My flying buddy and I have been flying his flite streak for some time now.

If I may be so bold as to criticise a great design, but between us we can't get it to behave perfectly for the full schedule, it either flies great level (and doesn't do much else) or flies the manoeuvres brilliantly and is impossible to keep at shoulder height in level flight (upright or inverted).

As far as I can see the trim of the model is fine - insides and outsides behave the same, so I'm thinking that the problem is the stabiliser/elevator area - that it's too small for "precision" aerobatics, but just perfect for sport and combat. I did see a post about scaling up a streak to 45 size, and one poster recommended increasing the tail area by an extra few percent.

Don't get me wrong, I really love flying the streak, but what changes to the design (aerodynamics only) would people recommend for the 21st century?

I have a suitable motor (not an FP20) lying around and before I start cutting balsa what if any changes to the basic design can you guys recommend?

I have not noticed your problem with either Jr. or big Flitestreak.  I don't think it is due to a design flaw, but perhaps something peculiar to your situation. 

My Streaks also grooved well enough and flew smooth credible maneuvers. Are your controls binding? Something like a Primary Force might be more suitable for a serious step up. They point a lot better. Not much harder to build. No flaps.

Many have enlarged the stab and especially elevator, and report better control feel.  Some have made it much larger, like a doodlebog, but then it doesn't look like a streak.  One of the cool things about a streak is the rudder, stab and tip shapes.  You could tell Mr Aldridge had training in design.

If I were to do it ( and I have a lightening streak kit on the shelf)  I would increase the stab and elevator, especially the elevator chord.  If you want it to still look like a streak, just add another 1/2 inch to the stab chord.  The structure could use a little updating to make it easier to scratch build.  The tips could be reworked to make them easier to cover and add a adjustable lead out to, but that is about all.

I would dump the sheet spar use, and use cap strips like a lightening streak, longer motor mounts. and cut down the rudder.  It is about the right size for general fooling around with a 20-25 engine and it fits in the car well.  I would keep the 1 wheel gear. 


If you lengthen the nose, tail moment, and junk the flaps, change the tip shape of a streak you have a Sig Sky Ray.  If you want something to start with and modify, the skyray is a better choice.  More modern structure, longer moments and a modern control system.

They are very close.  Put the plans side by side sometime.

Dave

Thanks to numbers provided by Mild Bill Netzband, we have been building "Doodle Streaks" here in Southern California.  One even won a Profile 40 contest in the hands of Stan Tyler.  The stabilizer has about 4" more span, and 1/2" is added to the elevator.  The result is a model that turns easily but won't "bobble" coming out of a hard corner.  The elevator throw is reduced to match the added area and control power.  A longer fuselage wouldn't hurt, but a new stab and elevator are really a minor bit of work when throwing together an ARF 'Streak.

After watching Stan's model fly, Bill remarked "I'll be ***, it actually works!"