Originally Posted by
kulkarni
So are there any known helicopters in service currently which can exhibit a loop? what would be the height loss after the loop is midway (I would say nose pointing down) till the helicopter stabilises in straight and level flight?
Plenty of types are physically capable but will be operating totally outside of all design criteria and fatigue limits.
Nose pointing down is 3/4 of a loop - 1/2 a loop is upside down at the top. Height loss is not so great because a helicopter does not need airspeed to generate pitch authority (like a FW). The control authority of the head can pitch the fuselage up. I’ve never done a RW loop but have rolled inverted and pulled through (from below 40 kts) and bunted 90 degrees nose down, rolled 180 and pulled out. In a 5 bladed Eurocopter product.