Da40 purchase

[Hans]

I am in the market for a 40. Besides the standard pre-buy, is there anything else to be aware of BEFORE buying ????

[ihfanjv]

The DA40 is a great aircraft. Like all aircraft, it is not perfect.

Beware of the:

(1) Skin-spar AD affecting most pre-2008 DA40s and many 2008 DA40s

(2) Nose gear AD affecting most DA40s (very expensive to replace)

(3) 1000 hour very expensive mandatory inspection that includes:

- Cable replacement requirement
- Wing removal, fuel tank removal and inspection

(4) Delamination and corrosion within the composite in locations where any hole or through-bolted/screw hole exists in the composite

(5) Questionable reputation of the 3 blade "composite" (aka wood wrapped in fiberglass) MT prop

(6) Porpoising issues relating to KAP140 equipped aircraft (not a problem with GFC700 aircraft)

(7) Powerflow related issues, including:

- seized fasteners
- cracks/defective welds
- deterioration of the internal baffling

(8) Rear door hinge cracks resulting in the unscheduled departure of the rear door

(9) Crazy overhead lighting that overheats or times out spontaneously making the overhead lighting virtually useless

(10) Plastic window vent latch the breaks, and breaks, and breaks...

(11) Strange design where the dashboard shakes like all heck is breaking loose during startup and shutdown that I am convinced causes infant mortality to many (if not all) of the dash mounted electronics, most notably the backup AI (that is an expensive one!)

(12) CG issues relating to the 50 gallon tanks and location of the TAS600 box in TAS600 equipped aircraft (there are two places the TAS600 can be installed)

(13) LRU rack overheating - it is possible to load the baggage area in such a way that the LRU vents fail to properly vent causing overheating for LRU mounted electronics

(14) Heatstroke in the summer months due to bubble canopy that gives you the amazing view

I am sure I am forgetting a few things - others on the board will be sure to add and get you up to speed. Other than the issues listed above, another issue relates to the risks associated with a limited number of diamond-authorized service centers that creates lock-in for the diamond owner resulting in premium priced maintenance costs. Cirrus owners are similarly affected. Contrast Piper or Cessna owners that can take their aircraft to virtually any A&P for routine maintenance (although this, too, is changing with the G1000 equipped aircraft in the Piper and Cessna fleets).

Good luck on the aircraft hunt!

[Joey]

The experiences each of us have had with the DA40 vary a great deal.
(1) skin spar was a one time occurance and very few instances of problems were noted in the forums. It takes about an hour to do if not already done.
(2) not sure about the nose gear AD on later models.
(3) wing removal is also not a catastrophic event. It takes about 10-12 hrs depending on the shop.
(7) some powerflow issues are related to inexperienced shops not inspecting the power flow at annual correctly. There are some specific proceedures to follow that will help keep things from seizing.
(8) the rear door AD was a one time event and only took a small amount of time to investigate and fix in most cases.
(10) some have had repeated irritating latch failures, others have had zero problems. There are some aftermarket solutions.
(12) The base models don't have TAS600, they use the TIS built into the G1000.
(13) this is the first I've heard of LRU vent issues.
(14) But the view, keep remembering that! Alternately the ArticCool is a cheap solution or you can get Premier to install an AC, but plan for it when you finance your purchase.

As the fleet gets larger, local shops are getting more comfortable doing repairs. Garmin has a strangle hold on their repairs no matter what the airframe is. I suspect that will change as glass panels become more and more common.

Another weak point has been the aux fuel pump with lots of chatter on the forums about premature failures. The pump in now on the "C" model and a new alternative to the Dukes pump has just come out or is in work at about half the cost.

[Robin]

Hans

Re the rear door. Always open this door carefully. Do not allow it to be blown open by the wind. Have had this repaired.

Agree re the MT 3 bladed prop. It is not tough as the Hartzell 2 bladed prop.

However a great plane to fly

Fast I plan on 140 TAS

Economical 32- 36 litres per hour

No regrets for my purchase

Cheers

Robin

[Tommy]

The DA40 is a great aircraft. Like all aircraft, it is not perfect.

Beware of the:

(1) Skin-spar AD affecting most pre-2008 DA40s and many 2008 DA40s

(2) Nose gear AD affecting most DA40s (very expensive to replace)

(3) 1000 hour very expensive mandatory inspection that includes:

- Cable replacement requirement
- Wing removal, fuel tank removal and inspection

(4) Delamination and corrosion within the composite in locations where any hole or through-bolted/screw hole exists in the composite

(5) Questionable reputation of the 3 blade "composite" (aka wood wrapped in fiberglass) MT prop

(6) Porpoising issues relating to KAP140 equipped aircraft (not a problem with GFC700 aircraft)

(7) Powerflow related issues, including:

- seized fasteners
- cracks/defective welds
- deterioration of the internal baffling

(8) Rear door hinge cracks resulting in the unscheduled departure of the rear door

(9) Crazy overhead lighting that overheats or times out spontaneously making the overhead lighting virtually useless

(10) Plastic window vent latch the breaks, and breaks, and breaks...

(11) Strange design where the dashboard shakes like all heck is breaking loose during startup and shutdown that I am convinced causes infant mortality to many (if not all) of the dash mounted electronics, most notably the backup AI (that is an expensive one!)

(12) CG issues relating to the 50 gallon tanks and location of the TAS600 box in TAS600 equipped aircraft (there are two places the TAS600 can be installed)

(13) LRU rack overheating - it is possible to load the baggage area in such a way that the LRU vents fail to properly vent causing overheating for LRU mounted electronics

(14) Heatstroke in the summer months due to bubble canopy that gives you the amazing view

I am sure I am forgetting a few things - others on the board will be sure to add and get you up to speed. Other than the issues listed above, another issue relates to the risks associated with a limited number of diamond-authorized service centers that creates lock-in for the diamond owner resulting in premium priced maintenance costs. Cirrus owners are similarly affected. Contrast Piper or Cessna owners that can take their aircraft to virtually any A&P for routine maintenance (although this, too, is changing with the G1000 equipped aircraft in the Piper and Cessna fleets).

Good luck on the aircraft hunt!

Wow!!! After that intro to the DA40 I think I better sell mine before things really start going wrong.

[Jean]

Hi Hans,
None's list is quite exhaustive and maybe discouraging.
We bought a 2004 G1000 KAP 140 and the only squawk we had from the list is the passenger door hinges cracks. They were replaced (though I am not sure now that it wasn't only a cosmetic problem, there's a thread on the forum). Don't know how many rear doors departed because of that problem, one or two may be ?
(1) No problem with wing spars,
(2) No problem with Nose Gear AD,
(3) We had a wing removal for fuel tanks hoses replacement: not catastrophic. The rudder cable replacement is a 5 year issue, not a 1000H issue,
(4) No delamination issue,
(9) We had the overhead lighting issue, I just fixed it. Not much you can do about that in pre buy: they're all clumsy.
(10) we never broke any latch, be careful when you use the tempest windows, but it's a good idea to check if there is any crack during the pre buy,
(11) The dashboard shakes at shutdown, especially with the two blade Aluminium Hartzell but I never heard about avionics problem related with that. There tricks to minimize shaking at shutdown.
(13) Never heard of LRU rack overheating either. Not much you can check in the pre buy there.
- We had a propeller governor issue (AD, search forum), only very few DA40's were concerned. The check was payed by the factory but we had the shipping and some manpower cost. So check if there's no Prop governor AD.
- We now have a fuel pump failure, frequent issue, ours had 800 hours but many fail well before, so check the fuel pump time.
- We didn't experience porpoising in rain with the KAP 140. Check if the KAP 140 SB are addressed, but if you can, choose a GFC700 equipped model.

We are very happy with that plane and consider it as reliable and very pleasant to fly. No regret !
Good luck

[ihfanjv]

The DA40 is an excellent aircraft. But it has issues (like all aircraft). It is, bar none, the safest GA aircraft ever created. It is also very fun to fly. Years ago, Diamond used to boast "the DA40 has no ADs, unlike Plane X" - they don't make that claim anymore.

Regarding the skin-spar AD, for clarification, this AD is a result of the factory failing to use the correct amount of bonding agent between the spar and the skin on the top side of the wings when the parts were joined prior to firing in the autoclave. The issue affects most pre 2009 DA40s. The "fix" for the AD is to drill holes in the wings and inject resin to fill the voids - I will leave it to the composite experts to opine on whether or not that is really a fix. Even if it is a fix, it is an ugly prospect! Drill dozens of holes in each wing, inject resin in one hole until resin comes out of the adjoining hole, repeat as necessary. Then, close up the holes, grind and sand them down, then repaint the wings. I am curious as to what these wings will look like in 5 years, with variable stresses, and temperature shrinking and expanding of the wings. As nobody really talks about this issue, this AD is probably just being ignored in the DA40 fleet.

On the nose gear AD, this is a periodic inspection for most aircraft through DA40.643 (through the middle of 2006?) due to cracks. The only way to permanently comply is to replace the part - something like $6,000+. Chances are that it will eventually crack (or the service center will refuse to sign off on an inspection), so your choice is to pay as you go for the inspections until you inevitably have to pay for the replacement part, or take the hit early and replace the part.

I stand corrected on the cable replacement – that is a 5 year item. This board thoroughly addresses that issue and DIY workarounds. The 1000 hour is the wing and tank removal periodic inspection.

Almost every Diamond I have seen has some delamination in areas where a hole is drilled through the composite. The only ones that do not are those aircraft that never ever see water (no rain, no washing, no humidity). This is not a Diamond-specific problem; it is a composite aircraft problem.

I know of one DA40 that had an in-flight departure of the rear door; I have heard there are others. This can be cured with the MSB fix for the hinge.

I have seen AI failures in newer low-hours DA40s that I suspect is caused by the shaking panel. I have seen problems with G1000 panels that do not seem to occur with G1000 installations in other aircraft. The AI costs thousands to overhaul (not including AOG time). The G1000 swap-outs are not cheap either. This is certainly more of a problem with training aircraft that start up and shut down many times a day, rather than personal use aircraft. But, the first time an experienced pilot sits in a DA40 and sees the panel shaking, rattling, and rolling that pilot will inevitably look at you and say "that can't be normal" (it is normal in a DA40).

I have personal knowledge of an LRU failure that the service center blamed on "covered LRU air vents caused overheating."

I have not experienced the fuel pump issues, but this board addresses those issues thoroughly.

[Tommy]

It sounds like you have an ax to grind.
I own my own 2007 XLS and have not experienced any of the problems you describe.
I have also flown many 40s, analog and G1000 of varying years and have likewise not experienced anywhere near the problems you are allegedly having.
From a maintenance and insurance stand point I don't know of a like airplane that can match its low cost.

[ihfanjv]

Definitely no ax to grind here. I think the DA40 is a truly great aircraft. I provided a list of the objective issues with the aircraft (except for expressing my personal unsubstantiated belief that the shaking panel breaks things, which I note as a subjective opinion).

A potential buyer asked "what do I need to know about the DA40." I provided a list of the known potential issues for informational purposes. I would do the same for any aircraft, and for most the list would be much longer!

[Tommy]

Definitely no ax to grind here. I think the DA40 is a truly great aircraft. I provided a list of the objective issues with the aircraft (except for expressing my personal unsubstantiated belief that the shaking panel breaks things, which I note as a subjective opinion).

A potential buyer asked "what do I need to know about the DA40." I provided a list of the known potential issues for informational purposes. I would do the same for any aircraft, and for most the list would be much longer!

Nope. Not buying it.