BladeVR-7b

SynchroLite ~ Rotor - Blade - VR-7b - Composite

Overview:

Reason for selecting VR-7b:

The primary reason is that this airfoil was designed for high lift, not fast forward flight (ref: Boeing Vertol). This is well suited to the ultralight FAR Part 103 limitations on maximum weight and maximum airspeed. It also is probably the reason that Ultrasport selected this airfoil.

The following consists of information related to the construction of composite rotor blades. Require 2 left hand and 2 right hand

For the CVJ+HS 3-blade rotor, consider leaving the rotor radius 8.67 feet even though the number of blades has increased by 50%. This is because the GW has increased from 550 lbs to 660 or 700 lbs. which is an increase of up to 27%. Then taper the blades to less than 5.25" at the tip and perhaps increase the root chord slightly, along with the increase in the roots thickness.

The taper might be from 5.75" at the root to 4.75" at the tip.

The blade should also be made stronger to handle the increase in-plane and out-of-plane loads from the CVJ+HS.

Additional Information on the VR-XX Blades:

	OTHER: Aerodynamic - Blade Profile - VR-9	1043
	OTHER: Aerodynamic - Blade Profile - VR-8 & VR-8b	1042
	OTHER: Aerodynamic - Blade Profile - VR-7 & VR-7b	0733

General Data:

Profile: - VR-7b, with a -2 degree trailing edge tab.

Span: - 8.667-ft. radius. 1.0-ft cutout. The actual blade will be 8'-0" or very slightly less.

Mounting: - On single pin ??? so that all 6 blades may be swung parallel to each other for ground transportation.

- Held in position by adjustable drag link. ???

- OR have two pins ???

Chord: - 5.25"

Twist: - -10º Linear.

Taper: - Don't rule out yet. First plot downwash over combined disk area. Perhaps 4.75" to 5.75", since the solidity is already high and the chord should not be less than 5", due to Reynolds number.

Material:

Spar: - Aramid fiber (Nomex) honeycomb core sandwiched between unidirectional carbon composite.

Skin: - Bi-directional carbon cloth. 20/70/-70/-20.

Leading edge weight: - Tungsten wire.

Tip:

Consider radius on leading corner.

Construction:

Maybe initially - Vortech 8-H-12 extruded aluminum with 4.75" chord or Vortech 0012 with 5.7" chord.

Group B:

	DESIGN:	B188	MAKE:	B248
		Information on Composites (A029)

Item:

Name:

Item:

DESIGN:

	Rotor - Blade - Composite - VR-7b - Planform LAYOUT		0673
	Rotor - Blade - Composite - VR-7b - Root		0236
	Rotor - Blade - Composite - VR-7b - Drag Brace Mount		0723
	Rotor - Blade - Composite - VR-7b - Drooped Tip (anhedral)		0740
	Rotor - Blade - Composite - VR-7b - Trailing Edge Block		0806
	Rotor - Blade - Composite - VR-7b - Centers, Radii & Moments		0826

MAKE:

	Rotor - Blade - Composite - VR-7b - Assembly	0672
	Rotor - Blade - Composite - VR-7b - Skin	0676
	Rotor - Blade - Composite - VR-7b - Skin - Cloth	0722
	Rotor - Blade - Composite - VR-7b - Spar	0675
	Rotor - Blade - Composite - VR-7b - Core	0674
	Rotor - Blade - Composite - VR-7b - Retainer X Will be replaced. See Root	0678
	Rotor - Blade - Composite - VR-7b - Tip	0679
	Rotor - Blade - Composite - VR-7b - Trailing Edge Block	0684

Special Tool:

DESIGN

	[Special Tool - Blade - Curing Forces]	0728
	[Special Tool - Blade - Core Cutter]	0668

MAKE

	[Special Tool - Blade - Female Mold]	0725
	[Special Tool - Blade - Pseudo Skin]	0726
	[Special Tool - Blade - Bladder]	0727

Last Revised: February 11, 2009