spacewalker SIGRC61, Building And Flying Instructions

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The general layout of the spacewalker (low-wing, open-cockpit taildragger) was inspired by a ride that Jessie had in a PT-19
years ago. Power is provided by a 65 h.p. Continential with it's cyliners hanging in the breeze like a cub. Even though it was
meant to be a personal airplane, public reaction has convinced him to market the plans and sell component parts through his
company, Country Air, Inc.
The classic lines of the Spacewalker remind most aviation enthusiasts of Pete Bower's Fly Baby or the Ryan trainers. One writer
even thought at first glance it was a Les Long creation of the Great Depression era. This is exactly the kind of feeling that Jesse
wanted to evoke with this design. With ultra-efficient, gas-sipping, cross-country machines dominating the homebuilt industry
today, it is strangely refreshing to see a brand new airplane designed solely for the pure pleasure of flight.
The Spacewalker fuselage is a welded steel tubing structure with wood formers and stringers in the turtledeck to give it some
shape. The wing is fully cantilevered with a massive center section main spar and box spars in the outer wing panels. Drag
loads are handled by diagonal compression trusses between the spars. The wing ribs are routed out of 1/4" plywood and the
wingtips are molded fiberglass. The tail surfaces are simple welded steel tubing. Jesse sells plans for the Spacewalker as well
as many component parts, including the completely welded fuselage frame.
When Maxey Hester (then Vice-President, Sig Mfg. Co.) saw a picture of the Spacewalker in the EAA magazine (Sport
Aviation), he decided that a model of this airplane would be the perfect showplane for his new four-cylinder O.S. Pegasus
engine. In December '86, he and Hazel Sig visited with Jesse Anglin and returned to Montezuma with a full set of plans for the
full-scale Spacewalker and announced that they were going to build one! After waiting many months to receive all of the
component parts from Jesse, work on the full-scale bird commenced here at the Sig factory. With much help from Dorothy and
Burnis Fields of Interlachen, Florida, Maxey had his airplane finished and ready to fly in twelve weeks! It was the first
Spacewalker, other than Jesse's, to be finished and flown.
Jesse Anglin has made many changes to his Spacewalker since it first flew.
Originally, only the rear set of tail brace wires were installed and the exhaust pipes
on the engine flared outward at the ends. Jesse said that the open pipes gave the
airplane a distinctive sound, but it was just too loud to live with. The pipes were
later routed into the cowl where they met at a centre muffler. Two more pipes route
the exhaust straight down out of the bottom of the cowling. Jesse also added
another set of tail brace wires to the front of the stabilizer at about the same time
the changes were made to the exhaust system. Several months later he changed
the shape of the windshield to improve the looks and wind protection. Also the
engine originally had no cylinder cooling shrouds, but after a long cross-country trip
in hot weather, he decided that they were needed. His latest change was to clip the
outer wing panels two rib bays on each side.
On the other hand, Maxey had not made any visible changes to his airplane - he
was happy with it just the way it was. More Spacewalkers were then being constructed all around the country. Most of these
would probably have some minor differences in appearance because most homebuilder's love to modify designs to suit their
taste. Maxey stuck very closely to the plans, so his airplane was almost identical to Jesse's except for the color of the paint!
About The Sig Model
The Sig 1/3 scale Spacewalker was designed with an eye towards scale construction techniques. The plywood ribs with
lightening holes, the box spar with laminated spruce caps, the detachable wing panels, and the open fuselage framework are all
copied from the full-scale bird. Most of the models built from this kit will end up weighing about 20 pounds, giving a wing loading
of 25.6 oz.sq.ft.
We are all very excited about the flight performance of the model. We've never seen an airplane with that long of a wing and
that much dihedral do rolls so axially. And according to Jesse Anglin, the full-scale Sapcewalker has the same trait. Loops,
snaps, spins, and inverted flight are all so easy to do. With 1800 sq.in. of wing area, landings are slow and stable. As for its
scale accuracy, it was designed using the full-scale drawings. This is one airplane that will definately put a smile on the faces of
scale and sport pilots alike!
Scale Data Sources
Builders that plan to enter their Spacewalkers in competition will need to collect some scale data on the particular aircraft they
have chosen to model. The following list of sources should prove helpful.