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Biggles1049
19th Sep 2008, 18:25
Noted at Tibenham oh Thursday 18th September was the unique and
interesting Edgley EA-9 Optimist Glider BGA4093 / HPJ.
It is constructed using a material called FIBRELAM which is a board
material with fibre skins with honeycombe infil. Although other kits
were constructed this is the only example to have been completed..

Apparently it is at Tibenham for an experiment this weekend by some
University to attach 16 Electric motors and propellors to the wing
leading edges

A couple of images were taken of it on the runway prior to an aerotow
in normal configuration. It stands out from the crowd as it is bright
green overall with yellow trim

Side view Edgley EA-9 Optimist, BGA 4093, Private (http://www.abpic.co.uk/photo/1131199/)
Cockpit panel Edgley EA-9 Optimist, BGA 4093, Private (http://www.abpic.co.uk/photo/1131200/)

Hope this is of interest

Keith

Krystal n chips
20th Sep 2008, 04:22
Hmmm .....have to say it bears more than a passing resemblance to a Ka18 at first glance....apart from the tail skid.

Jamesel
20th Sep 2008, 06:58
According to articles by Derek Piggott, Bob Rodwell and others in "Sailplane and Gliding" & "Pilot", Edgley volunteers that he used the Ka-18 as the basis for the design of the EA9, as he wanted to prove the structural properties of the Fibrelam material, and not have to design and debug the aerodynamics of an entirely new glider. However, the wings were slightly clipped to 15.7 metres (from 16m) and the wing profile was was slightly changed/updated from a modified NACA 633 (with Wortmann leading edge modification) to a full Wortmann profile FX61-184 at the root and FX60-126 at the tip. Apparently some of the fittings on the prototype were actually salvaged from a Ka-18 hulk, so the resemblance is not just on the surface.

Wonder what the cost of the kits would be nowadays......

Icare9
20th Sep 2008, 09:02
to attach 16 Electric motors and propellors to the wing
leading edges

Won't that make it a Guinness entry with 16 engines??? Has anything had more?? How will 8 a side fit without the outer propellors fouling the ground??

norwich
20th Sep 2008, 11:57
Icare9, I think that record should have gone to the proposed HS 141, which had 8 lift engines each side and 1 propulsion engine under each wing ! So any offers above 18 ! Keith.

http://i261.photobucket.com/albums/ii58/keithnewsome/hs_141b.jpg

wz662
20th Sep 2008, 19:21
16 electric motors!

Range = available length of cable :p:p

Genghis the Engineer
21st Sep 2008, 12:24
Graham Dorrington at QMW has been playing with his proposed electric powered EA9 for years, before that he was developing a manpowered airship at Southampton University. A man with, err, interesting, ideas - I've known him for years, but can't honestly say I've ever been very convinced by any of them.

G

Biggles1049
22nd Sep 2008, 20:53
Well it flew on at least 3 times last weekend with the eight battery packs and 16 motors and propellors attached - see image below. Experiment was to identify if sustained flight could be maintained using the props
http://i324.photobucket.com/albums/k355/Biggles1049/optimistlaunch.jpg

henry crun
22nd Sep 2008, 23:15
It is obviously being towed aloft in that photo, do you have any information on whether or not it was able to maintain level flight on battery power after release ?

tinpis
23rd Sep 2008, 00:58
Its a little on the large size for your park Henry :rolleyes:

astir 8
23rd Sep 2008, 07:27
Looks like they're preparing for a rocket attack on someone!

Are the motors pushing as well as pulling then? I can only see 8

The Edgeley was a nice try but I supposed wouldn't have been able to compete cost & performance wise with secondhand glass gliders.

Biggles1049
23rd Sep 2008, 18:21
There are eight power cells powering eight forward facing and 8 rear facing motors and props - more closeup shots showing this

http://i324.photobucket.com/albums/k355/Biggles1049/DSC06614.jpg

http://i324.photobucket.com/albums/k355/Biggles1049/DSC06613.jpg

http://i324.photobucket.com/albums/k355/Biggles1049/DSC06624.jpg

wonderboysteve
24th Sep 2008, 13:50
Icare9, I think that record should have gone to the proposed HS 141, which had 8 lift engines each side and 1 propulsion engine under each wing ! So any offers above 18 ! Keith.

IIRC, TSR2 would have been given VTOL capability by being launched from a platform powered by about 70 engines. OEI performance wasn`t bad though...