Calibrating ESC and then using it
Used this code - 

/*
Coded by Marjan Olesch
Sketch from Insctructables.com
Open source - do what you want with this code!
*/
#include &lt;Servo.h&gt;


int value = 0; // set values you need to zero

Servo firstESC, secondESC; //Create as much as Servoobject you want. You can controll 2 or more Servos at the same time

void setup() {

  firstESC.attach(9);    // attached to pin 9 I just do this with 1 Servo
  Serial.begin(9600);    // start serial at 9600 baud

}

void loop() {

//First connect your ESC WITHOUT Arming. Then Open Serial and follo Instructions

  firstESC.writeMicroseconds(value);

  if(Serial.available()) 
    value = Serial.parseInt();    // Parse an Integer from Serial

}


the problem was when i was connecting the battery , it was not making any sounds...it was already calibrated by open pilot GCS so it was not calibrating again... i needed to reset the ESC and then run this program from arduino