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View Full Version : Winter project = repair + modify Lennon plane


pierre sarault
2013-02-25, 11:23 PM
On 2012-10-24 I reported that I was attempting to complete the repairs and modifications to the ill-fated Andy Lennon-design "Snowy Owl" (I also refer to it as White Owl and the designer at times referred to it as "Harrier" on some of the original drawings - thanks Brian). I had already pieced together the wing and by exploring (exploratory opening) I discovered that the binding of a flap was due to a return spring added to the bellcrank on only one of the two flaps...still a mystery as to why this was done...maybe prevent flutter (?).
Now all I have to do to the wing is design and build a new dual servo tray in the midsection that will also serve as reinforcement to the spars.

The fuselage was badly mangled just ahead of the CG (behind the wing LE) and had to be amputated...and redesigned with a bit more strength and space for the equipment.
I decided to turn it into a radial-engined taildragger by reusing the same LG and several "surplus" components like the engine, electronics, new fuel tank...etc. etc.. The new forward fuselage of lite-ply is sandwiched on top of the existing fuselage center section and forms the structure to support a new radial cowl support / firewall with shims to position the OS 40 SF with 2 deg. right and 1 deg. down (thrust angles). The dimensions, moments and design CG have been adhered-to according to the original design by Andy Lennon.
The new forward fuselage also has a reinforced "floor" to support the repositioned LG (from trike to taildragger). I plan to make the cockpit like that of a DH Beaver just aft of the radial cowl...this is starting to sound real interesting = a T tail taildragger with a radial cowl and NACA droop wings with HUGE flaps!

pierre sarault
2013-03-07, 06:23 PM
Part 2: The rebuild is progressing; here are pics of test fitting the T tail and Wing. The LG was installed (the final wheels will be 2.75 in.) and so was the tailwheel (with some mods). The LG needs toe-in adjustment and the engine mount needs longer 4-40 cap bolts.

Next is the fuel tank mount, the servo mounts for throttle and rudder, the new DuBro fuel filler bracket, the fuel lines, throttle pushrod.

After that the wing: aileron and flap servo trays, new linkages, remove the spring return on one of the flaps and install wing bolt-down supports in fuselage and wing,,,then the center section LE and TE fairings.

And then I'll tackle the cockpit and canopy (fastened by nylon L brackets to the fuselage)...if I have time maybe I'll use some old instrument bezels and face-plates (?); framing will either be brass or ABS/polystyrene square tubing.

I find this type of challenge interesting (and sometimes rewarding) and appreciate your comments and suggestions.