A Third (And Last) Tri-motor
By John Dorcey
I consider myself to be pretty well heeled in aviation history
and while I freely admit that I am not aware of every aircraft ever
made, this one was a real surprise… and a real find. The
Kreutzer Model K-5, 'Air Coach' is today's Plane of the Day. Never
heard of Kreutzer before? Good, that makes at least two of us.
As an overview there were 47 different tri-motor aircraft models
built by 24 various manufacturers during the design's heyday during
the 1920s and 1930s. Of course, that discounts the relatively more
modern Boeing 727, Lockheed's L1011 and the Douglas DC-10/11 and
other modern examples of the tri-engine design.
The Joseph Kreutzer Corporation, located in Venice (CA) built
its first model, the K-1, in 1928. The design termed a 'light
transport' was planned to fill the void between the typical two
seat aircraft and the large airliner of the day with 10 seats or
more. This model had four seats, the ultimate goal was six, and was
powered by three Velie 55-horsepower (HP) engines.
That airframe was then modified to the six-seat Model K-2. This
model was powered by a single 90 HP, LaBlond 7-cylinder engine in
the nose and two 60 HP LaBlond 5-cylinder engines on the wings. The
K-2 was certified as NX-612. The K-3 model featured three LaBlond
90 HP engines, significantly improving performance. The K-2 and K-3
were certificated in the summer of 1929.
The 'Air Coach' was an outgrowth of the K-3, in fact this
airframe was the same one used in all models K-1, K-2, K-3, and
finally modified to a K-5. The K-5 design was approved in September
1929 and featured 3 Kinner K-5 engines of 100 HP.
A planned model using Warner 'Scarab' engines of 110 HP never
left the drawing board. The Kreutzer Corporation built a total of
14 aircraft - 6 K-2s, 2 K-3s, and 6 K-5s. By 1930, like many early
aircraft manufacturers, struggling under the effects of the
depression closed its doors.
This aircraft NC612 was purchased by its third owner, Navajo
Airways, and was based in Winslow (AZ). Navajo acted as a feeder to
Transcontinental and Western Air. Its next owner, Willard Hellman,
would convert the aircraft to model K-5 by upgrading the engines to
the Kinner model.
The Kreutzer K-5 'Air Coach' held Aircraft Type Certificate
(ATC) 223, and according to that document the aircraft has a cruise
speed of 130 mph, landing speed of 45 mph. The service ceiling was
a mountain scaling 17,000 feet with a range of 520 miles. The 1929
price, FOB Venice, was $18,500. Today's price is higher.
NC-612A is owned by Greg Herrick and is the only remaining
example of a Kreutzer aircraft. The airplane, as one might expect,
is immaculate; having undergone an extensive and exhaustive
restoration.