- Aug 8, 2009
Only from the outside. It's still a tube aluminum or carbon fiber for the basic frame. 2 leading edge tubes, 1 keel, and over the decades from 1 cross spar, to a 2 piece hinged floating cross spar.
The "control bar" and kingpost, are cable braced Structure that takes the lift & landing loads.
Competition gliders eliminate the kingpost & it's wires, with a heavier and more complex cross spar, internally. Northwing also makes strut braced trike wings and a glider, that eliminate upper rigging, and the main side cables, at the cost of weight.
The basic frame is indeed simple. A time traveller bringing the bare frame of a modern recreational glider would impress a 1979 glider maker with the high aspect ratio, and the hinged cross spar might inspire an early revolution in control/handling, but without the 3 dimensional sculpture that is the sail & battens, would not shock anyone.
Ironically, the complex sail alone would be a failure, if it was teleported to a 1979 glider builder, unless he saw the articulated frame too. It literally would be nigh impossible to turn.
In contrast, for a Kasper Wing, or Quicksilver, is very easy to grasp the ladder frame and cable bracing. The part count is higher, than a flex wing, but only for the hard metal or composite parts. It's still going to be one wing skin/sail. The complexity & curves of that sewn "part" are orders of magnitude different.
The platform of post # 2415 is intended to be a folding flex wing a bit more complex than the modern hang glider.
The comparison with the rigid ladder wing of the Kasperwing is valid as far as the simple and cheep goes except the Kasperwing does not pack into the “tube” of a hang glider for storage and transport.
The hang glider is no longer simple and cheep when the storage and transport of the flex wing is required and the wing morphs into the rigid wing of a Swift or an Atos. (Billy time for you to comment here).
VB - The goal is to apply the platform of post # 2415 to a flexwing folding frame that does not need the complex controls of the rigid flying wings whether it be a Blackstrom plank or a B-2 stealth bomber.