The kind staff at Geneseo allowed us to keep WW1 in their hangars over the winter of 07-08. The airplane was recovered in 08 and brought back to our home field in Brampton, Ontario.
The craft was stripped into major components and the damaged airframe sent to one of our members who effected the main structural repairs to the fuselage. This involved nearly everything forward of the firewall including the starboard side cabanes.
Work was put aside for the summer airshow season and only really started up in October of this year. Since I am building my own D7, I was asked to co-ordinate the repairs and modifications to WW1. My new status as 'retired' probably influenced this decision as well.
The first task for me was to compile a schedule of repairs. This indicates what has to be done, who will perform the work, who will check the work and an estimate of hours to complete. We quickly came up with about 700 hours of work to be done. Not everything is strictly repairing but incorporates updates and modifications to the original aircraft.
We have defined some primary guiding principals for this project. Safety first; Improve the pilot experience; Make it closer to the plans; Improve the flight characteristics.
A survey of the complete stripped down airplane shows that there were many deviations from the original plans. The reasoning for many of these changes has been lost over 3 decades and there are challenges inherent in changing something that has come to be accepted as the norm. Many things will not be changed because we would rapidly approach the stage of building a completely new aircraft. Balance is the key in this project using the original Rousseau drawings as the benchmark/touchstone. It may not be 'perfect' D7 building but the aircraft has flown successfully for 30 years and I won't argue with success.
Some examples:
The upper wing.
The wing is a massive structure almost 30 feet long with a chord of about 5 feet. Early reports (McCook Field) indicate that the wing should weight in at 150 lbs. Our wing weighs 194lbs with ailerons. The ailerons are overweight at 10 lbs each leaving a wing of 174 lbs with hardware.
Two reasons for this are the solid sheeting of the leading edge, as opposed to the 'saw tooth' pattern of the original and a scalloped trailing edge of wood instead of a simple 1mm wire.
To replace a 1mm wire and the rear lateral rib stiffener, this wing has a trailing edge made of a continuous wedge of spruce skinned top and bottom with plywood. While none of these components weigh much on their own, together we end up with 24 extra pounds. There is little that we can do without building a new wing so the top wing will remain as it is. The ailerons which have been built with heavier tubing than necessary are a running improvement that we can make in the future.
Second example, the seat.
The original seat is shown below on the left. It is made from 3/4" and 1/2" plywood. The substitution of a fokker design seat made from 1mm aluminium saves 6lbs. It is also 4" narrower than the wood seat! 6 pilots familiar with flying this aircraft have all commented on the comfort and fit of the new seat.
Seat frame. Note location of vertical seat brace brackets. These would normally be at the corner juncture of the seat frame. I decided that this was a case of modify, not replace.
Thre are many other similar examples within this aircraft and one of our teams objectives is to replace unnecessary 're-engineering' with oringial design components. If we can shave a few pounds here and there, we will end up with a lighter aircraft and follow our primary guiding principals defined above.
TBC....
John