B134
MAKE: SynchroLite ~
Control - Flight - Cyclic
Pitch Angles from Helicopters in Prouty's Book:
[Source ~ RWP1 p.683]Longitudinal
The avg. 'aft' value of the best 11 helicopters is +13.45º.
The avg. 'forward' value of the best 11 helicopters is -8.04º.
The average longitudinal cyclic range of all helicopters is 23.54º.
The greatest is 34º.
The Robinson R22 is -9.0 to +11.0 (20º)
For the SynchroLite use -9º +13º; total of 22º.
Lateral
The avg. 'left or right' value of the best 11 helicopters is +/- 7.43º.
The average lateral cyclic range of all helicopters is 15.07º.
The greatest is 20º.
The Robinson R22 is -9.5 to +6.0 (15.5º)
For the SynchroLite use +/- 8º; total of 16º.
Opposed (Differential) Lateral Cyclic:
For reasons see:
DESIGN: SynchroLite ~ Rotor - Disk - Opposed (Differential) Lateral CyclicIdeas for the Handling of Lateral Cyclic during Forward Flight with Intermeshing Rotors:
For problem see: Helicopter Aerodynamics booklet by Prouty, figure 5-3.
[Source ~ RWP2 p.24]For more see: Even More Helicopter Aerodynamics booklet by Prouty, figure 9-4 and .
[Source ~ RWP4 fig 9.4]Possible solutions;
Crazy Ideas for Lateral Cyclic with Synchropter:
1/ Have rotor hub located on inside of bank go lower at the time of applying lateral cyclic so that the teetering down blade on the outside rotor does not hit.
2/ Rock both rotors to the side in unison. This is like lateral weight shifting.
3/ Replace the teetering hinge with flexible blades, this way the downward bending comes outside the other hub.
4/ Give lateral cyclic to the rotor on the inside of the bank only, with maybe a little collective increase to the other. Note - greater lateral cyclic can be given to the inside rotor by having the lateral cyclic arms on the central control rocker made horizontal instead of perpendicular to the respective masts.
5/ Have the cone on the hub greater then the natural cone that will exist in flight. This way the blade will curve over the other hub.
Cyclic Stick:
Height:
The height of my crotch above the floor is 35". The height for an average male will be 32". The stick is going to be 21" from pivot to top of grip. This is 35.5" off the ground. The pilot will have to push the stick forward and step over the tube, between the stick and the seat to seat himself.
Horizontal Location:
The sports plane construction book says 18" - 20" ahead of seat back/bottom.
SynchroLite is located 20" from seat back/bottom. Shorter person can use thicker seat back cushion.
Miscellaneous:
Because the helicopter is very light weight shifting by the pilot might assist slightly with extreme cyclic control requirements,
but don't count on it.
From coding in FORM: [Controls - Flight]
Public Function cyclic_long_movement(Movement As Single) As Single
'To transfer longitudinal inputs from the pilot's cyclic stick to the swashplate.
On Error GoTo cyclic_long_movement_Err
'Cyclic data
'?? Me.[Longitudinal Fwd Max] = ?? 'Maximum longitudinal forward travel, at top of stick, in inches.
'?? Me.[Longitudinal Rear Max] = ?? 'Maximum longitudinal rearward travel, at top of stick, in inches.
'Cyclic Longitudinal data
' = -9 '[deg.] 'Maximum stick travel. Value must be doubled for 2-way total.
' = 13 '[deg.] 'Maximum stick travel. Value must be doubled for 2-way total.
' = 2.4999 '["] 'Length of front tube arm.
' = 1.6243 '["] 'Length of rear tube lower arm on bellcrank.
' = 3.0108 '["] 'Length of rear tube up arm on bellcrank.
Movement = Movement * (2.4999 / CyclicStick) 'Stick to rod connection point at front of tube.
Movement = Movement * (1.6243 / 3.0108) 'Bellcrank arms.
cyclic_long_movement = Movement 'Movement in inches at mixer box.
cyclic_long_movement_Exit:
Exit Function
cyclic_long_movement_Err:
MsgBox Err.Description
Resume cyclic_long_movement_Exit
End Function
Public Function cyclic_lat_movement(Movement As Single) As Single
'To transfer lateral inputs from the pilot's cyclic stick to the swashplate.
On Error GoTo cyclic_lat_movement_Err
'Cyclic data
'?? Me.[Lateral Max] = ?? 'Maximum lateral travel, at top of stick, in inches.
'Cyclic Lateral data
' = 8 '[deg.] 'Maximum stick travel?????.
' = 1.375 '["] 'Length of arms on rear end of cyclic tube.
Movement = Movement * (1.375 / CyclicStick) 'Stick to rod connection point at rear of tube.
cyclic_lat_movement = Movement 'Movement in inches at mixer box.
cyclic_lat_movement_Exit:
Exit Function
cyclic_lat_movement_Err:
MsgBox Err.Description
Resume cyclic_lat_movement_Exit
End Function
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Last Revised: September 4, 2003