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Unread 08-11-08, 12:52 AM
stackj stackj is offline
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Join Date: Apr 2002
Location: Richmond, VA
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Boy! Are you ever right!

I accept your phra$e and rai$e you 42 kilobuck$!

I had a minor heart attack on Janurary third. That has grounded me for the last six months. I was fortunate, however, because my wife also flys the Skymaster. With her in the airplane, I was able to touch the controls and reduce the depression.

But then, along came rear engine and dual prop overhaul time. The airplane went into the shop on March 28 (12 days after your trip... Is there something in the air? - no, nothing in the air... at least not our birds). We were expecting to get the airplane back in six weeks. That would allow us to have it home two weeks before needing to tear it down for the annual. You can see where this is going!

14 weeks later, the airplane was ready to come home. A friend flew us to pick up our bird. We had obtained the ferry permit a little too early and it expired on the day we went to pick up the airplane. Jenny test flew the airplane (I couldn't go on the test flight since a ferry flight only allows required crew to be on the airplane - As a mechanic, I was not required.) Jenny brought it back for some fuel adjustments and then prepared to head home with it. On her takeoff roll the rear engine quit... Maybe the adjustments were not quite right!

The mechanics began running the engine to make further adjustments. They ground ran the aircraft so long that the oil thinned out and the rear prop went into feather. Well, it Was a hot day. We ended up leaving the airplane and our friend flew us back home empty handed.

The following week, another friend flew us to the airplane. Once again, Jenny test flew it. The indications and controls were so badly split between the two engines - like two inches difference in the mixture control positions in order to balance the engine gauges. This was fixed by adjusting the fuel controls on the front engine... Funny, we hadn't had any trouble with it.

Anyway, It was close enough that Jenny flew it home. How do you think it impacts your Aviation Deprivation Depression when your wife is flying your airplane home on a ferry permit, and you, the protective male mechanic, can't go?

Now the airplane is home and it's time to tear it down for the annual. Well, something went right. The only thing we found was a broken muffler bracket on the front left muffler. And what is this!!?? we actually had a new one in the hangar.

New bracket installed... Airplane re-assembled... weekend is here and we get to fly finally. We did about a three hour flight. About halfway through the flight, the gyro in the HSI decides to tumble. We were VFR, but were about half way across the Chesapeake bay with low visibility... i.e., no shore line visible. (Did you know that a Garmin 530 makes a wonderful heading indicator?)

After arriving home we started tracking down a replacement. The following week we were at Oshkosh (which was previously planned) and we were able to track down an overhauled NSD-360. We had to order it through our avionics shop as the overhauler would not sell directly to the customer. I removed the old one, took it to my dealer, picked up the new one and headed home with it (This was only an 85 mile drive each way.) I installed the instrument and re-assembled the panel. I powered up the avionics buss and everything looked great. I reached for the heading set knob and discovered that it would not turn the heading indicator. Arrrggghhh!

I removed the HSI and tried adjusting it outside of the aircraft. It would move the compass card slightly, but continued to slip badly.

I drove back to my avionics shop and demonstrated the problem to the radio man... or tried to. Of course, the compass refused to fail in his presence. Fortunately, he believes that I am pretty honest, and he is pretty patient. He had not yet shipped back the original failed unit, so we were able to compare operation of the two units. I discovered that holding the OBS knob while turinig the compass card knob would duplicate the failure on the overhauled unit. That failure would not occur on the original unit. We packed the old and new units up for shipment from the right coast back to the left coast (one day air, of cour$e.) I called the overhauler and was able to describe the symptoms to one of their technical people. This was a good move, as they had been unable to duplicate the failure. This method of creating the failure became known as the "NNN Avionics method of troubleshooting". They were able to identify and resolve the problem.

The overhauled unit was shipped back to the right coast (It now had 9000 more miles on it... more than the airplane it would go in will get in the next three months... if we fly a lot.)

Once again, I installed the HSI, re-assembled the panel and tested the HSI. All appears OK. We flew the airplane both Saturday and Sunday (about 9 hours total) and... IT WORKS!

Is there any such thing as Manic Aviation Deprived Depression???
__________________
Jim Stack
Richmond, VA
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