Advances in DC-3 technology
The DC-3 was fitted with four aluminium
fuel tanks (two main ones and two
auxiliary ones), housed in the central
section of the wings, with a total capacity
of 822 gallons. Each engine was supplied
by a separate circuit with its own pumps
and valves. In addition, the aircraft also
had a couple of manual pumps which
could be operated by the pilot in case
of emergency. The fuel/air ratio of the
mixture which flowed into the cylinders
could also be controlled from the pilot’s
cabin according to the flight phase and
operating conditions. The tanks for the
lubrication system were in the nacelles
of the engines, above the housing
containing the landing gear, while the
radiators for cooling the engine oil were
mounted under the nacelles themselves.
Here, too, the installations for the two
engines were separate and they had a
total capacity of 66.5 gallons.
The production plants
Until the outbreak of the World War II, the
production of American DC-3s remained
concentrated in the Douglas plant at
Clover Field in Santa Monica, California,
where all Douglas aircraft had been built
until then. In the course of time, these
plants expanded in various ways so as
to increase their production capacity. The
growing demand arising from the DC-3
Communication
and radio installation
On the DC-3, the navigator/radio operator sat in a separate
compartment behind the pilot’s cockpit, with the instruments mounted
on the left side of the aircraft looking forwards. The radio installation
consisted of two transmitter-receivers (UHF and VHF), usually one
PTR1751 UHF unit and one of AD120 VHF unit. The aircraft also
had an instrument landing system (ILS), as well as being equipped
with the VOR (VHF Omnidirectional Radio Range) radio navigation
system and fitted with DME (Distance Measuring Equipment). In the
military versions, there was also an IFF (Identification Friend or Foe)
device. Internal communications took place through an interphone
system which linked together the pilot’s cockpit, the navigator/radio
operator’s station and the passenger cabin; the same system was
also installed in the military versions.
The navigator/radio
operator’s compartment was
situated behind the pilot’s
cockpit, on the left side of
the aircraft, behind the pilot.
In addition to the VHF and
UHF transmitter-receivers,
the DC-3 was also equipped
with a series of devices for
navigation, such as ILS, VOR
and DME. On the desk, next
to a clipboard, are a map
and instruments for more
traditional navigation.
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Build Douglas DC
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