Wednesday, February 28, 2007

Honestly I have not been working on the 701 much recently. We had some visitors on Sunday and I used the top rear wing skin to verify that the distance between the spar and rear channel is correct.

So what is the reason I've been so busy?

Wednesday, February 21, 2007


EAA 1440 had another meeting last night, with a great analysis of accident rates and causes for homebuilts, along with comparisons to the production fleet.

I've had this idea of formalizing risk mitigations knocking around in my head for a while. At Microsoft an employee determines a set of commitments and accountabilities for those commitments, which determine the results of the annual performance review.

This model seems like a good fit for something like the homebuilding process. Considering that the fleet accident rate for all Zeniths is about 2.14% ( higher than Lancairs, less than Seareys ), then I need to do something to minimize my individual exposure to risks.

At the moment I have no idea what the largest contributor is to the Zenith fleet accident, my commitments will be based on my perceived cause of accidents and the root causes of the overall homebuilt fleet.

Commitment: Flight training
Execution:
  • Meet with our EAA flight advisor. Meet with an EAA flight advisor who has specific experience with the CH701.
  • Obtain an additional 20 hours of float training. Attempt to find a reasonable source of amphibious training.
  • Attempt to find a source of CH701 specific training.
Commitment: Technical and safety review
Execution:
  • Hold a project open house before transport for final assembly
  • Meet with an EAA technical advisor, with a review of all airframe, fuel line, and FWF assemblies.
  • Have a trusted A&P do a review of the airframe assembly
  • Perform a full inspection at the following intervals of flight time:
    • 1, 5, 10, 20, 40, 60, 100
  • Have a trusted A&P do the annual condition inspection with me so I can learn how to maintain the aircraft.
Commitment: Fuel line & FWF safety
Execution:
  • Obtain help with the FWF installation by an experienced Rotax installer
Commitment: Further Mitigation
Execution:
  • Determine more commitments that are relevant for a safe completion of the project.

Sunday, February 18, 2007

We spent about two hours on Sunday. Part of that time was spent getting the inboard wing channel into place, and the rest on the flaperon brackets.

I believe that my rear wing channels may be a few mm aft, as I am having a problem with 7V4-6.

When I attempt to place the bracket, the after edge is more rearward than the rib. If I move the bracket forward then it gets between the rib and the channel.

Is the correction to attempt to move the channel forward, or to shim between the rib and the channel?

Project Status:
Wings: 36.5h ( 1h, 1h, 0.5h, 2.5h, 4h, 1h, 1.5h, 1h, 1.5, 4.5, 1h, 1h, 2h, 4h, 1h, 3h, 1h, 2h, .5h, 1.5h, 2h )
Flaperons: ( DONE! ) 23.5 hours spent ( 3h, 1h, 1h, 1h, 1.5h, 3h, 6h, 3h, 4h, 1h )
Paint Design: 2 hours spent ( 1h, 1h )
Elevator DONE!: ~31.5 hours spent ( 3h, 1.5h, 3h, .5h, 3.5h, 2h, 4h, 1.5h, 2h, 4.5h, 1h, 6h )
Horizontal Stabilizer DONE!: ~28 hours spent, 3 pieces replaced ( 3h, 2h, 2h, 2h, .5h, 1.5h, 3.5h, 1.5h, 5, 4.5, 2h, .5h )
Rudder DONE!, minus horn : ~16 hours spent, ( ~8h, ~8h )
-----------------------
Total Done: ~139 hours
Saturday night we were able to sneak in about an hour and a half of work. Tasks completed included cutting the outboard rear wing channel for the wing tips, discovering that the inboard heavy duty rear wing channel required trimming, trimming them, figuring out the measurements and hole placements for the 7V4-3 ( doubler ) and then pre-drilling it.

Luckily all the trimming produced enough scrap to fill in for some 7V6-3. I found Zenith really does not provide enough of that piece. I can't imagine that it cost's that much, or would be too difficult to produce.

Project Status:
Wings: 34.5h ( 1h, 1h, 0.5h, 2.5h, 4h, 1h, 1.5h, 1h, 1.5, 4.5, 1h, 1h, 2h, 4h, 1h, 3h, 1h, 2h, .5h, 1.5h )
Flaperons: ( DONE! ) 23.5 hours spent ( 3h, 1h, 1h, 1h, 1.5h, 3h, 6h, 3h, 4h, 1h )
Paint Design: 2 hours spent ( 1h, 1h )
Elevator DONE!: ~31.5 hours spent ( 3h, 1.5h, 3h, .5h, 3.5h, 2h, 4h, 1.5h, 2h, 4.5h, 1h, 6h )
Horizontal Stabilizer DONE!: ~28 hours spent, 3 pieces replaced ( 3h, 2h, 2h, 2h, .5h, 1.5h, 3.5h, 1.5h, 5, 4.5, 2h, .5h )
Rudder DONE!, minus horn : ~16 hours spent, ( ~8h, ~8h )
-----------------------
Total Done: ~137 hours

Wednesday, February 14, 2007

Building will be slow for the next several weeks...

Superbowl Sunday was productive and most of the rear wing channel for the left wing was finished. The remaining center piece was done on Monday.

Working on the rear channels alone is a challenge, an assistant is a necessity.

After much discussion on the Zenith list, I bought and tried a Drill Doctor XP2. What a piece of crap. I tried two #30 bits that we past their life and it made . A #40 was also tried and destroyed. If I hadn't received a refund from Home Depot you can bet that angry mails would be sent, but I really don't have the time. All three bits were made blunt, not matter what I attempted.

Project Status:
Wings: 33.0h ( 1h, 1h, 0.5h, 2.5h, 4h, 1h, 1.5h, 1h, 1.5, 4.5, 1h, 1h, 2h, 4h, 1h, 3h, 1h, 2h, .5h )
Flaperons: ( DONE! ) 23.5 hours spent ( 3h, 1h, 1h, 1h, 1.5h, 3h, 6h, 3h, 4h, 1h )
Paint Design: 2 hours spent ( 1h, 1h )
Elevator DONE!: ~31.5 hours spent ( 3h, 1.5h, 3h, .5h, 3.5h, 2h, 4h, 1.5h, 2h, 4.5h, 1h, 6h )
Horizontal Stabilizer DONE!: ~28 hours spent, 3 pieces replaced ( 3h, 2h, 2h, 2h, .5h, 1.5h, 3.5h, 1.5h, 5, 4.5, 2h, .5h )
Rudder DONE!, minus horn : ~16 hours spent, ( ~8h, ~8h )
-----------------------
Total Done: ~135.5 hours