Questions tagged [dc-8]
A four-engined jetliner produced by Douglas, and, later, McDonnell Douglas, from 1958 through 1972.
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Why does the use of reverse thrust on the DC-8 generate a pitch-up moment rather than a pitch-down moment?
Unlike most aircraft, the DC-8 is certified to use reverse thrust in flight (albeit only on its inboard engines). This serves as a very effective airbrake, although it also produces considerable ...
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Why was a CFM56 conversion never offered for the short-body DC-8s?
A major part of why the DC-8 hung on well into the 21st century (albeit almost entirely in cargo service) was the late-1970s/1980s conversion of 110 DC-8-60s (out of a total of 262) into DC-8-70s; the ...
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Why did the 707 and DC-8 continue to use the JT3D even after the JT8D became available?
Pratt & Whitney’s first-generation turbofan was the JT3D (a derivative of the company’s first-generation turbojet, the JT3C), which entered service in March 1961, and, due to its greater power and ...
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Why does the use of reverse thrust in flight on the DC-8 cause areas of separated/reversed airflow over the wing?
The DC-8 is one of only a few jetliners that can safely use reverse thrust in flight; even so, reversing the inboard engines (the outboard engines can only be reversed on the ground) while flying ...
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Why does the DC-8-70 have the same MTOW as the DC-8-60, despite its more powerful engines?
The DC-8-70 is a more-or-less straight reengine of the DC-8-601, replacing the obsolete JT3D-3B low-bypass turbofans of the DC-8-60 with the CFM56-2C1 high-bypass turbofan. According to Wikipedia, ...
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When, exactly, were the DC-8’s airbrakes removed?
The DC-8 was originally equipped with airbrakes on the lower rear fuselage, but these were quickly removed. Wikipedia says that they were removed before the DC-8 entered service:
[...] Douglas made ...
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Why was the DC-8-70 successful, but not the 707-700?
The first high-bypass turbofan small enough to use on a narrowbody jetliner was the GE/SNECMA CFM56, which entered service in the late 1970s as an upgrade engine for the KC-135 tanker; Boeing almost ...
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What makes it safe for the DC-8 to use reverse thrust in flight?
For most jets, the use of reverse thrust to slow down in flight, where even possible, is extremely dangerous, and strictly prohibited.
Not so on the DC-8, which is certified for the safe in-flight ...
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What is this ring-shaped device behind this DC-8's jet engine?
What is this ring-shaped device behind this Douglas DC-8's jet engine?
(YouTube)
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