Sport_Pilot

Don't say that! My mind kinda switch's off by that word. Which is why Iam totally lost when Itry to get %$#@!

crigotti

My Feedback: (3)

I noticed that Hobby Haven (Urbandale Iowa) has a Dirty Dirdy ARF on the shelf when I was in there this past weekend. Ask for Rick and tell him Crist Rigotti sent ya. $300

http://www.hobbyhaven.com/

jet22b

Hey Guys;
When test fitting the stabilizer to the fuse using the rods, did any get a 1/8" gap on both stab at the front. The back are flush on both side. Now if I put them on one at a time, one side will stay flush front and back, untill the other stab is put into place, than I get the 1/8" gap!!! Guess I must cut the rods some to make them fit right!! The wings are done!! Hobbico mechanical retract are in and working smooth!!
Sonny
aka
jet22b

doxilia

My Feedback: (3)

Kevin,

I'll be interested in seeing how you go about battery access. I thought that making a simple rectangular cut out of the canopy front end would be doable. It would require some "framing" in order to re-attach the canopy but it was cleverly done by Doug on a C4 recently. I though that a complete electric setup (e-tracts) on this bird could be fun option.

I guess I have a hard time seeing ARF's as anything but electric models..., my pitfall.

Have you given a try to higher kv motors able to produce the 1400W on 11-12" props? Again, I thought it might be interesting on this bird - 13K on a 12x8 or 14.5K on an 11x7.5... Something like that.

David

doxilia

My Feedback: (3)

Jason, looks like they will work nicely with minor modifications. 5 mm struts? What wheels and axles will you be using?

David

patternflyer76

Doxilla:

I plan on going through the retract area and making a cage to hold it right above the wing and against the servo tray. The servo tray is way off level to the control surfaces, which will not allow me to get my geometry correct. I will have to remove it, but I am worried about cracking the fuse if removed.

Kevin

JeffH

My Feedback: (43)

cut the cross pieces out of the tray first. Then use a dremel to grind the rails down to the 'glass if they dont pop off with some pressure.

SanJoseDale

Kevin, I am quite interested in doing one of these on electric. I never thought of inserting the battery there. Do you think there would be room to have an electric firewall mounted retract, and have enough room to slide the battery in?

Dale

Free Bird

My DB is almost finished. I usually don't follow the manual and jump around. Just need to attach the stabs and hookup the rudder and elevator, mechanical retracts are in and need to fit the cowl. Been a smooth build so far.

FB

patternflyer76

Yes, it appears so. I am not using the stock mount since it is for glow and I am installing a nose gear mount on the firewall face for my nose gear attachment. Also I am going with the fixed gear, so no worries there.

Kevin

SanJoseDale

cool, looking forward to your progress. I was surprised at your choice of motors. Wouldn't you want a much higher Kv? I found a Scorpion motor, which was designed to replace .60 glow, with a near 1000Kv, should move a pattern plane at 100 mph on 5S and an 11x8 prop. Gotta keep up with the Rossi's on a tuned pipe

patternflyer76

I fly SPA pattern, so tuned pipes are not allowed. This set up is as close as I can get to a .91 four-stroke, that is performance wise and it is very similar so not to allow an advantage one way or another.

Thanks:

Kevin

SanJoseDale

I see, I didn't think electric was allowed in SPA either? I would use this DB in our local "classic" contests, where pretty much anything is OK, just old, like me

MTK

Curious, are 4 strokes allowed in SPA?

When I flew Dirty Birdies in the late 70's I flew them on pipes. Is SPA legality cutoff before then? I don't know and am asking for what the rule sez

Ralph White

Well, Dave P.
Looks like I may not be running the OS 61 FR RE in my Dirty Birdy after-all. When running the engine today while adjusting the length of the pipe the engine started running poorly and would not idle. Upon examining the we noticed air bubbles in the fuel line from the pump to the carb. No bubbles anywhere else. We checked all fittings and none were loose. No holes in fuel lines. Managed to break one of the 90 degree fittings from the pump but replaced it with a standard fitting (6-40 threads).

Do you know if the pump starts pumping bubbles when they go bad? I'll bet they do. Guess I'll try a Perry pump. I've never used one but I want to be able to mount the 16 oz fuel tank close to the CG so a pump will be necessary.

If all else fails I'm going to put the NovaRossi in the Dirty Birdy. I would think the fuel draw will be okay if I get the tank within 3 inches of the firewall.

What's your opinion.

Ralph

AllTheGoodNamesAreTaken

My Feedback: (180)

Can't go wrong with the NovaRossi.

patternflyer76

Yes, electric up to 1400 watts/6s max volts/13.5" prop max diameter/must have external arming switch, four strokes up to a .91 and two strokes up to .61.... No pipes, oversized carbs, superchargers, retracts, flaps (unless on the plans) and prior to January 1st 1976 on design. The Dirty Birdy is a legal plane. The antique class is a little different.

Kevin

patternflyer76

c. Aircraft: A listing of known approved aircraft is available for Regular Pattern and
Antique Pattern. Any model which meets SPA standards is eligible, even if not on this
list. The contestant is responsible for documenting the model to SPA if it is not on the
list. Retractable landing gear is not legal. Flaps may be used only if on the original
plans.
d. Power: Both internal combustion (IC) and electric power are permitted in all
classes of SPA.
For internal combustion engines, a proper muffler must be used, but not tuned
pipes. Pumps may be used, but no air chambers or oversized carburetors are allowed.

Additional specific requirements by pattern event for IC engines are:
( 1 ) Regular Pattern
( a ) Any side exhaust two-cycle engine up to .61 cubic inches.
( b ) Any four-cycle engine up to .91 cubic inches with no air chamber
or super charging of any kind.
( c ) Any model aircraft designed and flown before January 1, 1976.
( 2 ) Antique Pattern
( a ) Any side exhaust two-cycle engine up to .61 cubic inches.
( b ) Any four-cycle engine up to .72 cubic inches with no air chamber
or super charging of any kind.
( c ) Any model aircraft designed and flown before January 1, 1967.
( 3 ) B-Novice Pattern
( a ) All age groups combined.
( b ) Any SPA approved airplane or any airplane with a wingspan of 72
inches or less, and using a four stroke engine no greater than .91
cubic inches with no super charging of any kind; or a two stroke engine
no greater than .61 cubic inches is legal to be flown in this class.
For electric power, the following rules apply: The intention of these rules
concerning battery voltage, capacity and wattage is to produce a verifiable
system that has capabilities similar to the internal combustion engines permitted
in SPA.
( 1 ) The highest nominal battery voltage will be 22.2V. For lithium polymer
batteries, this means a maximum of six (6) cells in series (6S) is
permitted.
( 2 ) The highest battery capacity permitted is 5200 mAh.
( 3 ) The original manufacturer’s label indicating voltage and capacity must
be attached to the battery and available for inspection.
( 4 ) A mechanism for disconnecting the battery power from the electronic
speed controller (ESC) must be provided on the exterior of the aircraft.
That mechanism must be clearly available, easily operated, and have
visually clear states. A simple example of the intention of this rule is a
plug that is visible and can be manipulated from the outside of the
aircraft.
( 5 ) No electrically-powered braking available or reverse torque of the
propeller is permitted.
( 6 ) The maximum power available to the motor is 1400 watts at any time
during the flight.
( 7 ) Electric power is NOT permitted in Antique classes.
( 8 ) No propeller larger than 13.5 inches in diameter may be used on any
SPA electric aircraft.

patternflyer76

More weights, motor mounting, rough cowl fit...

wildnloose

Care to share where you got your motor mounts from?? They are nice...

doxilia

My Feedback: (3)

Interesting cowl mods there Kevin!

You have to tell me where to pick up motor mounting hardware like that. I'm always cooking up something in the lab to attach motors. Actually, water plumbers tubing has come in handy... but only for the smaller guys. I'll need to mount a 25 size motor in the not too distant future (actually, one I already have but I'm not satisfied with my cooking job).

Aren't the bulkheads going to get in the way with your battery installation? They look like they have been glued in a little more permanently than factory (but maybe that's just the way they do it).

A magnetized cowl with a ply backplate seems like a clean and reasonably solid way to go. I saw it done on a Venus II to good effect.

David

doxilia

My Feedback: (3)

He, he... I guess I'm not the only one!

David

patternflyer76

Tower Hobbies has them. It is a GP product and they have them in different sizes as well. Part number

patternflyer76

The bulk heads are as they came, but they will be forward to the insertion point for the 6s.... I will be cutting the insertion point tonight. I will post some pics to show it better after the cut. I was surprised to see this style mount at Tower Hobbies. It said limited quantity so I scarfed it up ASAP...

Thank[8D]

Kevin

JAS

My Feedback: (2)

Well, with testing going to be done on the Phoenix, and other things coming up, this DB will need to find a new home. First to email [email protected] can get it. $300 plus shipping