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Author Topic: CX-HLS (Cargo Experimental, Heavy Logistic Support) designs & derivatives  (Read 62019 times)

Offline pometablava

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Giants of the Sky by Bill Gunston
ISBN 1-85260-258-9

LOCKHEED MARTIN C-5 GALAXY: WarbirdTech 36


In 1960 the USAF launched Project Forecast which called for the world's biggest logistic transport, the CX-4, in the 600,000 lb category. It should be a jet. The only study I know comes from Douglas but I have no details about its Model Number. I guess that Boeing and Lockheed carried out its own designs.

With all the data generated under CX-4 study, the USAF launched an specification for a CX-HLS aircraft. The winner was Lockheed (C-5 Galaxy)

Douglas submitted several designs: Model D-890, D-895, D-900. According to "Giants of the Sky", the definitive design was D-916 while D-920 was the submission for the Wardbirdtech volume.

I have included to this post the D-920.

The last scan is Boeing C-5A from Giants of the Sky. Anybody knows Boeing's model number for it?

Offline TinWing

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Douglas submitted several designs: Model D-890, D-895, D-900. According to "Giants of the Sky", the definitive design was D-916 while D-920 was the submission for the Wardbirdtech volume.


Here is the D906 from "McDonnell Douglas Aircraft Since..."
« Last Edit: April 24, 2006, 05:34:22 am by TinWing »

Offline lark

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Any one who haves the Boeing modelnumber of
the Boeing CX-HLS design ?

Thanks.

Offline Schorsch

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In 1960 the USAF launched Project Forecast which called for the world's biggest logistic transport, the CX-4, in the 600,000 lb category. It should be a jet. The only study I know comes from Douglas but I have no details about its Model Number. I guess that Boeing and Lockheed carried out its own designs.

Are you sure about that? The CX-4 was to have 6 engines and these were low-bypass, similar to Starlifter. Lots of paper-design was made by the big three. CX-4 was discarded and CX-HLS was born with all designs of Douglas, Boeing and Lockheed similar in shape. Lockheed was chosen due to price. Boeings design used a little bit more edge-technology.
However, the pictures you have posted look more like Douglas' proposal for CX-HLS.

Offline pometablava

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Schorsch

This is taken directly from Bill Gunston's "Giants of the Sky":
Quote
In 1960 the USAF launched Project Forecast which called for the world's biggest logistic transport, the CX-4, in the 600,000 lb category. It should be a jet

And the pic I posted as "Douglas CX-4" came form an old magazine where it is identified as Douglas CX-4. I'll try to identify the magazine identity and get more info.

Nevertheless the aircraft in the pic has 6 engines and look similar to that on the C-141....so it match your description about the CX-4 study. ???






Offline Schorsch

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This is the Lockheed proposal for the CX-4.

Offline TinWing

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This is the Lockheed proposal for the CX-4.


What was the "STF 200C" engine?  Was this some sort of re-fanned variant of an existing engine?


Offline Sentinel Chicken

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Quote

What was the "STF 200C" engine?  Was this some sort of re-fanned variant of an existing engine?


The STF200 was one of Pratt & Whitney's early demonstrators for a high-bypass ratio turbofan engine. It had a bypass ratio around 2 which is good considering that first generation of turbofan engines only had bypass ratios of around 1.2-1-4. Unfortunately for PW, though, GE made a breakthrough that gave its' TF39 a bypass ratio of 8 and a better fuel burn despite improvements to the STF200 that got its BPR up to around 3-3.5.
« Last Edit: April 27, 2006, 12:34:10 pm by Sentinel Chicken »

Offline lark

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The Douglas CX-4 which Pometablava put in this file came from :
FLIGHT Internatonal 28 November 1963 - page 853

Caption reads as follow : Douglas Proposal for the USAF CX-4 study
for a large logistics cargo transport (see " USAF Global Freighter"
column 1 )

Offline TinWing

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Quote

What was the "STF 200C" engine?  Was this some sort of re-fanned variant of an existing engine?


The STF200 was one of Pratt & Whitney's early demonstrators for a high-bypass ratio turbofan engine. It had a bypass ratio around 2 which is good considering that first generation of turbofan engines only had bypass ratios of around 1.2-1-4. Unfortunately for PW, though, GE made a breakthrough that gave its' TF39 a bypass ratio of 8 and a better fuel burn despite improvements to the STF200 that got its BPR up to around 3-3.5.

I wonder if the STF200 was an all-new design or similar in concept to the far later refanned JT8D-200 series?

It is noteworthy that Rolls-Royce was promoting a refanned Medway in this era as well - the 22,000lb st RB177-2.

The great irony is that it took longer than expected for high bypass ratio turbofans to dominate the commercial airliner market.

Offline Pioneer

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Does anyone have any information, drawings and specifications for Martin Marietta and General Dynamics CX-HLS (Cargo, Experimental-Heavy Logistics System), that would later be won by Lockheed with its Model 500, that would become famous as the C-5 Calaxy.

Regards
Pioneer
And remember…remember the glory is not the exhortation of war, but the exhortation of man.
Mans nobility, made transcendent in the fiery crucible of war.
Faithfulness and fortitude.
Gentleness and compassion.
I am honored to be your brother.”

— Lt Col Ralph Honner DSO M

Offline boxkite

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"Der Flieger" issue 1/1965 (page 7) printed this artist's impression as Boeing CX proposal.

Offline boxkite

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This Lockheed proposal of a cargo plane for the Military Air Transport Service of the USAF was released in "Der Flieger" number 1/1966 (page 7). Mistakenly the author of the caption described the aircraft as a future space ??? transport aircraft, but I hope he didn't make a mistake regarding Lockheed as the home of this design.

Any idea about the background of this layout (model number etc.)?
« Last Edit: August 16, 2006, 02:04:47 pm by TinWing »

Offline TinWing

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This Lockheed proposal of a cargo plane for the Military Air Transport Service of the USAF was released in "Der Flieger" number 1/1966 (page 7). Mistakenly the author of the caption described the aircraft as a future space ??? transport aircraft, but I hope he didn't make a mistake regarding Lockheed as the home of this design.

Any idea about the background of this layout (model number etc.)?

1.  This is indeed a Lockheed design.  The big question is whether or not it was a Skunkworks project?

2.  By 1966, this design was over 5 years old.

3.  This isn't a "space transport," but I also have a hard time believing that the transport of cargo was intended as the primary role in 1961.

Offline TinWing

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1.  This proposal dates from 1961, the right date for the SLAB program.

2.  The SLAB requirement apparently was for a 500,000lb MTOW aircraft.  In my estimation, this drawing depicts a large aircraft.

3.  Boxkite, please don't take offense at my renaming of your thread.