# How does the safety record of the twin piston Diamond DA-42 compare to the single piston DA-40?

Its fairly well known that the Diamond DA-40 has one of the smallest fatality rates of any GA plane. The Diamond DA-42 is a twin engine aircraft with a very similar design to the DA-40.

Now, it has been shown that, in general, twin aircraft are not that much safer than single because the added complexity of operation removes the added safety from engine failure. However, the DA-42 is much easier to fly with FADEC control of the engines and a lot of automation.

Is the DA-42 safer than the DA-40?

• not that much safer than single because the added complexity of operation removes the added safety from engine failure. Source?
– ymb1
Sep 2 '16 at 20:23
• A huge amount has been written on the topic of single vs. twin. Here may be a start: flyingmag.com/wrong-worry-twins-versus-singles Sep 3 '16 at 0:27

So it appears that Diamond answered this question for me.

From this chart, it would appear that the DA42 has a slightly higher accident rate, and of those accidents, even more are fatal (which makes sense due to the higher speeds). Still loads safer that the SR22 though, and I'd personally prefer the 42 over water as well.

I know its an old post, but I would add that to me its important to factor in the speed of the aircraft. Speed as in how far are you going to travel in an hour. If you factor in that for the same distance flown between points, the DA42 will get you there faster, then both aircraft come in at about the same accident and fatality rate.

It's not a perfect analysis, but it makes sense. It's not that the DA42 is more dangerous because the twin is faster, its simply that to accomplish the same mission you are going to be in the air for fewer hours in the DA42.

• I would note how this is not in favor of the DA42. If you have more accidents in less flight hours, your aircraft is less safe.
– Federico
Sep 17 '18 at 15:36
• @Federico, it depends on your goal: if the point is to get from A to B (as it is in most cases, esp. for DA42), then the proper metric is accidents per distance (km or mile). Here DA42 indeed may have an edge, even with higher per hour rate. (Needs calculation). For sightseeing, accidents/hour may be more representative.
– Zeus
Sep 17 '18 at 23:56