the Theilert and Diamond are turbocharged and make full power up to (I think) 10,000 ft or so. thus when compared to a naturally aspirated gasoline engine their performance stays constant and then is better as you get hotter and higher.

Which is sort of useless as this type of plane spends most of it's life well below 8000 feet.

So the diesel is still starting out with 15 percent less power, and it weighs 96 pounds more. There's no getting around that.

Wouldn't that be illegal in the US? The CD-155 TCDS and online documentation specifies diesel fuel that meets EN 590, a European specification. It doesn't appear that US #2 diesel meets the EN 590 spec. Is EN 590 diesel even available in the US?

Wouldn't that be illegal in the US? The CD-155 TCDS and online documentation specifies diesel fuel that meets EN 590, a European specification. It doesn't appear that US #2 diesel meets the EN 590 spec. Is EN 590 diesel even available in the US?

In California road diesel is more than jet fuel at most airports

Does it? or maybe if it wasn't for the fact that normally aspirated engine looses so much performance up there people would fly higher?

I for one climb laways as high as it makes practical sense, I'll fly at 7-8k on trips <200miles, I bet in diesel I would fly higher on average, because it would be easier to get up there.

Fuel specs can get tricky sometimes.

Per customer request we approved use of Artic Diesel in a turboprop even though there were some significant low temperature restrictions.

Another customer requested use of JP-1. We did a lot of digging and couldn't come up with the specification for what they were using. In the U.S., JP-1 was a kerosene type fuel with better low temperature properties and became obsolete back in the stone age, with the specification no longer available. We ended up approving it per management direction. Our belief was that JET A or A-1 is sometimes called JP-1 in some countries.

Diesel engines can be even trickier since the engine limitations usually state a cetane number requirement, which is not a specification property for jet fuels. I don't know what the workaround is.

As one flight test engineer said, it is all just dead dinosaurs anyway.

Does it? or maybe if it wasn't for the fact that normally aspirated engine looses so much performance up there people would fly higher?

I for one climb laways as high as it makes practical sense, I'll fly at 7-8k on trips <200miles, I bet in diesel I would fly higher on average, because it would be easier to get up there.

No one has talked about the Deltahawk engine at 180hp. It will be interesting to see what that engine does in comparison to the Lycoming version......and theres a 235hp version comming soon.

I hung the original Deltahawk engine on their Cirrus SR20 test bed back in 2013. Since then, they've continued to refine the engine. I think that this will be the first diesel to make bigger inroads in the retrofit market. It has the performance needed, and the right weight, to compete with avgas engines. The only question will be the economics.

Call Blueline Aviation at Jonhnston Regional KJNX.

They have a fleet of over 30 Diesel DA40s and some DA42 in active flight school.

Lots of defects and electronic problems with a few engine shutdown accidents from what I have seen and heard passing through. Bolts wearing through engine cases is one example. Large part of the fleet grounded for repairs of what should have been a mature design.
Looks to be a nightmare with a fleet purchase of sequential serial numbers so each defect may affect them all.

The design has been a problem from the start going way back to the Thielert engine. Proceed with caution. No morals in this business especially from Europe.

On the ground I did hear that they had a couple 172s with Lycomings for spin training. They just ran and ran with no problems.

https://www.federalregister.gov/documen ... ng-engines

Makes me wonder why a defect for Crankshaft bearing studs known in 2021 was still not complied with on all engines and needed a new AD in 2023?

Seems to be a critical for flight safety item? Why the delay they should have been able to quickly find where the engines are and identify them.

This is the problem. It's a Continental branded engine but not a Continental engine. Who runs the show?

As a side note read item #3 under the AD " Regulatory Findings". What in the world is that statement doing in an Airworthiness directive for defective crankshaft studs?

If the studs fail who cares if the AD would have affected economic impact. The studs don't care if they release the crankshaft from the engine but it would surely affect the occupants at the time. I thought the purpose of the AD system was to provide notice about these types of problems to fix them before a failure caused more accidents. The Economics of something like keeping the crankshaft in the engine are not relevant at that point. Especially if it is a manufacture defect.

For a flight school that operates their airplanes 60-80hrs per month yes I would think it does have a big impact. But the alternative is not good either.

Also wondering about field mechanic replacement of these parts??

I have a friend who was, at one time, a Diamond service center. He literally won't touch them now, too big of a PITA to deal with for warranty work, and they needed quite a bit.

Lots of different factors for picking cruise altitudes. In a low powered plane like an archer, the time to climb can be pretty significant. Winds can be strong at altitude - so depending on which way you are going, you may want to stay low, or as high as you can go. A lot of pilots (including me) like to use O2 above 10K, so I prefer to stay below that unless there is a good reason to go higher.

The option to fly higher is certainly an advantage, but needs to be compared with the lower power at low altitude, and lower useful load.

OTOH, burning Jet-A is a big win. OTOOH, the higher purchase cost or a standard 100LL burning engine will buy a lot of hours of fuel.

Diesel is a reasonable option in some cases, but so far diesel aircraft sales have not done very well in the US, which presumably means most pilots decided they were not a good option for them.



Does it? or maybe if it wasn't for the fact that normally aspirated engine looses so much performance up there people would fly higher?

I for one climb laways as high as it makes practical sense, I'll fly at 7-8k on trips <200miles, I bet in diesel I would fly higher on average, because it would be easier to get up there.

Run far and fast...Airplanes are a poor application for diesel engines. Their power to weight is bad, they require HPDI, and right now, they are impossible to overhaul at traditional shops, so you just throw them away.

Diesels are not the way of the future. EFI on traditional air cooled gas motors is....