Typhoon CG, where it should be?
 

Got myself Typhoon, not 2x2 but 78 x73 with retracts.
Where CG should be? I'd rather have it a bit nose heavy.

Thanks guys.

on the tube.....
 

go to the back edge of the tube....I flew my 2+2's at about 5/8" behind the back edge of the tube.

you can play with it from there...but back edge of tube is a nose heavy position......

The way I checked my cg on th 2+2 was stick the wing tube in the fuse no wings....then stick the wing tube in a high point prop balancer....put a scale under the tail wheel and measure 2-3ozs on the scale....This was an easily repeatable number.....I always flew mine at about 3-3.5ozs.....but a couple others locally ran theirs at at about 2-2.5ozs.....


All the Typhoons fly about the same...even the Giles, 2000 and back to the 909....If you have about a 73" wing and full 2M fuse I think that's the "D" model it came between the typhoon 1000 and the 2+2....The 2+2, Giles, and 2000 are all the same basic wing.....Too Big....the "D" probably would be a good option in todays world as the wing is about 1000's sqs and not that big 1280 sqs or what ever the 2+2 has....


Typhoons are good planes....just can't keep up with the current F3A schedule....every thing Masters and below they are great.


Troy Newman

Typhoon CG, where it should be?
 

Troy, I'm getting ready to start on a Typhoon 2000, so your comment about the wing being too large is interesting to me (Gator R/C says the wing area is 1170 sq in). Would clipping the wing help or would that cause other problems? I would probably just take off the last bay near the wingtip, knocking about 6" off the wingspan (too much?)...best guess it would be a little under 1100 sq in taking that route.

Let me clarify that I'm really just getting started in pattern, but anything I can do to improve flight characteristics would be great.

Change the wing
 

The std wing will work well for you but it is just soooo stable....

take this with a grain of salt...

If I was building it for me....#1 you need to get foam cores..the Ribbed wing will be harder to build and get straight especially for a new guy....Nothing against your building skills...but I have been building and flying pattern planes for 15yrs and have had trouble doing accurate ribbed wings. Granted I'm not the best builder in the world...but I can make them look decent and they are straight!

Ok going to foam cores is a critical issue...make the wing more of a no brainer to get right.

That being said....I have some mods I recommend to you on the 200 specifically. We tested them and they work......

#1 the rudder has a big counter balance on it...This makes the rudder very effective...but also makes it act funny in rolls. Kill it.....Make the rudder have a straight hinge line and no counter balance just run it straight up

#2 Wing...I would change the wing slightly...less span is a good...maybe total in the 75" range.....and then move the tip rib template forward about 1.5"...this makes the wing a double tapered wing and will help the snaps....The less span will kill some sqs and help increase the wing loading.....Some of the foam wing cutters like Cajun and the Dunphys' at PAC can probably help you with the cores....I would keep the same ribs for the root and the tip just move the tip rib in closer to the root this would give less area.....another good option is stick a Hydeout wing on it...PAC now sells the hydeout kits you could get a wing from them...The Hydeout , Prophecy, Focus, Temptation, Sequel all have the same wing on them....its a proven wing...some guys will blow smoke in your butt that the ailerons are cut different so its really a xxxx wing....But thats a bunch of crap...same airfoils same plan form same wing! The Piedmont guys will tell you the same its the same stuff basically....just minor changes.

#3 one of the problems with the Typhoon's was a "nervous" tail. to plane would not lock on as well as it should have or could have...so a very good pattern guy Tony Frakowiak put a larger stab on the plane just blew up the dimensions by 110%.....this made the plane lock on better...but I think the result was with bigger tail feathers it made it even more stable.....I would keep the same stab if I had to do it again.....

Be very careful in your choices of wood...pick only the lightest stuff you can find. Order from a lonestar Balsa of similar and get the 4-6lb contest grade balsa...weigh it all and pick the lightest ones for your wings......These planes can easily(ty 2000's) hit or bust the 11lb limit especially when you built it all of wood from plans....Be careful not to get the weight too high. We made templates and cut foam turtle decks and belly's....this save a little time and makes a nicer product...Also Use covering Ultracote or Monokote. don't glass it and paint it...this make a weight gain of 4-8ozs even with the best of them doing the glassing work.....

With the change in the wing you are going to be a little tail heavy.....so don't stick the elevator servo or rudder servo in the tail end. Stick them up in the radio compartment under the Canopy....CG will be a little of an experiment since the wing will be changed a little...but calculate the 33% MAC and go from there....trimming will tell you what you need to do....

I really think these mods will make the Typhoon 2000 a really good flying bird....and modernize it. The wings on that plane were really the same all the way back into the mid 90's..I think it was too big then and really too big now....too stable...I know many will argue with me...but I have a ton of experience with the Typhoons and have flown many many many of them....Even took one to 4th place at the NATS in 99' The design is good...but like all things it has its quirks....If you make these mods you will no longer really have a Typhoon its really a different plane based on the Typhoon....There are several out there....The original Patriot looks a little Typhoon in its lines and roots...similar wing


This all being said...the stock Typhoons fly well. These mods will make them better. Depends on how comfortable you are with make changes.

I'm not knocking the designer of the Typhoons or even Gator for selling it that way...Its the way it was designed and works well. I think these changes will make it better. This comes from the experience I have gained in the past 4-5 yrs with the ZN and PL kits and also flying and playing with lots of different planes.

Advice is worth what you paid for it! Regardless of if you do the mods or not.....Use FOAM Cores for your wings and stabs....also try for the fin being foam...but if not you can build it up pretty easy.....Wings are easier to identical when they are cut from foam.....I know Cajun cut the wings, stabs and fins we used.....If you go with the PAC stuff just get Hydeout foam for the wings and stabs....and build you own fin or cut it from foam yourself....the fin is an easy one to do.



Troy Newman

Typhoon CG, where it should be?
 

Thanks for the excellent feedback Troy! I'm a pretty good builder (and really like to build), but foam is indeed easier I have to admit. I may buy a set of Hydeout foam cores from PAC for my Typhoon. (Hyphoon? Tydeout? :D ) I'll have to figure out what to do with the fin, probably end up building a balsa one from the Typhoon plans...

Thanks again!

Typhoon CG, where it should be?
 

Troy, perhaps a stupid question, but you mentioned the Gator wing is too stable and suggest going to a double-taper planform from the single-taper. Aerodynamically, doesn't moving the wingtip forward actually decrease the stall speed of the wing (e.g. stabilize it)?

Mind you, I'm not arguing with success, but something in the bowels of my dank and dusty engineering education is tickling me and I'm not sure exactly what it is...sorry, but it's the geek in me coming out. :D

stall speed
 

No in all cases does the moving of the wing tip forward reduce the stall speed. Depends on the wings aspect ratio for how it performs...The stall we are talking about in a snap is not speed related. Its an angle of attack causing the airflow to break or depart from the flow over the wing....

What you are doing by moving the wing tip forward and giving more taper on the trailing edge is making the wing act like a smaller wing.....also you are cutting the sq's down in size and this increases the wing loading.....

Aspect ratio is a huge contributor to the way a wing performs.....take a long wing like a sailplane...long wing small chord...Now take an aerobatic model..shorter wing longer chord...The long wing is not as good at rolls and snaps...but is really stable and good at lift and low on drag. The shorter wider wings are not as good at lift and have more drag...but roll and snap better.

I think the real reason the trailing edge taper helps snaps is it really helps the wing start flying again after it is stalled...and its easier to stall quickly. You have to remember that a wing section has turbulence off the back of the section...this disturbed air affects the way the wing performs....By putting some taper on the trailing edge it moves this turbulence forward and as a result of it makes the turbulence not come off the wing all at the same point...like straight TE....in stead the drag and the choppy air comes off the tip first and while its getting disturbed the root of the wing is still flying on the same air in the middle of the wing...I think this might have something to with it...also the wings seem to have less inertia....why this is I don't know...but they seem to start and stop quicker in the snap...

Snaps are not a function of airspeed to get the wing stalled.....The more airspeed the more elevator or angle of attack needed to get the wing to depart. But Aspect ratio of the wing is a big deal.

Troy Newman