Electric Duct Fan (EDF) Self-Launch Glider?

On 1/17/2011 11:59 AM, CLewis95 wrote:
Assuming:
- L/D 40:1 850 pound Sailplane (in my case Genesis 2)
- Cluster of (3) currently available EDF Units producing combined ~60
pounds STATIC THRUST (AFTER taking into account loss of efficiency do
to close clustering of intake ducts)
- Battery capacity for ~10 minutes full power .. no reserve
- 2,500ft Paved Runway .. No Tailwind
- Sailplane pre-positioned on runway (not taxied to runway)
- Goal altitude of ~1,500ft AGL

I should have added: "Starting from 1,000ft MSL"
Curt -95

I like the idea, but starting the quest with a sustainer, because 60 lbf
would be unsafe on a 850 lb glider. 2500 runway? You'd still be on the
ground, as it'd take ~40 seconds to get to 60 mph. One fan would just
keep you up; two fans would let you climb. You could try a single fan
most easily by mounting it externally - no retraction. You'd probably
learn a lot with little investment.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)