The Helicopter Pilot
A helicopter was flying in a dense fog when it experienced a complete electrical failure.  The pilot brought the helicopter close to the ground when he spotted a large building.  He then flew up to the window where he saw a few people having some sort of meeting.  He quickly penciled the following message and held it up for the people inside to see.  
      

    Emergency - - Where am I?

 
 

The people inside the building responded with the following hand written message
 

 
Come back 
in 1 our 
  
 
The pilot could see that he wasn't going to get any help so he flew off.  However, the fog was very dense so he landed in a nearby field.  After discussing the situation with his passengers, he decided to wait for an hour and go back to the people in the building.

So after an hour the pilot returned to the building.  He was surprised to find that the room was now full of people.  Furthermore, there was a tripod with flip display board.  There was a nice cover sheet as follows:
 

 
 

 
 
 
Someone in the building flipped through the display as shown below:
 
      
     
You are 
     
 
      
in a 
 
 
 
 
helicopter 
 
 
 
The pilot immediately took out his map, glanced at his compass and flew to the airport.

Upon landing, the passengers asked the pilot how he had returned to the airport.

The pilot said, "All I needed was my location.  The people in the building were slow to respond to an emergency and gave a correct but useless answer.  The building could only be the Board of Education."