Knife Racer 1m

The TJI RC Knife is a new 1m (39″) wingspan racer with brilliant performance. Good quality composite glass and carbon all molded model, good design, great price!

The pylon racer is very nicely molded with a strong wing spar and a massive battery compartment, which will allow 4S 2Ahr batteries, or even larger to be fitted with ease. Performance is very good, very straight at high speed, very nice high speed glide, and a reasonable landing speed with the flaps down. The aerodynamic shape is good. The model looks like a scaled up Sergey Sobokin Stinger Speed 400 pylon racer, which indicates a good heritage.

Note the Knife originally had centrally mounted aileron servos and was called Knief, but now has wing mounted servos and a less confusing name. 🙂

Some info on RCGoups here.

Knife Specifications
Wing span	1.00 m	39 in
Wing area	9.8 dm2	153 sq in
Length	64 cm	25 in
Flying weight from	550 g	19.4 oz
Wing loading	56 g/dm	18.3 oz/sq ft
Aspect ratio	10.2
Wing airfoil	7% proprietary
Dihedral (EDA)	1.3º
Spinner Diameter	38 mm
Battery compartment	approx 40 x 38 x 170 mm
Centre of Gravity	42 – 47 mm from wing leading edge
Controls	Elevator, ailerons, throttle

Knife Typical Weights
Wing	147 g	5.2 oz
Fuselage and fin	85 g	3.0 oz
Tailplane	17 g	0.6 oz
Accessories	17 g	0.6 oz
Total structure	266 g	9.4 oz
Receiver	6 g	0.2 oz
Elevator servo	8 g	0.3 oz
Aileron servos (2)	16 g	0.6 oz
Speed control	25 g	0.9 oz
Motor	74 g	2.6 oz
Prop & spinner	15 g	0.5 oz
Battery	140 g	4.9 oz
Flying weight	550 g	19.4 oz

Recommended Control Throws & Mixes
Elevator	3 mm up, 3 mm down
Ailerons	4 mm up, 4 mm down
Snap Flap	full up elevator -> 1 mm down flap
Landing mode	motor off -> 5 mm down flap

Recommended Servos
Elevator	KST X08, Blue Bird BMS-A10H, MKS DS75K, MKS DS6100, MKS HV6100, MKS HV6110, Blue Bird BMS-126WV, Blue Bird BMS-127WV
Ailerons (2 servos)	KST X08H, MKS DS75K, Blue Bird BMS-A10S, Blue Bird BMS-A10V

Recommended Powertrains
100 mph	Mega 16/15/3, 4.7×4.7 35A ESC, 3S LiPo, 350W
110 mph	Mega 16/15/2, 4.7×4.7 50A ESC, 2S LiPo, 400W
120 mph	Mega 16/15/3, 4.1×4.1, 50A ESC, 4S LiPo, 500W
130 mph	Mega 16/15/2, 4.1×4.1 60A ESC, 3S LiPo, 600W
135 mph	Mega 16/20/2, 4.5×4.5 60A ESC, 4S LiPo, 650W

Use Mega 16/20/2 or 16/25/1 for higher performace setups (Kv 3000 – 4500)