Cox Sky Cruiser

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Cox Sky Cruiser shown with its 2.4GHz transmitter and flight battery

The Cox Sky Cruiser is an RTF micro-sized R/C electric trainer/sport plane distributed by Cox Models, a division of Great Planes Hobby Distributors of Champaign, Illinois USA.

Construction is of Hobbico's "FlightFlex" foam. The material is quite flexible and the airframe will easily survive crashes that a beginner is likely to make. The wing is further reinforced by a carbon fiber spar; assembly consists of inserting the spar through a hole in the fuselage, sliding the wing halves over the spar and inserting them into the wing saddle.

Essentially a rebadged Nine Eagles Sky Runner, the 27.6" (702mm) wingspan Sky Cruiser resembles a glider or hotliner with its top-mounted motor and pusher propeller. No landing gear is fitted. The included 2.4GHz four-channel transmitter with its comprehensive LCD display flies the Sky Cruiser via rudder, elevator and throttle. Dual rates are selectable via pressing down on the right stick with the transmitter in as-shipped Mode 2 default. Pressing the left stick in Mode 2 places the transmitter in bind mode; no binding plug is required for the receiver since the process is automatic. The onboard electronics consist of a "brick" which incorporates the ESC, receiver and linear servos.

Like the Sky Ranger and Extra 300, the Sky Cruiser is equipped with the "SafeProp" propeller mounting system. This allows the propeller and spinner to pop free from their mounting hub in the event of a crash or hard landing, preventing damage to both the propeller and direct-drive brushed motor. The propeller/spinner are easily snapped back into place. Since the motor is mounted on a pod molded atop the fuselage, separation of the prop from the hub is rare.

Accessories include a lithium polymer balancing battery charger with AC adapter, 2S lithium-polymer battery, spare propeller, spare hardware, screwdriver and photo-illustrated instruction manual. The enclosed transmitter comes preset for Mode 2 control, but is easily converted to Mode 1 simply by removing the antenna hold-down strap from the rear of the unit, lifting and swiveling the antenna into the Mode 1 position and remounting it to point in the opposite direction. This procedure engages a microswitch which automatically switches the transmitter's controls and display, but it should be noted that the decals will appear to be upside down and the power switch will seem to be at the bottom left instead of the top right.

The brushed motor is replaced merely by unplugging its connector from the brick and sliding it out of its pod, but a "fishing line" should be attached to the motor lead before removal.

Care should also be exercised when handling the onboard electronics. If the servo gears are damaged, they are not available as a service part. Inquiries regarding replacement of the gears should be directed to Hobbico's product support department.

The Cox Sky Cruiser is recommended for ages 14 and older.

Flight characteristics

Although larger and heavier than the Sky Ranger, the Sky Cruiser boasts lighter wing loading and faster speeds with its larger motor. It is billed as a glider, but the rudder becomes ineffective without airflow from the propeller. Low-speed, near-zero thrust operation of the motor is sufficient if one wishes to "chase thermals." It is highly susceptible to wind and should not be flown when the wind speed is greater than 5 miles per hour (8km/h) since the model will be impossible to control. In calm conditions and under light throttle application, the Sky Cruiser is both stable and manueverable; low-altitude, high-speed passes are easy to perform.

Loops are possible if the airspeed is increased by first descending under power. Three-channel, rudder-steered operation along with a flat-bottomed airfoil make inverted flight impossible.

Since it is patterned after and marketed as a glider, it will glide for a long time without power. Landings are as easy as going out long on final and reducing throttle.


  • Wingspan: 27.6" (702mm)
  • Wing area: 87.9 in² (5.67dm²)
  • Wing loading: 5.4 oz/ft² (16.5g/dm²))
  • Weight: 3.3 oz (94g)
  • Length: 20.2" (515mm)
  • On-board electronics: Cox/Nine Eagles three-channel receiver/ESC/servo "brick"
  • Transmitter: Four-channel, Mode 2 2.4GHz spread-spectrum, switchable to Mode 1
  • Battery: 250mAh 2S lithium-polymer with JST connector and JST-XH balancing plug (COXA5805)
  • Motor: High-speed direct-drive brushed
  • Construction: FlightFlex expanded polypropylene foam airframe and spinner; plastic propeller and canopy; steel pushrods with nylon clevises
  • Typical flight duration: Ten minutes
  • Distributor: Great Planes Model Distributors, Post Office Box 9021, Champaign, Illinois 61826 USA
  • Catalog number: COXA6503
  • Recommended age range: 14 years or older
  • Skill level: Beginner; assistance from an instructor is recommended for totally inexperienced pilots
  • Available from: Any hobby dealer which stocks Hobbico/Great Planes products
  • Retail price (USD): $99.98

External links and references