Robin DR401 with CD155 reliability (and diesel v. Lyco/Conti engine reliability)

Thanks for the report, luckymaa.

The other owner I am aware of who is active here is @nealcs

That aircraft is, in many ways, a “new” design.

I think it is fair to say that your’s is a typical experience of customers of “new design” aircraft. I had the same experience when I had one the first SR20s in Germany. However, in my case (and that also seems typical), after about 2 years, the streak of technical problems ended and it then became a very reliable aircraft.

BTW, I think 500 hours in 2 years and 2 months is slightly on the low side for such a plain vanilla PPL aircraft, bought new by an aeroclub.

Sorry to hear this luckymaa. For comparison we’re about 1 year and 100 hrs in to ownership of an ex-demo DR401 which had sixty hours or so when we got it, and we haven’t had a single day AOG. Even the battery stood up to being grounded by a few weeks of bad weather. At the annual (100hr check), which was done same-day at LEA in Elstree, we only needed one annunciator bulb beyond the timed-life components and fluids.

Has been very good value for money enjoyable and reliable flying. We’ve also been astonished at the performance of the fully coupled autopilot which flawlessly flies an RNAV almost down to the threshold. Though we’ve lately had some GPS dropouts so think we have a loose connection to the GTN 750 arial and it is going in this month to be looked at.

We had very good service from Robin last time we went to the factory and very swift helpful (free) advice to get us back in the air when we accidentally screwed up some settings on the GTN – so far so good – can’t praise them more highly. I’ll let you know how the next visit goes.

Hello all

Started a few weeks back my CB-IR at a local FTO (french aéroclub, non profit organisation).
They were using a DR500-200 President but switched to a DR401-155CDI (and sold another DR400 for a DR400-155CDI). Both equipped with G500 / GTN650.

Mechanics who are used to maintain classics DR400, says there is no standard in the wiring process of new APEX Aircrafts, as if each mechanic building the aircraft had is very own style.

The DR401 have had a few problems since the beginning (flaps which needed a breaker reset after startup / Engine cooling problems). It was resolved after a few complications and the last one and a half month went smooth.
Two days ago, aircraft went back from the 100hrs mechanical visit.
30’ flight. Everything OK.
We jumped in with my instructor for a local training flight : holding patterns, IMC, by night.
OAT +8°C

After an hour flight, we came back for an NDB procedure. A few seconds after reaching minimas, the CED Alert came ON.
Coolant Temperature high (Red)
10 seconds later, CT was back to normal, but Oil Pressure was low (yellow) and both FADECs alarms went flickering. Pretty frightening considering if both FADECs fails, engine quits.

Attending we were in position for landing and engine was running normally, we declared no emergency PAN PAN and we initiated no actions on the systems.
Maybe a FADEC reset would have corrected the problem, but in doubt, we preferred land with alarms and engine, than without alarms nor engine.

On post-flight check, we saw few blue drops were sustaining under the engine. Probably coolant liquid.
Aircraft is grounded until further notice.

We were happy this happened on short final, and not a few minutes back, 2000’ IMC by night.

luckymaaa wrote:

this sounds familiar to us. The same procedure helped a while with the flaps. The coolant problem we know very well too. up to now about al 50-70h a new cooler was necessary. Neal seams to be more lucky…

Manufacturer requested the engine to be sent to Germany for inspection.
No clue on the delay before we can put the aircraft on schedule again.

Very sad to hear!

I am really impressed people here write openly about issues with their aircraft. It’s really admirable and is great for the whole GA community.

Peter: there are two ways to deal with one’s aircraft problems.
One could hide like a wounded animal and fight the lack of information / incorrect information on one’s own.
This means being left to challenge the “experts” with one’s own limited knowledge and experience.
It can get really costly, but the “benefit” is that you are not telling the world – and a potential buyer – how much trouble you have with your plane.

The other option is to share the issue and ask for support from the community.
In my case, I decided to do that, not worried about impacting the (eventual) resale value of my plane because I had every intention to fix the issues once and for all.
I have however found out that it was quite difficult to manage some of the input. People tend to become quite radical when the solution is not obvious or when opinions diverge and at one point I decided that the discussion was not going in the right direction.

Lesson learned: If I ever post to help a fellow pilot, I will make sure that my contribution is towards experience sharing/diagnostics/fix and nothing else – just answer the call for help to the extent possible.

Message to all of you who are having trouble with some Lycosaur, some ECU, flap system or retractable landing gear:
ALL of our planes have these problems to varying degrees at some point in time because ALL of them are essentially built like prototypes… if you got into plane ownership without factoring in the “oops” factor, you need to change your mindset and… start budgeting for it.
That’s all. These things fail, fortunately most failures are not life-threatening and there are some pretty sharp people out there willing to help, and we should be open and call for help.
This said I am very sorry to hear about these issues here , cannot contribute but just wanted to encourage the open discussion.

Agree, flyingfish. Our aircraft are basically prototypes, much like boats, and it shows up in the squawks that ANYONE will get, sooner or later.

Adding to what you say about helping each other, we may also wish to put pressure on our suppliers. I know it’s not easy, because you have no choice but them in most cases, but that does not mean we should not fight.

I find it outright ridiculous that an engine supplier just tells a client to ship his engine to the factory. Call me old-fashioned but I expect the company to take pride in their product and therefore feel a responsibility to help out a client. So, ideally, they should have a pool of a few exchange engines that are ready for shipment the next day. And send an engineer over to look at the problem, better still going there in a van with that exchange engine, and either try and solve the problem locally (maybe just a leaky hose?) and if that is not possible, mount the exchange engine. Or at least talk to the client about this possible solution instead of just tell him to ‘send over the engine’ and ’don’t call us, we’ll call you’ kind of situation.

Yeah, yeah, I know. ‘GA is small, suppliers make no money, there is often no commercial pressure involved on the side of the client’ and all kinds of other arguments why we sometimes are treated badly, and that we cannot expect to be treated like the airlines, where there is a magnificent system in place of cooperation between the maintenance dept of the airline and the aircraft/component manufacturer to make any AOG situation a non-event.

But isn’t that a chicken and egg situation? If I were running the Conti Diesel group, I would come to conclusion that the CD135/155 are fine products but that there is (understandable) still quite some skepticism about them, in spite of clear improvements over the years. There is more complexity, so more opportunities for things to go wrong (water cooling, lots of sensors, ECU’s, although lots of failures are spurious sensor issues, a nuisance nonetheless). So I would put money into constant ruggedization of the design, but (in parralel) have an excellent Customer Support system in place, because I think that there is no better marketing than excellent customer support. Let’s face human psychology: most of us (except for some grumpy ones) will feel annoyed by some technical glitch that means you are grounded, but feel a lot of satisfaction to see that every effort is made to resolve it quickly. To the point where the joy of it seeing repaired quickly may even be bigger than the initial annoyance. If your mindset is correct (see Flyingfish above) that ‘shit happens, get used to it’, but that you can count on a supplier that remedies it quickly and economically, the problem is soon forgotten. And so Conti could actually easily overcome any kind of skepticism by spending some money. Maybe reducing the marketing dept staff, no more or little aeroshows (or cleverly link up with an OEM) already makes the whole exercise of increasing the quality of customer support a ‘budget neutral’ event.

EuroGA is a great forum where we have constructive discussions. Manufacturers should use that. I suspect some read it, although they probably would not admit it? Maybe we need some sort of feed of certain threads to certain manufacturers? ;)