Saturday, April 26, 2014

Project Complete!

After many hours, I finally finished the cowling repairs I've been working on! In my last post, I shared some photos of the corrosion that I was cleaning and removing on the engine cowling of a Cessna 206 owned by Missionary Air Group. Wherever I removed corroded material, I had to make repairs. Well, here's the finished product!

I know it may not look like much, but this was a challenging repair, especially for someone who is new to this type of work. It involved fabricating 12 new repair pieces (some of them are hidden beneath doublers) to match the shape of the existing channels or fit over them as reinforcements. The curvature of the pieces also had to match the curves of the cowling quite closely, so that the cowling would fit correctly when installed into position, and so the nose bowl would fit properly to the front of the cowling. The repair pieces also had to be riveted into the existing structure in a manner that would give the cowling sufficient rigidity.

As I mentioned in the last post, a replacement engine cowling would cost over $5000 (or $10,000 for the right and left) if purchased from Cessna! Because of this, it was worth investing many hours of my time. It was rewarding for me to finish this project, and to make a small contribution to getting this airplane back into missionary service in a condition that will allow it to fly for many years to come!

A few of the repair pieces prior to installation.

Wednesday, April 16, 2014

Performing Surgery on MAG's 206

It's always exciting to be visited by pilots and other representatives from the organizations that MMS serves. It's encouraging to hear stories from the field, and to gain a better understanding of how our work at MMS impacts missionary work around the world. For two weeks, Sean Donnely from Missionary Air Group has been at MMS. We had the opportunity to hear about the work that MAG is doing in Honduras and Guatemala, and Dale and I had the opportunity to show him the work we have been doing on MAG's Cessna 206.

Cowling after modification and repair.
Lately, I have been removing corrosion from the cowling of the airplane, repairing the affected areas, and making some other modifications. The first photo shows the half of the cowling I completed last week. After cleaning it and stripping the paint, I moved the oil check door (to prepare for an engine conversion), which involved cutting a hole for the new door, fabricating some shims, riveting the door in place, then patching the hole where the door was previously located. I also cut out an area of corrosion in the skin and installed a flush patch, and made a reinforcement for another area that had been damaged.

The other half of the cowling had significant corrosion, as shown in the pictures below. At times I've felt like a surgeon, carefully cutting out this "cancer" that will continue to spread if it's not removed, trying not to damage the parts that are still in good condition. When I'm done, it will bear some scars (patches), but will be in a condition to fly for many more years. I'm investing significant time and effort in this project, and it has been a great learning experience for me. More importantly, my repairs will allow the airplane to return to service as an air ambulance in Guatemala, in an airworthy condition.

You may wonder why, with such extensive damage, we don't just buy new cowlings instead of investing weeks of our time to repair them. Well, it turns out that each cowling is priced at over $5,000! Even in good used condition, the two pieces would cost several thousand dollars each.

One of the things I love about MMS is that even in the course of my apprenticeship, I am making a meaningful contribution to the missionary aviation community. In the process of learning how to do this sheet metal project, I am not just developing my skills as a mechanic; I am helping to save potentially thousands of dollars for missions organizations like MAG, and to get their airplanes back on the mission field.

I look forward to finishing my repairs soon, and I'll share pictures of the finished product when that time comes!