards
1. Iam sorry to say it is Your personal opinion you advocates here. 2. I asked you to substanciate the speed of a free falling Object say distance a 100 m. 3. All you come up With is Your opinion how fast thing are moving.
Iam sure you do not deniing the influence of gravity and how that accellerate any Object, however, drag of the Object will certainly be deducted. 4. My motive was to show how fast an Object gain speed under influence of gravity.
So under any cicumstance, Your speed over the top must be added to gravity accalleration minus drag. Please also note I have used the term OBJECT and not airplane in any of my posts.
I am still looking for measured horizontal speed.
Best regards
2. You did not specifically ask me to substantiate the speed of a free falling Object say distance a 100 m. Below is what you asked.
Post #37
Originally Posted by drac1
All this really means nothing as you are just making assumptions. 160kph from 100 metres is doubtful.Hi,
OK, but substanciate why its doubtful!!
As the topic of the thread is" What is the airspeed of F3A models?", why would I talk about the speed of a free falling object?
3. My opinion or not, I can tell that my plane is not travelling at full throttle speed in my down lines and as the thread is about the speed of F3A models, my reply was more than relevant.
4.The topic of your thread says " What is the airspeed of F3A models?", so what has the falling speed of an OBJECT got to do with that? If that is what you want to know, then you are in the wrong place and the topic of your thread is misleading.
Last edited by drac1; 10-22-2014 at 02:01 AM.
10-22-2014, 02:00 AM
#41
Hi
1. To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
2. Assumptions are that there are no friction and start speed is ZERO!
3. Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
4. Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
1. To obtain the horizontal speed of a F3a airplane I have compard it With a free falling Object at 5kg.
2. Assumptions are that there are no friction and start speed is ZERO!
3. Vertical speed (free fall) sgrt(2*g*h) Input = 100meters, g= 9,8.
This Equals to 159,38 km/h = 44,27 m/s = ~145ft/s
If you increase the height to 200meters you get 62,61m/s which is 225 km/h .
4. Now, deduct for any breaking etc and the speed assumption will be more than a free fall from 100m ie 160km/h.
So, horizontal speed still remain open to asess!
Best regards
2. Everything has friction.
3. Talking about the speed of a free falling object.
4. Now you are talking about a F3A plane.
The comparisons you are making, are like comparing apples to oranges. It can not be done.
10-22-2014, 02:50 AM
#42
1. How can you compare the horizontal speed of an F3A plane to the speed of a free falling object?
2. Everything has friction.
3. Talking about the speed of a free falling object.
4. Now you are talking about a F3A plane.
The comparisons you are making, are like comparing apples to oranges. It can not be done.
2. Everything has friction.
3. Talking about the speed of a free falling object.
4. Now you are talking about a F3A plane.
The comparisons you are making, are like comparing apples to oranges. It can not be done.
Dag has repeatedly asked for 'measured' data.
It would just be interesting, if nothing else, to get some.
Derived data is but a poor substitute - I'm sure ,from what he has said, that he realises that.
'2. Everything has friction.' - An object at rest (velocity = 0) has no friction (drag).
Perspective affects opinion, so derived data is a little better than opinion.
eg ; compare your view of how 'slow' your model is at the bottom of a dive with how 'fast' a indoor model (the 'old' 125g + types) is at the bottom of a vertical dive relative to it's horizontal flying speed.
Brian
10-22-2014, 03:23 AM
#43
Hi drac,
Dag has repeatedly asked for 'measured' data.
It would just be interesting, if nothing else, to get some.
Derived data is but a poor substitute - I'm sure ,from what he has said, that he realises that.
'2. Everything has friction.' - An object at rest (velocity = 0) has no friction (drag).
Perspective affects opinion, so derived data is a little better than opinion.
1. eg ; compare your view of how 'slow' your model is at the bottom of a dive with how 'fast' a indoor model (the 'old' 125g + types) is at the bottom of a vertical dive relative to it's horizontal flying speed.
Brian
Dag has repeatedly asked for 'measured' data.
It would just be interesting, if nothing else, to get some.
Derived data is but a poor substitute - I'm sure ,from what he has said, that he realises that.
'2. Everything has friction.' - An object at rest (velocity = 0) has no friction (drag).
Perspective affects opinion, so derived data is a little better than opinion.
1. eg ; compare your view of how 'slow' your model is at the bottom of a dive with how 'fast' a indoor model (the 'old' 125g + types) is at the bottom of a vertical dive relative to it's horizontal flying speed.
Brian
I know dag is after measured level flight speed, but nothing in this thread so far is measured. It's either opinions or calculated data using many assumptions. Things such as the falling speed of an object can not be compared to the level flight of a F3A plane.
I know when something is not moving it has no friction/drag, but as the comment was about falling speed, that's what I was referring to.
1. Not really sure about the comparison?
It is possible to notice the difference of the entry speed to the down line speed. If the plane gets faster you can tell.
In the past I have wondered about the speed of pattern planes, but now I am also very interested to know for sure. I missed the perfect opportunity 2 weekends ago to find out and I'm not sure if I can arrange it again, but i'll try.
Scott
10-22-2014, 03:45 AM
#45
Scott,
Re the comparison ; Just trying to tweak the perspective a little.
An indoor model, again not the new sub 50g types, is very low on 'wing' loading etc.
It is more akin to a feather than a stone yet they appear to dive (straight down dive) more like a stone.
That appearance (perspective) is more to do with the space/height available than anything else - they are 'accelerating' hard all the way in that confined space and never get close to terminal velocity.
Our models do or get close in the dive heights involved - however I suspect we would be surprised at how fast the dives actually get.
I think this is what Dag is getting at.
we might be confusing reaching or approaching terminal velocity with 'slowing down' . (Not considering E braking)
Brian
Re the comparison ; Just trying to tweak the perspective a little.
An indoor model, again not the new sub 50g types, is very low on 'wing' loading etc.
It is more akin to a feather than a stone yet they appear to dive (straight down dive) more like a stone.
That appearance (perspective) is more to do with the space/height available than anything else - they are 'accelerating' hard all the way in that confined space and never get close to terminal velocity.
Our models do or get close in the dive heights involved - however I suspect we would be surprised at how fast the dives actually get.
I think this is what Dag is getting at.
we might be confusing reaching or approaching terminal velocity with 'slowing down' . (Not considering E braking)
Brian
Last edited by serious power; 10-22-2014 at 03:50 AM. Reason: Addition
10-22-2014, 05:11 AM
#46
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Dag, It's not the first time this issue comes out.
In another forum, the answer was given by a Herr in Germany who took the speed meter pistol and measured his plane in horizonal pass on the runway.
Measured 112 Km/h.
Don't know the wind speed, but you have to assume that the real speed of the plane was "something +/- wind speed = 112Km/h"
Only if wind was calm, plane was flying 112 Km/h
Cheers
G.
In another forum, the answer was given by a Herr in Germany who took the speed meter pistol and measured his plane in horizonal pass on the runway.
Measured 112 Km/h.
Don't know the wind speed, but you have to assume that the real speed of the plane was "something +/- wind speed = 112Km/h"
Only if wind was calm, plane was flying 112 Km/h
Cheers
G.
10-22-2014, 06:21 AM
#47
Thread Starter
Dag, It's not the first time this issue comes out.
In another forum, the answer was given by a Herr in Germany who took the speed meter pistol and measured his plane in horizonal pass on the runway.
Measured 112 Km/h.
Don't know the wind speed, but you have to assume that the real speed of the plane was "something +/- wind speed = 112Km/h"
Only if wind was calm, plane was flying 112 Km/h
Cheers
G.
In another forum, the answer was given by a Herr in Germany who took the speed meter pistol and measured his plane in horizonal pass on the runway.
Measured 112 Km/h.
Don't know the wind speed, but you have to assume that the real speed of the plane was "something +/- wind speed = 112Km/h"
Only if wind was calm, plane was flying 112 Km/h
Cheers
G.
That was wonderful News. Excatly what I was looking for.
Thank you
Best regards
10-22-2014, 07:03 AM
#48
Good luck hope this helps and if U get an answer post it please.
10-23-2014, 12:59 AM
#50
Thread Starter
Hi,
I have made some calculations based on input from this thread. Some adjustments has been done to the top speed.
The tabl[TABLE="width: 383"]
[TR]
[TD="width: 510, bgcolor: transparent, colspan: 4"]Speed envelope for a F3a airplane, according to input provided in RCU thread.
[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"]Speed @
[/TD]
[TD="class: xl74, bgcolor: transparent"]120 ft/sec
[/TD]
[TD="class: xl74, bgcolor: transparent"]100 ft/sec
[/TD]
[TD="class: xl76, bgcolor: transparent"]90 ft/sec
[/TD]
[/TR]
[TR]
[TD="class: xl72, bgcolor: transparent"][/TD]
[TD="class: xl75, bgcolor: transparent"]132 km/h
[/TD]
[TD="class: xl75, bgcolor: transparent"]110 km/h
[/TD]
[TD="class: xl77, bgcolor: transparent"]99 km/h
[/TD]
[/TR]
[TR]
[TD="class: xl71, bgcolor: transparent"]Parameters @
[/TD]
[TD="class: xl68, bgcolor: white"]Wing incidence
[/TD]
[TD="class: xl68, bgcolor: white"]Wing incidence
[/TD]
[TD="class: xl73, bgcolor: white"]Wing incidence
[/TD]
[/TR]
[TR]
[TD="class: xl63, bgcolor: transparent"][/TD]
[TD="class: xl69, bgcolor: white"]in 0,65°Condition
[/TD]
[TD="class: xl69, bgcolor: white"]in 0,87° Condition
[/TD]
[TD="class: xl69, bgcolor: white"]in 1,1 °Condition
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Wing Area in (sq in)
[/TD]
[TD="class: xl67, bgcolor: white"]984
[/TD]
[TD="class: xl65, bgcolor: transparent"]984
[/TD]
[TD="class: xl65, bgcolor: transparent"]984
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Horizontal Stab Area (sq in)
[/TD]
[TD="class: xl67, bgcolor: white"]244
[/TD]
[TD="class: xl65, bgcolor: transparent"]244
[/TD]
[TD="class: xl65, bgcolor: transparent"]244
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Moment arm Wcmac-Tcmac(in)
[/TD]
[TD="class: xl67, bgcolor: white"]41,5
[/TD]
[TD="class: xl65, bgcolor: transparent"]41,5
[/TD]
[TD="class: xl65, bgcolor: transparent"]41,5
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Horizontal Tail Volume
[/TD]
[TD="class: xl67, bgcolor: white"]0,74
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,74
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,74
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Fuelage Deck Angle (°)
[/TD]
[TD="class: xl67, bgcolor: white"]0,4
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,69
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,91
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Short Period Pitch Damping Ratio
[/TD]
[TD="class: xl67, bgcolor: white"]0,85
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,85
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,85
[/TD]
[/TR]
[TR]
[TD="class: xl63, bgcolor: transparent"]Horizontal Stab Incidence (°)
[/TD]
[TD="class: xl70, bgcolor: white"]0
[/TD]
[TD="class: xl66, bgcolor: transparent"]0
[/TD]
[TD="class: xl66, bgcolor: transparent"]0
[/TD]
[/TR]
[/TABLE]
e show how Incidence is influenced by speed at a constand wing and stab area.
Best regards
I forgot to mention that the Wing aero Angle of Attac= Fuselage Deck Angle + Wing incidence
Another thing is that Wing incidence has been adjusted to meet horizontal stab zero (°) incidence. The stab will get some negative incidence if one reduces the Wing incidence in all speed conditions.
I have made some calculations based on input from this thread. Some adjustments has been done to the top speed.
The tabl[TABLE="width: 383"]
[TR]
[TD="width: 510, bgcolor: transparent, colspan: 4"]Speed envelope for a F3a airplane, according to input provided in RCU thread.
[/TD]
[/TR]
[TR]
[TD="class: xl65, bgcolor: transparent"]Speed @
[/TD]
[TD="class: xl74, bgcolor: transparent"]120 ft/sec
[/TD]
[TD="class: xl74, bgcolor: transparent"]100 ft/sec
[/TD]
[TD="class: xl76, bgcolor: transparent"]90 ft/sec
[/TD]
[/TR]
[TR]
[TD="class: xl72, bgcolor: transparent"][/TD]
[TD="class: xl75, bgcolor: transparent"]132 km/h
[/TD]
[TD="class: xl75, bgcolor: transparent"]110 km/h
[/TD]
[TD="class: xl77, bgcolor: transparent"]99 km/h
[/TD]
[/TR]
[TR]
[TD="class: xl71, bgcolor: transparent"]Parameters @
[/TD]
[TD="class: xl68, bgcolor: white"]Wing incidence
[/TD]
[TD="class: xl68, bgcolor: white"]Wing incidence
[/TD]
[TD="class: xl73, bgcolor: white"]Wing incidence
[/TD]
[/TR]
[TR]
[TD="class: xl63, bgcolor: transparent"][/TD]
[TD="class: xl69, bgcolor: white"]in 0,65°Condition
[/TD]
[TD="class: xl69, bgcolor: white"]in 0,87° Condition
[/TD]
[TD="class: xl69, bgcolor: white"]in 1,1 °Condition
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Wing Area in (sq in)
[/TD]
[TD="class: xl67, bgcolor: white"]984
[/TD]
[TD="class: xl65, bgcolor: transparent"]984
[/TD]
[TD="class: xl65, bgcolor: transparent"]984
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Horizontal Stab Area (sq in)
[/TD]
[TD="class: xl67, bgcolor: white"]244
[/TD]
[TD="class: xl65, bgcolor: transparent"]244
[/TD]
[TD="class: xl65, bgcolor: transparent"]244
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Moment arm Wcmac-Tcmac(in)
[/TD]
[TD="class: xl67, bgcolor: white"]41,5
[/TD]
[TD="class: xl65, bgcolor: transparent"]41,5
[/TD]
[TD="class: xl65, bgcolor: transparent"]41,5
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Horizontal Tail Volume
[/TD]
[TD="class: xl67, bgcolor: white"]0,74
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,74
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,74
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Fuelage Deck Angle (°)
[/TD]
[TD="class: xl67, bgcolor: white"]0,4
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,69
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,91
[/TD]
[/TR]
[TR]
[TD="class: xl64, bgcolor: transparent"]Short Period Pitch Damping Ratio
[/TD]
[TD="class: xl67, bgcolor: white"]0,85
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,85
[/TD]
[TD="class: xl65, bgcolor: transparent"]0,85
[/TD]
[/TR]
[TR]
[TD="class: xl63, bgcolor: transparent"]Horizontal Stab Incidence (°)
[/TD]
[TD="class: xl70, bgcolor: white"]0
[/TD]
[TD="class: xl66, bgcolor: transparent"]0
[/TD]
[TD="class: xl66, bgcolor: transparent"]0
[/TD]
[/TR]
[/TABLE]
e show how Incidence is influenced by speed at a constand wing and stab area.
Best regards
I forgot to mention that the Wing aero Angle of Attac= Fuselage Deck Angle + Wing incidence
Another thing is that Wing incidence has been adjusted to meet horizontal stab zero (°) incidence. The stab will get some negative incidence if one reduces the Wing incidence in all speed conditions.
Last edited by DagTheElder; 10-23-2014 at 10:01 AM. Reason: Clarify.