Diamond DA50
Joined: Jun 2006
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From: Maders UK
"The oxygen flow rate for four people, in these unpressurised planes, at 25,000ft, would be eye watering even with the Mountain High electronic demand regulators. You have to use masks, not cannulas, and in the end this does not represent any kind of practical mission capability."
Point taken, IO but you would file at a somewhat lower level (FL100-160) and climb above the Alps/weather etc.. for as long as you needed (say an hour or two) before coming back down again to your preselected cruise.
Nice to have access to that extra height band and be looking down on the clouds, not bumping around in the grey sleety stuff.
The alternatives for getting up higher (TBM/PC-12/Kingair) are an order of magnitude more expensive to buy and run (with the exception of the JetProp DLX which looks a bit of a chop-job in my opinion, costs far more per mile in fuel has far less payload/range capability).
SB
Point taken, IO but you would file at a somewhat lower level (FL100-160) and climb above the Alps/weather etc.. for as long as you needed (say an hour or two) before coming back down again to your preselected cruise.
Nice to have access to that extra height band and be looking down on the clouds, not bumping around in the grey sleety stuff.
The alternatives for getting up higher (TBM/PC-12/Kingair) are an order of magnitude more expensive to buy and run (with the exception of the JetProp DLX which looks a bit of a chop-job in my opinion, costs far more per mile in fuel has far less payload/range capability).
SB
Joined: Jun 2003
Posts: 13,787
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From: EuroGA.org
Agreed, SB - I was just trying to point out how "200kt TAS" is achieved, and that it isn't a realistic cruise speed at realistic levels.
I sometimes wonder why I didn't buy a TB21 instead. It does do less MPG at low levels (lower engine compression ratio), has about 2x the engine fund (bigger overhaul cost, due to a very rare IO540 variant), but with full TKS it has much more mission capability.
Perhaps I just too often see turbocharged planes sit in hangars for months on end........
I sometimes wonder why I didn't buy a TB21 instead. It does do less MPG at low levels (lower engine compression ratio), has about 2x the engine fund (bigger overhaul cost, due to a very rare IO540 variant), but with full TKS it has much more mission capability.
Perhaps I just too often see turbocharged planes sit in hangars for months on end........
Joined: Jun 2003
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From: EuroGA.org
I recall reading the DA42 would do 207kt.
Obviously that was TAS.
In the end it fell tens of kt short. One could speculate it was a number of factors
- use of computer model figures
- a prototype aircraft flying at way below MTOW
- MTOW itself rising as they put in equipment which they didn't think they would need
- drag rising due to antennae etc
etc
The real question however is not whether the manufacturer of something brand new will meet the advertised specs; it is whether you want to pay $600,000 or so to be an unpaid tester
Not getting 207kt is the least of peoples' problems.
Obviously that was TAS.
In the end it fell tens of kt short. One could speculate it was a number of factors
- use of computer model figures
- a prototype aircraft flying at way below MTOW
- MTOW itself rising as they put in equipment which they didn't think they would need
- drag rising due to antennae etc
etc
The real question however is not whether the manufacturer of something brand new will meet the advertised specs; it is whether you want to pay $600,000 or so to be an unpaid tester
Not getting 207kt is the least of peoples' problems.
Joined: May 2001
Posts: 4,729
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From: 75N 16E
I recall reading the DA42 would do 207kt
Realistic cruise speed for a DA42 is 155Kts TAS at 70% power (5.9 USG per side).....
Joined: Sep 2007
Posts: 237
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From: Some sunny place with good wine and good sailing
"I sometimes wonder why I didn't buy a TB21 instead. It does do less MPG at low levels (lower engine compression ratio), has about 2x the engine fund (bigger overhaul cost, due to a very rare IO540 variant), but with full TKS it has much more mission capability."
DA42 has TKS as an option. It works very well indeed, better than other TKS systems I have tried.
Others have misquoted perfo of DA42 - in fact you will see TAS155kts at F100 at 70%, burning 4.9USG per side with the latest 2.0 engines.
Finally the practical platform of the DA42 is F180, but yes, they have tested one to F250 (or thereabouts) at which point one of the engines stopped, presumably because the ECU could no longer work out what was going on. It restarted quite happily at lower altitude and there was no permanent damage.
To me the biggest advantage of Diamonds is burning JetA1 - not just because it is cheaper but more importantly because of its very high flashpoint. No Diamond has ever caught fire on crashing (and few have crashed and then due to pilot error). I once had a major fuel leak on a DA40 - on landing at the diversion I took the cowling off and started up and it was spraying very large amounts of JetA1 directly from the common-rail high pressure pump onto the turbocharger. I had flown for an hour or so (across water) to the diversion in that condition.
With most Avgas planes, if you crash or have a fuel leak of that magnitude you are lucky if you don't have a fire.
DA42 has TKS as an option. It works very well indeed, better than other TKS systems I have tried.
Others have misquoted perfo of DA42 - in fact you will see TAS155kts at F100 at 70%, burning 4.9USG per side with the latest 2.0 engines.
Finally the practical platform of the DA42 is F180, but yes, they have tested one to F250 (or thereabouts) at which point one of the engines stopped, presumably because the ECU could no longer work out what was going on. It restarted quite happily at lower altitude and there was no permanent damage.
To me the biggest advantage of Diamonds is burning JetA1 - not just because it is cheaper but more importantly because of its very high flashpoint. No Diamond has ever caught fire on crashing (and few have crashed and then due to pilot error). I once had a major fuel leak on a DA40 - on landing at the diversion I took the cowling off and started up and it was spraying very large amounts of JetA1 directly from the common-rail high pressure pump onto the turbocharger. I had flown for an hour or so (across water) to the diversion in that condition.
With most Avgas planes, if you crash or have a fuel leak of that magnitude you are lucky if you don't have a fire.
Joined: Oct 2006
Posts: 647
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From: Brussels - Twin Comanche PA39 - KA C90B
Like i said before, on paper and from the salespeople it sounds all just fantastic, in reality i know DA40 and DA42 owners who tell me the problems they have, the downtime they encounter, and the !!!!ty service from both Diamond and Thielert.
Somebody smart said once: "Even for a private pilot downtime costs money..."
Somebody smart said once: "Even for a private pilot downtime costs money..."
Joined: Jun 2003
Posts: 13,787
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From: EuroGA.org
they have tested one to F250 (or thereabouts) at which point one of the engines stopped, presumably because the ECU could no longer work out what was going on. It restarted quite happily at lower altitude and there was no permanent damage.
I would be a little concerned about engines simply suddenly stopping due to altitude. One might have to do an emergency climb one day... Still, FL180 is OK for an IFR tourer, just.
On downtime, pilots' attitude varies enormously. Many evidently accept periods of months of no flying.
Joined: Oct 2006
Posts: 647
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From: Brussels - Twin Comanche PA39 - KA C90B
On downtime, pilots' attitude varies enormously. Many evidently accept periods of months of no flying.
I like the old dual magneto system with WWII technology, ok, it's not the new technology of the Thielerts but at least it keeps my engine running when all my electrical systems fail...don't say it doesn't happen, it does, it has happend several times.
I agree that they don't explode that easely but it can explode when crashing, a pluspoint of the Diamonds is that they have a 'real' fuel tank and not a wet wing like the mooney or the cirrus.
Joined: Nov 2006
Posts: 150
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From: Yorkshire
I only have about ten hours on the DA40 but you must be exceptionally unlucky to have so many total systems failures. Remind me not to be in your aeroplane 
How many complete electrical failures / piloting hours do you have sternone?
How many complete electrical failures / piloting hours do you have sternone?
Joined: Sep 2007
Posts: 237
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From: Some sunny place with good wine and good sailing
I was at the Diamond Factory on Easter Monday.
There are both DA42 and a DA40 flying fitted with the new Diamond engines. One of the pilots told me that the DA40 cruised at 170kts at FL120 at 100%. Fuel consumption is 20% less than the Thielert.
The new engine has the turbo mounted higher than on the Thielerts, so there is a change to the engine cowling. I have a photo of the DA42 test plane and can post it if anybody interested.
First deliveries of new engine are expected (by management) in second quarter of 2009 but the engineers are (apparently) not so optimistic.
DA50 is also flying regularly. I have a photo of it fitted with flow indicators on the wings.
Nobody knows exactly why the DA42 MPP crashed in Romania, though it is not reckoned to be technical failure. But survey work is conducted at high weight and low speed (and in this case in a mountainous environment) and the suggestion is that it may have been a handling error.
Anybody interested in the photos send me an email or explain an easy way to post photos on here!
There are both DA42 and a DA40 flying fitted with the new Diamond engines. One of the pilots told me that the DA40 cruised at 170kts at FL120 at 100%. Fuel consumption is 20% less than the Thielert.
The new engine has the turbo mounted higher than on the Thielerts, so there is a change to the engine cowling. I have a photo of the DA42 test plane and can post it if anybody interested.
First deliveries of new engine are expected (by management) in second quarter of 2009 but the engineers are (apparently) not so optimistic.
DA50 is also flying regularly. I have a photo of it fitted with flow indicators on the wings.
Nobody knows exactly why the DA42 MPP crashed in Romania, though it is not reckoned to be technical failure. But survey work is conducted at high weight and low speed (and in this case in a mountainous environment) and the suggestion is that it may have been a handling error.
Anybody interested in the photos send me an email or explain an easy way to post photos on here!
