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.[1]
The initial models were the INF (125 hp (93 kW) Kinner engine), KNF (100 hp (75 kW) Kinner) and the RNF (110 hp (82 kW) Warner Scarab), 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.
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.[2]
The 1934 model YMF was substantially redesigned with a longer and wider fuselage, larger rudder and other structural changes, and put into production in March 1986 by WACO Classic AircraftofLansing, Michigan as the YMF-5.[1] Over 150 YMF-5s were completed as of 2017 with new examples being built to specific orders.[3][failed verification]
The WACO Aircraft Company of Ohio Inc had built three replicas by December 2011, which they designated MF.[4]
Considerable numbers of 'F' series biplanes, both original and newly built, remain in service.
Listed in approximate chronological order (per Simpson, 2001, p. 573)
First letter of designation refers to engine installed.
From 1936 Waco added year suffixes to designations—e.g. YPF-6, YPF-7, with the numeral being the last digit of the model year.
INF
125 hp (93 kW) Kinner B-5, certified ATC# 345 on 2 August 1930.
KNF
100 hp (75 kW) Kinner K-5, certified ATC# 313 on 12 April 1930.
RNF
110 hp (82 kW) Warner Scarab, certified ATC# 311 on 7 April 1930.[5]
PCF
170 hp (130 kW) Jacobs LA-1 and new cross-braced undercarriage, PCF-2 certified ATC# 473 on 2 October 1931
PBF
asPCF with 'B' wings
QCF
165 hp (123 kW) Continental A70, QCF-2 certified ATC# 416 on 9 April 1931
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.[10]
Guatemala
United States
Media related to Waco F Series at Wikimedia Commons
