How runways are numbered? And more about ILS categories in India.

           

         

 Many of you guys are seen this type of numbers on the runways but you know the purpose of that numbers??  So here is briefing for that. So let's get started

 

This number are nothing but the magnetic heading of the runways or airplanes. Let's cover some basic topics first as we all know our earth is divided into geographic north and south poles. 

                 

Like this, there is nothing any instrument to find this  but earth is having it's own magnetic field which is always pointed to the North south directions.

If you  draw the straight line from the magnetic pole like,

                       

This , you can see that here is blue line is the magnetic north line and red line is for heading of the runway or airplanes. As you can see clearly marking on the runway is 08 that means runway is 80 degrees from the magnetic north pole.

 Then  you guys wondering why  the runway marking are always like r/w- 08, 07, 27, 18. Why not 084, 274 like this.

So here is reason for that if anyone says fly heading of 084 degrees it could leads to the misinterpretation between pilot and ATC so they always round figure the runway like runway-184 if we round figure it changes to active runway-18 

If any airport has two active runways then they are divided as runway-25R( right) and and another runway suppose r/w-18L( left).

Remember this are very important to find any heading for VOR navigation or to find out the runway locations for landing an aircrafts.

 If our magnetic heading of the aircraft is 05 i.e 50 degrees from the magnetic north pole then our airplanes tail always face opposite to +180 degrees like this.

                    

Then the other side of the runway number should be 50 degrees+180 degrees= 230 degrees then the opposite runway should be ruway-23. And also same for others heading also.