RE: Pica Duellist  
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RE: Pica Duellist - 9/24/2003 4:17:50 PM   
ChuckAuger



Posts: 5134
Joined: 12/5/2001
From: Pampa, TX, USA
Status: offline 		I'm running piped OS 46VF's on mine and I fly the heck out of it. I've never been concerned with stressing it out due to speed ( I do power dives at full throttle, 9 X 8 props turning a little over 17K on the ground) and never have had any flutter or problems. I have replaced the aileron servos about a year ago. This plane has been flying since July of '97, so it's got a lot of air time.

The thing I don't do are a lot of high-G negative manuevers and snap rolls are at pretty low speeds..it does an awesome avalanche.. the snaps are sort of delayed, but then it whips around very nicely.

I bet the ol' Duellist can take a little more. Full throttle straight and level at the very least!


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RE: Pica Duellist - 9/24/2003 7:22:00 PM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		Hello all, Don't know if you all will be mad at me, here's my duelist, I started it about two weeks ago, bashed it a bit, it's going as a tail drager, retract's in the nacelle's, and added 10 inches to the wing, shortened the tail end up about 4 inches, and two rudders setting right inline with the engines, hoping for alittle prop wash in an engine out situation, got two HB 40 PDP (black letters) to pull it around, let me know what you think, and do i still make it in the club,...........Paul

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(in reply to ChuckAuger)
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RE: Pica Duellist - 9/24/2003 8:49:00 PM   
William Robison



Posts: 20269
Joined: 11/10/2002
From: Mary Esther, Florida, FL, USA
Status: offline 		StrangeLover:

No argument with the wingspan, but the lengrth of the afterbody is one of the main things that makes the Duellist so forgiving with an engine out. Taildragger's fine, if you can find it there's a thread about a Duellist bashed to look like a WW II German twin engined fighter, also a tail dragger.

I like the HB engines, but do get them completely run in before you fly the plane. Inverted? I like them better on the side unless fully cowled. Just personal about the looks.

I've lightened your pictures and reposted them, and also a picture of one of the engine pair I have for the prototype Duellist 2/15. Guess what brand?

Bill.

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(in reply to ChuckAuger)
       Post #: 303

RE: Pica Duellist - 9/24/2003 9:08:07 PM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		Hello Bill, I am planning on fully enclosing the engines, got a lot of think through before any sheeting is going on, i'm planning on lowering the bottom of the nacelles, to hide most of the tires, not planning on gear doors though, thought i shortened the tail about 4 in. just looked and chopped 2 and 1/6 in. off, the stab. is mounted in the same location as the plans, just chopped the end of the fuse off so i can run a solid elevator all the way across, just easier,...............Paul

(in reply to ChuckAuger)
       Post #: 304

RE: Pica Duellist - 9/24/2003 9:16:33 PM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		Hello, Me again, can anybody tell me, does this plane build up nose or tail heavy? and how much weight does it take to balance? this just being built with the wood in the kit,.................paul

(in reply to ChuckAuger)
       Post #: 305

RE: Pica Duellist - 9/24/2003 9:32:42 PM   
William Robison



Posts: 20269
Joined: 11/10/2002
From: Mary Esther, Florida, FL, USA
Status: offline 		Strange:

Tends to build nose heavy. You have aggravated that by shortening the tail.

Problem with the stock kit was mainly not hollowing the blocks sufficiently. Be aggressive, when the blocks start getting transparent they're thin enough.

Alternately, make them of foam, put a single layer of glass on, then eat the foam out and use the shell you've made.

Another bit of advice - bring the wing and stab down to zero incidence, and bring the engines up to a zero-zero thrust line. Dave Platt, in his first revision of the plane did this on the Duellist 2/40 Mk II. All later versions, in all sizes, have been all zero-zero. Makes the plane like inverted flight a lot better. If you are locked in at the +2 incidence on the wing and stab, setting the engines at two degrees up thrust will accomplish almost the same thing.

If you make the single layer fairing blocks, be aware they will not stand up to abuse. Be a lot stronger, but close to twice as heavy, using two layers of glass.

Bill.

< Message edited by William Robison -- 9/24/2003 9:33:52 PM >

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Real Airplanes have Two Engines
AMA 25139 - More than 40 years.

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       Post #: 306

RE: Pica Duellist - 9/24/2003 9:47:18 PM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		Ok, You lost me on the fairing blocks, all ready built the nacelle's per plans 7 degree's down thrust, i almost built without,........crap! i'll have to think about this one, all's not lost, i do have a belt sander,......hmm,......elaborate on the fairing blocks please,...............paul

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       Post #: 307

RE: Pica Duellist - 9/24/2003 9:56:38 PM   
Stallion_51



Posts: 181
Joined: 7/10/2002
From: Tampa, FL, USA
Status: offline 		Yep..ours came out nose heavy also. Had to add some weight to the stab as shown in the previous pic. Also built the nacelle's with the 5 degrees of downthrust called for. They're a pain in the rear...for sure!

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       Post #: 308

RE: Pica Duellist - 9/24/2003 10:16:18 PM   
William Robison



Posts: 20269
Joined: 11/10/2002
From: Mary Esther, Florida, FL, USA
Status: offline 		Paul:

The "Fairing Blocks" I was talking about include the nose block itself, the main offender concerning balance, the blocks used to shape the nacelles, the wing tips, and so forth. Except for the nose block the real gain is less total weight.

If you do a good job hollowing everything, including the corner blocks of the fuselage, you can bring the stock plane in weighing less than 11 pounds. Most Duellist 2/40 planes of the first version weigh 12.5 pounds and more.

Another place to save a lot of weight is cutting the inside of the fuselage formers away, making them into skeletons. Don't go wild with F-1, F-3, and f-6 though, they are the main strong points for the nose gear and wing mounting. Problem is that most of the weight loss is in the afterbody, where you'll probably have to add weight anyway.

Another option is moving the firewalls back about 1/2" to 3/4" but be sure you can get your fuel tanks in before you do that.

With the firewalls already glued in, if you don't want to cut them free for thrust line alteration you can add a wedge between the engine mount and the exisrting firewall.

Just some things to think about.

Bill.


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Real Airplanes have Two Engines
AMA 25139 - More than 40 years.

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RE: Pica Duellist - 9/25/2003 2:15:47 AM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		OK, Bill, Got a question, How does the plane fly it built per plans? you know engines pointing down, wing and stab pointing up,............paul

(in reply to ChuckAuger)
       Post #: 310

RE: Pica Duellist - 9/25/2003 2:41:13 AM   
William Robison



Posts: 20269
Joined: 11/10/2002
From: Mary Esther, Florida, FL, USA
Status: offline 		Paul:

The original version of the Duellist is an excellent flying plane, it will do anything you ask it to. So long as you keep the cockpit on the sunny side. When you go inverted all the angles are working against you. Just by bringing the engine thrust line to plus two degrees, then with the wing and stab also at +2 the nasties are mostly eliminated. Granted the fuselage c/l will be pointed at -2 degrees to the aerodynamic center line, and you still have the washout in the wingtips, but it's a much more neutral flying plane.

So if you don't want extreme aerobatics you can build all the "Stock" angles and have a nice plane. I like to do high speed passes down the runway. Inverted. And I'm a lot more comfortable with everything at zero-zero. That's why all my early styled Duellists got sold. I still have one Mk I going together, but it's getting the Mk II tailfeathers and angles. And I have a complete Mk I wing I traded for, never had a fuselage for it. One of these days I'll get busy and make one.

Bill.




_____________________________

Real Airplanes have Two Engines
AMA 25139 - More than 40 years.

(in reply to OldRookie)
       Post #: 311

RE: Pica Duellist - 9/25/2003 4:05:24 AM   
strnglvr


 

Posts: 106
Joined: 2/13/2002
From: harrison, MI, USA
Status: offline 		Bill, Thanks, i see where your coming from, i just hated the thought of cutting the fire walls back out, but 0-0-0 it shall be, since i havn't built the wing sadle yet or nailed the stab down, this is the time to do it,........again thank you for your time,....i'll try to keep you posted,..................paul

(in reply to ChuckAuger)
       Post #: 312

RE: Pica Duellist - 9/25/2003 9:11:02 AM   
OldRookie


 

Posts: 654
Joined: 12/11/2001
From: Prior Lake, MN, USA
Status: offline 		I keep getting lost on the thrust angles.
First you are saying that the stab, wing, and engine thrust line should be + 2 deg.
Then you say to build it 000.
Why would the nacelles be at a negative 7 deg?
Aren't the nacelles the same angle as the engine thrust line?
I guess I'll have to get my plans out again and look.
I now have the Duellist MKII, and the Super Duellist kits. I am still going to build one of the TwinAir's first. I would like to get the 60 size that is coming out, but I still haven't gotten a response from several e-mails that I sent Northeast Aerodynamics. If the 60 size doesn't come out soon. I'll be getting the 40 size TwinAir.
Getting stoked!

Greg

< Message edited by OldRookie -- 9/25/2003 3:12:24 AM >

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RE: Pica Duellist - 9/25/2003 8:22:53 PM   
William Robison



Posts: 20269
Joined: 11/10/2002
From: Mary Esther, Florida, FL, USA
Statu