This item is discontinued.

GREAT PLANES SPACEWALKER ARF
PRODUCT REVIEW
by Chris Chianelli

A FINE DAY AT THE FIELD ... GUARANTEED!

Flying R/C airplanes for 28 years has taught me two most important rules for staying happily enthusiastic about this hobby. First, always try new things to keep it fresh and exciting. Second, always keep a rock-solid flying airplane ready to go in the hangar in case that "fresh and exciting" project decides to do a wingtip dance into oblivion.

Crashes are all part of it, but they're a lot easier to laugh off if you always have a ready-to-go backup model on which you can depend to deliver some relaxed flying and a full day's fun at the field. What a great feeling that is.

In the old days, such confidence-building, fly'em-everyday-type models were usually nondescript sport designs of the Ugly Stik ilk. Thanks to Great Planes, today every modeler can have a gorgeous 1/4-scale Spacewalker as his very own easy flier in just a few evenings' worth of building. Moreover, not only is this model a well-finished and accurately built ARF, but it can also be legally flown at an IMAA scale meet! Some might disagree, but in my opinion, the hobby certainly has changed for the better over the years.

The first thing you need to know is that this 79-inch-wingspan ARF is 100 percent built of balsa and plywood and brightly covered with yellow and red MonoKote. The model looks as if someone really built it up in their shop. That's because someone did! The difference is, the shop this model was built in is way bigger than yours or mine—referred to by normal people as a "factory."

THE 'KIT'

The Spacewalker box is filled with hardware and accessories most modelers will find up to the task, including wheels, adjustable engine mount, tank and spinner. While all hardware and accessories served their function well, I like the model so much I think it deserves an aluminum spinner in place of the stock plastic unit. The same goes for the engine mount. This is a personal call, and I do tend to be a bit of an "old-timer" when it comes to engines and their support gear. One other note concerning the hardware: if you do intend to do the IMAA circuit with the Spacewalker, you might want to upgrade the 2-56 pushrods, clevises and control horns with 4-40 size units, as technically, this larger size is required by IMAA rules. Although I feel the supplied hardware is more than sufficient for this design, considering the 9.49 pounds of flying weight and 20 ounces of wing loading, sooner or later, you will run into an IMAA event safety director who will make an issue of it.

The cowl, wheel pants, and wingtips are all of vacuum-formed ABS plastic. I did reinforce the cowl at the screw hold-down points with extra Celastic that was supplied in the kit, and to this day, it shows no sign of cracking. (I've been informed by Great Planes that the cowl now comes reinforced with fiberglass.) Like the cowl, the wheel pants were also well formed with thick plastic and never cracked. The wingtips, however, are formed a bit too thin and did crack too easily on the first day of flying.

The main sub-assemblies of the Spacewalker—the fuselage, the wing halves and the tail feathers—are constructed of good- to excellent-quality balsa and plywood parts that are brought together with a high degree of craftsmanship. Just to give you an idea of the thought that has gone into this ARF: event he pull-through strings for pulling the aileron servo sires from the wing center section to the servo bays are already in place.

CONSTRUCTION

The word "construction" is totally inappropriate to use in conjunction with this model. The term "enjoyable assembly" is far more fitting. With the 24-page instruction manual and the 65 photos and diagrams found therein, it would be a waste of your time and our magazine space to walk you through a step-by-step building process here. Other than one area where I opted for a different method from the manual and one place I felt the sequence could have been better, I could never top the superlative job Great Planes has done on the instruction booklet. So what would be the point?

The area where my personal preference won out over the instruction recommendations was with the radio installation. With .90-size and larger models, I like to run each elevator half with its own servo and Y-harness them to the receiver the same as is done with the ailerons. About 15 years ago, I had an elevator servo failure on my 1/3-scale Christen Eagle. As luck would have it, I had each half of the elevator powered by its own servo, and the elevator half that remained functioning was sufficient to nurse the Eagle back for a reasonably uneventful landing. Ever since, I've opted for two-servo systems on both ailerons and elevator.

My only other departure from the instructions was the sequence for installing the landing-gear fairings. The instructions would have you install the fairings before mounting the main gear to the wing. I recommend doing it the other way around. The distance between the two pieces of music wire that make up the gear changes when they are placed in their respective landing-gear blocks. They have to be spread apart to fit in the blocks. Obviously, if you drill the holes for the fairing first, you're going to have to re-drill for a wider spread when you attempt to install the gear on the wing. Install the fairings after the gear has been mounted on the wing. Other than that, I followed the instructions to the letter, took my sweet time when taking measurements to square up the wing to the fuselage and the stabilizer to the wing and was rewarded with a scale beauty that flies straight as an arrow.

The specifications say the finished model will come out to between 8 and 8.75 pounds, depending on the engine used. I found this figure dubious, considering the size of the craft. Using O.S.'s latest pumped FS .91 4-stroke, my model weighed 9.49 pounds, including the 6 ounces of nose weight needed for proper CG location. This weight is still excellent for the model's wing area and gives forth a fantastic wing loading of only 19.97 ounces/square foot.

FLIGHT PERFORMANCE

I found myself at the field with my Model Airplane News associates Larry Marshall and Gerry Yarrish. When I announced the wing loading everyone wanted a turn at the controls. It was a sunny, cool, dry day - the best for flying alcohol-powered models! The wing gets optimum lift from that cool dense air and the engines optimum power from low humidity. Since we're all experienced pilots, I set up all surfaces for maximum suggested throw.

With the long tail moment and wide-track main gear, ground handling was excellent. While the included 2.5-inch wheels and axle location (about .25 inch behind the leading edge of the wing) might prove slightly problematic on rough grass fields, I managed on our average surface grass field just fine as long as I kept full up-elevator when taxing upwind and full-down elevator when taxing downwind.

Again, with the long tail moment take-off runs are very predictable and easy to control with this tail-dragger. Straight-ahead roll-outs are easily maintained, and all controls exhibited positive characteristics right from ground-break throughout a flat climb-out.

I know this might come off sounding cliched, but the Spacewalker really did fly right off the board, needing only slight down-trim and right rudder trim at the transmitter. No adjustments to the model's control linkages were needed. The wing saddle, stab saddle, fin slot and firewall are so accurately machined and assembled with this model that providing proper time is taken with all wing, stab and fin alignments and measurements as prescribed in the instructions, the model just has to fly true from the start.

After a few high-altitude figure 8's to make sure all was definitely well, it was down on the deck with some slow flybys. With its large size, bright colors and smooth response, the Spacewalker is a super confidence builder. Even with the slight gustiness that had set in with the onset of noon, landing setup and final approaches were rock solid, and the glide sink rate is comfortably shallow. With a 20-ounce wing loading on a model of this size, this should really come as no surprise. With the throws set at minimum, I'm convinced a young fledgling with good reflexes could learn to fly with this model—no problem.

As predictable as it is, the Spacewalker did hold a surprise: when the O.S. was leaned out a bit, it was time for some aerobatic barnstorming. Despite all its inherent stability, the Spacewalker would perform stall maneuvers whenever asked. Spins and snap-rolls are part of the Spacewalker's capabilities. If it's balanced even a bit nose-heavy, however, I'm sure this characteristic would disappear instantly. Mine was balanced exactly as per instructions. Another testament to the craftsmanship Great Planes put into this model is how little down input was required during inverted flight. To achieve this, great accuracy must be maintained with things like wing and stabilizer saddle machining. Personally, I like to fly my models with a bit of down-trim. I've always done this. It just makes a model feel more "groovy" to me. So when I flipped the Spacewalker onto its back, no down input was required at all during level inverted flight. This can mean only one thing: wing and stab incidence are dead on. End of story. Oh, yea, you can add engine thrust to that also, which obviously relies on proper firewall installation. You want further evidence? Rolls were very axial, needing only slight elevator correction.

Graceful Cuban-8's, hammerheads, stall turns and the like are all for the asking with this 79-inch wingspan bird. Of course, close in and low are what do it for me, and this big bright beauty is perfect for that kind of adrenaline-producing fun.

Right from the first flight, the Spacewalker was very relaxing to fly during the entire session—a total joy; well, except for one annoyance: Gerry Yarrish could do better-looking snap rolls than me. While Great Planes does state a maximum power of .91 4-stroke—and rest assured, the O.S. did a fine job—in my opinion, the airframe of the Spacewalker is big enough and easily strong enough for a good sport 1.20 4-stroke. Then it would be flying-circus time!

CONCLUSION

I really wish there were more ARF's in this size. When a model's wingspan approaches the 6-foot mark, it really starts to fly on the wing—very scale-like, yet you can still get it in the car!

With its fantastic flight envelope, the Spacewalker has to be one of the most versatile models around. Intermediate to advanced pilots alike would do well having one in their stable. No longer does that backup model have to be a generic ugly duckling. It can be a well-made, 1/4-scale, gorgeous Spacewalker. I'm already picturing how gorgeous mine is going to look on floats!