Sweet Success, she flys awesome with this motor and fan but the 2200mah batteries get a bit hot. I am going to get a 4200mah battery and see if that helps. I got in about 5 flights with the Typhoon today and I moved the battery back on after each flight. She is still nose heavy but I still have some rome to move the battery back. I'll post the location of the sweet spot for the CG when I locate it.
CarreaGTSCS, this plane flys nose heavy with a 3s battery so I would be careful with a 4s battery in her. When this plane is nose heavy you have to but in a ton of UP elevator trim and she doesn't want to rotate on take off. The first flight today I had to come off the throttle when she hit top speed on roll out and than give full up and she popped into the air. If I didn't come off the throttle she wouldn't rotate and that was with the CG about 6 inched back from the leading edge where it meets the fuselage.

So did the 70mm fit fairly easy?

If so I think I'll eventually pop the lander alloy 68mm setup in there... there is a 4s and a 3s setup, the 4s has these specs:

Specs:
* Outside Diameter: 73mm
* Rotor Diameter: 68mm 5 Blade (fitted)
* Marterial: ABS & Special Aluminium
* Weight: 210g (Unit With Motor)
* Brushless Motor: 2838 (fitted)
* Motor Kv: 3,900 (revs per volt)
* MAX RPM: 48,000 - 50,000 rpm
* Max Power: 680 - 700W
* Static Thrust: 1050 - 1200g
* Current: 43 - 45A
* Required ESC: 50A (must accept 4S)
* Required Battery: 2500 - 4000 (use at least 20C. 25C Best)


the performance from that would be... insane... probably total overkill but it'd be fun to find out once i have mastered a more sedate power system. Apparantly they are excellent units, and sound amazing too.

re the rotate, it's a common problem with a lot of these jets and isn't necessarily a CofG problem... now that you have a higher power output it's probably even more pronounced due to the thrustline effectively keeping the nose pegged down that much more.

if you raise the nose gear slightly, and bend the mains forward a touch (both lowering the back and moving the wheels nearer the CofG then you introduce a better angle of attack and make rotate much easier. The technique you used is slightly risky in that you are popping up into a steep climb with no power momentarilly - the possibility is there for nasty things to happen.

Rusty just keep your eye on the weight with this bird, I'm going to try a 4700mah battery in her soon and I'll let you know how it goes.

Tarro what's yours weigh on 3s?

Mike

watch the weight but you're chucking a 4700mah in there lol...

Why do you say that by the way? Just from a cursory glance it seems quite light for the wing area, shouldn't suffer too much from a little extra weight as long as CofG is maintained and there's extra power to accomodate it. Of course out of the two of us you are the one who has flown it, so i'm interested in your reasoning.

Rusty thats why I said I'll let you know how it goes with the 4700 mah pack. I don't know what the weight is on my Typhoon but since I painted it and put the new 70mm fan in it just does not glide as well as I remember it gliding when I first flew it. Don't get me wrong I think it flys well it's just seems to come out of the sky a little faster and I have to add power right before she touches down to get it to flare. But I'm new to ducted fan planes so my opinion does count for much.

I've been doing a little research into the 4700mah packs and they weigh a TON, one of the guys I trust at the field said I would get a lot more out of the motor with a 4700 pack. The motor is pulling 45amps at WOT but the plane flys fine at a little more than 1/2 throttle. The HET 2W motor is not rated for a 4s pack I'm told.

Wonder what he meant by that... he could be implying that the battery voltage will be sagging under load. A good 2200mah at a true 25c should be able to cope though, also a good 2500mah at 20c would also do the job nicely. I don't think there's any need to go as high as 4700mah...

Rusty that's exactly what he said about the voltage, that it maybe dropping into the 10 volt range, I have to test it out today. I have a 2200mah 25c Thunder Power pack that got pretty hot, maybe I'll try a 2500 or 3000mah 25c next. I am happy with the power of the motor, she flys great at a little less than 3/4 throttle, I just don't like the batteries getting so hot.

yeah well you don't want the batteries to be operating too near their max c rating for extended periods for the best performance and longevity. Something like a 2500mah 20c/30c burst rhino lipo is pretty cost effective - that'd give you 6 amps headroom on max throttle even without the burst capability.

Rusty where do you get your Rhino and zippy batteries, I heard the zippy k's are good?

My Typhoon weighs 2 pounds ready to fly.

not much use to you i'm afraid - BRC hobbies in the UK has a good selection of zippy and rhino lipos at reasonable prices and they have great service so i just use them. I'm sure you can find them quite cheaply in hong kong though!

I picked up a 60amp ESC today and I mounted it in the rear of the Typhoon to help get this thing balanced. I checked the CG with 2200mah 20c battery all the way up front and the CG was at about 170mm. I figure with the 3300mah 25C battery I ordered from EJF I will have to move it back a bit. I am happy with how it is balancing out I just hope it's not to heavy. I picked up a lite weight wheel for the front LG which is bigger then the stock one so it lifts the nose up nicely for take offs.

Tarro Glad to hear she's flying well for you now. I just ordered a 2W for my Minifan to run on 3s here. Still haven't ordered the Eurofighter yet though. Before I order one I have to find out if any vendors at the NEAT Fair will be bringing any. If not I'll order one from Dean at EatSleepRC which is where I got my big Gripen. You can order the Rhino and Zippy packs from HobbyCity online. I ordered some 3s Packs last week.

Mike

The Typhoon flys great now even at 1/2 throttle and the CG is about 160mm back. I highly recommend putting the ESC all the way in the back of the plane it really helped balance it out.

Tarro, You would help a lot of us out if you could list your final setup. You have kinda been the guinnea pig and seem to finally be happy with your setup. Thanks, Chris

My set up is an HET 6904 70mm fan with a HET 2W motor powered by a rear mounted 60amp E-flite ESC with a 3s 2200 25c battery. It is very easy to make this plane nose heavy, you want the CG around the 170mm back from the LE where it meets the fuselage. Maiden your Typhoon a bit nose heavy (155 to 160mm)with some UP elevator reflex, 50% EXPO and 0 TRIM, this way you can add or remove some of the UP elevator reflex as needed. The UP elevator reflex is VERY IMPORTANT, when I maidened mine without it I almost crashed because full up trim was not enough for straight and level flight. Make sure the nose sits a little high when she is sitting on the ground, I put a larger nose wheel on mine. This makes her rotate MUCH BETTER, before I did this I had to punch it out and when she got to full roll out speed cut back the throttle and give full up and she would pop into the air. Now she rolls out and rotates fine. I put a square peice of thin plywood between the collet that holds the nose gear and the bottom of the fuselage, this helps distribute the shock of those hard landing and will keep the plastic piece that is mounted in the foam from coming loose. I used a long thin allen key for the top piece of the nose gear, it is the same shape and a little longer than the stock one but is a lot stronger.
My Typhoons flys at a little more than 1/2 throttle which is great for flight duration and battery life.
Good Luck

Tarro, thanks for all the help, glad to see it's flying well. I will be flying out of grass so I'll pro ably ditch the gear and belly it in! Thanks again, Chris.

fastcrash, fiber glass the front bottom intake of the fuselage, this will make it last longer.

how exactly do I do that? I am new to foamies. Can I glass it before its painted? I also have to find someone with an airbrush.

Dude get real you can pick up an airbrush for $75 and as far as glassing the bottom, just take the cloth and use water based Polyurethane.

I just tested my new Fullymax 3300 3s 25C battery in my Typhoon and here are the results. 62amp draw 665 watts, that should move her along nicely.

I finally got mine lol...

Built her up and maidened her today. She flies nicely but much slower than i was expecting. I wouldn't say it was underpowered but spent a long time at full throttle without much cause for concern... could definately do with more speed, maybe i shouldn't have fitted her with the armaments but they just looks so cool lol. Handles wonderfully though, very stable.

I found with the CG at about 160mm i needed almost 10mm of reflex trim. Thankfully i had already set a fair bit so it was within my trim range so could fly happily on the maiden, and now that i'm back from flying i've reset the trim and set it as reflex. I found 40% expo made her a very gentle bird to fly, will probably settle on 30% after a few flights.

I decided to make the top "spine" removable and that's let me sink the esc into the back there, just need to sort out some ventilation for it now. Also added a rudder though didn't get to test it much during the maiden.

She's now sat with a load of filler to fill up the cracks and gaps, started to sand it down then got bored. I'm thinking the paint scheme needs to be high vis because even on the gentle flight today it was hard at times to tell what way was up!