Rangoon

Today I talked with another pilot who helped me understand the real difference between traditional helicopters and fixed-wing aircraft when it comes to coordinating turns. As stated above, it's not unusual for me to bank the helicopter right but input left pedal to counter the greater torque as I pull collective pitch/increase power. Or, during a descending left turn, I'll input right pedal in response to decreased pitch/power. As he explained it, fixed-wing aircraft use rudder to coordinate a turn due to adverse yaw from the aileron - more lift/drag on one side causes that wing to fall behind the other wing, which has its left/drag reduced. The rudder makes up for adverse yaw. Helicopters don't suffer from adverse yaw (although we suffer from plenty of other aerodynamic phenomena instead). Can the fixed-wing pilots here confirm I've got that story straight?

My understanding is that it is like a friction lock which holds the collective lever in place. At least in the sim of course it also resets the ALT HOLD marker. I think idea is that the brake keeps the pilot from inadvertently bumping the collective while eating his sandwich and whatnot.

One small tidbit which I don't think was mentioned regarding the power limit is that this is the most power (given the throttle constraints) that the engine can produce. The governors manage engine power, and therefore rotor RPM, based on the collective pitch setting: more pitch, more drag, more power required. So if you hit the power limit, while you can continue to pull more collective pitch, the engines will no longer answer with more power. You pull more pitch, more drag, *no more power*, so rotor RPM will droop.

Thanks for reiterating this. It's a very important distinction. In my profession, it's either coordinated or intentionally uncoordinated (as you indicated). You're absolutely right that coordinated turns are more efficient and professional, but they also just feel better to the client on board (some non-aviators do get nervous on board and that's only aggravated by sloppy flying). But frequently with photography/videography uncoordinated flight is essential to keep the frame regardless of the ground track. Oh, and in virtual combat! :) (thank you DCS) :thumbup: I'll have to pay more attention next flight for a better reply, but you're right that it's either 100% lateral or slightly forward. My instructor always insisted lateral, but that's because I kept pulling back on the cyclic in a subconscious effort to hold altitude (I think) rather than using collective. So it seems the 'right' answer must be simply lateral cyclic, no fore/aft pitch. And it probably is right. Now I just always feel a slight forward pressure during turns. It's probably me feeling the resistance of my early misconceptions, fighting the urge to pull back. Pitch = airspeed. Collective/Power = altitude. It really does work.

I'm not sure beyond the light helicopters I've flown, but if I bank the aircraft and just freeze my feet in place, trim is maintained throughout the turn as long as I'm in forward flight above (now I'm guessing - but will check during my next flight) about 40 knots or maybe less. As soon as collective (and therefore power) is changed trim is lost without input from the feet. It is common in right turns to use left pedal, in fact, because if I hold altitude I will need more power and therefore left pedal. Right turn,- left pedal to hold trim. I guess whether it makes sense or not, that's been my experience. And I resisted that in my early days because I had been flying sims since the early 80s - it was habitual to engage my feet during turns (a la fixed-wing flight models and the little real-world fixed-wing flying I had done at that time) but my instructor kept scolding me. Eventually I stopped moving my feet and my turns improved dramatically. Unless I was changing power (but generally it's still less pedal movement than a comparable turn in an airplane unless the power change is drastic). I'm glad DCS prompts discussions like this. And it makes me want to fly a lot more helicopter types. Edit: grammar

Thanks for the replies sobek and EinsteinEP. I should clarify - to maintain a true level turn, one does need to add power since some of the vertical lift becomes horizontal. To maintain constant altitude power has to be added (because collective pitch must be raised), and therefore left pedal (with a counterclockwise main rotor). But aside from that, tail rotor is not used for coordination. There is significant weathervaning, yes, due to the shape of the helicopter (tailboom, etc.) and the vertical/horizontal stabilizers - esp. in cruise. But in a turn, you tilt the rotor disc and the fuselage basically swings out 'behind' the disc (like a pendulum) and that is what turns the helicopter. No rudder/tail rotor pitch change required if power doesn't change. I've only flown three types of helicopters, but this is the case in my experience. What you're saying makes sense if use of rudder in DCS is partly due to the autopilot's heading hold fighting the pilot's inputs (I know that's a topic floating around here a lot). Whether it's right/wrong/fixable it at least makes sense what's happening. And if it's wrong - glad to hear it'll likely be fixed. And yes - I'm quite sure the maneuverability of the Black Shark is top notch and designed to do much more than I'm used to. Sure I can jam the pedal in cruise flight and find myself with some high crab angles, but I wouldn't feel confident in things holding together for very long at high airspeeds! :) That said, even the little civilian helicopters are extremetly maneuverable compared to fixed-wing aircraft and can fly sideways at 30-40 knots all day long. I think I'm still on topic - curious to see how the flight model evolves with the patch. They've brought the Black Shark to life with such fidelity that my inclination (for the first time ever in a PC helicopter sim) is to defer to the simulation, not my own experience. So any oddities I assume are true to the Ka-50 and mark down as differences before I dismiss them as inaccuracies.

Regarding EinsteinEP's and Sharkster64's posts: Talking about use of rudder in turns while flying the black shark, this brings up a nagging question which has been brewing in my mind while learning to fly this coaxial system. I fly helicopters for a living, but have never been in one with a coaxial system (until now!). Normally in helicopters, you don't use tail rotor authority to coordinate a level turn like airplanes do. The tail rotor's main job is anti-torque, so if I turn and descend or turn and climb I'll use tail rotor inputs to coordinate as a reaction of the change in power. However in the black shark I do seem to need rudder to coordinate level turns. Anyone know why this is? Maybe it's also related to speed (I'm normally cruising at 100-120 knots, which is about 190-225 kph).