Risk factors. Factors that increase the risk of stuttering include: 1  Having relatives who stutter. 2  Stuttering tends to run in families. 3  Delayed childhood development. 4  Children who have developmental delays or other speech problems may be more likely to stutter. 5  Being male. 6  Males are much more likely to stutter than females are. 7  Stress.
The average speed for a four-seat helicopter is 130 to 145 miles per hour. Because smaller helicopters have smaller engines, the average speed for a two-seat is 90 to 105 mph. The fastest helicopter on Earth as of 2014, the X3 Eurocopter, can fly at 300 mph. Keep Learning.
Depends on type. Of the ones I've flown (cruise speed): S300CBI - 70 kts. R22/44 - around 100. EC135 - 120 kts. EC225 - 145 kts. So not that fast... The current speed record held by the Lynx is 173 kts. But once you start flying that fast in a helicopter things start to shake quite a bit and you dont feel very comfortable, like going 100 mph in an old car! :)