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Last Modified April 6th 1999
March 1st - 9th Still recuperating.
March 10th Got my pilot medical certificate reinstated :-) Did some more work on the aileron trim tab design.
March 11th Flew again :-)). I am just about finished with the design of the landing light though I do wish I had access to a wind tunnel just to prove that I can retract the light at speed.
March 12th No building, study time.
March 13th -14th No building. Attending a test pilot's training course. I passed the exam so can now apply to the CAA to test any Experimental aircraft that I have a type rating for.
March 15th I
lied. While I was laid up I spent quite a bit of time working on
an aileron trim system as you can see from the aileron at the
left. Don't worry, it's a spare one and will never get put onto
the aircraft!
I tried a couple of designs embedding the trim tab within the aileron itself and with the second try actually got as far as having a trim tab operational.
I abandoned that method while studying for my test pilot exams and decided that there was a possibility of flutter at high speed using that technique if the tab wasn't dynamically balanced - not easy for a light tab.
I proceeded with a duplicate of the design that MAC prepared for the Lancair which is a simple design using a piece of hinge as the tab and driving this with the servo. I am much happier with this design as it effectively duplicates a fixed trim tab and requires no dynamic balancing of the tab itself. The important factors to consider with this design are the rigidity of the control and the quality of the construction.
I have proven to my satisfaction that the design concept is sound and can be easily installed and maintained.
The pictures above show the proof of concept unit. A section of foam is cut out from the lower surface through to the upper surface. A reinforcing layer of bid will be added to the top surface lapping onto the sides of the hole. A reinforcing plate duplicating the method used on the aileron bellcrank examination holes will be used to support the plate over the lower surface - the plate itself being reinforced with bid. The hinge needs to be inset into the surface on the aileron and the slot for this will be supported with flox. A small section of bid will support the trailing edge where the hinge attaches. I haven't yet decided on the final size of the tab itself but I am thinking of making it 5" long. The angle aluminium used to drive the tab will be hard riveted to the tab. I need to work on the shape of the vertical piece of the angle to permit maximum drive without fouling the drive arm and to make it little more "aerodynamic".
March 17th Worked in Wellington, came home and diagrammed the aileron trim system. ftp://ftp.kaon.co.nz/pub/ailtrim.jpg. I am still doing some research on how wide the tab should be and the shape and attachment point of the drive arm attached to the hinge needs to be played with.
March 18th -19th Spent some time sanding the stabilators and clecoed the top back onto the aircraft.
March 20th Dragged the fuselage outside and rigged the wings to check to mark off the wing shape and check the positioning of the lift pins against the fuselage. Both pins are centred on the metal plates so I will go ahead and so the reinforcing lay-ups for the fitting of the lift pin sockets.
March 21st No building
March 22nd Removed the fuel selector so that I can add a long shaft to it. This shaft will allow the selector to be placed on top of the tunnel where it can be easily reached by the pilot. Tim Ward came up with the idea of using a Speedbor 2000 drill extension shaft for this task.
March 23rd - 28th No building. A busy week - going away party for my brother, school Japan trip parent's meeting, SAANZ monthly meeting, National Rowing Championships with Stefan, planning meeting for the SportAvex 2000 Airshow. In that order. I wanna holiday!!
March 29th Did the eight wing lift pin reinforcing lay-ups - two each side inside and out. I used a four layer bid lay-up 15cm wide cut one complete width of the cloth for this and was able to do all of the lay-ups with the one piece. Do not cut the ends of the cloth square as the triangular ends very nicely lap on to the thigh support for the two inside forward lay-ups. I peel plyed the entire surface of the outside lay-ups and the edges only of the inside lay-ups. Now all I have to hope for is that the weather is fine over Easter so that I can get the wing incidence set.
March 30th - 31st Removed the flaps from the wings to make it easier to do the incidence setup.
