Modelfun2

My Feedback: (53)

I am currently building drawing a 27.3% and a 35% scale quickie. The airfoil is from the original 1/4 scale Quickie that was first published in Model Airplane News. The airfoil is all that is used from the drawings. History: This same drawings were then redrawn by another gentle man that started a company named Cressline and the sold to St. Crox, and now is FUSCO. To make a long story short or long the Fusco model (sport scale) is not to the current configuration that is flying (full size). So I decided to build a model the is very close to the actual outline; if not dead on from the actual full size drawings. And so here I am. I have the fuse built for the 35% scale version and the WS is 70 inches. The 27.3% version is at about 55 inches. I am limited on the ground clearance (the LG is the forward wing and upon landing the wing flexes). The Quickie needs a fuel pump also. I think I would actually like to start on the 27.3% just for the fact that there will be less $$$ involve in case of a mishap on the test flight. So I need around a .40 size engine with pump and a small enclosed muffler that does not swing a too large of a prop. That can carry the estimated weight of 6+/- lbs. The AC is very aerodynamic and does not need a lot of power. What two or four strokes engine would you recommend for the smaller size? I think a 10 to 11 inch max prop. Would the OS 52 work and/or is 70 too big. I know nothing about four stroke engines. I hope that this is not too stupid of a question. I just want other views.
Thanks!

Ralf Markwort

I would like to get some information from anybody who ever built and flew a Quickie. What are the flight characteristics, how is ground handling? would maybe the Dragonfly be a better choice? hope to hear from whoever reads this. Thank you. Ralf Markwort.

CafeenMan

I can't tell you much about the design, but a four stroke will need a high pitch propeller if the diameter can't be any longer. That means faster flight speeds and possible difficulty slowing it down to land.

Maybe a .46 with an 11-5 or 10-6 would be a good choice. A 10" or 11" pitch prop is good for 2-stroke .40-.46 engines.

Daren Savage

My Feedback: (6)

I had a sort of 1/3 scale (sort of because the builder used the 1/3 scale dimensions except for the fuse width, which was narrower than 1/4 scale!). Ground and flight handling were both excellent.

The only problem I had was the wire the guy used was too soft, so it tended to drag the wheel pants on those less than perfect landings which would result in a nose over.

The 1/3 scale was just over 9 pounds and flew very scale with a Saito 65 and an 11-9 APC prop.

I'm presently building an St. Croix 1/4 scale Quickie that I'll power with the same engine.

Camel65

My Feedback: (10)

You can always go to a multi-bladed ( 3-4 blades) prop as I believe the full scale required when the put larger engines like the 277 rotax or even bigger if I recall. The quickie is very efficent so if built light it should do well with the 46-52 size engine. Do you have plans you might be willing to copy? I would love to build a big quickie!

Regards
Bill

Modelfun2

My Feedback: (53)

I have looked at the Model Airplane News plans (which where the bases of the St. Croix and one other I can not recall). The full scale Quickie had a wing span of 200". So a 1/4 scale a/c would have a 50" main wing. All the models out there are not accurate. I have the actual plans (full scale) and access to a Quickie. This is where I pulled the numbers from. The "sport scale" kits or ARF 480 have a square fuse. The full scale is wider than it is tall. The fuse tail section is straighter and runs above the thrust line.

The St. Croix stated that the build up flying surfaces are better. NOT!!! This is why there was a lot of broken canards, since this is the landing gear also. the build up canard was not very forgiving on hard landings[:@]. The foam cores add a lot of strength. When sheeted and glassed around the joints, it was a better setup. This is why the Model Airplane New Quickie (Q1) is better than the kits, except that you have to make your own cowl and canopy. A pumped engine is very recommended because the tank is over the CG and the CG is critical for a canard aircraft.

The dragonfly which was designed by Viking Aircraft is a revamped variant of the Quickie (original Q1 a/c). Then came the Q2, Q200 and then the Dragonfly. The Dragonfly has a lot more wing area than the Q2. The Quickie was a single seat and really cannot be compared.

I have the plans to a full scale Dragonfly and will soon be working on a prototype which will be about 70" main wing. The nice thing about the Dragonfly is that it had three landing gear configurations.

TFF

If you join yahoo group cfair3 there are the full scale plans avalible. From what I understand, the real plane is a real handful in a crosswind and many were crashed because of the wide track gear; in the end, the fix was to make a normal width gear.

Modelfun2

My Feedback: (53)

I have full scale drawings of both the Quickie and the Dragonfly, and access to both full scale A/C. Thanks for the suggestion.

The issue with the standard landing gear (wheels on the tips of the canard) was that some of the taxi ways were not very wide and sometimes the wheels ran into the dirt. This in turn caused ground looping off the taxi way. In Europe the taxi ways are narrower than most of the USA airports (small airports).

This is why the Mk II came out with the LG attached to the inboard section of the canard. What is neat about this configuration is on the model you do not have to have such a strong canard. The canard in this configuration is flat on the upper surface andd the lower surface has dihedral created by the thickness of the airfoil. The Mk II is the model I am drawing up right now.

The Mk III is a tri-gear configuration.

As far as what I have gathered regarding the cross wind issue is there isn't any difference with a Dragonfly as compared with other conventional A/C. Just remember that with the very wide stance of the Mk I Dragonfly that if you were not centered (wing/canard over the blacktop) you would find yourself in the dirt when touching down. If there was a cross wind and you were "crabbing" it hard, make sure you get the nose straight before touching the wheels down! They have a neat device on the main wings ailerons that act like a reverse flap. This causes the wing to loose lift and sucks the A/C to the runway. Theya also have an optional speed break on the belly thatcan be installed. This is to slow the slippery A/C down on landing approaches. I believe that glide ratio is 17:1!

The wide stance allowed that A/C to be ground looped with out any issue of flipping the A/C. In fact this is a recommended move if you think you will not have enough room to stop before running off the runway! The ground handling is like a sports car!

With a model, none of the worries come into play. Usually the taxi ways and runways are wide enough. So what you get is a very good flying model that is quite aerobatic, but not 3D of course.