Reason 4 – Turbocharged Cirrus

How much climb time does your normally aspirated single-engine piston require to reach cruise flight?  My Piper Archer took more than 18 minutes to reach 8,000 feet, a typical cross-country altitude, which was usually between 6,000 – 9,000 feet.

Normally aspirated piston engines have a longer climb hang-time than their turbocharged brethren. The turbocharged Cirrus SR22TN will expedite en route climbs for faster cross-country flights.

Reason 4 – Time in Climb Performance

The Cirrus SR22TN Turbo can reach a cruise altitude of 16,000 feet in under 14 minutes using less than 8 gallons of gas, which beats the Piper Archer to 8,000 feet, but here’s “the rest of the story.”

1) Time in Climb Comparison Example

Cirrus SR22TN 16,000 ft ~13.33 minutes ~7.78 gallons used
Piper Archer 8,000 ft ~18.10 minutes ~4.53 gallons used

For years, I flew a Piper Archer between Houston, Texas and Birmingham, Alabama which is a 500 NM trip  (add: Air Traffic Control vectors). In an Archer you’ll need at least 5 hours of flight time with a fuel stop about mid-way.

Because of the fuel stop, the Archer must have a second en route climb to cruise, and now the real time-in-climb comparison becomes clearer. The Archer spends more than 36 minutes with two en route climbs and consumes a greater amount of fuel in the process.

2) Time in Climb Comparison Example

Cirrus SR22TN 16,000 ft ~13.33 minutes ~7.78 gallons used
Piper Archer 2 x 8,000 ft ~36.20 minutes ~9.06 gallons used

The Piper Archer climb is sluggish with slow forward progress, and it seems to take forever to reach cruise altitude. Many times I’d shallow the climb to improve engine cooling and forward speed, even though that extended time in climb further.

With piston engines, time in climb affects a pilot’s choice of altitude.  Normally aspirated planes breed a lower routine range of cruise altitudes best suited for the engine, and not so much weather considerations.

Turbocharged planes offer more altitude options for improved safety and comfort of flight. Altitude changes in a well designed turbocharged plane are efficient and help cut time in flight. Benefits normally aspirated planes cannot easily match.

The turbocharged Cirrus SR22TN, can quickly climb to 16,000 feet and carry out the same 500 nm trip non-stop, in as little as 2 hours & 40 minutes, with 75% power.

Future posts will compares the normally aspirated Cirrus SR22 to the turbocharged SR22TN.

Appendix

Piper Archer II, PA28-181, Lycoming 180 hp, Example Max Power Climb

TAS VS Altitude Minutes Gallons Used Climb GPH
76.00 500 2,000 4.00 1.00 15
76.00 475 4,000 4.21 1.05 15
76.00 420 6,000 4.76 1.19 15
76.00 390 8,000 5.13 1.28 15
Summary 446 8,000 18.10 4.53 15

Cirrus SR22TN Turbo, Continental IO-550-N, Example Max Power (ROP) Climb

TAS VS Climb Feet Minutes Gallons Used GPH
100 1,500 8,000 5.33 3.11 35
120 1,000 8,000 8.00 4.67 35
Cruise Altitude 16,000 13.33 7.78

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