WACO UPF Series for Sale — Buy or Sell Iconic American Training Biplanes
The WACO UPF Series — most famously represented by the WACO UPF-7 — stands as one of the most significant American biplane designs of the 1930s and early 1940s. Built by the Waco Aircraft Company of Troy, Ohio, the UPF-7 served as an official Civilian Pilot Training Program (CPTP) trainer during World War II, introducing thousands of student pilots to aviation before they transitioned to military aircraft. Today the UPF series occupies a place of honor in antique aviation, combining historical importance with genuine flying pleasure. On Airplane Trade, buyers and sellers of WACO UPF aircraft connect through a dedicated marketplace built for serious aviation enthusiasts.
Historical Significance: The CPTP Legacy
The Civilian Pilot Training Program, launched by the U.S. government in 1939, sought to dramatically expand the pool of trained aviators in anticipation of potential military needs. WACO responded with the UPF-7, a purpose-built trainer variant that combined docile handling with structural ruggedness. Approximately 600 UPF-7s were delivered to CPTP schools across the United States between 1937 and 1942. Many of the pilots who flew P-40s, P-51s, and B-17s in combat received their first flight instruction in a UPF-7. This wartime connection gives these aircraft extraordinary historical resonance. Surviving airworthy examples are treasured artifacts of American aviation heritage.
The UPF Designation Explained
WACO's model coding system assigned meaning to each character: "U" designated the engine category (125–220 hp radials), "P" indicated the fuselage type, and "F" confirmed the standard three-place open-cockpit biplane configuration. The UPF-7 specifically denoted the seventh iteration of this fuselage design. Production aircraft were typically powered by the Continental W-670 radial engine producing 220 horsepower — giving the aircraft strong climb performance and an excellent power-to-weight ratio ideal for aerobatic and formation training.
Design and Airframe Details
The UPF-7 follows WACO's proven construction philosophy: a welded chrome-molybdenum steel tube fuselage covered with Grade A cotton or linen fabric, married to wood-and-fabric wings with streamlined wire bracing. The equal-span biplane wing arrangement provides excellent lift characteristics at low airspeeds, making the aircraft forgiving for student pilots and ideal for grass strip operations. The tandem cockpit seats two with the student forward and instructor aft, each position having full dual controls. A fixed conventional tailwheel undercarriage with rubber bungee shock absorption provides classic taildragger handling that builds stick-and-rudder fundamentals in new pilots.
Performance Specifications (UPF-7)
- Engine — Continental W-670-6A, 220 hp 7-cylinder radial
- Maximum Speed — 152 mph (245 km/h) at sea level
- Cruise Speed — 128 mph (206 km/h) at 75% power
- Range — 370 miles (595 km) with standard fuel
- Service Ceiling — 16,250 ft (4,953 m)
- Rate of Climb — 1,150 ft/min (351 m/min)
- Gross Weight — 2,650 lbs (1,202 kg)
- Empty Weight — 1,680 lbs (762 kg)
- Wingspan — 30 ft 0 in (9.14 m)
- Length — 22 ft 9 in (6.93 m)
- Seats — 2 (tandem open cockpit)
Flying Characteristics
Pilots who fly the WACO UPF-7 consistently describe it as the quintessential open-cockpit biplane experience. The Continental W-670 radial produces a distinctive seven-cylinder exhaust note that carries across the airfield. The aircraft's forgiving stall characteristics make it approachable for pilots building tailwheel time. The UPF-7 is also a capable aerobatic platform — loops, chandelles, lazy eights, and snap rolls are all within its structural envelope — making it popular for airshow performances and aerobatic proficiency training. Large, sensitive ailerons provide crisp roll response and predictable behavior throughout the entire flight envelope.
Buying a WACO UPF Series: What to Evaluate
Purchasing a WACO UPF Series aircraft requires careful due diligence. Prospective buyers should engage an A&P mechanic with biplane restoration experience to conduct a thorough pre-purchase inspection covering:
- Continental W-670 engine condition — These radials require specialized overhaul shops; verify TBO status and cylinder compression
- Fabric integrity — Test fabric tension using an approved tester; replace if below minimum specification
- Wire bracing — Inspect all flying and landing wires for corrosion, fraying, and proper tension
- Documentation — Complete, continuous logbooks significantly increase value; gaps raise red flags for buyers and insurers
- Restoration quality — Assess paint finish, fabric application, and whether work was performed by experienced craftspeople
- Airworthiness Directives — Verify compliance with all applicable ADs for airframe, engine, and propeller
Collector Value and Market Pricing
Fully restored WACO UPF-7s in flying condition command prices ranging from $65,000 to $140,000 depending on engine hours, restoration quality, cosmetic presentation, and documented history. Aircraft with wartime CPTP documentation, original paint schemes, or airshow histories attract premium valuations from collectors. Unrestored projects in structurally sound condition offer entry points for buyers willing to invest in a restoration, with excellent potential to recover costs in a finished, show-quality aircraft. The UPF-7's WWII heritage ensures lasting collector demand and strong long-term value retention.
List or Find a WACO UPF Series on Airplane Trade
Airplane Trade is the premier destination for buying and selling historic American biplanes including the WACO UPF Series. Whether you are searching for your first antique aircraft or ready to sell a fully restored UPF-7, our marketplace gives you the tools to reach a worldwide audience of qualified aviation buyers. Browse current listings, post detailed specifications and photos of your aircraft, and connect directly with motivated sellers and buyers who share your passion for classic aviation history. Join us today and help preserve the legacy of one of America's greatest training aircraft.