Ask Captain Dan: How Strong are Plane Windshields? – Our Resident Pilot Answers Flight Questions.

CFN – Pilot Dan Baz is answering your flying questions here on the Cornwall Free News.

If you have a question about flying you can email Captain Dan or post below.

Question

Big jets fly high and fast.  I always wondered what the windshields that the pilots look through are like on those airplanes .Question asked by Terry.

 

 

Answer

Windshields on large jet airplanes are pretty sophisticated parts .
.
Very different from automotive windshields.  They must withstand air pressure loads from outside as the airplane flies through the air.  These loads can be substantial when the airplane flies through the air at more than 700 kilometers per hour.  
.
Air pressure from inside of the airplane is also acting on the windshields, because  at high altitudes the cabin is pressurized .  The windshields must be strong enough to withstand an impact of a bird, the size of a seagull, should one get into the path of the airplane.
.
In addition to all this the windshields endure thermal stresses from temperatures at high altitudes as low as – 70 degrees Celsius to +50 degrees Celsius, when heated.  The windshields have a thin, tin oxide,  conductive layer in them. You can see right through it, but when electrical current is applied to this conductive layer, it heats the windshield.
.
The heat in the windshields is required to keep them from icing up when flying through precipitation at freezing temperatures.  Ice built up on the windshields would restrict pilots’ visibility.  For safety and redundancy, the windshields are constructed of two polycarbonate panes, each capable to withstand all of the loads and stresses.  The thickness of the windshields varies by airplane type, but is approximately 5 centimeters.
.

A bit more about Captain Dan:

Captain Dan Baz enrolled in Flight School at the age of 16.

He has completed studies in Aircraft Engineering and Master of Business Administration. He has been at the controls of many different types of aircraft, from single engine Cessnas to large intercontinental jets on global routes.

Over the last four decades he has flown thousands of hours up in the blue sky.

Have a question for the Captain ?  Send it to Captain Dan Baz    captaindanbaz@yahoo.com Every week a question from the readers will be selected and answer posted in this column.

Best Western Cornwall

Leave a Reply