airbusdrvr

I will post some pics and progress photos as I attempt my first scratch build. This is the the late '50s Pegasus designed by Jerry Nelson. These pics are of the Pegasus built by a friend of mine back in the early 60s.

airbusdrvr

Here are the plans.

airbusdrvr

Searching for the right wood.

airbusdrvr

Starting the build.

airbusdrvr

In order to use CA hinges, I will modify the leading edge of the ailerons to use a Bruce Tharpe design.

airbusdrvr

Today's progress.

airbusdrvr

Some progress. The wings are basically finished. Will do the wing tip bows after wings are temporarily joined and ailerons taped into place. In this build, the top wing skins were installed last. That means I'm using wood glue to allow time to coat all the ribs and spars and be able to install the skin. The top rear half is installed and dried. Then I dampen the forward wing sheeting to allow it to more easily bend over the forward rib curve. When doing the second wing, I forgot the dampening step and installed a dry and somewhat stiff sheet. The sand bags were not heavy enough to press the sheeting down over the leading edge rib curve. The glue in applied, the sheeting has been pinned to the leading edge and now it can't be pressed down sufficiently to the ribs and top main spar. Yikes! To the kitchen for every can I can gather and stack them onto the wing for added weight. It worked-Lucky move.

The first picture here shows some of the wing changes I have incorporated that differ from the original plans.

airbusdrvr

A few more pics of the progress.

airbusdrvr

A couple more.
Oops! HOW did that poodle get on the counter?????

otrcman

Airbusdrvr,

I'm really enjoying your posts. In the early 1960's I built several Pegasus F's and it was my favorite airplane at the time. Only thing, I always chickened out and "flat-topped" the fuselage. This was a common mod and I only recall seeing one Pegasus with the beautiful curved upper fuselage and windshield. It will be a treat to see how you make that sharp curvature.

Do you have the stock dihedral in your wing? Looking back at old Pegasus pictures the original dihedral looks extreme to me now.

Keep up the good work.

Dick

airbusdrvr

I reduced the dihedral from 6 degrees to 3 degrees. As you know, gluing the wing halves together exactly right is a challenge during the 10 to 15 minutes one has when working with 30 minute epoxy. My wing halves went together great with one small exception. The wings are perfectly aligned front to back and the sheeting for each half aligns perfectly. However, when I removed the wing from the building board after the expoxy dried, I noticed the bottom seam for the wing halves was about 1/16". That means the dihedral is probably more like 3 1/2 degrees. But I think you are correct about to much dihedral when using today's radios. I wanted to keep the "Pegasus" look but not have an airplane that did not want to roll very well. One other change I am contemplating is to proportionately increase the vertical stab and rudder. The shape and look will not be changed, but I think I may increase the outline to give the vert stab and rudder a bit more effectiveness.

otrcman

I agree with your reduction in wing dihedral. By our standards today the original dihedral not only looks funny but also inhibits flying qualities.

Regarding increasing the size of the tail surfaces, there may be some subtle effects there. First, the overall size of the horizontal looks pretty good, but the elevators are (like most designs of the era) quite narrow. The reason for the narrow elevators goes back to the nature of the reed radios where you got full servo deflection every time you operated the transmitter switch. Smaller control surfaces were a way to smooth out the flight response and mask the limitations of the control system. With a modern proportional radio you can afford to make the elevators a greater percentage of the horizontal stabilizer.

Increasing the vertical stabilizer area may not be a bad idea either. A small vertical and high wing dihedral work in combination to make for strong spiral stability. Strong spiral stability (even if it compromised rolling abilities) was very desirable in the semi-free flight airplanes of the 1950's and early 1960's. But today we opt for better roll characteristics and don't worry so much about spiral stability. The larger vertical will work with the reduced dihedral to make your airplane less spirally stable and more apt to roll well.

Dick

airbusdrvr

I'm coming along with some of the tedious nose and canopy work. A lot of balsa block(later hollowed for lightness) and the rough sanding is completed.

airbusdrvr

I put most of the major pieces in place and got out my CG machine. The battery and elev/rud servos will have to go in the tail. I'm going to take a break from the build and get some other projects going.

boberos

Keep up the good work.
You will love this plane.
Mine flys great with no bad habits.
Maybe some who reads this will post a pic of mine from VRCS events or a mag article.

Bob G

mightyhorn

[8D]

Although I don't remember seeing one of these, I could have. When my dad was flying it was the late 50's/early 60's.
This is an awesome looking plane. I did notice that the tail, rudder and eitire wing look almost identical to the Sultan, Jerry's low wing plane that I have.

Where are these plans available?

Don Moore

billcarruthers

I am the friend that Airbusdrvr is refering to in the opening of this thread. I started building it in 1963, and went into 1964, it was over a year start to finish. Then I ended up going out of state (AL) to a school in Memphis. I never flew it. I worked for many years in the Homewood Hobby Shop where it hung for a while, and then I sold it.

Airbusdrvr is doing a great job on building the Pegasus, and I hope to be able to fly it when it is finished. I met him flying cargo planes in 1984 I covered the one I built with red silk, but I guess that is not done anymore. With his changes and the modern equipment, it should fly very nicely.

Bill Carruthers