Path: news.nzbot.com!not-for-mail
From: Miloch <Miloch_member@newsguy.com>
Newsgroups: alt.binaries.pictures.aviation
Subject: Boeing Model 40
Date: 15 Aug 2017 06:58:58 -0700
Organization: NewsGuy - Unlimited Usenet $23.95
Lines: 94
Message-ID: <omuun20ha4@drn.newsguy.com>
NNTP-Posting-Host: pf7740941d5483564b141afa3e333c3c2ef055e4480437026.newsdawg.com
User-Agent: Direct Read News 5.60
X-Received-Bytes: 4322
X-Received-Body-CRC: 2318084606
Xref: news.nzbot.com alt.binaries.pictures.aviation:6373
https://en.wikipedia.org/wiki/Boeing_Model_40
The Boeing Model 40 was a United States mail plane of the 1920s. It was a
single-engined biplane that was widely used for airmail services in the United
States in the 1920s and 1930s, especially by airlines that later became part of
United Airlines. It became the first aircraft built by the Boeing company to
carry passengers.
In 1925, the US Post Office issued a requirement for a mailplane to replace the
ex-military DH-4s then in use. The new aircraft was required to use the same
water-cooled Liberty V12 engine as used by the DH-4, of which large stocks of
war-built engines were available. The resultant aircraft, the Boeing Model 40,
was a conventional tractor biplane, with the required Liberty engine housed in a
streamlined cowling with an underslung radiator. The aircraft's fuselage had a
steel tube structure, with an aluminum and laminated wood covering. Up to 1,000
lb (450 kg) of mail was carried in two compartments in the forward fuselage,
while the single pilot sat in an open cockpit in the rear fuselage. The wings
and tail were of wooden construction, and the Model 40 had a fixed conventional
landing gear.
The Model 40 made its first flight on July 7, 1925. Although the prototype was
purchased by the US Post Office, the production order went to the Douglas M-2.
Role
Mail plane
Manufacturer
Boeing
First flight
July 20, 1925
Introduction
July 1, 1927
Primary users
Boeing Air Transport
Varney Air Lines
Pacific Air Transport
Number built
ca. 80
The Contract Air Mail Act of 1925 set out the gradual privatization of the Post
Office's Air Mail routes. In late 1926, bids were requested for the main
transcontinental trunk mail route, which was to be split into eastern and
western sections, with Boeing bidding for the western section. Boeing revived
the design for the tender, with the Model 40A replacing the Liberty engine with
a 425 hp (317 kW) air-cooled Pratt & Whitney Wasp radial engine, which was 200
lb (91 kg) lighter than the Liberty, ignoring the weight of the Liberty's
radiator and cooling water. The fuselage was redesigned to make more extensive
use of welded steel tubing, and an enclosed cabin was fitted between the mail
compartments, allowing two passengers to be carried as well as 1,200 lb (540 kg)
of mail. Boeing's bid of $3 per lb was much less than any of the competing bids,
and Boeing was awarded the San Francisco to Chicago contract in January 1927,
building 24 Model 40As for the route (with a further aircraft being used as a
testbed by Pratt & Whitney).
The next model to reach production was the Model 40C, with an enlarged cabin
allowing four passengers to be carried. Meanwhile, Boeing Air Transport's Model
40As were modified by replacing their Wasp engines with 525 hp (391 kW) Pratt &
Whitney Hornet radial engines to become the Model 40B-2. The Model 40B-4 was a
new-build aircraft combining the four-passenger cabin of the Model 40C with the
Hornet engine of the B-2. Production continued until February 1932.
Boeing's airline, Boeing Air Transport, commenced operations on the San
Specifications (Model 40A)
General characteristics
Crew: one
Capacity: two passengers and 1,200 lb (540 kg) mail
Length: 33 ft 2?1/4 in (10.12 m)
Wingspan: 44 ft 2?1/4 in (13.47 m)
Height: 12 ft 3?1/8 in (3.74 m)
Empty weight: 3,531 lb (1605 kg)
Max. takeoff weight: 6000 lb (2727 kg)
Performance
Maximum speed: 128 mph (111 knots, 206 km/h)
Cruise speed: 105 mph (91 knots, 169 km/h)
Range: 650 mi (565 nmi, 1046 km)
Service ceiling: 14,500 ft (4420 m)
Rate of climb: 770 ft/min (3.9 m/s)
*
|
|