How to use number keys as a throttle?

I would like to use the number keys 1-10 as a type of throttle. I have this working but I'm sure there is a more efficient way to do this without repeating code. Is enumeration the answer? Can't find a way so far to "enumerate" input. Am I thinking about this in a way that makes sense?

 public void getThrottle()
 {
 
 
     if (Input.GetKey (KeyCode.Alpha1)) 
     {
             // Setting throttle magnitude
         throttleSpeed = 0.0F;

             // Particle effects   
         engineFlames.Stop ();
         enginesOn = false;
     }
     else if (Input.GetKey (KeyCode.Alpha2)) 
     {
         throttleSpeed = 0.4F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha3)) 
     {
         throttleSpeed = 0.6F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha4)) 
     {
         throttleSpeed = 0.8F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha5)) 
     {
         throttleSpeed = 1F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha6)) 
     {
         throttleSpeed = 1.2F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha7)) 
     {
         throttleSpeed = 1.4F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha8)) 
     {
         throttleSpeed = 1.6F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha9)) 
     {
         throttleSpeed = 1.8F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
     }
     else if (Input.GetKey (KeyCode.Alpha0)) 
     {
         throttleSpeed = 2F;
         if (enginesOn == false)
         {
             engineFlames.Play ();
             enginesOn = true;
         }
             
     }
 }