How high can popular turbo SEPs actually go?
I realise that on most turbo plates the ceiling in the POH is mandatory (not sure why) so I am not expecting anyone to say they actually did it 
TB21?
SR22T?
Any turbo Mooney?
Cessna 400/TTX?
Cessna 421C?
DA40?
DA42?
A PA46 comfortably to Fl250. I think the discussed view ceiling as 50fpm is silly. That is essentially not climbing. It is hardly a usable altitude.
The Aerostar Superstar 700 with the 5.5psi modification will march right up to FL280, no problem. If RSVM space wasn’t there, it would probably get to FL300-320 quite easily. Even the lower powered ones like the one I had would get up to FL250. I had mine at FL230 once or twice and it would still climb there.
I think the discussed view ceiling as 50fpm is silly. That is essentially not climbing. It is hardly a usable altitude.
For SEPs, the ceiling tends to be defined at what reduces the rate of climb to 50 or 100fpm (not sure which certification authority uses which).
There is no suggestion that such a ceiling is useful in practice, but that wasn’t my question. One pilot could argue that once the ROC is down to 500fpm then you are finished. Another pilot could argue that 100fpm is usable, especially if crossing some wx which is 100nm ahead and right now you are in VMC, and FL190 can be achieved in 40 mins.
DA42 Austro diesel has a ceiling of FL180 allegedly due to potential turbo issues. Below a certain pressure the turbo may overspeed and disintegrate. It still climbs pretty damn good at that altitude.
The DA40 diesel has a similar ceiling but it depends on model (from memory). The turbo critical altitude is different between models. One would need to take a look at the performance table to see what climb rate can be achieved at the ceiling.
Wrt DA40-180 I would say the practical ceiling is around FL130 where I guess you would see 100-200 fpm
The SR22T and Columbia 400 have same engine and both have a ceiling of FL250. According to book the Columbia 400 climbs to FL250 in 19 minutes and will still climb at 900 fpm at that altitude. Of course you would not want to do that if you care about your cylinders.
The Stemme S10VT has a service ceiling of 30k ft. In another forum someone claimed he’d been at 31k feet with his Cessna T182T.
Yes, most turbos have a maximum operating limit which is a hard certification limit while most NA piston planes don’t as their ponies become weak eventually.
Sometimes this was done to not have to do too much testing and verification. Sometimes it was done for marketing reasons. The T182T is limited to 20k feet which is the same as the earlier TR182 with the same engine power. The TR182 got the 20k limit rather late (it was flight tested up to 24k) in order to not cannibalize sales of the more expensive T210. That was written down in a book by the test pilot of the aircraft. My TR182 climbs at > 600ft FPM at its service ceiling and even at FL250 the climb rate is still good without cooling problems.
The TBM has a certification limit of 31k but I know pilots that routinely fly it at 33k. One even posted a cockpit photo in his for sale ad with the altimeter showing FL330 
Peter wrote:
The other downside is that you will be changing cylinders well before TBO
This is a well distributed myth which I believed too until I came across two independently running GB’s in Mooneys 231 which both reached TBO without new cylinders. The GB engine as opposed to the LB and the later Bravo engine was “known” for overheat and for massive cylinder changes up to twice to TBO. It appears however that a lot of this is because people don’t take care or as usual in aviation widely exagarated.
Operating a turbo engine vs a normally aspirated one needs more care and needs proper instruction and not only a 2 hour type conversion (for the first turbo). A turbo engine can be ruined very fast and very easily whereas normally aspirated ones are usually dead easy to operate, even though many muck up even that by not leaning properly for example. Turbos have in many cases their bad reputation because of pilots who simply don’t know how to operate them.
achimha wrote:
My TR182 climbs at > 600ft FPM at its service ceiling and even at FL250 the climb rate is still good without cooling problems.
I have seen 500 FPM at FL220 in my T182T with two POB and a lot of fuel and luggage. This altitude is often not high enough to overfly the weather but helps a lot.
europaxs wrote:
In another forum someone claimed he’d been at 31k feet with his Cessna T182T.
This is of great interest to me. Could you please give the link?
highflyer wrote:
I have seen 500 FPM at FL220 in my T182T with two POB and a lot of fuel and luggage.
Keep in mind that you are exceeding a certification limit. ATC can see the type of aircraft and theoretically know that it’s an exceedance of the type certificate. It’s easy to prove and you might have to defend yourself although I don’t know of a single case. I would always do it when the alternative is something like flying into IMC that is not trustworthy but on the T182T it’s a clear violation of a certification limit.
