Modélisme par geeby22

 Extra 300 EP Ecotop 

Caractéristiques:

Envergure: 0.94m
Longueur: 0.76m
Surface alaire: 15.2dm²
Poids: 480 à 580g
Chare alaire: 31.6 à 38.2g/dm²
Profil: Bic. Symétrique

Analyse Motocalc :

MotOpinion - Extra 300 EP BMI 94cm Topmodel

Sea Level, 101,3kPa, 15°C

Motor:

Dualsky XM2830CA-12; 980rpm/V; 0,77A no-load; 0,132 Ohms.

Battery:

Dualsky 1300 GT (25C); 3 cells; 1300mAh @ 3,7V; 0,012 Ohms/cell.

Speed Control:

Castle Creations Phoenix 25; 0,0065 Ohms; High rate.

Drive System:

APC 9X6E (P Cont Corrected); 9x6 (Pconst=1,2; Tconst=1) direct drive.

Airframe:

Extra 300 EP 0.94 Topmodel; 15,2dm²; 586g; 38,6g/dm²; Cd=0,038; Cl=0,21; Clopt=0,44; Clmax=0,9.Stats: 227 W/kg in; 167 W/kg out; 8,6m/s stall; 12,2m/s opt @ 59% (40:06, 29°C); 18m/s level @ 84% (19:44, 38°C); 7,47m/s @ 37,6°; -1,49m/s @ -7°.

Power System Notes:

The full-throttle motor current at the best lift-to-drag ratio airspeed (11,8A) falls approximately between the motor's maximum efficiency current (7,9A) and its current at theoretical maximum output (40,5A), thus making effective use of the motor.

Aerodynamic Notes:

The static pitch speed (20,7m/s) is within the range of approximately 2,5 to 3 times the model's stall speed (8,6m/s), which is considered ideal for good performance.

With a wing loading of 38,6g/dm

², a model of this size will have trainer-like flying characteristics. It would make an ideal trainer, for use in calm to light wind conditions.

The static thrust (618g) to weight (586g) ratio is 1,05:1, which will result in extremely short take-off runs, no difficulty taking off from grass surfaces (assuming sufficiently large wheels), and vertical climb-outs. This model will probably be able to perform a hover or torque roll.

At the best lift-to-drag ratio airspeed, the excess-thrust (357g) to weight (586g) ratio is 0,61:1, which will give steep climbs and excellent acceleration. This model should be able to do consecutive loops, and has sufficient in-flight thrust for almost any aerobatic maneuver.

  Equipement :     

L'équipement provient de Hobbycity.

Récepteur Corona DS 6 Voies 41 MHz 4 servos 9 g HG202	Spec. Speed: .12sec/60deg Torque: 1.0kg Weight: 8.9g Size: 23x11.4x25mm
Moteur Turnigy C2830-1050 Moteur Dualsky 2830-CA12T Hélice APC E 9"x6" ESC Turnigy 18 A
Accus LiPo 3S 1300 mAh Loong-Max