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rbf3999
October 10th, 2008, 02:54
Hey fellaz and fellettez. A buddy of mine and I like to fly around landmarks of the world and just check out the scenery. I like a good fast helicopter for that, but I like the great visibility of a wide open cockpit with small panel like the small choppers. So...my solution is to take the Cicare CH-7 Angel chopper and modify it so it's real fast :)

My question is, how do I stop the chopper from shaking at over 100kts? What determines at what speeds it will shake? I'd like to turn that off :)

Thanks for any help.

wombat666
October 10th, 2008, 05:13
Hey fellaz and fellettez. A buddy of mine and I like to fly around landmarks of the world and just check out the scenery. I like a good fast helicopter for that, but I like the great visibility of a wide open cockpit with small panel like the small choppers. So...my solution is to take the Cicare CH-7 Angel chopper and modify it so it's real fast :)
My question is, how do I stop the chopper from shaking at over 100kts? What determines at what speeds it will shake? I'd like to turn that off :)
Thanks for any help.

Fly slower.
:d:d:d:d
Sorry, but I just could not resist that one, me bad.
My chopper of choice is the HC Bell412 PE, and I've never experienced the 'shaking' you mention.
Perhaps you might receive some assistance from the Hover Control forums.

Desert Rat
October 10th, 2008, 10:41
If you like a glasshouse with a decent turn of speed, try a Hughes 500, Mb105 or a Gazelle? Not a Bell 47 dome, but not to bad for viz.

Jamie

JO_Wingnut
October 10th, 2008, 10:48
That shaking is happening because you are overspeeding the aircraft. It happens in real helicopters too. The rotors are designed to fly through the air like wings, and because they are advancing and retreating, The faster you go, the faster the advancing side of the rotors are and thus have more lift and the retreating side loose some lift. The advancing side is comes close to exceeding the sound barrier. Because of the lift being greater on the advancing side and loss of that lift on the retreating side we have the rock or bounce. Simply slow down and you won't have the problem. Most helo pilots fly at approx 80% throttle and when it is pushed, the rotors can take damage and the engines burn up.

Tanmann
October 10th, 2008, 15:23
While it's true lift is not equal in forward flight as far as the retreating and advancing rotor blades are concerned, this is compensated for by allowing the rotor blades to to flap as they rotate. The advancing blade flaps up and the retreating blade down. This equalizes the lift. It also makes for smoother rotation of the rotor dynamic system. The problem arises when you exceed a certain airspeed and the retreating blade can no longer flap downward causing retreating blade stall. This can cause severe shaking and loss of controll if not caught early. Most of the shaking in the R/C choppers I fly is caused by out of balance rotating parts. The faster you fly the more inertia these parts have and the vibrations increase. As I understand it, most choppers will run into retreating blade stall long before the advancing rotor-tip goes transonic. I think the shaking in the sim is a try at realism. The faster helicopters fly, the more they shake. Maybe they over did it a bit. Charles

aeromed202
October 11th, 2008, 06:14
I believe you can change the speed at which that shaking starts by editing the aircraft cfg MOI. An example below is from a Bell UH-1H.
As you fly faster take note of how the view shakes, either left to right or up and down then increase the value in either the yaw or pitch. I usually try increments of 500 to 1000 or more depending on the starting value. This will cause the shake to start at a higher speed. You can adjust for realism or ease of flying, however cfg edits usually affect other flight characteristics so save a back-up first. You will find the aircraft responds more sluggishly with increasing inertia so other edits may be necessary.

Moments of Inertia
empty_weight_pitch_MOI=6000.000
empty_weight_roll_MOI=4000.000
empty_weight_yaw_MOI=10000.000
empty_weight_coupled_MOI=0.000
CG_forward_limit=0.000
CG_aft_limit=1.000