FIGURE 1.Coordinated Turn Nomograph. By drawing a straight line between any
                    two items, the third feature of the turn can be determined.

With any two features the third can be determined for full-size as well as any selected scale-size model or maneuver we might wish to compare. If we use a 35 degree bank-angle example for a full-size general aviation aircraft flying at 100 mph (or 146 ft/sec), we can easily find it will turn in a radius of 955 ft. This is simply done by drawing a line between the 35 degree bank angle on the left to 100 mph in the middle and then extending the same straight line to the right side of Figure 1 for turn radius. The same 35 degree bank angle can then be used to also find the correct speed for a scale-size turn of 1/5 radius (955/5) or 191 feet to show a model speed of 44.7 mph (DSS). If we try to fly at a scale speed of 100mph/5 or 20 mph for this same scale-size radius of 191 ft, we can verify the earlier described unrealistic 8 degree bank angle occurs from this nomograph.

Further benefits exist from Dynamic Similitude Speeds when compared to slower scale speeds. We can determine that DSS improves Reynolds' Number (RN), since RN is proportional to both speed and wing-chord-scale size. Suffice it to say Reynolds' Number is already significantly reduced or compromised from smaller scale wings in modeling. It should not be dangerously handicapped further by lower scale speeds compared to DSS. This perhaps acknowledges that we can scale the size of our model, but not the distance between the air molecules we fly through to sustain flight. Since our smaller models fly in comparatively "thin or expanded air", excessively slow speeds (such as scale speeds) can easily invite stalls. In straight flight, better stability and improved realistic lower angle of attack is also achieved with DSS to avoid stalls compared to those required using slower scale speeds. Modelers may build light-weight models to minimize stalling speeds from this environmental feature, but this will do nothing to achieve other maneuver realism features if attempted with scale speeds compared to DSS.

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