Cessna 170B

Cessna introduced the 170 in 1948 as a four-seat, conventional-gear airplane to replace the two-seat 140. The original 170 had a Continental C-145 engine (the predecessor designation to the O-300) and a metal wing with internal fabric. The 170A in 1949 introduced an all-metal wing. The 170B in 1952 added split flaps, a slightly larger wing area, and the more refined fuselage that would carry over directly to the 172.

Production ran through 1956 when Cessna replaced the 170B with the 172. The 172 was essentially a 170B with a nosewheel and minor revisions. The 170 line ended after about 5,000 total aircraft. The 172 went on to become the best-selling general aviation airplane in history with over 44,000 produced. The 170 fleet has remained popular with vintage-aircraft enthusiasts, backcountry pilots, and float operators throughout the decades.

Most flying 170s today are 170Bs (1952-1956 production). The split-flap wing and refined fuselage make the B variant more capable and more popular than the earlier 170 and 170A. The International Cessna 170 Association is the dedicated type club. The fleet that survives has been maintained by owners who care, and many 170s have had extensive restoration work over the years. Original-condition airplanes are now rare. Most have been re-covered, re-painted, re-upholstered, and modernized in various ways while retaining the type-certificate airframe.

The Cessna 170B cruises at about 105 KTAS at 75% power, burning 7.5 gph of 100LL. At long-range cruise (65%), the airplane drops to about 95 KTAS on 6.5 gph. Performance is roughly comparable to the early 172 (with the C-145 / O-300 engine), but the taildragger gear adds a few knots of cruise speed due to reduced parasite drag versus the tricycle 172.

Useful load is about 950 pounds. Full fuel (37 gallons usable) leaves about 730 pounds for people and bags. That's four adults of typical weight plus light luggage, or two adults plus camping gear for backcountry trips. The 170 was designed for utility and the cabin shows it. Range with reserves is about 500 nm. Service ceiling is 14,000 ft on paper but the 145 hp Continental gets thin above 8,000 to 10,000 ft DA in practice.

The Continental O-300-A (originally designated C-145) is the engine on the 170B. It's a six-cylinder, horizontally opposed, direct-drive piston rated at 145 hp at 2,700 RPM. Continental's published TBO is 1,800 hours per Continental Service Information Letter SIL 98-9E. The O-300 has a longer fleet history than most engines flying today, but Continental has not produced new O-300s in decades. Parts availability is reasonable but tightening over time.

Field overhauls at Continental-experienced shops run $35,000 to $48,000 in 2026 prices. Cylinder availability is the main constraint. Continental no longer manufactures new O-300 cylinders, so overhauls typically reuse existing cylinders or source from limited overhaul-cylinder stock. Some 170 owners have converted to the four-cylinder O-300 derivative the Continental O-360 (also out of production), or to other engines via STC. STC conversion paths to Lycoming O-320, O-360, or Continental O-470 exist and offer different trade-offs in cost, performance, and parts availability.

Oil consumption on a healthy O-300 runs about 0.2 to 0.4 quarts per hour. The six-cylinder Continental is heavier than the four-cylinder Lycomings that replaced it on later Cessnas, which contributes to the 170's nose-heavy feel relative to a 172. Many 170 owners run the engine on-condition past TBO, which is legal under Part 91 non-commercial operation when supported by oil analysis and compression checks.

Plan on $130 to $180 per flight hour at 75 hours a year of utilization, all-in. The 170B's operating economics are between the Cessna 150 and the 172. Fuel and oil run about $45 to $60 per hour at 7.5 gph and $5.50 to $7 for 100LL. Engine overhaul reserve is $19 to $27 per hour based on a $35,000 to $48,000 overhaul amortized across the 1,800-hour TBO. Airframe maintenance reserve is $15 to $25 per hour, higher than a 152 because of the vintage airframe, fabric inspection where applicable, and tailwheel-specific items.

Annual fixed costs (hangar, insurance, annual inspection) add another $45 to $80 per hour at 75 hours a year of utilization. Tailwheel insurance is meaningfully more expensive than tricycle insurance. Pilots without recent tailwheel time typically pay $2,500 to $5,000 a year for hull coverage, dropping to $1,500 to $3,000 after gaining 50+ hours in type. Insurance underwriters look hard at tailwheel currency and proficiency.

Acquisition cost in mid-2026: Original 170 (no suffix) aircraft trade $50,000 to $90,000 depending on condition. 170A aircraft run $60,000 to $100,000. 170B aircraft run $70,000 to $130,000. Float-equipped, ski-equipped, or backcountry-modified 170s command premiums of $15,000 to $40,000 over land-only equivalents. STC-converted aircraft with non-original engines vary widely depending on the conversion specifics.

International Cessna 170 Association is essential. Annual dues run about $50. Members get the forum, technical articles, type-specific pre-buy guidance, and the accumulated 70 years of fleet experience. Most parts questions, restoration questions, and overhaul-shop recommendations route through the Association.