PRINCIPLES OF FLIGHT THRUST AND DRAG CHAPTER 2 BLACKBURN BEVERLEY C1 JUST THINK OF THE POWER REQUIRED TO GET THIS AIRCRAFT FLYING.

THRUST TO PRODUCE LIFT THE WINGS OF THE PRINCIPLES OF FLIGHT THRUST TO PRODUCE LIFT THE WINGS OF THE AIRCRAFT MUST HAVE AIR FLOWING OVER THEM. THE AIRFLOW IS PRODUCED BY “THRUSTING” THE AIRCRAFT FORWARD. THE ENGINE OR ENGINES PROVIDE THE THRUST TO PRODUCE THE AIRFLOW. ENGINES PRODUCE THRUST EITHER BY A PROPELLOR SCREWING THE AIR BACKWARDS, OR A JET ENGINE EXPELLING AIR FROM THE REAR CASING OF THE ENGINE.

THRUST IN BOTH CASES, THROWING THE AIR BACKWARDS THRUSTS THE AIRCRAFT PRINCIPLES OF FLIGHT THRUST IN BOTH CASES, THROWING THE AIR BACKWARDS THRUSTS THE AIRCRAFT FORWARDS. NEWTON’S 3RD LAW EVERY ACTION HAS AN EQUAL AND OPPOSITE REACTION. THE THRUST ACTS ALONG A LINE APPROXIMATELY FROM THE NOSE TO THE TAIL OF THE AIRCRAFT. THE AMOUNT OF THRUST IS SELECTED BY THE PILOT.

CRASHING ! YOU NEED LOTS OF THRUST TO STOP YOU - PRINCIPLES OF FLIGHT THRUST CAN BE VERY IMPORTANT IF YOU FORGET TO PUT YOUR UNDERCARRIAGE DOWN. YOU NEED LOTS OF THRUST TO STOP YOU - CRASHING !

PRINCIPLES OF FLIGHT RIAT PRACTICE DAY

DRAG WHO RIDES A BICYCLE ? WHAT HAPPENS WHEN YOU INCREASE SPEED ? PRINCIPLES OF FLIGHT DRAG WHO RIDES A BICYCLE ? WHAT HAPPENS WHEN YOU INCREASE SPEED ? YOU GET MORE AIR RESISTANCE. THIS IS CALLED “DRAG” EVERY EXTERNAL PART OF AN AIRCRAFT PRODUCES DRAG WHICH RESISTS FORWARD MOTION. AS WE DID WITH THE CENTRE OF PRESSURE, WE TAKE THAT THE TOTAL DRAG OF THE AIRCRAFT ACTS ALONG A LINE FROM THE NOSE TO THE TAIL OF THE AIRCRAFT DIRECTLY OPPOSING THRUST.

DRAG THE GREATER THE DRAG THE GREATER THE PRINCIPLES OF FLIGHT DRAG THE GREATER THE DRAG THE GREATER THE ENGINE POWER IS NEEDED TO OVERCOME IT. MORE THRUST = MORE ENGINE POWER MORE ENGINE POWER = LARGER ENGINES LARGER ENGINES = MORE FUEL MORE FUEL = MORE WEIGHT THE AIRCRAFT DESIGNER IS RESPONSIBLE FOR DECIDING WHAT IS THE MOST EFFICIENT WAY OF ACHIEVING THE ROLE OF THE AIRCRAFT. WHAT CAUSES DRAG ?

Lots of drag and weight and not enough power, even with 8 engines. PRINCIPLES OF FLIGHT THE SPRUCE GOOSE Lots of drag and weight and not enough power, even with 8 engines. Only flew once and only to 10ft off the ground.

DRAG DRAG IS CAUSED BY THE SHAPE OR “FORM” OF THE AIRCRAFT PARTS. PRINCIPLES OF FLIGHT DRAG DRAG IS CAUSED BY THE SHAPE OR “FORM” OF THE AIRCRAFT PARTS. WHEN AN OBJECT MOVES THROUGH THE AIR IT LEAVES A TRAIL OF VORTICES AND EDDIES. AN EXTREME EXAMPLE OF THIS IS A FLAT PLATE. 90° TO AIRFLOW PARALLEL TO AIRFLOW

DRAG DRAG IS BEST ELIMINATED AT THE DESIGN PRINCIPLES OF FLIGHT DRAG DRAG IS BEST ELIMINATED AT THE DESIGN STAGE, BY HAVING THE LEAST EXTERNAL PROTRUDING PARTS AS POSSIBLE. BAGS OF DRAG

DRAG STREAMLINING THE FORM OF AN AIRCRAFT WILL REDUCE THE DRAG. PRINCIPLES OF FLIGHT DRAG STREAMLINING THE FORM OF AN AIRCRAFT WILL REDUCE THE DRAG. STREAMLINING MAKES THE AIRFLOW AS SMOOTH AS POSSIBLE AND REDUCES WAKE.

DRAG STREAMLINING CAN REDUCE THE DRAG OF A FLAT PLATE BY 95%. PRINCIPLES OF FLIGHT DRAG STREAMLINING CAN REDUCE THE DRAG OF A FLAT PLATE BY 95%.

Form Drag VERY TURBULENT WAKE REDUCTION IN FORM DRAG 50% 85% 90 - 95% PRINCIPLES OF FLIGHT VERY TURBULENT WAKE REDUCTION IN FORM DRAG 50% 85% 90 - 95%

DRAG IN A STREAMLINED FORM THE RATIO OF IT’S PRINCIPLES OF FLIGHT DRAG IN A STREAMLINED FORM THE RATIO OF IT’S WIDTH TO IT’S LENGTH IS KNOWN AS:- “THE FINENESS RATIO” DESIGNING THE FORM TO HAVE A FINENESS RATIO OF 3 OR 4 TO 1 KEEPS THE WAKE TO A MINIMUM. AS WITH LIFT THE AMOUNT OF DRAG VARIES WITH THE SQUARE OF THE AIRSPEED: 2 x AIRSPEED = 4 x DRAG 3 x AIRSPEED = 9 x DRAG

DRAG DRAG IN STEADY STRAIGHT AND LEVEL FLIGHT THRUST EQUALS DRAG. PRINCIPLES OF FLIGHT DRAG DRAG CofG THRUST DRAG EQUALS IN STEADY STRAIGHT AND LEVEL FLIGHT THRUST EQUALS DRAG. CofG DRAG GREATER THAN THRUST AIRCRAFT SLOWING DOWN IF DRAG GREATER THAN THRUST, THEN AIRCRAFT SLOWS DOWN. CofG AIRCRAFT GAINING SPEED THRUST GREATER THAN DRAG IF THRUST IS GREATER THAN DRAG THEN AIRCRAFT GAINS SPEED.

LIFT,WEIGHT,THRUST & DRAG PRINCIPLES OF FLIGHT LIFT,WEIGHT,THRUST & DRAG IN STRAIGHT AND LEVEL FLIGHT AT CONSTANT SPEED, TWO PAIRS OF FORCES ACT ON THE AIRCRAFT. LIFT OPPOSES WEIGHT AND IS EQUAL TO IT. THRUST OPPOSES DRAG AND IS EQUAL TO IT. LIFT WEIGHT DRAG THRUST

THE BLACKBURN BEVERLEY DID FLY PRINCIPLES OF FLIGHT THE BLACKBURN BEVERLEY DID FLY