Nick sez:
No helicopter that I know except Comanche can easily withstand this enormous pedal input and retain control or rotor structural integrity, and no helicopter is required to perform that maneuver. Teetering rotors will flap wildly, and will perhaps mast bump, with disasterous results
Question: why will the teetering rotor flap "wildly" in a sideslip?
As far as I know, the rotor doesn't care what direction its flying in. In forward flight in a R22 at close to 100 kts, the flapping is only a few degrees. There is still plenty of stick travel left with which to control the aircraft. In a full on sideslip, the airspeed won't be anywhere near as great, and the flapping will be all that much less. The only difference is that it will be lateral flapping.
The FAA says:
Sideslip creates lateral flapping in excess of that encountered during normal flight. This excess flapping allows less margin for lateral cyclic maneuvering in response to a low g induced roll.
This does not sound like wild flapping to me. The simple realization that some lateral flapping of a couple of degrees will occur in a sideslip has been overblown to where any amount of out of trim is red flagged as a big no-no that is going to slice your tail boom off.
I don't think so.
The FAA aslo says
http://www.faa.gov/certification/air.../ASW-95-01.htm
Mast bumping may occur with a teetering rotor system when excessive main rotor flapping results from low g (load factor below 1.0) or abrupt control input.
Trouble is, low g does not increase flapping as far as I know. A teetering rotor requires a load in order to produce lift. The lift and load (weight) are a force pair. Neither one exists without the other. Remove the load(zero g) and the lift is zero. Thus there is no control since the rotor can only pull on the airframe, (it cannot produce torque thru a teeter joint.)
I would expect minimal flapping when the lift is minimal on advancing and retreating sides of the rotor.
Flapping is only a problem if the rotor speed decays (which it well might in a pushover)and then the load is reapplied. Flapping will increase as the rpm decreases.
The real issue in low g is that the tail rotor thrust will roll an R22 and application of cyclic will not stop the roll due to the loss of rotor thrust. The rotor will tilt in response to cyclic because it is still flying, but tilting the rotor is not enough, you need thrust.