Tuesday, May 25, 2010 Spars and Seat to Repair Shops

Today I collected the keel spar and the seat and gas tank sling to take them to their various repair places. I had located Papa’s Shoe Repair in Waconia who was willing to repair the seat and sling. Shouldn’t be very difficult, according to the old guy running the shop.

I also took the old keel spar and the new replacement tubing to Victoria Repair and instructed them to reproduce the old spar with the new tubing. I explained about the forward and aft inner sleeves and the mid over sleeve. They said it should be ready next week. I wanted both things to be done before Memorial Day week-end, but it’s my own fault I didn’t get the parts to them sooner.

But there’s a problem. For some reason, I thought I should look at the old and new tubes for the leading edge spar and by comparing the wall thickness of the two and it looks like the new tube is thicker than the old one. There is no question about it. The new tubing is thicker. That means the I.D. of that tube has to be less than the old spar. So it won’t fit over the sleeve of the forward half of the left leading edge. I can’t verify that for sure until I take it up to the airport and try it. But it comes as a unpleasant surprise. I did not take the spar to Victoria Repair, so at least I won’t waste the money to have it duplicated until I unravel this mystery.

Upon checking the Demon 175 manual, it says very clearly that the leading edge spars are .058, which is what I ordered. So by doing the calculation, according to my reference, the 1 7/8 O.D . has an I.D. of 1.759. So with the normal slack of .009, the inner sleeve should be 1.750, which jibes with the manual. So I’m confused. Maybe there isn’t a problem after all, so that’s something to be determined. I just go with the straightened spar for now and replace it later if my suspicions prove out. I need to check out the wing as soon as I can; this has gone on too long.

Thursday, May 20, 2010 Shipment Arrives from AS&S

I received a call from the shipper that the order from AS&S had arrived. I had it shipped to John’s house since there was no way to receive it here at our apartment. There were several tubes of 12’ in length, so it would be cumbersome to move around. My original plan was to have John move the stuff up to the airport using his truck, but he was out of town and after maneuvering the cardboard tube that contained the tubing, I was able to get it into the car and got it up to the airport myself.

I kept the tubes for the spars here so I could get them over to Victoria Repair so they could reproduce the spars that had been bent. I also brought down the seat and gas tank sling down so they could be repaired. They had been cut by the EMT’s along with the tubing and cables. I’ll locate a shoe repair shop or something like that to have those repairs done.

Saturday, May 15, 2010 Order Rest of Tubing

I haven’t had much of a chance to make any progress with the Jetwing rebuilding project, due to many, many family birthdays (including my own) that inexplicably taken precedence over the rebuilding project. I did work up an order from Aircraft Spruce and Speciality for the remaining tubing, new AN hardware such as nuts , bolts, and washers, and a new seat belt and harness. The prices are by far the lowest of anything I can find in the Minneapolis area, so this has worked out very well.

Saturday, May 1, 2010 More Spar Questions

May day today (which is different from 'mayday! mayday'!) Don’t know what that means, but it is a nice day today, anyway. I looked over the keel spar carefully and tried to put the tape measure down the inside of the aft tube to see if I could detect the edge of the inner sleeve. I couldn’t tell with certainty, but it seems like the tape measure hung up on something some distance down from the cut-off part. By adding up all the numbers, it would seem that if the inner sleeve runs from the place where the tape measure hung up to the end of the spar, the length of the inner sleeve would be 30” and would strengthen the tensioning area. That makes sense. In an earlier e-mail to Larry Miller, he thought the inner sleeve might be at the attach point, but that is where the outer sleeve is, so it makes more sense for the inner sleeve to be at the tensioning area and the outer sleeve at the attach point. Of course after I measure and diagram the hole positions we’ll cut up the spar and I’ll verify the sleeve configurations. This was much more complicated than I anticipated, but I think I have a handle on it. The left leading-edge spar is not as complicated; just a single tube that will simply require the holes to be positioned in the right place.

Friday, April 30, 2010 Check Out the Wing Spars

Went up to the airport and brought down the keel spar and left leading-edge spar. The more I research the opinions of others who work with aluminum the more I’ve convinced myself that they are compromised and really should be replaced, not just straightened. I took the keel to Victoria Repair thinking that the main spar was made up of two pieces with an oversleeve splicing them together. The old guy at the shop tried to extricate the forward piece only to figure out that the spar was one whole piece. He cut the spar at my request just ahead of the oversleeve and looking down the length, determined that it is in fact one solid piece. The oversleeve is 18” long and wasn’t bent, so should be able to reuse it.

At the same time, I picked up the box that had the front wheel bracket and the two wheels with the hubs removed. Looks like they turned out well. I need to research the loads these wheels can tolerate to see if they’ll work on the Jetwing.

According to the Demon wing manual, there is an inner sleeve inside the keel spar someplace. I didn’t see any evidence of that for the spar I have. I don’t know if there was none, or most likely it’s a partial sleeve that is buried in the aft section that I couldn’t see. I will measure the length to get the exact measurement and then have Victoria Repair cut up the spar to see if we can find the inner sleeve and determine its dimension. I don’t think it would be a good idea to guess on the configuration of the keel and position the inner sleeve without knowing the exact specifications since it could affect the weight and balance of the wing. I also sent an e-mail to Larry Miller asking him if he knew anything about that. I also found a couple of places in MPLS that might inventory the larger tubing I need for the replacement of the spars. Anxious to see when they come back with.

Tuesday, April 27, 2010 Second Dual Flight

Don Lindemann called and said our scheduled flying day, Thursday, would not be good weather so suggested we fly Tuesday at 6:30PM. I drove to New Richmond after work at about 5PM and arrived about 10 minutes late because of rush hour traffic. Don forgave me and we flew for an hour all T&G’s at New Richmond airport. It felt good. Don thought I did OK, but when he endorsed my log book and saw that this was only the second time out, he was amazed that I had done that well. Should be able to do some greasers next time.

Thursday, April 22, 2010 More Machine Work

Took the box of parts back to Victoria Repair. The left side foot peg had not been welded on, and I also wanted him to try to get the hubs out of the bicycle wheels and see if they can be used on the Jetwing.