Dragonfly ~ 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 3 left hand and 3 right hand

General Data:

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

Span: - 8.0-ft. radius. 24" cutout.

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

Lead/lag: - Moves in conjunction with other blades, due to tie-bars.

Chord: - 4.75" @ 0.75R

Twist: - Linear at 1.0-degree per foot.

Taper: - Don't rule out yet. First plot downwash over combined disk area.

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. Consider anhedral at tip, if it will reduce tip loss and tip vortex.

 

Construction:

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

Have a 'passageway' down the center of the blade from root toe tip for control and/or safety devices.

There is mention of the VR-7 profile for the Dragonfly in Access ROTOR Module. Look at what it is all about.

Note: The following web pages, which are in red are SynchroLite pages. Comparable Dragonfly pages will be produced later.

Note that the mass of the Dragonfly blade will be about 61% (or greater) of the SynchroLite blade. This is due to a smaller radius, smaller chord and greater cutout.

Group B:

 

DESIGN:

B188

MAKE:

B404 B248

 

 

Information on Composites (A029)

 

 

Item:

 

Name:

Item:

SynchroLite 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

1209

0672

 

Rotor - Blade - Composite - VR-7b - Skin

1285

0676

 

Rotor - Blade - Composite - VR-7b - Skin - Cloth

1286

0722

 

Rotor - Blade - Composite - VR-7b - Spar

1287

0675

 

Rotor - Blade - Composite - VR-7b - Core

1288

0674

 

Rotor - Blade - Composite - VR-7b - Retainer X Will be replaced. See Root

 

0678

 

Rotor - Blade - Composite - VR-7b - Tip

1299

0679

 

Rotor - Blade - Composite - VR-7b - Trailing Edge Block

1290

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

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Last Revised: December 5, 2003