increase the gyro compass operating independently of the earth's magnetic field two way radio supplying direct contact between their artificial gyro horizon and let's see what happens the sound waves of your voice traveled out in all directions part of the sound waves hits the mountain and were reflected but just like waves are reflected by a mirror no suppose we wanted to play here this just we know that sound waves travel at about one thousand feet per second let's ring a bell and count the seconds until the echo returns six seconds which means that the sound waves traveled a total of six thousand feet and facts well the principle of radar is exactly the same but instead of using sound waves we use radio waves high frequency ones called microwaves knowing they are speed we can measure distances just as we did with your echo radio waves go fast very fast they travel at one hundred and sixty two course the control panel the antenna located in the nose of our plane is covered by a fiberglass shell called the radial the shell is transparent to our radar bea the scope contains a tool bike that used in television sets x is a screen on which we see our radar picture standard insulation provides to school one for the pilot and one for the copilot ok so how does it work well let's look at our parts and diagram for the synchronizer generates timing impulses called trigger pulses at the rate of four hundred a second these are sent to the transmitter and the skull both at the same moment the transmitter in turn sends a short pulse of radio energy to the antenna this paul's travels from the antenna along a narrow beam at microwave speed all round trip to an object one hundred and fifty miles away takes less than one five hundredth of a single second now let's get back to our scopes the scope translates this process into electrons which cause a small luminous spot to appear each new paltz is deflected so all that a steady flow of them keeps moving to the edge of our screen actually they move so fast that they create the impression of a single almost invisible line which is called the sweet now let's look at our radar antenna to see that reflected it's a giant addition of those found in flashlights and is used for the same purpose to concentrate our b this makes the beam pretty narrow all in order to get the greatest coverage our antennas turn slowly enough three hundred and sixty degree circle to sweep on our figure is coordinated with this so that all seems moved together once that dark wedge at the bottom that's the shadow cast by our airplane itself well what happens when the beam takes something up when something appears in our beam of microwaves are reflected back to the antenna then to the receiver and finally to our school the radar beam abas we are so matched that an object picked up by the beam appears in an exact relative position on the scope remember that our sweep line is continually revolving in time with the beam as it passes over the face of the school it literally paints a picture for the pilot to study or as we've been set so that the aircraft heading is always at the top of the screen now we add a grid for bearings and some range circles to help in measuring distances and our store completely ok this is all very interesting but what's the point i mean that how much good does it do rein well terrain mapping is one of the main functions of airline radar it's possible to tilt the radar beam up and down which helps to give the pilot a clear idea of the ground ahead of him regardless of the visibility conditions through which he's blind let's look at some actual radar pictures made during a pan american airways flight to panama we're approaching sandblast point lying over a solid layer of cloud direct vision isn't much help but the first sign of land appeared on our radar scope about a hundred miles off here we see sam blast on the fifty mile range twenty four miles out and sam blast point is clearly visible two minutes later we switch to a shorter range or a more accurate distance to sandblast point is now sixteen miles ahead and we're right on course the we can't be reached by the beam remains in shadow so our radar echo of a mountain peak would look like this now let's take a look at the most important views of right off its ability to map weather conditions our pilots try constant lay to give you the smoothest and most comfortable ride they can what a lot depends on the weather now thanks to radar the pilots can see storms long before they reach them and avoid them wherever possible this means more comfort for our passengers and a smoother ride than ever before what do you mean seen storms i thought you said radar cut right through clouds through ordinary cloud cover yes but areas with heavy rainfall cold fronts under storms the show up very clearly on the radar scope like this and this and this even a hurricane show up on our screen here's a recent one off cedar key i sure like to steer clear of that sort of wave and radar makes it easy now let's look at one more device called come to us this helps the pilots hold the center all the pilots cannot only see storms miles away but he can see into them i get what you mean now about radar being helpful let's listen to some actual comments by pan american almost indispensable on the lisbon jo'burg are out for command a saving in sign and a more comfortable flight terrific help in making a landfall approaching gander westbound radar is wonderful our flight was conducted with flying detours passengers enjoyed normal flying conditions and service whereas other flights in the area were getting plenty of turbulence think maybe i can see radar in action i have a live aboard that american is always happy to have its passengers visit the cockpit und