Aircraft Maintenance

[JimD]

It seems that the two biggest tow plane maintenance issues are landing gear and exhaust systems. Broken hinges, servo wear, and covering are the next big three. Since Charlie's event is coming up quick, we needed to do some preparation. The Porter developed issues at the Muncy event and we thought we had them solved for Cumberland, but not completely. Seems my canisters got carbon buildup.

I think we have found the way to clean them out, but we decided not take any chances so a brand new set is being installed. While we were at it, we decided to tweek the right axle. Seems the alignment between the two wheels was not quite the same in spite of previous attempts to fix the issue.

[Asher Carmichael]

Jim,
Did you get kicked out of the workshop? :-o
And don't forget struts........

[JimD]

Asher, my workshop is in the lower level of my house, so instead of carrying the entire plane down the steps, I work out of the back of my truck in the garage. Gives me practice for doing field repairs! 😉

[Tom]

Now if you had a trailer with a table saw and drill press you would never need to walk those stairs again! Just saying........8-)

[gunny11]

A happy and healthy tow plane is a well-maintained tow plane. It keeps us glider pilots in the air. thank you for your efforts of keeping up the maintenance on your fleet in tiptop condition.

[JimD]

Okay, landing gear adjusted (needed two large C-clamps) and new canisters installed (needed Philips screwdriver, metric hex wrenches, and slip joint pliers). All tools mentioned are standard things I carry in my truck when attending events.





New 2-blade 27x11 Falcon prop installed...the reason DA says caused my initial problem was running too much prop for the application. Engine could not run at efficient rpm and therefore too much carbon in exhaust with resulting canister issue restricting exhaust outflow.

[Asher Carmichael]

So, what prop did you have previously, or did I miss it?

[JimD]

Asher,

I was running a Mejzlik 3-blade 27-12TH. Nice and quiet, but limited rpm which was further limited by the load of towing. DA says I need more rpm's to keep everything happy...or go to tuned pipes and keep the original prop.

[stevekremer]

Glad you got it figured out Jim. See you in Delaware.

Steve K

[JimD]

Today was Decathlon day, had to fix a covering seam failure along the bottom right side of the fuselage. I had to use package tape to hold it together during the Cumberland event. The gear was slightly bent from several less than ideal landings late in the day Monday when the wind became a little turbulent just off the end of the runway.

Added the N number graphic and fixed some problems with the black fuselage stripes.

[JimD]

How about this nice new graphic? 😎

[lenb]

I'll second everything Jim says. It really takes a lot of time as well as a fair amount of money to keep these tugs in the air and ready for service for an entire weekends event.
Kudos to you Jim and all the other tug pilots who have stepped up and shelled out $ to help keep us all airborne.

Since most tugs will do more takeoff and landings in a single weekend at an aerotow than they will ever do in the life of a sport flyer, we have a tendency to put the critical parts to the test.
Even simple things like tires and wheels become and issue. Tailwheels are a constant pain, and of course forget wheel pants.
Stock landing gear rarely, if ever, holds up to even the most gentle of thumbs, so we typically invest in after market landing gear from USA companies like TNT .

There's been some talk amongst tow pilots to double or event triple the cost of a tow, but for now we'll keep it the same its always been. $0 soon to be $00 and possibly $000


See ya at the field!!!!


Ps.

TOW LOOPS IN BEFORE GETTING TO THE LINE!!!!!!!

What? who me? it must have fallen out!!

LEN

[JimD]

The Decathlon now has 39 hours of flight time. Averaging 20 launch cycles per hour, that means the landing gear has been subjected to about 800 landings! Many in windy conditions that challenge the flying skills of the best pilot...but that is all part of what I love about this part of the hobby. Seeing the sky full of sailplanes makes my day. These last six years living the life of a tow pilot has produced the best memories of all the years I've spent flying R/C.

[JimD]

Well, I took the boys to the field to test them out after their maintenance visits...sure was nice having the shade of the new hangar to assemble them.




The Porter got new canisters and a new prop...wow, the performance increase was stunning! We had been running a Mejzlik 3-blade 27x12TH prop and we switched to a Falcon 27x11 2-blade.



We tried a different prop on the Decathlon, the one DA recommended for aerotowing using the DA-120 and MTW 75k canisters. It is a Mejzlik 2-blade 28x10 EVO. This series is light weight but has a wide blade. We got a small increase in rpm's, but overall it seems to run quieter than the previous Mejzlik 28x12 2-blade.

[ARUP]

Here is proof of the wear and tear these airplanes take whereupon field repair is mandatory. Note the lush, soft and taller grassy spot Jim has chosen. lol