Annual frustration

[mhoran]

Your experience in the past few years sounds very similar to mine. I've had continued trouble with the lower cowling paint, starting back in 2018. The design is generally terrible, especially with the Power Flow. Fortunately SouthTec keeps fixing it for me at minimal cost, but it's getting frustrating to have them fix it every time I'm down there. I don't understand why this is a persistent issue for some and others not.

Also been there with the wing root corrosion. We have it too, but haven't fixed it yet. We passed the 1000 hour bonding check without addressing it and it's mostly a cosmetic issue, unless it's bad enough to cause that inspection to fail.

We also keep the plane outside. I think this was partly the reason for dry-rot requiring new tires last year. We now have the fairings back on so hopefully that helps. They're looking a lot better. The corrosion I think would happen even if in a hangar but near the ocean like we are. Not much getting around that -- it's a terrible design on Diamond's part.

[blsewardjr]

Dan- Some of your costs seem unusually high compared to mine. I replaced my NLG this year for 4k in parts and shipping and $300 in labor (vice your 7K). I bought the strut from Premier in Florida. Also, although it was four years ago versus your replacement this year, my MLG tires were $530 and labor was $425 (vice your 1.5K). Savvy might help you in this area. Bernie

[waynemcc999]

I agree with the suggestions to use Savvy. You describe yourself as not mechanically inclined. You really need an advocate that has deep knowledge of the maintenance business and of aircraft maintenance in general. Less is more in aircraft maintenance but that is obviously counter to profit making. Get an advocate.

I totally agree with Lance... "Less is more in aircraft maintenance". I've used SavvyMX for 10 years since I bought my 2008 DA40 and I believe the cost has been worth it in avoiding unnecessary work... and thereby avoiding "maintenance-induced failures".l
Wayne

[astaib]

Thanks to all for your thoughts!

I also had a 2001 steam gauge no autopilot version and I never had this kind of bill!
Can you tell what is corroded? And what had been changed in the last 3 years and also what is planed for this year?

In 2020, the big items were problems discovered during the mandatory chapter 4 static and bonding checks (about $8K), as well as a muffler rebuild, a new battery, and a (failed) attempt to solve a VM-1000 fuel pressure sensor problem. Shop had COVID challenges along with big delays getting the bonding check equipment from Diamond Canada and the plane ended up out of commission for about three months.

In 2021, I did the nose strut replacement for around $7K. Long delays Austria -> Canada -> US. Down 2+ months.

In 2022, new shop found wing root corrosion ($3.5K). Also tried again on the fuel pressure issue, spent $1K on fuel pump, no luck. Went down a rabbit hole given that the original manufacturer of the VM-1000 is out of business and whoever bought them out doesn't seem to have a huge stake in continuing it. Concluded that I'll eventually need a new engine monitoring system but wasn't ready to spend $10K trying to find one.

This year, it's the 500 hour magneto check, plus muffler baffles messed up again ($3K), peeling firepaint from the lower cowling and battery cover deemed airworthy ($2K), new tires ($1.5K). I'm deferring replacement of fuel tank vent hoses and interconnect hoses as that was gonna be another $4K, as well as seat-belt replacement ($2K).

The corrosion is in the flap weight arms and aileron trim tab. Those are pretty minor items. My plane is outside all year long with Bruce Covers on the whole plane in winter, so I can understand why I had wing root problems and why corrosion would be a bigger problem.

I've looked at Savvy but will take a closer look now. Might be good just to have somebody on my side.

I see you are in the Northeast. I'm willing to bet your labor rates are higher

Yeah, that was part of the issue with shop 1 I think. I'm trying not to name shops because they're just doing their job and I get the business and liability issues from their point of view. Look at Flightaware for N270DS and you'll know which shop I'm using now. They're up to $129 an hour now.

But I got in an incredible trip around the country over the summer, which (nearly) made me forget about all of this nonsense.

Matt, I'm right there with ya - This is the reason I've stuck it out this long. This year I did 3 great trips, one southern route from Massachusetts to San Diego and back, one northern route to Seattle and back, and then a quick trip to Santa Fe and West Texas for the annular eclipse in early October. I love the trips. Even if I decide it's too much for the long run, I'll be hoping to get a Yukon/Alaska trip done for 2024. Perhaps Gaspe and Newfoundland as well. If that turns out to be the swan song, so be it.

Thanks again for your support!

dan

Hello Dan,

For the static Bonding, are you flying IFR or NVFR?

For the VM1000, did you contact Reggie on https://vmsupport.weebly.com/--vm1000-p ... ifier.html ?

Did you replace the battery with a Concord instead a Gill?

Did you replace the NLG with the D41-3223-10-00_2 version?

Can you explain where is the corrosion on the wing root? Is it on the intrados where the 3 little screws are?

Are your hoses worn or just due ?

Are the set belts worn or just due?

Arnaud.

[gregp]

I've looked at Savvy but will take a closer look now. Might be good just to have somebody on my side.

If you are looking into it, be aware they are raising prices Jan 1. They helped with a pre-buy log review and reviewing a quote for a long list of “first annual” and pre-buy discrepancies on a new to us DA40 using their SavvyQA service. I’m not an expert, so it’s nice to have someone that we can ask questions and help make educated decisions.

[arksat]

I've had continued trouble with the lower cowling paint, starting back in 2018. The design is generally terrible, especially with the Power Flow.

Matt, can you give more details? I'm going to install PowerFlow next year so wanted to know more about the trouble you encountered.

[mhoran]

I've had continued trouble with the lower cowling paint, starting back in 2018. The design is generally terrible, especially with the Power Flow.

Matt, can you give more details? I'm going to install PowerFlow next year so wanted to know more about the trouble you encountered.

The PowerFlow tailpipe exits the cowling at a different location than the stock tailpipe (though PowerFlow has since replaced the stock exhaust.) Above the tailpipe there is a heat shield that protects the composite. However, on the bottom there is not. The tailpipe is attached to the airplane via a piece of neoprene. It is prone to slide side to side and stretch. I'm not sure if this is the reason for my issue, or just bad design in general. But since 2018 I have had issues with the tailpipe burning the bottom cowling, and with subsequent heat paint replacement, peeling of the paint requiring composite repair and expensive paint repair.

Some seem not to have as much trouble as others. Unfortunately the exhaust must come off at each annual, so if you think you get it right one year and experience no damage, it may be reinstalled incorrectly the next year and cause damage. Overall the PowerFlow is a huge improvement over the stock exhaust, but this one issue is quite an annoyance.

Oddly we did not have an issue for the first few years of ownership. It only became an issue from 2018 onward.

[arksat]

Thanks for the details, Matt. I'll monitor and share it here if I encounter the same issue.

[Rich]

When installing/reinstalling (after service) the Powerflow requires attention to detail in the positioning of the muffler. I've found that shops are not careful about this. The muffler has to be free to move a bit, as the engine moves around a bit in its mounts during operation. The rubber hangers can wear out, but I only had this actually happen once. Sliding up over the end of the firewall mount was the culprit. It's worth checking the mount at each oil change and even replacing it whenever the PF is serviced - generally at annual.

Check before flight by seeing how freely it moves around. It shouldn't get closer than about an inch to the nearby surfaces. I've found I've had to be very careful about the rotational angle at the ball joint between muffler and collector and the positioning of the bracket that connects the muffler to the collector. The position of the bracket longitudinally and radially is critical. When mounted, the muffler should be pointed somewhat away from the right side of the plane.

I've found the straps PF provides have lasted well, with the exception of the one time the thing slipped over the outside edge and got torn up. I keep a couple of spares around in case I want to change one on condition. The pre-drilled holes in the straps are positioned to hold the muffler with correct vertical clearance between the cowling and the lower edge of the firewall. But the straps are a bit narrower than the mounting bar and can slide on it. I've put a kind of shim in place to keep it from sliding outward.

[Charles K]

If you perform MSB 40-074 (which is an AD) the aft spar reinforcement you can greatly extend the MSI intervals....

By further testing and investigation it was discovered that the fatigue strength of the aft main spar in the cabin area does not ensure unlimited lifetime. This Service Bulletin prescribes the reinforcement of the aft main spar to correct this condition. As an additional benefit the reinforcement is the basis for the Major Structural Inspection interval increase to 6000 hrs since new and every 4000 hrs thereafter.