The Sheeks "Sea Vixen" is started!

This, hopefully, will be my Sheeks entry for the 2008 VSC XX.
Jack Sheeks has been very helpful, and patient with my questions.

The photos show the Trial Fit of spars, and booms.

With a close look, you will notice red line corrections to the drawing. The FM plans directory says the span is 56", the FM plan is 52.5". Jack confirmed the span is actually 56" and the plan is too small. We agreed on how to increase the span for an accurate reproduction of the airplane.

When starting the building I also found that the spar detail was drawn incorrectly. The spar tip height is correct, but the the spar height at the root is 1/4" too small. This is obviously a drafting error since the mistake is equal to the total height of the 1/8" spar caps.

At first I was concerned about the strength of the "V" configuration of the spars on the swept wing I-beams. But when the 1/8" ply "V" is added to the top and bottom of the spar. it is amazingly strong! The "V"s are flush with the top of the vertical spar and under the spar caps. You can the see the plywood "V" at the top of the spar.

If you are considering one of the swept wing I-beamers, this area is fine.

The bellcranks are part of the trial fit. The spar is built first.This takes time, so that the interconnect rods, will go though the spar with no binding. The interconnect rods and bellcranks required long slots in the spars, so I have added 1/4" wide, 1/16" ply spar triplers to the top and bottom of the vertical spar face in this area. If you look closely you can see them in picture #2. The triplers might not be necessary, but I will feel more comfortable with them.

I will be adding a 1/8" ply plate to the bottom of the spar to allow for a removable landing gear. This will replace the standard spar cap in the gear area. The bellcrank pivot bolts will be trapped by the same plate on the spar bottom, and a simple smaller plywood piece in the area as part of the top spar cap. The spar caps are not installed on the spar yet. 

The "Sea Vixen" requires a lot of forethought, but will be worth it. I have made mockups of the controls and the aft booms and rudders, to check for potential problems. I will show progress reports, periodically.

I have added photos of the only flight worthy "Sea Vixen"
This airplane was flown in Red Bull colors for a few years, and has just been repainted to the Royal Navy Colors. That is how I will paint it!

Tom, looking real good there. You've got the jump on me as I'm not finishd with the CAD work yet on the Torino. I am really looking forward to seeing more build pics as you go along.

Great start.

John Miller

Tom, Looks really great. After you posted this, I pulled out the plans I have for the SeaVixen. I can see what you're talking about, but how did you increase the span? Just pull it out or did you change the chord?

I'm considering a swept wing Sheeks plane for VSC. We'll have to see. Maybe a Swinger or Freedom 45 or perhaps the Scottsman. Hmm, a Knight?

Dennis I also have thought about the Swinger for a long time. The Body is hard to figure out from the plans. I sat down with Jack a few years ago and went over the plans with him. Its built with one body going into another body.The front extends to the back and the sides are added to the back 2/3. He said build it any way I want just to get the basic shape. His weighed over 60 ounces and still flew sort of OK. A lot of changes could be made to keep it light.He made a lot of notes on my plans.The one big change to all of his swept back wings is to move the leadouts back into the wing.Many had the front leadout coming out the leading edge. Move the bellcrank back near the trailing edge and run the flaps off the elevator pushrod.I can draw you a picture if you want. It is very easy to do and it gets rid of the swept wing problem of one flap moving more than the other.
Ed Ruane

WOW,
 Sounds like like we getting some serious interest in Jack's airplanes. I hope so.

Bill: Power will be a RoJet .40.  That's what I have been using in my "JD Falcon". I don't want to buy another engine unless I have to!

Jim: Yes my intentions are to paint it in the Royal Navy colors as in the above pictures.. BTW. that airplane has a very glossy finish!

Randy: Chord remains the same. The sweep dimension at the leading edge tip remains the same, relative to the root. Just project the tip section out spanwise. This changes spar lengths, and actual sweep angles. I am marking up the drawing as I go. I'll have to take a picture of the redlines at the tip.

You really have a lot of Sheek's airplane choices, maybe Robert can "Speed Build" a few!

Dennis: Yeah the spar is really bent, but not broke! Not only more bellcranks, but more horns and ball links too!

I hope you build the "Swinger" built. I'd love to see you at VSC.. it's been too long..about 35 yrs or more!

Ed:
GOOD CALL! like the B-57 Canberra night scheme - hhhhOT! 

I was thinking of something more like the OLD TF-Contender: white with red & grey trim 

BTW the your suggestion on flap horns was already in the bag, along with a SINGLE flap horn arrangement.  Just makes better packaging sense and better mechanically too.

Tom I was referring to the Swinger only

Here is the Sea Vixen as of today. It took wuite a bit of time to fit the bellcranks and interconnect rod. Much care is a must to assure free movement ina cramped space, before final installation of the I-beam.

Picture 1: Bottom with bottom ribs and booms

Picture 2: Bottom at fuselage root, and inboard bellcrank

Picture3: Shows inboard bellcrank, and the plate for the removable gear. The 3/4" rib in this area will be cut to allow for the gear cover, which will follow the contours with the booms.