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Aircraft Builder's Frequently Asked Questions
(Builder FAQ and How-To Section)

The FAQ section is intended to answer commonly-asked questions and provide a forum to share helpful techniques. While we obviously can't cover every topic here, we would like to hear from you on anything you wish to know. If it's of interest to others, the question and answer will likely be added here. Remember, there is no such thing as a dumb question, except the one that doesn't get asked... we're here to help. Send us your questions!

Currently showing the Skybolt / General Info category (last updated 10/26/04)
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  · Hale used to offer routed spars. Why are they no longer available?
  · Why are laminated spars stronger than solid wood?
  · What are the tradeoffs between built-up and routed-ply wing ribs?
  · What are the tradeoffs between aluminum and ply leading edges?
  · I bought a project and the fuselage is an inch shorter than the plans. Is this a problem?
  · Who is Steen Aero Lab?
  · When will parts kits for the Pitts Model 14 be available?
  · When will plans for the Pitts Model 14 be available?
  · I understand the Skybolt Radial drawings have been done for some time. It seems you guys are holding back on them. What's up?
  · What are the historical engineering changes for the original Skybolt?
  · Can the new three-piece wing be used with an existing Skybolt fuselage project or rebuild?
  · Can an existing upper wing be adapted for use in the three-section wing?
  · Can an existing wing set be used to construct a three-section wing for the Skybolt Radial having a 2250 gross weight?
  · What are the advantages of the new three-section wing for the Skybolt?
  · Can standard Skybolt wing wire sets be used with the Skybolt Delta or Radial.

  General Skybolt info
I understand the Skybolt Radial drawings have been done for some time. It seems you guys are holding back on them. What's up?

We have chosen to be selective in how the drawings are released. A number of sets have been given to seasoned builders who are committed to working with us through the details. The drawings are excellent, but subject to prototype issues which must be documented. There are many little gaps which could frustrate a first-time builder. These are being addressed as construction takes place. As the plans are perfected, they will be available for general release. If you are sincere and committed to building, and have some experience, please talk to us. It may make sense to have you join the collective effort. We are not trying to be restrictive. We are in this for the long haul.

What are the historical engineering changes for the original Skybolt?

Essentially there are three, and they were all done in the early years.

1) Forward Slave Strut

2) Landing Gear Geometry

3) Stretched Fuselage

Forward Slave Strut

The original upper aileron drive had the slave strut attached to the ailerons behind the hinge line. Early on, several incidents of aileron flutter were experienced. These were determined to be induced by a combination of backlash, lack of aileron system balance, and aerodynamic oscillation of the streamlined tubing slave struts in these specific constructions. The aileron system was redesigned to make it a lot more tolerant to play and imbalance by moving the slave strut attach points forward of the hinge line, thus the term "forward slave strut". It was also recommended that round tubing be used for the slave struts, or a spoiler ridge be added on one side if streamlined tubing is used, to prevent any periodic aerodynamic oscillations.

Landing Gear Geometry

The original Skybolt gear geometry was much lower with the wheels forward from the current location. This made full-stall landings impossible, and the forward cantilever component of the wheel position placed excessive torsion loads on the hinge bolts during hard landings. The wheels were moved aft, and the hinge bolts up-sized from 3/8 to 5/16. The new gear had superb ground handling characteristics. There is an easy way to tell if a particular Skybolt has the original gear (it is rare these days). If you are 5'10" or so, the spinner will be at chest level. With the new gear, it will be at nose level.

Another change to the gear was to up-size the wall thickness of the shock cord truss to .049. There had been instances of significant damage to the truss cross-member by the stop cables on very hard landings. Repeated dimpling and crushing of the cross tube by the stop cables eventually caused several truss failures.

Stretched Fuselage

To satisfy the 6-cylinder weight and balance envelope, the fuselage was extended three inches. The current fuselage length is 168 inches from firewall to tailpost.

We rarely see examples of these early features. Most of the existing Skybolt fleet has been modified and upgraded.

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