When Waco released its slightly larger custom cabin series, those original Cabin series aircraft it continued to produce were re-designated as ‘Waco Standard Cabin series’, with the final designation letter changing from C to C-S to S. For instance in 1935 the YKC became the YKC-S, then the YKS-6 in 1936. All three were indistinguishable from each other. Waco used numeric suffixes like -7 to indicate a sub-variant introduced in 1937 and so on. The standard cabin can be subdivided again into three groups, early examples having a boat-tail skylight (QDC, OEC & UEC), mid series aircraft with a faired skylight (CJC, UIC, UKC, YKC) or late examples with no skylight (DJC-S, HKS, ZKS, UKC-S UKS-7, VKS-7, YKC-S, YKS-6 & 7, ZKS-6 & 7). All of the types built under the C-S and S designators lacked a skylight though the skylight could be faired over on earlier aircraft. Later types were also slightly longer than earlier models.
Waco ZKS-6
Probably only one DKS-6 was built, in 1936.
From about 1937, all S series aircraft had wings lacking leading and trailing edge cutouts. Externally, the S series differed from the Custom or later C series in continuing with early C series features such as ailerons on both wings, linked by a prominent strut, and square edged rear side windows. Like most Waco aircraft, the S series were available with many different engines (identified by the first letter of the type designation).
The S series proved to be popular with both commercial and private pilots and over 50 were still airworthy in 2001, including examples of the CPTP VKS-7F version. During the Second World War several S series aircraft were impressed by the USAAF as the UC-72K or UC-72M and used as Liaison, executive light transport and instrument refresher training aircraft. Two VKS-7 became UC-72D, one YKS-7 became UC-72K, and two ZKS-7 became UC-72M, in 1942.
1936 Waco YKS-6
The 29 ZKS-6 & 7 built were re-designated from ZKC-S in 1936.
Waco YKS-6
65 YKS-6 built and 21 ZKS-7 1937(ATC 626) built at $5,695, one was converted to HKS-7 (300 HP Lycoming R-680-13 in 1947).
Waco YKS-7 NC19371
One YKS-7 was impressed by the USAAF as UC-72K in 1942 (NC19353) and one to the USN (09784).
Waco HKS-7 NC50662
The HKS-7 and HPF-7 of 1948 were not Waco production, but UKS (HKS-7) and UPF (HPF-7) modified with 300hp Lycomings (hence the “H”) and issued an STC. Two were reported as converted, NC29998 and NC32065, the latter reregistered NC50662.
Waco HPF-7 NC32065
Two of the 1937 UKS-7(ATC 648) were built, NC17721 and a CF- registered example, priced at $5,980.
Waco UKS-7 NC17721
Eighteen 1937 VKS-7 (ATC 648) were built at $5,980, of which two were impressed by USAAF as UC-72D (NC2307 and NC20955. Twenty-one VKS-7F cross-country trainers with controllable-pitch propeller went to the CPTP, with some repowered with 250hp W-670.
Waco VKS-7F NX31658
Six 1934 ZKS/ZKS-6 (ATC 533) were built; NC49, NC14050, NC17456, NC17460, CF-BDK, CF-BBQ, the ZKS-6 appearing in 1936. Redesignated ZKC-S Standard in 1935.
Waco ZKS-6 NC330TC
Eighty-six YKS-7/ZKS-7 were built, of which two ZKS-7 were impressed by the USAAF as UC-72M (NC2628, NC20954) and two as UC-72P (NC20909, NC20950). The 1937 ZKS-7 (ATC 626) was priced at $6,435.
VKS-7 Date: Jun 1937 Engine: Continental W-670M, 240 hp (179 kW) Length OA: 25’3″(7.70m) Span (upper): 33’3″(10.13m) Span (lower): 28’3″(8.61m) Empty weight: 1,917 lb (870 kg) Max gross weight: 3,250 lb (1,474 kg) Maximum load: 1,333 lb (605 kg) Maximum Speed: 149 mph (240 km/h) Cruise speed: 133 mph Stall: 50 mph Range: 530 mi Seats: 4-5 Price: $5,890 18 built
VKS-7 Date: 1938 Engine: Continental W-670M, 240 hp (179 kW) Length OA: 25’3″(7.70m) Span (upper): 33’3″(10.13m) Span (lower): 28’3″(8.61m) Maximum Speed: 145 mph (233 km/h) Empty weight: 1,960 lb (889 kg) Max gross weight: 3,250 lb (1,474 kg) Maximum load: 1,290 lb (585 kg) Price: $7,770 18 built
VKS-7F Date: Jun 1937 Engine: Continental W-670M, 240 hp (179 kW) Length OA: 25’3″(7.70m) Span (upper): 33’3″(10.13m) Span (lower): 28’3″(8.61m) Height: 8 ft 6 in (2.59 m) Wing area: 244 ft2 (22.69 m2) Empty weight: 2,256 lb (1,023 kg) Max gross weight: 3,250 lb (1,474 kg) Maximum load: 994 lb (451 kg) Maximum Speed: 145 mph (233 km/h) Cruise speed: 127 mph (204 km/h) Range: 518 miles (833 km) Service ceiling: 13,000 ft (3,962 m) Rate of climb: 850 ft/min (4.3 m/s) Crew: 1 Capacity: 3 or 4 passengers Price: $12,500 Built for Civilian Pilot Training Program as navigational trainer F designates use of flaps 21 built
YKS-6 Date: 1936 Engine: Jacobs L-4, 225 hp (168 kW) Length OA: 25’4″(7.72m) Span (upper): 33’3″(10.13m) Span (lower): 28’3″(8.61m) Maximum Speed: 144 mph (232 km/h) Empty weight: 1,809 lb (821 kg) Max gross weight: 3,250 lb (1,474 kg) Maximum load: 1,441 lb (654 kg) Price: $4,995
YKS-7 Date: Feb 1937 Engine: Jacobs L-4M/MB, 225 hp (168 kW) Length OA: 25’3″(7.70m) Span (upper): 33’3″(10.13m) Span (lower): 28’3″(8.61m) Empty weight: 1,882 lb (854 kg) Max gross weight: 3,250 lb (1,474 kg) Maximum load: 1,368 lb (621 kg) Maximum Speed: 146 mph (235 km/h) Cruise speed: 130 mph Stall: 50 mph Range: 590 mi Seats: 4-5 Price: $5,695
The 1931 Waco Model C “QDC” four place cabin biplane marked the entry of Waco in the field of cabin aircraft to compete with such established manufacturers as Bellanca and Stinson. The ship was powered with a Continental 165 hp engine and equipped with a metal propeller, cowl ring, electric starter, dual controls, brakes and tail wheel. The control wheel is on a jointed column, so that the ship can be piloted from the right or left, and the rudder pedals are dual.
The QDC was slightly shorter that the UOC and was 500 lb lighter. WACO replaced the QDC in 1933 with its most successful cabin design, the UIC.
The four place ODC of 1931 was priced at $5,885, and was modified to QDC.
Waco ODC NX11250
Two 1931 PDC (ATC 2-388) were specially modified three seat cabin biplanes built on special order.
WACO delivered 83 UICs before replacing the model with the UKC/YKC/CJC series of standard cabin aircraft in 1934. These trendy airplanes became a favourite of aviators like Jacqueline Cochran and corporate magnates such as Henry Dupont.
Forty 1934 UKC (ATC 528) were built selling for $6,285, redesignated UKC-S Standard in 1935, and UKS-6 in 1936.
Waco replaced the QDC in 1933 with its most successful cabin design, the UIC. Powered by a 210-horsepower Continental radial engine, the UIC was a four-person biplane with a conventional fixed tail wheel landing gear. The well-appointed cabin was accessed by automobile-style doors on each side, with a pair of individual front seats and a roomy rear bench seat for another two passengers.
The UIC’s fabric-covered fuselage was constructed from welded steel tubing, shaped with wooden formers and stringers while the wings were fabricated with spruce spars, spruce and wooden ribs, and aluminium edges. Ailerons on both wings were covered in aluminium and connected with push-pull struts that operated them in pairs. The UIC’s stable handling characteristics were considered to be forgiving, with good performance. Delivered with a full set of flight controls and instrumentation, the UIC was priced at a modest $6,000, well within the reach of smaller corporations and airlines.
WACO delivered 83 UICs (ATC 499), including prototype NC13061, selling for $5,985 before replacing the model with the UKC/YKC/CJC series of cabin aircraft in 1934.
More than fifty 1935 YOC at $6,895-7,295, and YOC-1 at $7,995 (ATC 569) were built.
Waco YOC NC15234
One YOC-1 was impressed by the USAAF as UC-72N (NC14683 or NC15248). South African Air Force impressed at least ten Wacos of different types (CUC and YOC).
Four 1935 UOC (ATC 568) were built, priced at $6,850-7,375. Two civil UOC were NC500/NC303E and NX14631.
Waco UOC ZK-ALA
The Royal New Zealand Air Force impressed one UOC (ZK-AEL/AEA). The Argentine Navy operated EQC-6 and one UOC.
The Waco ‘F’ series of biplanes supplanted and then replaced the earlier ‘O’ series of 1927/33. The ‘F’ series had an airframe which was smaller and about 450 pounds (200 kg) lighter than the ‘O’ series, while continuing to provide accommodation for three persons in tandem open cockpits. A similar performance to the earlier model was obtained on the power of smaller and more economical engines.
The initial models were the INF (125 hp / 93 kW Kinner engine) with around 50 built, KNF (100 hp / 75 kW Kinner, about 20 built, ATC 313, at $3,630) and the RNF (110 hp / 82 kW Warner Scarab, nearly 150 built), all of which had externally braced tailwheel undercarriages. Many further sub-models followed with more powerful engines of up to 225 hp / 168 kW. The most powerful in the range was the ZPF of 1936/37, intended for executive use.
Waco KNF NX653N
Only four 1931 MNF’s (ATC 393) were built; NC11213, NC11222, NC11239 and NC11246, priced at $4,475.
MNF
Al Menasco used the MNF to help promote his engines. A Heywood air-operated starter, caster action tail wheel, compass, navigation lights, first-aid kit and fire extinguisher were standard equipment on the MNF. NC11213 has the optional, Hamilton Standard ground adjustable prop. Brakes were optional.
The first QCF was finished on May 12, 1931. Thirty-one were built in 1932.
QCF-2
The ‘F’ series was popular with private owner pilots for sporting and other uses and continued in production through the late 1930s. The tandem cockpit UPF-7 was adopted by the Civilian Pilot Training Program and continued in production until 1942 by which time over 600 had been built.
One EPF-6 was built in 1936 and test-flown.
The 1936 VPF-6 was similar to the VPF-7 but with narrower landing gear and smaller wing cut-out. It was advertised as available, but none was produced. The 1937 VPF-7 (ATC 642) was the export version of the UPF-7. Priced at $9,500, six went to Guatemala, all of which returned to the US in 1959.
Waco VPF-7 NC78435
Waco XJW-1 9522
Two, 9521/9522, XJW-1 of 1934 were a USN version of the UBF as hook-up trainer and mail shuttle for the dirigible Macon.
Waco XJW-1 9522
In 1937 Waco introduced its Model UPF-7 as an open-cockpit biplane with a 164-kW (220-hp) Continental W-670-K radial engine and seating for two or three. The type was intended for training and sport use. A single example was evaluated by the USAAC as a primary trainer during 1939 with the designation XPT-14.
Waco XPT-14 39-702
The 1939 XPT-14 39-702 crashed in testing on 11 October 1939.
Then followed 13 YPT-14 service trials aircraft, which were later re-designated PT-14.
Waco YPT-14
A single civil 1937 Model UPF-7 (ATC 642) was impressed in 1941 with the designation PT-14A. However, another 600 aircraft of the same basic type were ordered, priced at $9,500, with three engine types for the Civilian Pilot Training Program that undertook pilot training at educational institutions to provide a pool of trained pilots in the event of war. Another 31 similar aircraft were bought by the Civil Aeronautics Authority for its own flying unit, and 14 to the USAAF as YPT-14.
Waco UPF-7 1941
One QNF model was built. It flew, but presented nose-heaviness problems.
The three place YPF-6 and YPF-7 OF 1935 (ATC 586) featured a sliding canopy and unit price of $8,395. Five were built as YPF-6 (NC15700, NC15606, NC15711, NC16579, NC17470) and three re-designated in 1937 as YPF-7 (NC17710, NC17715, NC20907).
Waco YPF-6 NC16579
Waco YPF-7
Three ZPF-6 (ATC 586) were built in 1936, NC15707, NC16579, and NC17470, featuring a sliding canopy. The price was $7,385.
Two ZPF-7 were built in 1938, NC17710 and NC17715.
Waco ZPF-7 N29962
Approximately 600 came out of the Troy, Ohio factory between 1937 and 1942.
The WACO Aircraft Company of Ohio Inc had built three replicas by December 2011, which they designated MF.
Military operators
The Guatemalan Air Force received at least 1 Waco YMF-7 in 1934, which was still in airworthy condition in 1998.
The United States Army Air Corps adopted the UPF-7 as the PT-14, with one XPT-14 and 13 YPT-14s being purchased, with an additional UPF-7 impressed in 1942 as a PT-14A. Some were operated by the United States Navy.
PT-14
Waco CPF of Brazilian navy
The 1932 PBF (ATC 491) was priced at $4,415. Basically the same as PCF with modified ‘B’ wings. Four were built; NC13029, NC13049, NC13428, and NC13446.
Waco PBF NC13029
Three 1931 PCF (ATC 453) were built; NC11476, NC11483, and NS12439, priced at $4,415. The PCF-2 (Certified ATC#473 2 October 1931) featured a new cross-braced undercarriage.
Waco PCF NS12439
177 1930 Waco RNF were built (ATC 311, and 2-255 and 2-311) for weight changes. They were priced at $4,195-4,320, or $4,450 with an optional 125hp Warner engine.
Waco RNF NC853V
Waco UBF NC155Y
Priced at $5,025, about 11 1932 Waco UBF and UBF-2 (ATC 473) were built, of which 2 went to the USN as XJW-1 dirigible “skyhooks”, and one was fitted with EDO floats in 1933; NC13074.
Waco UBF-2 NC13419
Eighteen of the 1934 UMF-3 and -5 (ATC 546) were built at $6,530, of which 4 went to Guatemala, and 3 to the Cuban Navy. They were the forerunner of the UPF-7.
Waco UMF-3 NC14041
The YMF-3 (ATC 542) of 1934 was powered by a 225hp Jacobs L-4. Powered by a 245hp Jacobs L-4, the YMF-5 appeared in 1935 for $6,795. Eighteen were built.
The design was revived around.1990 by Classic Aircraft Corp of Lansing MI as the YMF-5 Super.
Waco YMF-5 NC14067
Considerable numbers of ‘F’ series biplanes, both original and newly built, remained in service in mid-2009.
INF Certified ATC#345 2 August 1930 Engine: Kinner B-5, 125 hp (93 kW) Span: 29 ft 7 in (9.1 m) Length: 20 ft 10 in (7 m) Height: 8 ft 5 in (2.5 m) Wing area: 244 sq ft (22.7 sq m) Empty weight: 1870 lb (848 kg) Loaded weight: 2650 lb (1202 kg) Maximum speed: 128 mph (206 km/h) Cruise speed: 96 mph Stall: 40 mph Range: 370 mi Seats: 3 Price: $4,110 50 built
KNF Certified ATC#313 12 April 1930 Engine: Kinner K-5, 100 hp (75 kW) Wingspan: 29’7″ Length: 21’4″ Useful load: 776 lb Max speed: 100 mph Cruise speed: 85 mph Stall: 40 mph Range: 430 mi Seats: 3 20 built
PCF Engine: Jacobs LA-1, 170 hp (127 kW) Wingspan: 29’7″ Length: 20’10” Useful load: 972 lb Max speed: 119 mph Cruise speed: 101 mph Stall: 42 mph Range: 430 mi Seats: 3 3 built
PCF-2 Certified ATC#473 2 October 1931 Engine: Jacobs LA-1, 170 hp (127 kW) new cross-braced undercarriage
QCF QCF-2 Certified ATC#416 9 April 1931 Engine: Continental A70, 165 hp (123 kW) Wingspan: 29’7″ Length: 20’4″ Useful load: 864 lb Top speed: 125 mph Cruise: 108mph Stall: 45 mph Range: 430 mi Seats: 3 31 built Prototype NC11241
UBF / UBF-2 / XJW-1 Engine: Continental R-670, 210 hp (157 kW) Wingspan: 29’6″ Length: 20’9″ Useful load: 920 lb Max speed: 132 mph Cruise speed: 116 mph Stall: 42 mph Range: 400 mi Seats: 3 Two UBF designated XJW-1 were used by the US Navy as hook-up trainers for the Curtiss F9C Sparrowhawk airship-borne fighters. Around 11 built
1932 UBF
UMF / UMF-3 / UMF-5 Engine: Continental R-670A, 210 hp (157 kW) Wingspan: 30’0″ Length: 23’2″ Useful load: 1015 lb Max speed: 143 mph Cruise: 128 mph Stall: 47 mph Range: 460 mi Seats: 3 longer wider fuselage and larger vertical fin 18 built
Waco UPF-6 Engine: Continental R-670, 210 hp (157 kW) Seats: 2-3 Prototype for UPF-7
UPF-7 / PT-14 tandem training version with wider-track undercarriage (USAAC) Engine: l x Continental R-670-3 or W-670-6A, 164kW (220 hp) or Continental R-670-6, 220 hp Wingspan: 30 ft 0 in (9.14 m) Wing area: 244 sq.ft (22.67 sq.m) Length: 23 ft 1 in (7.04 m) Height: 8 ft 5 in (2.57 m) Max TO weight: 2,650 lb (1202.02 kg) Empty weight: 1,870 lb (848.22 kg) Maximum speed: 128 mph (207 km/h) Cruise speed: 114 mph (185 km/h) Stall: 50 mph Range: 400 miles (644 km) Service ceiling: 14,800 ft (4,511 m) Armament: none Seats: 2-3 14 became YPT-14 trainers 40-014 – 40-026 over 600 built
All Aero 