New Typhoon MkII

[Hill Hobbit]

Typhoon 2? An interesting prospect,mmm.
As per Wayne, a Typhoon was my first mouldy back in 2010, when Rich at T9 advertised it for less than £300. My 2nd and current Typhoon has had 4 radios, 3 sets of fuse servos and Rx packs to date, and is about to have new wing servos and wiring. It has given 3 power pilots their first experience of sloping, and they might all fly nice mouldies now, but they all want to buy it. It ‘ain’t for sale though!
My thoughts:
A) 90 degrees of flap has always stopped it dead if needed even in less than 10mm headwind. Having the CG at 100mm really helps here. It’s rarely been ‘flown’ into land, but usually sideslipped in in a slow hover. So, I don’t feel the flaps need to be made any longer as it would reduce aileron length, but an increase in their chord would be a great idea. Look at Vlad’s Mini Graphite, the most amazing model to land I’ve ever flown.
B)Having a good 9g elevator servo in the fin, with the rudder servo up front, will be the way to go for a slope version, whilst for the electric, the option for rud/elev in the fin would remove the need for a built in servo location/possible breakage point behind the wing. So, having the option is a good idea, providing the fuz boom is probably made more substantial. As history has shown, this has always been the Typhoon’s nemesis…
C)Keep the flying surfaces virtually the same shape, if at all possible.
D) A ‘liftier’ aerofoil.

The original Typhoon flies so well, and is still popular. Heck, it was used years ago by TJIRC as the basis for their Dream (UK) or Alpha (USA) model. The wings, I think, are identical.

Wayne’s thoughts about the fuz would be a possibility, as after all, the original design has a 2 part fuz.

The best thing, IMHO, about the Typhoon, is it’s ‘chuckability’ when flown with only a little or no ballast. It can be thrown around without using too much sky, whereas more modern models are geared towards higher speeds and big, fast open aerobatics, like my beloved Forza.

Jonty

 

[Doc J]

Typhoon 2? An interesting prospect,mmm.
As per Wayne, a Typhoon was my first mouldy back in 2010, when Rich at T9 advertised it for less than £300. My 2nd and current Typhoon has had 4 radios, 3 sets of fuse servos and Rx packs to date, and is about to have new wing servos and wiring. It has given 3 power pilots their first experience of sloping, and they might all fly nice mouldies now, but they all want to buy it. It ‘ain’t for sale though!
My thoughts:
A) 90 degrees of flap has always stopped it dead if needed even in less than 10mm headwind. Having the CG at 100mm really helps here. It’s rarely been ‘flown’ into land, but usually sideslipped in in a slow hover. So, I don’t feel the flaps need to be made any longer as it would reduce aileron length, but an increase in their chord would be a great idea. Look at Vlad’s Mini Graphite, the most amazing model to land I’ve ever flown.
B)Having a good 9g elevator servo in the fin, with the rudder servo up front, will be the way to go for a slope version, whilst for the electric, the option for rud/elev in the fin would remove the need for a built in servo location/possible breakage point behind the wing. So, having the option is a good idea, providing the fuz boom is probably made more substantial. As history has shown, this has always been the Typhoon’s nemesis…
C)Keep the flying surfaces virtually the same shape, if at all possible.
D) A ‘liftier’ aerofoil.

The original Typhoon flies so well, and is still popular. Heck, it was used years ago by TJIRC as the basis for their Dream (UK) or Alpha (USA) model. The wings, I think, are identical.

Wayne’s thoughts about the fuz would be a possibility, as after all, the original design has a 2 part fuz.

The best thing, IMHO, about the Typhoon, is it’s ‘chuckability’ when flown with only a little or no ballast. It can be thrown around without using too much sky, whereas more modern models are geared towards higher speeds and big, fast open aerobatics, like my beloved Forza.

Jonty

Thanks Jonty.

By the way, since RCRCM has used the name "Typhoon this" and "Typhoon that" for quite a while, maybe to try to boost the sales of their other more mediocre models, so after a good hour of high-volume Bach this morning while I was working I decided to use the suffix "Toccata" to indentify the new plane.

Enter "Typhoon Toccata" And...I'm really happy to say that all of your comments have been taken into account in the new design.

To describe the new model, I suppose you could say that everything we have learned in the past 15 years has now been included in an all-new design, where virtually everything has been upgraded, but still keeping the character and looks of the old machine.

I.E.

• The fuse is the same shape and size except I have added 3mm diameter all over to the tail boom and also made all of the sections completely round so as to add strength and rigidity too.
• The nose will be a separate moulding bonded to the fuselage before shipping just like the orginal and in slope or electric versions.
• For the slope version, the slip-on nose stays as does the front moulded-in servo tray, but since the sections ar now all round, the inner nose moulding can be rotated to make it a bottom feeder if preferred - whether its top or bottom will be determined by testing.
• The old model shotgun ballast tube may still be used too.
• There is now a new servo hatch under the tailplane and I'll be offering a special dual servo tray to make a neat installation if needed, but the model can still be used with graphite push rods and those old but still good full-sized servos.
• The new aerofoil section will be the JH817 which is my best one yet for this application. It will accelerate well and move faster than the original section and also slow down better. Cl is higher and Cd is lower and the lift profile is pretty nice.
• Tails are now equipped with elevators and because of that are a slightly diferent shape, but still fit in with the general look of the model I think.
• Wing joiner is much larger (35 x 12) and can have ballast inside if needed.
• Wing shape is very similar to the original - just 'sanded' down a bit here and there to suit the new section. As with the whole model you'd have to put old and new side by side to tell the difference I think.
• Wing now has a sine-wave spar and so the torsional rgidity will be vastly imrproved, and also a ballast tube has been added.

I'm sure I could say that the construction and materials used will be far better than anything RCRCM have ever done too.

TJIRC Dream? Thats funny: Did you now that TJIRC actually asked me if they could use my design - copied from an aquired RCRCM model - to make the Dream? I said "Go ahead, maketh my day" I do so appreciate politeness (!)

I'm really hopeful that the Typhoon Toccata will exceed the performance of the orginal, and if I am right, then that might become a classic too in time.

Thanks again for the input mate.

J.

 

[agarchitect]

Sounds good Doc. We will need them in stock at Aloft a few weeks prior to get them ready for Sunset 2023

 

[Doc J]

Sounds good Doc. We will need them in stock at Aloft a few weeks prior to get them ready for Sunset 2023

Aha - another kind of Typhoon race?

Hmm..I like that idea.

Doc.

 

[agarchitect]

tocatta:
a musical composition for a keyboard instrument designed to exhibit the performer's touch and technique

An homage to the designer's touch and technique?

Typhoon 2
Typhoon 2.0
Typhoon 2022
Typhoon (squared) a little "2"

 

[Doc J]

tocatta:
a musical composition for a keyboard instrument designed to exhibit the performer's touch and technique

An homage to the designer's touch and technique?

Typhoon 2
Typhoon 2.0
Typhoon 2022
Typhoon (squared) a little "2"

Hey Adam,

tocatta:
a musical composition for a keyboard instrument designed to exhibit the performer's touch and technique...?

Would I ???

I think RCRCM have 3 kinds of Typhoon now, and two of them have nothing to do with me..

Typhoon Toccata! - try to forget it... its impossible. Eventually the Typhoon prefix will wear away and it will become Toccata. I love the Italian language - had you noticed?

Doc.

 

[Hill Hobbit]

James, a thought just popped up! The fin used to have a curved taper in thickness, which made the rudder hinge break at the top and bottom.
Please make it so that the rudder hinge area is flat along it’s length.

JT

 

[Wayne]

James, a thought just popped up! The fin used to have a curved taper in thickness, which made the rudder hinge break at the top and bottom.
Please make it so that the rudder hinge area is flat along it’s length.

JT

Good point! Seen that same issue with a few planes.

 

[Hill Hobbit]

My first Typhoon’s rudder hinge split at both ends before I even flew it…

 

[Doc J]

Good point! Seen that same issue with a few planes.

Thanks guys - will do!

Doc.

 

[Hill Hobbit]

Years ago, I never could understand why folks went thru hoops to cram the radio gear into their Typhoons. There were many pics on RCG back in the day that, to me, looked a complete mess. The first rx I used was a Spektrum 6250 (? not sure of the number tbh) which conveniently was the right width to fit between the rud/elev pushrods, so I cut out the semi circle seen in the pic. Doing so allowed the rx to sit on the flat area behind the servos, with the plugs and wiring aft. Initially the rx was installed with servo tape, then I swapped to beads of Uhu Por along the edges. Never had an rx move using this method.
3 different rx’s have since been installed, MPX, Jeti, and now a Frsky Archer R6 for my new x18s.

As the Typhoon has a vertical ply bulkhead positioned between the ballast tube and the top of the fuz, I am sure that’s gone a long way to maintaining the integrity of the nose section because the ballast tube crosses the fuz/nose section join.

I’ve installed vertical formers/bulkheads to ‘lock in’ ballast tubes and 2 part fuselages ever since, the latest being my Forza.

 

[SailHigh]

Hi Doc, one of the interesting "characteristics" of the Typhoon I've noticed over the years happens at high speed where she fish tails (yaws) side to side specially in a slight bank. Here we call it the Typhoon Wiggle. Maybe due to an undersized vertical area. While you are at it, please do increase that rudder area.

 

[Hill Hobbit]

Yeah, you’re right there Sean. The Typhoon’s wiggle at speed is quite noticeable, just like the old Phil Kraft KwikFli mk1 back in the day.
It was known as ‘The KwikFli dance’.

My Schwing88 didn’t wiggle, and my Forza definitely doesn’t. Must be a wallflower…

 

[Doc J]

Yeah, you’re right there Sean. The Typhoon’s wiggle at speed is quite noticeable, just like the old Phil Kraft KwikFli mk1 back in the day.
It was known as ‘The KwikFli dance’.

My Schwing88 didn’t wiggle, and my Forza definitely doesn’t. Must be a wallflower…

Wing shape, Lads.

Doc.

 

[Doc J]

Hi Doc, one of the interesting "characteristics" of the Typhoon I've noticed over the years happens at high speed where she fish tails (yaws) side to side specially in a slight bank. Here we call it the Typhoon Wiggle. Maybe due to an undersized vertical area. While you are at it, please do increase that rudder area.

See below, Sean.

Cheers,

Doc.

 

[Doc J]

Yeah, you’re right there Sean. The Typhoon’s wiggle at speed is quite noticeable, just like the old Phil Kraft KwikFli mk1 back in the day.
It was known as ‘The KwikFli dance’.

My Schwing88 didn’t wiggle, and my Forza definitely doesn’t. Must be a wallflower…

Hi Doc, one of the interesting "characteristics" of the Typhoon I've noticed over the years happens at high speed where she fish tails (yaws) side to side specially in a slight bank. Here we call it the Typhoon Wiggle. Maybe due to an undersized vertical area. While you are at it, please do increase that rudder area.

HI Lads,
This is an interesting story.

In a nutshell, the reason for this wiggly behaviour on the Typhoon MKI is the wrong wing planform shape. If the fin was a bit larger it might help, but the Typhoon Twerk would probably still be there from time to time.

At the time - in fact until last week (!) I was using the Elliptical lift theory as were most people I think, and to be honest when I designed the Typhoon I think the wind must have been in my brain as well as my arse - it certainly was howling outside (!) - Me being me, I simply drew an elipse to cover the aspect ratio of the Typhoon wing I wanted, then pushed the centre line back a bit at the tips to give a bit of aerodynamic sweepback and went with that. Seemed OK at the time, but its easy to be wise in hindsight.

What is causing the Typhoon Twerk (I like that) is a weird phenomenon where if the lift is not correctly distributed - especially if there is too much chord toward the tips - the model, if slightly provoked into a yaw in high speed flight can start an oscillation where the wings swap lift from side to side. In fact the fin area is fine - but its not quite enough to completely counteract the wiggle. The Sunbird has this problem too by the way, and frankly I think a lot of X-tail mouldies have it to a greater or lesser extent - not only my efforts. Even the world record holding F3f X-Tail model has this problem.

But anyway, as my old house master Jim Hazelwood would have commented:

Ignosce mihi quid fecerim ignoti - culpa mea.

But...life goes on and in between the Typhoon design and the last couple of years had been quite a long time for development, and I'd done quite a lot - although not for toy gliders - but the results were really interesting and indicated that the Eliptical theory, like walking on thin ice, was not all it was cracked up to be, which was really puzzling.

Later when I was designing the Corsa, a new 'hunch' SWAG theory had begun to form in my mind, and I daringly used it in the design of the new model. Tests showed that the wing shape was easily much better than the Typhoon - in fact performance wise it made the Typhoon look like a fat old lady. So I knew that I was on to something, but the problem was I didn't really know what.
I was a little bit afraid as hammered-in memory was telling me that the wings were now taking on a shape which according to 'conventional' thinking would make them highly prone to tip stalling, since the tips were getting smaller as the lift pattern was modified. But you can only imagine how happy I was to find that they didn't tip stall - in fact the new ones used on the Redshift, then Forza (Was Stormbird) and Sessanta seem to be the least prone to stalling that I have ever seen, so I was definitely headed in the right direction, but I was still not too sure why.

Then Epiphany! In a blinding flash it all came together suddently a couple of weeks back when Red introduced me to the NASA Paper on BSLD which study he had participated in. Bingo! the previously scrambled Rubic's cube began to organise itself before my very eyes into the correct colors in the correct places. I finally figured out what was going wrong in my original thinking - now almost two decades ago - and more importantly (always) that I was right in suspecting my own design methods.

On the new Typhoon Toccata, I have gone a long way towards a better planform, though I have not changed the wings to be completely formed as per the more modern designs I have done as Ilike the character of the older model, Nostalgia maybe, but I think I have done enough to kill the wiggle and give the new model a bit of a perfomance boost into the bargain.

So there you have it - who'd have though you'd have to think so hard to design toy gliders?

I think I'll post this on the Aeros thread as well since its probably quite interesting.

Cheers,

Doc.

 

[Hill Hobbit]

As the new model is going to cater for servo(s) in the fin, it will be thicker I imagine? Will the tailplane also be thicker in section?
I’m just thinking about the move years ago with pattern aerobatic power models from flat plate tail surfaces to fairly thick symmetrical sections for vertical fins and the tailplanes. Doing so (usually) smoothed out any wiggle (many of them did the ‘dance’) then, due to schedule changes, longer tail moments came into vogue. The combination of thicker, fully sectioned tail surfaces with longer moment arms resulted in models that literally flew as straight as arrows, and as smooth as silk.

I’m thinking that merely by having a thicker fin, the Toccata won’t exhibit any wiggle.

Any thoughts?

Cheers
JT

 

[Doc J]

Hi Jonty - more below

As the new model is going to cater for servo(s) in the fin, it will be thicker I imagine? Will the tailplane also be thicker in section?

Yes its 10% instead of 8% - I have been doing this for some years - ever since I found out that at least with my high response sections, the drag from a 10% section was actually lower than that from an 8% section. All my models including your Forza now use 10%.

I’m just thinking about the move years ago with pattern aerobatic power models from flat plate tail surfaces to fairly thick symmetrical sections for vertical fins and the tailplanes. Doing so (usually) smoothed out any wiggle (many of them did the ‘dance’) then, due to schedule changes, longer tail moments came into vogue. The combination of thicker, fully sectioned tail surfaces with longer moment arms resulted in models that literally flew as straight as arrows, and as smooth as silk.

Yep - but we do have to remember that there is quite a difference when you can't rely on a washing machine up front to drag the model around.

I’m thinking that merely by having a thicker fin, the Toccata won’t exhibit any wiggle.

The fin is also 10% and so It may help, but I did do the wing a bit anyway so it should be OK now. We'll see. By the way the fin hinge line is now straight too. Funny the things you miss.

Any thoughts?

Done deal dude.

Cheers
JT

Drawing is now finished but I'm still doing my usual week of 'eyeing' it to see if anything stands out. I've been thinking about this for a few years now so hopefully I have it sorted.

Cheers.

Doc

 

[Raymond Gaskins]

HI Lads,
This is an interesting story.

In a nutshell, the reason for this wiggly behaviour on the Typhoon MKI is the wrong wing planform shape. If the fin was a bit larger it might help, but the Typhoon Twerk would probably still be there from time to time.

At the time - in fact until last week (!) I was using the Elliptical lift theory as were most people I think, and to be honest when I designed the Typhoon I think the wind must have been in my brain as well as my arse - it certainly was howling outside (!) - Me being me, I simply drew an elipse to cover the aspect ratio of the Typhoon wing I wanted, then pushed the centre line back a bit at the tips to give a bit of aerodynamic sweepback and went with that. Seemed OK at the time, but its easy to be wise in hindsight.

What is causing the Typhoon Twerk (I like that) is a weird phenomenon where if the lift is not correctly distributed - especially if there is too much chord toward the tips - the model, if slightly provoked into a yaw in high speed flight can start an oscillation where the wings swap lift from side to side. In fact the fin area is fine - but its not quite enough to completely counteract the wiggle. The Sunbird has this problem too by the way, and frankly I think a lot of X-tail mouldies have it to a greater or lesser extent - not only my efforts. Even the world record holding F3f X-Tail model has this problem.

But anyway, as my old house master Jim Hazelwood would have commented:

Ignosce mihi quid fecerim ignoti - culpa mea.

But...life goes on and in between the Typhoon design and the last couple of years had been quite a long time for development, and I'd done quite a lot - although not for toy gliders - but the results were really interesting and indicated that the Eliptical theory, like walking on thin ice, was not all it was cracked up to be, which was really puzzling.

Later when I was designing the Corsa, a new 'hunch' SWAG theory had begun to form in my mind, and I daringly used it in the design of the new model. Tests showed that the wing shape was easily much better than the Typhoon - in fact performance wise it made the Typhoon look like a fat old lady. So I knew that I was on to something, but the problem was I didn't really know what.
I was a little bit afraid as hammered-in memory was telling me that the wings were now taking on a shape which according to 'conventional' thinking would make them highly prone to tip stalling, since the tips were getting smaller as the lift pattern was modified. But you can only imagine how happy I was to find that they didn't tip stall - in fact the new ones used on the Redshift, then Forza (Was Stormbird) and Sessanta seem to be the least prone to stalling that I have ever seen, so I was definitely headed in the right direction, but I was still not too sure why.

Then Epiphany! In a blinding flash it all came together suddently a couple of weeks back when Red introduced me to the NASA Paper on BSLD which study he had participated in. Bingo! the previously scrambled Rubic's cube began to organise itself before my very eyes into the correct colors in the correct places. I finally figured out what was going wrong in my original thinking - now almost two decades ago - and more importantly (always) that I was right in suspecting my own design methods.

On the new Typhoon Toccata, I have gone a long way towards a better planform, though I have not changed the wings to be completely formed as per the more modern designs I have done as Ilike the character of the older model, Nostalgia maybe, but I think I have done enough to kill the wiggle and give the new model a bit of a perfomance boost into the bargain.

So there you have it - who'd have though you'd have to think so hard to design toy gliders?

I think I'll post this on the Aeros thread as well since its probably quite interesting.

Cheers,

Doc.

Doc,
This is quite illuminating and something I was completely unaware of (forgive the dangling participle)):
Raymond

 

[Konrad]

Wing shape, Lads.

Doc.

Hum?
With regards to the Phil Kraft KwikFli mk1 wiggle. I recalled that this was a problem on the down line coming out of a wing over or Hammer Head. The yaw oscillation (wiggle) wouldn’t dampen until the start of the pull out. The fix was to hold (load) the rudder a bit on the down line. My Phil Kraft KwikFli mk1 used a single aileron servo with aft placed control horns for a lot of mechanical differential . I don’t recall too much wiggle on the high speed passes.

Back to the Aeroic wing. All my Redshifts will wiggle in yaw rather badly at times, like doing a hammer head. But at speed in a shallow dive ( like a CG test) the Redshifts will oscillate in yaw a bit when upset by say turbulence. In level high speed flight this actually becomes rather noticeable. The older wing of my Schwing Corsa 108 can result in much the same oscillation coming out of a hammer head. But in straight line speed runs the oscillation is minimal.

So it would look by my experience that the older Schwing wing to be more stable in yaw than the newer Redshift’s wing. I don’t believe this to be true.

In my fleet of moldies the Sanda Mach 2.4 and 60” Flash 2 shows this wiggle the most. While my large tailed Freestyler-5 hunts the least. I’m of the opinion that this behavior is closely tied to vertical fin area rather than lift distribution. I point to the fact that the Freestyler is more stable than the Redshift in high seed dampening of yaw. I think the Redshift has a better wing than the Freestyler-5, but it is system synergies that make a great ship.

40 years ago I tried working the Bell shaped lift distribution into my quarter midget racers. The results were less than stellar.

Doc, if trying to work this latter Prandtl theory into a new wing I’d strongly recommend doing some test articles with CNC cut foam before going through the expense of molds. I wish you all the best in that endeavor.

Sorry I missed it but why gold plate this antiquated design? As I recall the 2m Stormbird out flew the Typhoon in all conditions other than real light lift. In light lift the cheeper Obechi covered foam ships have that segment of the market. I don’t see where the market needs another Typhoon. A nice modern 2m yes, like a revamped Stormbird, not a revamped Typhoon. But what do I know about market demands!

And please set up all live hinges to be linear in all three axis. This is a bit of a problem with my Schwing Corsa 108. The rudder hinge on the bottom is impinging on the lower fuselage radius.