Some discussion with fellow pilots (well informed as usually participating in crash investigations) have suggested that da62 crash after TO was due to an electrical failure. Reason for this is still unclear, bit an easy reason would be that both alternator were off.
Yes, thanks for correcting.
As Emir wrote in a previous post in this thread , the HP failure and subsequent OEI landing was with a DA42-VI, not DA62.
Peter wrote:
Is this Diamond issue getting more common or is this just typical clustering found in sparse data?
The last one (DA62 OEI landing) is related to known HP pump issue. MSB for one batch of these pumps has been issued requiring replacement and it’s seems that this pump wasn’t supposed to be in the engine at all (MSB was issued before the aircraft was delivered to the owner).
For the crashed DA62 and DA50 I don’t have any details except that DA62 crashed just after refuelling – however, still no feedback on fuel analysis.
What’s worrying is that all three aircrafts were brand new.
My estimate is that it’s a matter of statistics.
Is this Diamond issue getting more common or is this just typical clustering found in sparse data?
But in general, if you have an engine so dependent on electricity having an in-engine backuip not reliant on anything else is a good idea.
That’s what the gut feeling would perhaps tell you, but if you analyze the concept of a mechanical backup of an electric system, this is very seldom true.
The first F-100 engine in the F-16 had a mechanical backup computer. A true marvel of a hydromechanical computer. But it didn’t take many years before they were all replaced with redundant all electric units.
aart wrote:
I don’t know whether in the meantime a better solution has been introduced.
Yes, better engines than the original Thielert’s ;-)
The engine stoppage was triggered by a simultanous reset of all ECUs, which was triggered by a short undervoltage transient. Instead of having a power backup on the engines, this could be prevented by adding an inrush current limiter to the gear motor, or possibly a better (faster) regulator if the alternators are big enough.
But in general, if you have an engine so dependent on electricity having an in-engine backuip not reliant on anything else is a good idea.
If you mean the issue that when you had (a) a completely dead battery and (b) retracted the gear the engines woud fail? No, that was fixed by fitting a backup battery to the ECUs and the fix was made mandatory by an AD, at least in Europe (don’t know if FAA followed suit).
Does the DA42 still have that issue with departing with a flat battery?
That was quickly fixed by adding some small back-up batteries, to be annually replaced. I don’t know whether in the meantime a better solution has been introduced.
