--there's a g1 NA SR22 in our club that I fly as my "go-to" and it's been to Lake Tahoe (6,264 elev) and Big Bear (6,752 elev) many times, including the sweltering hot summer months. Many departures where right near the max performance limits of the plane's envelope and it performed exactly as advertised in the POH. Personally, if you plan right it's generally a non-event. Never had any "yikes" moments.. climb rate was still generally decent, again, exactly as the POH said it would be. For these though I do a full power run up to get the mixture set right (NA).
Yup. Look at the book, see if the plane will do what you want. I've flown a normally aspirated 182 out of Leadville KLXV at a density altitude of 12,200 feet on the ground. Takeoff roll was about 2000 feet, but the runway is much longer than that because they want visitors with skinny wings too.
The biggest thing I miss with an NA plane, and why if (err, when) I buy it will be turbo is that I max out on altitude around 10-11K.. the SR22 will go higher, but there's no real speed advantage.. the sweet spot seems to be that 8K-10K neighborhood. It sort of just feels like "wasted displacement" to have this nearly 10 liter engine up there that's barely coughing out 60% power at those altitudes. There's nobody up at 16K-17K and the air tends to be much smoother.. crossing the rockies at 17K is basically a non event. And given the altitude constraint you do have to plan your routes a bit more carefully around the mountains and be more vigilant of the winds
8-10K is pretty much the sweet spot for any normally aspirated plane. Just looking at the amount of oxygen available, with all other engine parameters full you are looking at 75% a little above 7000 feet and 65% at around 11,000 feet. So, if you pull the prop back and run at something other than best power mixture, it's easy to get the 65% most of us like to run our engines at in that 8-10K range.
I have a Mooney M20R Ovation with a 280hp IO-550. It's the same engine as the NA SR22, but the prop maxes out at 2500 RPM instead of 2700 which limits the power to 280hp instead of the 310 on the Cirrus. I'll run it at 65%, WOT, LOP most of the time, and burn about 12 gph in cruise. My cruise speeds go faster up to about 9-10K, where I can do 175 KTAS on that 12 gph. As I climb higher, I'll go slower but also burn less fuel. My favorite example is a leg I flew from Santa Fe, NM back to WI - KSAF TAFOY2.FTI V263 TBE KOVC - 879nm in 4:37, burning a total of 53 gallons of 100LL, truing out at 172 KTAS on 10.1 gph. (Yes, I averaged a 20-knot tailwind as well.)
For climb, you can get a turbo, or just get a plane with a ridiculous amount of horsepower already. I plan on getting to 10,000 in 10 minutes or less, and IME I still see 500 fpm up to 15,000.
There have definitely been times where I've wanted a turbo. But, I've done some math and found that it would not make any sense for me at all. It takes me about 8 nm per 1000 feet just for the climb and descent (2 on the way up, 6 on the way down). Best use of time and fuel is usually to have at least half the flight be in cruise, so that means I need at least 16nm of distance traveled per 1000 feet of climb. The normally aspirated bird is faster than the turbo below about 10K (unless you're one of those "I didn't buy this airplane to go slow" types who flogs your engine). So, that means that anything under 160nm, the NA bird is going to be slightly faster. It's also going to be a lot more efficient - If I had a turbo I'd be burning more like 17 gph.
To gain a significant speed advantage, I would need to be flying legs long enough to justify a climb to FL200. That's 320nm legs. Yes, I do those, but while I take a handful of long-distance trips in the plane per year during normal times, I also like to fly shorter distances a lot - Going to visit my parents is about 60nm, going for $100 burgers I'm not going to go 300 miles, visiting various other recreational pursuits same thing. So, if I had a turbo, it would help me out a few times a year, but I would have higher operating costs (more fuel, more maintenance, more expensive and likely earlier engine overhaul). The way I fly, it would cost me several thousand dollars a year and save me a couple of hours.
In addition, now that I'm flying whiny birds for work, I'm even more glad I don't have a turbo. The flight levels are BORING for the most part. It's not nearly as enjoyable to fly up there. And if I were in an unpressurized plane on oxygen - Well, I use O2 sometimes as it is, if I need to go high for operational reasons (my ceiling is FL200, I've had the bird to FL190 for OROCA due to terrain and I go up high to cross the Great Lakes) I end up on O2 and after a little while it makes my sinuses BURN because it's completely dry air. 0% humidity. Not fun.
@Tantalum knocked it out of the park with his response.
Agreed.
No one complains of having too much power.....get the turbo.
But all kinds of people complain about burning too much fuel... Don't just get the turbo, do the math for your missions and see how much it'll actually help you and what it'll cost you.
