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FLYING SAFELY IS CERTAINLY VERY IMPORTANT The Primary Purpose of this Document is to suggest and describe why that if there is a need to bank an aircraft such as making it TURN or change direction maximizing the Bank of the Wing based on the planes current Airspeed. In other words LOWER FLYING speeds imply lesser angles of bank because the bank makes the wing think the weight of the plane has increased and therefore also mandates the minimum speed also needs to be increased.

Another way of stating is around 30 Degrees of bank while flying approximately 20% above the plane's minimum speed is typically not very if any risk other than accidently flying into another plane. BUT 45 Degree Bank or more is Risky.

AIRSPEED INDICATOR MARKED WITH A GREEN & WHITE LINE SHOWING PREFERRED AIRSPEEDS

 

In other words look at the Airspeed indicator and if flying without the Flaps down maintain a speed typically 20% above the speed designate by the bottom of the green ARC. Of course if the Flaps happen to be down then use the White ARC in place of the Green ARC. The bottom of the Green ARC is 160 so the minimum safe speed 160* 1.2= 192. Now obviously most aircraft used to learn how to fly have slower speed indications and this example is simply to show where to look the first time you get in the plane to fly it. As an example a small plane the bottom of the Green = 60 so the safe speed = 72. NOTE THIS PARAGRAPH IS NOT USING THE AIRSPEED INDCATOR SHOWN ABOVE

 

SThe Three different Bank Examples show the relationship of the weight the wing thinks it is supporting to Gravity and it will be defined that in general a 30 Degree Bank has little risk when flying and the 45 and 60 degree banks could cause serious issues.INE WAVE EXAMPLE TIME BETWEEN A&A 1/60th Second

 

Angle Lines on the Attitude Indicator look very near the same as yellow on triangles for 30 & 60 Degrees. The Yellow Line on 60 Degree Triangle is twice as long as the Blue Line. The 30 Dg Tri is 15% longer. In other words the Wing thinks the plane weight has doubled when the bank is 60 Degrees and is up 15% if the bank is 30 Degrees and is up 42% for the 45 Degree Bank. If a piece of paper is marked for the length of the yellow line and then located next to the blue line the difference can be observed.

Since the wing thinks the aircraft weight has increased its minimal or what is known as Stall Speed is defined by calculating the Square Root of "2"= 1.4142 or in other words if the minimum aircraft speed with the wing level is increased approximately 40% of if minimum speed were 60 MPH the new minimum or STALL SPEED would be 84 MPH.

Now if the Bank were only 30 Degrees the minimum Speed would increase about 7.5% [ Cos 30=.866]

One "1" divided by .866 means the wing thinks the aircraft weight is 1.1547 times what it is when the wing is level meaning 1500 * 1.1547=1732 so the Stall Speed is up approximately 7.5% or from 60 to 64.5 MPH. So if the aircraft in an airport area were flying 20% above its minimum speed a 30 Degree bank would not likely cause the aircraft to Stall.

 

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