okikuma
Member
A good friend of mine sent me this video of Robinson R44 performing an emergency autorotation. Great outcome even though the Robbie was bent.
Several comments:
At the start of the video, the altimeter displays approximately 1,200 ft. MSL, the field elevation. The cell phone is mounted whereas the video viewer cannot see the cluster of warning lights at the top of the instrument panel, and blocks the top portion of the airspeed indicator. All the engine instruments are in the green. The main fuel tank is full and the auxiliary fuel tank is half full (think about the fuel load and the weight of three men and equipment - most likely very near gross weight).
Several comments:
At the start of the video, the altimeter displays approximately 1,200 ft. MSL, the field elevation. The cell phone is mounted whereas the video viewer cannot see the cluster of warning lights at the top of the instrument panel, and blocks the top portion of the airspeed indicator. All the engine instruments are in the green. The main fuel tank is full and the auxiliary fuel tank is half full (think about the fuel load and the weight of three men and equipment - most likely very near gross weight).
The pilot flies a normal takeoff profile and accelerates to 60 Kts and climbs up to and level's off at 1,300 ft MSL (100 ft AGL) and maintains 60 Kts. The next photo is right when the engine quits.
The pilot immediately dumps the collective, brings back the cyclic to set up for autorotation with the desire to land straight ahead. One can hear he's adjusting the collective to maintain optimum rotor RPM by the on and off buzzing from the Low Rotor RPM alarm.
During the decent, he notices a set of wires ahead and decided to turn 90 degrees to the left to avoid a wire strike. The turn bleeds off forward airspeed. The pilots notices this and made a mistake by lowering the nose. During autorotation, one does not want to lower the nose because that will "unload" the rotor and cause rotor RPM to decay. In the video we hear the Low Rotor RPM alarm now buzzing constantly because of this action.
The aircraft is too low to regain lost rotor RPM even though he's aggressively flaring trying to "load" the rotor. The aircraft is now within the avoid operational zone of the Height Velocity Curve.
During the flare, he hits the tail cone/tail rotor and it separates from the aircraft. The resulting high decent spreads the landing skids.
The last photo is back on the ground, the altimeter displays 1,200 ft MSL
Never-the-less, all in the aircraft were uninjured and it was a very successful emergency.
A good day!
I've never flown a 22 or 44 Robbie (too heavy). I'm impressed over the 500 ft/min rate of decent.
I'm used to much greater rates of decent in other helos I've flown within.
Wayne
The pilot immediately dumps the collective, brings back the cyclic to set up for autorotation with the desire to land straight ahead. One can hear he's adjusting the collective to maintain optimum rotor RPM by the on and off buzzing from the Low Rotor RPM alarm.
During the decent, he notices a set of wires ahead and decided to turn 90 degrees to the left to avoid a wire strike. The turn bleeds off forward airspeed. The pilots notices this and made a mistake by lowering the nose. During autorotation, one does not want to lower the nose because that will "unload" the rotor and cause rotor RPM to decay. In the video we hear the Low Rotor RPM alarm now buzzing constantly because of this action.
The aircraft is too low to regain lost rotor RPM even though he's aggressively flaring trying to "load" the rotor. The aircraft is now within the avoid operational zone of the Height Velocity Curve.
During the flare, he hits the tail cone/tail rotor and it separates from the aircraft. The resulting high decent spreads the landing skids.
The last photo is back on the ground, the altimeter displays 1,200 ft MSL
Never-the-less, all in the aircraft were uninjured and it was a very successful emergency.
A good day!
I've never flown a 22 or 44 Robbie (too heavy). I'm impressed over the 500 ft/min rate of decent.
I'm used to much greater rates of decent in other helos I've flown within.
Wayne