MRC/Altech: EZ Stingray ARF

Model Airplane News, Jul 2001 by Onorato, Jim

MODEL AIRPLANE NEWS FIELD & BENCH REVIEW

Pattern flying by the numbers-easy as 1, 2, 3!

MRC/ALTECH

SPECIFICATIONS

Name: EZ Stingray

Manufacturer: OK Model Co. Ltd. Distributor MRC/Altech Marketing

Type: aerobatic pattern ARF

Wingspan: 52.4 in.

Wing area: 530 sq. in.

Airfoil: symmetrical

Weight: 5 lb., 8 oz.

Wing loading: 23.9 oz./sq. ft.

Length: 50.6 in.

Radio: 4-channel (throttle, elevator, aileron, rudder)

Engine recommended: .40 to .45 2-stroke or .50 to 70 4-stroke

Engine used: Enya 50CX 2-stroke

Street price: $269

Features: aerobatic ARF with triplelayer outer skin over inner wood frame; plastic cowl and clear molded canopy; all necessary hardware, including spinner, fuel tank, wheels and pilot figure, is provided.

Hits

* Excellent flight performance.

* Parts fit well.

* Easy assembly.

* Kit is complete.

Misses

Weak plastic clevises.

The EZ Stingray ARF is one of several in OK Model Co.'s popular line of ARU RC aircraft making its triumphant return to the U.S. market. These kits, known for their excellent flight characteristics, come 90 percent complete and feature a patented laminated skin over an inner wooden structure. The laminated skin consists of a plastic foam base, followed by a synthetic paper layer with the graphics printed on it and, finally, a layer of clear Mylar to protect the surface from fuel and cleaning products. This method of construction creates some very impressive graphics and results in extremely lightweight, excellent flying models.

like the other EZ ARFs, the Stingray features bright, colorful graphics, easy-to-follow instructions and nearly everything you need to get your plane into the air.

THE KIT

My first impression when I opened the box can be expressed in one word: "Wow." The Stingray is finished in metallic chrome, red and blue with white control surfaces. The graphics are typical "EZ" in that they are bright and colorful, and the chrome really stands out! The word "kit" is not quite appropriate when talking about ARFs, since you don't really build them; you just assemble them. This one is no different. Everything you need to get flying is included, except the radio, engine, fuel tubing and propeller. Even a pilot figure is included! Control horns, devises and other plastic parts are packaged on a molded "tree." Ailerons are already hinged and glued with very little gap. A fuel tank, plastic cowl, wheels, engine mount, spinner, pushrods, tinted canopy, pilot and complete hardware package (with metric nuts and bolts) are all included.

A 23-page instruction booklet guides you through assembly, eliminating the need for a full-size plan. The booklet is filled with excellent photos and adequate instructions in both English and Japanese. All dimensions are given in millimeters, which you can easily convert to inches by dividing by 25.4.

FLIGHT PERFORMANCE

The first flights of the Stingray took place on a sunny fall day with very little wind. I used the recommended throws for high rate and set the low rates at 60 percent. The initial flight was at low rate.

* TAKEOFF AND LANDING

I pointed the Stingray into what little wind there was and slowly advanced the throttle. The plane tracked nicely with just a slight tendency to turn left. A bit of right rudder straightened it out. When flying speed was attained, just a touch of up-elevator was needed to get the Stingray to lift smoothly into the air. Once in the air, a touch of down-trim made it fly straight and level.

The Stingray has a very shallow glide slope, which makes landings a real pleasure. I set up a long approach and throttled down to establish the rate of descent. While maintaining a nose-high attitude, I used slight up-elevator to bleed off some airspeed. As soon as the main gear touched down, I chopped the throttle and let the plane settle onto its nose gear.

LOW-SPEED PERFORMANCE

The Stingray handled very well at all speeds. When I forced a stall at a safe altitude, the tail dropped slightly and the plane just continued to fly. When it finally stalled, the stall was gentle and nearly straight ahead.

HIGH-SPEED PERFORMANCE

The Stingray flew really fast at full throttle and was very responsive to control inputs. The only problem that I noticed at high speeds was a slight tendency to roll out of full-up loops. The Enya 50CX provided more than enough power, taking it straight up without much effort. The Stingray's tracking made me feel as though I was flying a much larger airplane.

AEROBATICS

The Stingray is marketed as an aerobatic pattern model, and I was eager to see what it could do. I was not disappointed! I was pleasantly surprised at just how good this plane made me look. It performs graceful, large loops without losing heading, and its high-speed rolls are perfectly axial. With aileron throw at high rate, the rolls are so quick I wouldn't have time for elevator correction even if it were needed. Four-point rolls and snap rolls are very crisp. Inverted flight requires just a hint of down-elevator to maintain altitude. Sustained knife-edge is a breeze, as are outside knife-edge circles. Spins are fine, and recovery is immediate.