Doc James Hammond
Very Strong User
All done with now. Its Miller time!
Doc.
Doc.
Aloft Forums
Welcome to Aloft Forums. Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!
Redshift emerges.
- Thread starter Doc James Hammond
- Start date
Konrad
Very Strong User
I'd like to see the post crash fuselage wing joiner box.
Also does Aeroic have a cut away drawing showing the structural make up of the wings? I find this information very helpful during both the purchase and repair phase of the model's life.
Vladimer Models has some very good drawings showing what one is getting with the various products.
Doc James Hammond
Very Strong User
Wow, the camo really works! That is why I don't like it, the camo that is.
Miller time! Now that an ad campaign I haven't heard since the 70's.
Hahaha...now I understand too Konrad.
That camo scheme makes the plane almost impossible to see against the sky!
I mean...is it a bird...? Is it a plane..?
Its so hard to see I can't tell!
By the way the only visible part of the wing in the "bush" picture was the part with NO camo (Centre, slightly left) - the underside of the wing.
As to the beer, actually, it was Arschbrenner Gefartenbrau they were drinking...I think, but
"Arschgebrenner Gefartenbrau time" is too hard for me to write.
Cheers,
Doc.
Last edited:
Doc James Hammond
Very Strong User
Quote:
the model was undamaged other than a slight crease to one tailplane half.
The fuselage does not have any wing Joiner box, pre, or post crash Konrad.
Cheers,
Doc J.
Konrad
Very Strong User
I hope the fuselage doesn't show damage. But often times damage is over looked or very difficult to see. (See my mid repair failure here).
https://forum.alofthobbies.com/inde...ls-60-glass-and-rohacell-racer.367/#post-4002
https://forum.alofthobbies.com/index.php?threads/manufacturing-design-flaws.365/
No wing joiner box? How are the wings attached to the fuselage? How does the wing joiner pass through the fuselage?
I'll take another look at the fuselage as I thought the wing were shoulder mounted, not top mounted like a single piece wing.
Edit to add links
Doc James Hammond
Very Strong User
Doc James Hammond
Very Strong User
Hi Konrad, nope no fuselage joiner box.
In fact I don't know if any F3f or f3b plane that has one.
Its detrimental as it will lead to cracking, and its not needed. The pins hold the wing in position and the joiner (massive in most of my models) fits loosely through the fuselage with the bridge formed between the wings making the line of stress.
The wing joiner passes through the fuselage by a sliding fit.
Have you had a good look at a current F3b or F3f? - I think you need to take a longer look at current construction and design methods.
Cheers,
Doc.
In fact I don't know if any F3f or f3b plane that has one.
Its detrimental as it will lead to cracking, and its not needed. The pins hold the wing in position and the joiner (massive in most of my models) fits loosely through the fuselage with the bridge formed between the wings making the line of stress.
The wing joiner passes through the fuselage by a sliding fit.
Have you had a good look at a current F3b or F3f? - I think you need to take a longer look at current construction and design methods.
Cheers,
Doc.
Konrad
Very Strong User
Ok Doc,
What do you call this? I've seen you models even the Red Shift and noticed that the massive joiner has a slip fit with little or no clearance through the fuselage ( joiner box?). I recall see you struggling to fit a joiner through a fuselage when I visited Aloft.
Are you saying that your fuselage and wing joint use a free floating spar configuration?
"I think you need to take a longer look at current construction and design methods." Without a doubt! That is why I'm asking the premier designer.
What do you call this? I've seen you models even the Red Shift and noticed that the massive joiner has a slip fit with little or no clearance through the fuselage ( joiner box?). I recall see you struggling to fit a joiner through a fuselage when I visited Aloft.
Are you saying that your fuselage and wing joint use a free floating spar configuration?
"I think you need to take a longer look at current construction and design methods." Without a doubt! That is why I'm asking the premier designer.
Doc James Hammond
Very Strong User
Its a rectangular hole only Konrad.
The same as every other F3f or F3b - or F3 anything as far as I know. There are no walls and no structure there other than the normal reinforcements. Think about it - why would there be?
I have no idea what a free floating spar might mean.
I'm frankly really quite shocked that you did not know this.
Doc.
The same as every other F3f or F3b - or F3 anything as far as I know. There are no walls and no structure there other than the normal reinforcements. Think about it - why would there be?
I have no idea what a free floating spar might mean.
I'm frankly really quite shocked that you did not know this.
Doc.
Konrad
Very Strong User
You might be surprised at what all I don't know?
Why any reinforcements if there are no walls or structure?
So the full weight and air loads from the fuselage are carried on what I think are alignment pins?
I also don't see how the pins would hold the fuselage in alignment along the longitudinal axis. Maybe there isn't too much force along this axis and that the length of the pins inside their receptacle is sufficient to resist this, keeping the tail in vertical alignment .
Is there a white paper detailing this type of wing to fuselage attachment?
I've come to the conclusion that there is a lot of load on this "rectangular hole" as every used fuselage I see presents stress cracks.
Doc James Hammond
Very Strong User
Konrad, like many mechanical structures that have been used for some time - this one works, and as far as I know is used universally.
With two 6mm pins each side to align the wings, and a huge wing joiner joining them, there is no need at all for any supporting structure within the fuselage joiner hole.
These parts should be floating along the X-Y axis to a limited extent, and though the joining areas of the fuselage should be adequately reinforced and designed for the job, it would actually be detrimental to have them too stiff.
Some parts of the models simply cannot be made completely crash proof and need a certain amount of "Give" or the ability to move a little during a crash or a hard landing. I have seen stress cracks and even failures in this area, and this is one reason why I'm working to make my wing joiners on the new designs with rounded corners and the receptacles with rounded edges too - including the fuselage and the wing joiner boxes.
Another reason for rounding is to lessen the possibility of the wing joiner being prevented from a smooth fit due to a sharp corner being obstructed somewhere - as you saw in Wayne's shop. I have had models from other manufacturers where the wing joiners have had to be hydraulically removed from the joiner boxes in the wings, and I have had others where you could probably toss it into the wing.
I'm well aware of what happens when we have an unplanned meeting with terra firma and I can tell you that there is only so far you can go, reasonably to prevent damage. Thats why I make my ballast boxes - a personal preference - with a stiff foam keeper instead of a mechanical screwed in contrivance.
Knowing the tolerances and fits needed to do a good job is really important in design, keeping them is also very important in manufacture.
I hope that helps.
Doc.
With two 6mm pins each side to align the wings, and a huge wing joiner joining them, there is no need at all for any supporting structure within the fuselage joiner hole.
These parts should be floating along the X-Y axis to a limited extent, and though the joining areas of the fuselage should be adequately reinforced and designed for the job, it would actually be detrimental to have them too stiff.
Some parts of the models simply cannot be made completely crash proof and need a certain amount of "Give" or the ability to move a little during a crash or a hard landing. I have seen stress cracks and even failures in this area, and this is one reason why I'm working to make my wing joiners on the new designs with rounded corners and the receptacles with rounded edges too - including the fuselage and the wing joiner boxes.
Another reason for rounding is to lessen the possibility of the wing joiner being prevented from a smooth fit due to a sharp corner being obstructed somewhere - as you saw in Wayne's shop. I have had models from other manufacturers where the wing joiners have had to be hydraulically removed from the joiner boxes in the wings, and I have had others where you could probably toss it into the wing.
I'm well aware of what happens when we have an unplanned meeting with terra firma and I can tell you that there is only so far you can go, reasonably to prevent damage. Thats why I make my ballast boxes - a personal preference - with a stiff foam keeper instead of a mechanical screwed in contrivance.
Knowing the tolerances and fits needed to do a good job is really important in design, keeping them is also very important in manufacture.
I hope that helps.
Doc.
Last edited:
Konrad
Very Strong User
Doc, Thanks for your input. I think the veils of ignorance are slowly lifting.
"like many mechanical structures that have been used for some time - this one works, and as far as I know is used universally."- Doc
In my field (commercial air transports) that is not a technical justification. I've been the impetus of 2 FAA ADs (Airworthy Directives) when I showed that well established "appliances" failed contrary to established engineering models (expectations).
"Knowing the tolerances and fits needed to do a good job is really important in design, keeping them is also very important in manufacture."-Doc
The understanding of Form, Fit and Function is critical in getting the most from any design. What I don't understand is how the pins are to work in transmitting air loads (control) and structural load (air and landing) between the fuselage and wings.
In my limited sample size of used gliders all , other than round joiners, had damage in and around this through hole. This leads me to think there is an short coming in the design. (Not yours per say but the design in general).
"With two 6mm pins each side to align the wings, and a huge wing joiner joining them, there is no need at all for any supporting structure within the fuselage joiner hole."-Doc
This I don't see or understand how these would actually work. Large pins 6mm (1/4") by 16mm (5/8") might actually offer adequate contact area in Feature "A" (see attached cartoon). This is why I asked for detailed photos of the "crashed" ship.
"These parts should be floating along the X-Y axis to a limited extent, and though the joining areas of the fuselage should be adequately reinforced and designed for the job, it would actually be detrimental to have them too stiff."-Doc
Not sure I understand what are the X and Y axis. Most floating joiners, that I've seen, allow the fuselage and wing to move in 3 axes. Not only move in these axes but also rotate in these axes.
This is key to my understanding, "These parts should be floating along the X-Y axis to a limited extent". What is the limited extent? The few used Aeroic designs I saw appeared to have a clearance between the wing joiner and the fuselage of 0.Xmm. This should allow the fuselage and wing to flex well within the elastic limits of the material of Feature "A" until the fuselage and joiner come into play to take up the extreme loads.
On the Sanda designs I see a huge (by an order of magnitude increase in this clearance [X.0mm]) clearance between the fuselage and the wing joiner. I can't see the joiner and fuselage having any interaction until the wings are jettisoned!
"Some parts of the models simply cannot be made completely crash proof and need a certain amount of "Give" or the ability to move a little during a crash or a hard landing."-Doc
Yes, flexible structures are often much more durable than stiff, rigid structures. Take for example your ballast mount. Nobody is expecting "Crash Proof". What we are looking for are structures that withstand the expected loads and demands of everyday use. For me that means a lot of torsional loads as the ship comes to a skidding, whipping (ground loop like), stop on landings.
Doc, As this is a design that is not unique to Aeroic models I'm going to start a separate thread on the limitations (constraints) of the through spar (joiner) system. I welcome your input in that thread.
https://forum.alofthobbies.com/inde...a-modern-rc-glider-how-do-these-function.577/
Disclaimer:
I want to make it clear that I know nothing about the dynamics of this system. I've seen similar designs (used/worn) with indications of pending failure and want to understand how they work. I'm in no way implying that any OEM has a design flaw in the design that uses these through joiners and pins. This is about me wanting to understand how they work.
All the best,
Konrad
Edit: to add link
"like many mechanical structures that have been used for some time - this one works, and as far as I know is used universally."- Doc
In my field (commercial air transports) that is not a technical justification. I've been the impetus of 2 FAA ADs (Airworthy Directives) when I showed that well established "appliances" failed contrary to established engineering models (expectations).
"Knowing the tolerances and fits needed to do a good job is really important in design, keeping them is also very important in manufacture."-Doc
The understanding of Form, Fit and Function is critical in getting the most from any design. What I don't understand is how the pins are to work in transmitting air loads (control) and structural load (air and landing) between the fuselage and wings.
In my limited sample size of used gliders all , other than round joiners, had damage in and around this through hole. This leads me to think there is an short coming in the design. (Not yours per say but the design in general).
"With two 6mm pins each side to align the wings, and a huge wing joiner joining them, there is no need at all for any supporting structure within the fuselage joiner hole."-Doc
This I don't see or understand how these would actually work. Large pins 6mm (1/4") by 16mm (5/8") might actually offer adequate contact area in Feature "A" (see attached cartoon). This is why I asked for detailed photos of the "crashed" ship.
"These parts should be floating along the X-Y axis to a limited extent, and though the joining areas of the fuselage should be adequately reinforced and designed for the job, it would actually be detrimental to have them too stiff."-Doc
Not sure I understand what are the X and Y axis. Most floating joiners, that I've seen, allow the fuselage and wing to move in 3 axes. Not only move in these axes but also rotate in these axes.
This is key to my understanding, "These parts should be floating along the X-Y axis to a limited extent". What is the limited extent? The few used Aeroic designs I saw appeared to have a clearance between the wing joiner and the fuselage of 0.Xmm. This should allow the fuselage and wing to flex well within the elastic limits of the material of Feature "A" until the fuselage and joiner come into play to take up the extreme loads.
On the Sanda designs I see a huge (by an order of magnitude increase in this clearance [X.0mm]) clearance between the fuselage and the wing joiner. I can't see the joiner and fuselage having any interaction until the wings are jettisoned!
"Some parts of the models simply cannot be made completely crash proof and need a certain amount of "Give" or the ability to move a little during a crash or a hard landing."-Doc
Yes, flexible structures are often much more durable than stiff, rigid structures. Take for example your ballast mount. Nobody is expecting "Crash Proof". What we are looking for are structures that withstand the expected loads and demands of everyday use. For me that means a lot of torsional loads as the ship comes to a skidding, whipping (ground loop like), stop on landings.
Doc, As this is a design that is not unique to Aeroic models I'm going to start a separate thread on the limitations (constraints) of the through spar (joiner) system. I welcome your input in that thread.
https://forum.alofthobbies.com/inde...a-modern-rc-glider-how-do-these-function.577/
Disclaimer:
I want to make it clear that I know nothing about the dynamics of this system. I've seen similar designs (used/worn) with indications of pending failure and want to understand how they work. I'm in no way implying that any OEM has a design flaw in the design that uses these through joiners and pins. This is about me wanting to understand how they work.
All the best,
Konrad
Edit: to add link
Last edited:
Doc James Hammond
Very Strong User
Look forward to the new thread Konrad.
Doc.
Doc.
jvaliensi
Active User
Hi,
I am wondering when the Redshift will hit these shores? Hyperflight UK has a couple in stock and I'm temped, but I prefer to support the USA dealer. Will the new stock have improvements over the 1st few production runs?
BTW - I need the white-black-green camo to match my lost Schwing Corsa.
Cheers!
BTW - With the typical pass-thru spar, which is floating in the wing, there is compressive loads passed on to the fuselage. This happens with increased G's as the wing tries to bend up wards. The top edge of the wings try to get closer together and the fuselage is squeezed. I'm guessing that so many sailplanes are built like this and there is no failure of the fuselage from the compression loading, that this means the compressive loads are less than the failure point of the fuselage.
Twisting load is another force transferred to the fuselage. The wing is made nice and stiff but if the spar and four pins can not resist the bending the stiff wing will move. A tight fitting spar in the wing box will help here. The pins are far enough from the twisting axis that they have an advantage of leverage to transfer the loads.
The DS sailplanes remove these loads from the fuselage by using a one piece wing. I don't think F3F or F3B speeds are high enough to require a one piece wing. 90mph vs 500+mph!
So - retangular spars are better than round ones. A designer could pass the forward and aft pins completely thru the fuselage to tie the wing halves together to help resist twisting and remove the load from the fuselage. A spar box thru the fuselage appears unnecessary based on the success of so many designs. (A spar box would make building the sailplane much harder, too.)
I am wondering when the Redshift will hit these shores? Hyperflight UK has a couple in stock and I'm temped, but I prefer to support the USA dealer. Will the new stock have improvements over the 1st few production runs?
BTW - I need the white-black-green camo to match my lost Schwing Corsa.
Cheers!
BTW - With the typical pass-thru spar, which is floating in the wing, there is compressive loads passed on to the fuselage. This happens with increased G's as the wing tries to bend up wards. The top edge of the wings try to get closer together and the fuselage is squeezed. I'm guessing that so many sailplanes are built like this and there is no failure of the fuselage from the compression loading, that this means the compressive loads are less than the failure point of the fuselage.
Twisting load is another force transferred to the fuselage. The wing is made nice and stiff but if the spar and four pins can not resist the bending the stiff wing will move. A tight fitting spar in the wing box will help here. The pins are far enough from the twisting axis that they have an advantage of leverage to transfer the loads.
The DS sailplanes remove these loads from the fuselage by using a one piece wing. I don't think F3F or F3B speeds are high enough to require a one piece wing. 90mph vs 500+mph!
So - retangular spars are better than round ones. A designer could pass the forward and aft pins completely thru the fuselage to tie the wing halves together to help resist twisting and remove the load from the fuselage. A spar box thru the fuselage appears unnecessary based on the success of so many designs. (A spar box would make building the sailplane much harder, too.)
Doc James Hammond
Very Strong User
Hi James, All my stuff is delayed for a short time because of a few things that I'm not in control of.
Highly frustrating but nothing I can do.
I have two Redshift here in stock but they are camo/red trim double carbon versions.
There is now a lightweight version which went quite well at the world championships recently when there was little of no wind. No other improvements.
The "standard" wing/fuselage joining system as its stands works well enough, and though there is inevitable too for improvements its not a show stopper. Generally if there are cracks, then these develop and are repaired over some time along with the rest of the bangs, dents and scuffs that the hard flown model inevitably suffers.
Like the old guys say - If a machine works, don't fix it.
But communication and lots of ideas are always good and so are new theories.
Cheers,
Doc J.
Highly frustrating but nothing I can do.
I have two Redshift here in stock but they are camo/red trim double carbon versions.
There is now a lightweight version which went quite well at the world championships recently when there was little of no wind. No other improvements.
The "standard" wing/fuselage joining system as its stands works well enough, and though there is inevitable too for improvements its not a show stopper. Generally if there are cracks, then these develop and are repaired over some time along with the rest of the bangs, dents and scuffs that the hard flown model inevitably suffers.
Like the old guys say - If a machine works, don't fix it.
But communication and lots of ideas are always good and so are new theories.
Cheers,
Doc J.
Doc James Hammond
Very Strong User
Hey Guys, here is a link to an ongoing Redshift Build thread in the UK. They seem to be getting along OK with it so far.
https://www.modelflying.co.uk/forum...W1vXt3N58dA2Rzw7RBavumkYqWgEwfVpIoNvIYUCXk3rM
Cheers,
Doc.
https://www.modelflying.co.uk/forum...W1vXt3N58dA2Rzw7RBavumkYqWgEwfVpIoNvIYUCXk3rM
Cheers,
Doc.
purview
Very Strong User
Hello Folks,
what are the benefits aeroic learned by bee'ing participated at the World Champs? In 2018 Kap Arkona's WorldChamp was found and the companys representative, the plane named redshift, partook. The designers perspective should be clear, pilot and weather did't suit the plane on demand. Or am I missing something more inside?
The overall outlay of this racing plane is quite different compared to other models in the F3B/F3F niche. It isn't good not to speculate about the pros and cons of the Redshift (or the airfoils, geometry and so on) in competitive flying. The concept seems (like others) scientifically bullet proof. The time is not ripe?
Of course it is not suitable to use the World Champs as a test bed. Because of this I'm interessted if it was able to collect benefits out of the competition for the Aeroic Racing Team?
What is the personal best of the Redshift?
Cheers Chris
what are the benefits aeroic learned by bee'ing participated at the World Champs? In 2018 Kap Arkona's WorldChamp was found and the companys representative, the plane named redshift, partook. The designers perspective should be clear, pilot and weather did't suit the plane on demand. Or am I missing something more inside?
The overall outlay of this racing plane is quite different compared to other models in the F3B/F3F niche. It isn't good not to speculate about the pros and cons of the Redshift (or the airfoils, geometry and so on) in competitive flying. The concept seems (like others) scientifically bullet proof. The time is not ripe?
Of course it is not suitable to use the World Champs as a test bed. Because of this I'm interessted if it was able to collect benefits out of the competition for the Aeroic Racing Team?
What is the personal best of the Redshift?
Cheers Chris
Doc James Hammond
Very Strong User
Hi Chris - I guess English is not your native language, right?
May I ask where are you from?
You sound an awful lot like someone else I know.
Anyway the Redshift has not been in many competitions as it only became available in August.:
But here is a post from Facebook:
Huge Congrats to John Phillips flying the Redshift in the English Open Eurotour International last weekend where he garnered fastest time:
As John puts it:
"39.22 in thermic air, open style turns as best I could...fast plane"
Attachments
purview
Very Strong User
Hello James,
No it is not a surprise. For me native sounds odd, by the way -> I am from Austria.
Yes internet and facebook isn't a liar. So real well done John Phillips.
Okay time is on your side. By 39.22 this is a mark.
Nowadays not in my range.
Redshift is still on top of my list. I know the behaviour of the wing planform and older aierofoils from yours.
Cheers Chris
No it is not a surprise. For me native sounds odd, by the way -> I am from Austria.
Yes internet and facebook isn't a liar. So real well done John Phillips.
Okay time is on your side. By 39.22 this is a mark.
Nowadays not in my range.
Redshift is still on top of my list. I know the behaviour of the wing planform and older aierofoils from yours.
Cheers Chris
