3D Hobby Shop 85" Katana - Assembly Thread

[sukhoi26mx]

more....

[sukhoi26mx]

more...

[sukhoi26mx]

Last two...

commentary and initial thoughts after the first flights...


As a reference point, I'm used to my 50cc airplanes coming in around 16 pounds (no fuel) up to 18 pounds. I've owned several airplanes in the 50cc size, and this one is the lightest by far at 14 lbs 12 oz.

Three flights in all this lovely day, and here are my results. The DL50 is a very solid engine, with easy starts, a solid mid-range, and a really hard pull on the top end. I hate to say this, but it feels stronger than my well broken in (100+ flights) DA-50R, which is absolutely amazing. I didn't tach it, but if I'm getting this kind of pull out - very strong - at 5500MSL, I believe this engine will be foamy-like for the Katana at sea level. Normally, I get a tractor like pull with only slight acceleration from the hover in my 50cc models, but the Katana with the DL accelerates rapidly in the vertical line and keeps going, which is unheard of at my altitude. Temped it after each flight, with none over 175.

Having flown and developed the 47" and 55" Katanas, and now the 85" Katana with Ben, we knew what the Katana airframe could do. Upsizing it has only improved already excellent flying traits. The first thing most modelers will note is the dramatically increased stability of this size model. It just points and goes, no drama. It also feels extremely light on the wing. Roll rate can be anywhere from extreme to sedate, and I settled right in the middle. With the CG on the aft edge of the spar fully fueled, the Kat took only a slight touch of down elevator, and after burning through a half tank was completely neutral.

Couple of quick notes from the first flight-

1. CG perfect with a half tank of fuel
2. No roll coupling in KE
3. very slight pitch coupling in KE (guessing a 3-4% mix)
4. Possibly needs 1/4 degree up thrust
5. Needs slight differential (couple of percent max)

I generally spend the first 4-5 flights trimming the model before I really let go, but this one was far too much fun out of the gun for that. I had casually mentioned to the peanut gallery that this was a maiden, and I do believe they think I'm full of $%&#, because by the end of the first tank I was hovering at eye level. The club I fly at generally frowns at 3D over the runway, but no one said a word today. So, a couple of airborne thoughts.

1. Inverted flat's are perfect flat with a steady three clicks of throttle and full opposite aileron.

2. Upright flat's require about 4-5 clicks of throttle and it seems to help if I modulate the throttle a little.

3. Harriers have only very light rock upright. Completely controllable with aileron, and by the second set of harriers was absolutely nailed. Rudder response is very direct.

4. Inverted harriers are rock-free.

5. Hovers/torques are almost hands off. I hate to give this away, but wait until you see some video. Easiest model I've ever torque rolled. Nail the vertical and watch it sit and spin.

6. Excellent punchout from the DL at 15 lbs fueled. Couldn't believe my eyes seeing it rock out of the hover. Just not used to that in the gas world at my altitude.

7. Precision tracking is very good, but all the precision I did today was on high rates so I was overcontrolling a little.

8. Points start and stop almost instantaneously.

9. Very sharp snap rolls. Easy to go waaaaaayyyyyy too deep in the snap, though. Note to self - set a snap rate elevator.

10. Rolling harriers have a linear roll rate with no snags (some models harrier roll rate snag a bit going through 3/4 roll point, slowing slightly) Very linear control inputs.

11. Mid range KE HA harrier is lacking just a little. The Kat fuse doesn't have a whole lot of side area, so it takes a bit of speed or a really high KE AOA (almost harrier)

12. Pitch rate is fantastic. Tight flips and waterfalls that stay close to heading with very little rudder.

Whew... More to come, but suffice to say that the 85" Katana is a really great flying model. Certainly turned a few heads at the field. Glad I waited for a good weather day, as it made for a brilliant flying session with a new favorite model.

Scott

[sukhoi26mx]

Just realized, I didn't post the exact specs of the model in the thread:

3D Hobby Shop 50cc 85" Katana
1340 square inches of wing!
(5) Hitec 5955TG servos
Smart-Fly Power Expander with flag switch
Smart-Fly Optical Ignition
A123 2300 mAh Li-ion receiver pack
1500 mAh NiMh ignition pack
Futaba PCM receiver
Completely stock hardware
Hitec 322 throttle servo
DL-50 gas engine with stock side dump muffler
Mejzlik 22x8 carbon prop
Tru-Turn Ultimate spinner
Stock aluminum landing gear
Stock Carbon wing tube
Stock Carbon stab tube
Stock Carbon Tailwheel


AUW 14 lbs. 12 oz.
Fuel fuel weight 15 lbs 8 oz. (550 cc fuel)

Scott

[sun.flyer]

Great thread Scott!!

There is no doubt that this is one sweet flying Katana. I have had the privilage of flying one of these on both a 12s electric setup and most recently on a Brillelli 50GT gas setup. Both fly the Katana with absolute authority and quite honestly it is hard for me to decide which power setup I like better. The Katana with 1340 sq.'s on the wing flies so incredible light that it really comes down to a personal preference as to which power setup to go with.

As Scott has shown in his thread the 3D Hobby Shop Katana comes with a very impressive compliment of hardware and with the light but robust airframe, carbon fiber wing tube/stab tube the Katana is coming in as one of the lightest 50CC airplanes on the market to date. A couple of additional nice features found with the 85" Katana's are:

- Preinstalled cowl ring (This allows for a near seamless attachment of the cowl to the fuse)
- Wing thumb screws (Both wings are held on to the wing tube/fuse by two thumb screws)

With the thumb screws it cuts field assembly time down to a minimium unlike some manufactures who also use additional clips/bolts to attach the wings.

The great thing about the 50CC line of giant scale airplanes is that for the most part they are much more convienent to transport than the larger 35%-40% which many require trailers to haul to the field. With the 85" Katana I am able to lower my back seat in my Ford Escape and take the plane to the field with only removing the main wings (stabs/elevators remain attached). This also allows me room to haul a 55" electric or two 47" airplanes with no problems. You got to love that!!

The 85" Katana is soooo incredible stable in both upright and inverted harriers that during the maiden flight I felt right at home bring it down on the deck hovering and flying harriers with it around the field. As someone had mentioned in a previous post the elevators are HUGE and extremely effective. But the great thing is that with the proper expo/throws setup on the Katana it can be flown with extreme precision or can be flown down low as a "3D Hucking Machine". This is an extremely versitile airframe and one that is getting quite a bit of airtime from me lately.

Great job to 3D Hobby Shop and all those involved in the Katana's development and implementation as the planes flight performance is only equalled by it's great looks.

Here are my electric setup on the 85" Katana:

Hyperion 5035-18 brushless outrunner motor
CC 110HV speed controller
(3) 4s 4400mah 3D Hobby Shop lipo battery packs (wired in series to make a 12s)
Xoar 22 x 10 prop
AR 7000 rx
Tanic 2700mah nimh rx pack

Watts = 3300W
Amps = 76A
AUW = 15lbs. 14oz.
Watts/pound = 207w/lb.

Here is my gas setup on the 85" Katana:

Brillelli 50 GT w/ stock muffler
Xoar 22 x 8
Smart-Fly Power Expander Sport
Tanic 2700 mah nimh rx pack
1400mah nimh ignition pack
AR 7000 rx

AUW = 15lbs. 7oz.

Here is a couple of videos of the 85" Katana in action.

Katana on a 12s electric setup
Katana on the Brillelli 50Gt gas setup

[davemilw07]

	Quote: Originally Posted by BaldEagel
	I did that with my Jamara Extra, it worked extreamly well, just make sure the distance between the attachement points on the servo arm and the rudder are the same, this will prevent any side load on the servo. Mike

Thanks Mike,

That's exactly what I had in mind for my Katana.

Ben, after I get the plane, I'll give you a call to get parts and discuss the best way to do the installation.

Dave

[3DHobbyShop]

Dave -

Sounds good, I was thinking of a single-sided installation, but a double would work, too.

We will be closed tomorrow for flying, but we'll be back in the office on Monday. Have a great weekend!

[davemilw07]

Tadaaaah, it's Heeeeeeerrrree..........

Congrats to Ben and Scott on a really fantastic looking model!! The pics are great, but you guys really have to see it for yourself.

Kudos on the triple-box packaging, it has saved the contents from major destruction. There were a couple of places where the fuselage box really got hammered, but the bottom half of the innermost box was completely unscathed. The glued-in cardboard tiedown straps didn't fare so well, however, so I'll talk to Ben on Monday to give him some feedback. All in all, considering the trip from China to Wisconsin, it's in virtually perfect condition.

Still finalizing the rest of my equipment, but at least in the meantime I can fondle the new toy (Am I still a kid, or what????? )

Till later, Dave

[sun.flyer]

	Quote: Originally Posted by davemilw07
	Tadaaaah, it's Heeeeeeerrrree.......... Congrats to Ben and Scott on a really fantastic looking model!! The pics are great, but you guys really have to see it for yourself. Kudos on the triple-box packaging, it has saved the contents from major destruction. There were a couple of places where the fuselage box really got hammered, but the bottom half of the innermost box was completely unscathed. The glued-in cardboard tiedown straps didn't fare so well, however, so I'll talk to Ben on Monday to give him some feedback. All in all, considering the trip from China to Wisconsin, it's in virtually perfect condition. Still finalizing the rest of my equipment, but at least in the meantime I can fondle the new toy (Am I still a kid, or what????? ) Till later, Dave

Dave,

Congrats on the new Big Kat!! I think we are all still kids at heart........we just have bigger toys now that's all.

Tim

[sun.flyer]

I hoping to get my Big Kat out today for some flying. It looks like the weather is finally going to cooperate.

Tim

[sun.flyer]

Here is a little video taken from today's outing with the 3DHS 85" Katana.

85" Katana Video

Tim

[gereco]

Hello, I write from Italy, they are remained fascinated from this model.
Someone knowledge where I can find the Katana 85" in Europe?
A salute to all from Sicily - Italy

[sun.flyer]

	Quote: Originally Posted by gereco
	Hello, I write from Italy, they are remained fascinated from this model. Someone knowledge where I can find the Katana 85" in Europe? A salute to all from Sicily - Italy

gereco,

You can actually order them from the 3D Hobby Shop website. Ben has International shippers available to send them to you.

Click here and chose the colored region you live in.

Tim

[gereco]

you have reason, thanks. I am putting myself in contact with they in order to see how much me cost the spediioni. Creed that I will buy it.

[sun.flyer]

	Quote: Originally Posted by gereco
	you have reason, thanks. I am putting myself in contact with they in order to see how much me cost the spediioni. Creed that I will buy it.

I think that means you are pretty interested in getting a 3D Hobby Shop Katana.

You can also contact Ben Fisher (owner of 3DHS) at ben@3dhobbyshop.com or for really long distance phone charges 1-830-990-6978. Hope this helps.

Tim