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Bell D188A and Model 2000 VTOL Fighters (Navy F3L / USAF "XF-109")

EEP1A

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Through another amazing effort of Andreas Parsch, we could examine the actual “request for designation” for the Bell D-188 dated 29 January 1958 and 3 October 1958.(See first attachment)

In that document, statement that “The Navy has designated the subject aircraft the F3L” can be found which confirmed the rumor of F3L designation.

Attached are pictures of Bell F3L (D-188) mock-up. (source; Discovery Channel “Wings” “Straight Up” a six series program of 1996.)

Does anyone know if the mock-up for the Navy version was brand new or just repainted from USAF version? (It is also possible that the USAF version was repainted from Navy version.)
 

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overscan (PaulMM)

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EEP1A, do you have that series in any format?

I can't find it for sale...

I did find this graphic from the title sequence.
 

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EEP1A

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Some additional pictures of the Bell F3L (D-188) mock-up from the same source.
 

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EEP1A

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EEP1A said:
In that document, statement that “The Navy has designated the subject aircraft the F3L” can be found which confirmed the rumor of F3L designation.

I found the attached document "Characteristics Summary" of Bell D-188A issued by the Navy dated 28 February 1958. This official document was issued one month after the request for designation for YF-109 to the HQ USAF which stated " The Navy has designated the subject aircraft the F3L".
As there was no mention at all to "F3L" designation in this document, now I am a little bit skeptical on my previous believe that Bell D-188A was officially designated F3L.

The source of this document is
http://www.ibiblio.org/hyperwar/USN/SAC/
which lists a lot of Navy "Standard Aircraft Characteristics" and "Characteristics Summary" from WW2 era to present.

Does anybody know any site which comprehensively shows the USAF version of "Standard Aircraft Characteristics" and "Characteristics Summary"?
 

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Michel Van

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here the Bell F109 aka D-188A
F-109 1959 = Joint VTOL supersonic bomber project with Convair, based on Bell D-188A design, only made it to the mock-up stage. Eight turbojets, two rotating on the wingtips, two fixed horizontally in the tail, and two vertically through the fuselage aft of the cockpit.

note 2 jetengine in back

Mock up

and the EWR SUD "Vertikal Jäger"101-C
Joint VTOL supersonic jet fighter project with Bolkow, Heinkel and Messerschmitt
Six turbojets, four rotating on the wingtips, and two vertically through the fuselage aft of the cockpit.



archipeppe said:
pometablava said:
I don't know whether it exist any relation between both projects or it is a case of evolutive convergence (unconnected species + similar environmental conditions = similar adaptative response).

Do You mean something like Concorde-Tu 144 similarities??
Or Shuttle-Buran??

you forgot Soyuz / Shenzhou spacecraft ;)
 

weirc

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Hi, Some more information regarding the inital design of the Bell D-188

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19980228302_1998394516.pdf
 

archipeppe

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Hi folks,

here there are both versions of Bell D-188 the Navy's one and the USAF's one.

Cheers
 

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saturncanuck

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The Bell designation for this was the D-188 (Navy) and D-188A (Air Force).

To make it seem more authentic, Bell called the Navy version the "F3L-1" as this would have been the next designation in line. As "F-109" had been left open, since the redesignation of the Convair F-109 into the F-106B, Bell chose to call the Air Force version the "F-109".

However, it should be noted that neither F3L or F-109 was "officially" assigned to the D-188 project, and they were only "theoretical" designations on Bell's part.

However, what a cool plane, huh?

("Clipped Wings -- The History of Aborted Aircraft Projects", AeroFile Publications, 2007, ISBN: 978-0-9732020-4-5)
 

boxkite

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saturncanuck said:
("Clipped Wings -- The History of Aborted Aircraft Projects", AeroFile Publications, 2007, ISBN: 978-0-9732020-4-5)

Please, could you tell us more about this book? I've never heard of this publication. A short notice about the contents (the described aircraft) would be interesting.

Thanks.
 

Tailspin Turtle

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saturncanuck said:
The Bell designation for this was the D-188 (Navy) and D-188A (Air Force).

As far as I know, both the F3L and YF-109 designations were bogus. Also the Navy mockup preceded the Air Force version.

According to a Bell report, the Navy airplane was also the D-188A, although the Navy and Air Force airplanes are clearly different in detail. The "Vertiburner" was probably the D-139. I've seen conflicting reports of the configuration of the D-188. According to the plaque on this desk model, it was the lift engine concept (two J79s with a line of lift engines between them). Orionblamblam may know for sure...
 

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Orionblamblam

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boxkite said:
saturncanuck said:
("Clipped Wings -- The History of Aborted Aircraft Projects", AeroFile Publications, 2007, ISBN: 978-0-9732020-4-5)

Please, could you tell us more about this book? I've never heard of this publication.

Me neither. But Google showed me this:

http://www.aerofile.ca/clipped.html

Clipped Wings -- The History of Aborted Aircraft Projects is designed to explore 85 aircraft prototypes
that have failed to go into production from 1945 until present day.
It is a chronicle of these aircraft, and explores the development of the aircraft, their histories and the reasons for their demise.

The book is arranged by aircraft role, and features aircraft of the following types:
Fighters; Bombers; Airliners; Jet Flying Boats; VTOL; Helicopters; Flying Wings; Mixed-Power Interceptors;
Un-Winning Competitors; and Developments.
In addition, two Appendices are included at the end of the work � one dealing with aircraft projects that went as far as the mock-up stage, but were not built, and another detailing the aircraft included in the book that are preserved today.


Clipped Wings � The History of Abortive Aircraft Prototypes arranges each of the aircraft chronologically within the sections by the first flight date of each aircraft. Each aircraft listing features the following sections:
History; Summary; Disposition and Specifications.

The History section is the main body of the listing, and details the aircraft�s development from its inception and design, the contracts
(if any) and up through the building of the prototype(s) and the first flight. The details of the flight testing is also described here, and the events that led to the aircraft�s cancellation. In the Summary section, the reasons for the aircraft's cancellation are described in more detail and theories are also put forth. This section may also describe the aircraft�s designations and/or names, as well as any related technology or other aircraft that were the result of the featured aircraft�s development. The next section is Disposition, and this details the aircraft�s history after cancellation. Each aircraft that was built � or, in some cases, almost completed � is chronicled, and its final whereabouts (if known) is displayed. This section also details each of the aircraft�s serial numbers and/or constructor numbers, where known. The final section is Specifications. Here, the aircraft�s dimensions, powerplant, crew, passengers (if any), armament (if any) and performance are listed. As a standard, imperial measurements are used throughout. Where multiple types of aircraft were built, the designation and type is listed, as is the particular aircraft listed.
 

Tailspin Turtle

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A synopsis from a paper presented by a Bell engineer in 1981:

The Vertiburner concept (D-139) was powered by a single big engine (e.g. J75 or J79) with seven afterburners, one big one for level flight and six small ones for vertical takeoff and landing. The exhaust from the basic engine was diverted between the big afterburner and the six small ones accordingly. The six vertiburner "thrust chambers" could be rotated from vertical to somewhat aft for transition to and from level flight. However, the propulsion system took up far too much volume and precluded area ruling.

Bell then became aware of the J85 program at General Electric. This small engine provided much better thrust to weight than existing engines, particularly as a lift engine, overtemped for maximum thrust but used sparingly so reliability and durability was acceptable. The Lifting Engine airplane (D-188) used two J79s for high performance in forward flight with a line of five J85s between them for vertical lift. This concept also proved to require too much interior volume and was heavy, since the J85s were dead weight except for takeoff and landing.

The next step was to use the same engines for vertical and horizontal thrust. The first iteration was a four-engine airplane, with two afterburning J85s in a pod on each wing tip, similar to the independently developed VJ101C. This wasn't quite enough thrust for Mach 2 so two engines were added in the mid fuselage with a diverter valve used to provide vertical thrust at the center of gravity and afterburners in the aft fuselage for additional thrust in level flight. (See illustration below) The speed and endurance was apparently acceptable to the Navy for an interceptor mission and funded by them. However, a parallel Bell design study based on Air Force requirements necessitated more range, and therefore more lift on takeoff, so a pair of lift-only engines was added to the forward fuselage and the two afterburning engines were moved to the aft fuselage. This eight-engine configuration made sense to the Navy as well, so it was the basis for the Navy D-188A mockup and final report in December 1957 under Navy contract NOas 57-836-c.
 

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overscan (PaulMM)

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Flight Tests of a 1/8 Scale Bell D188-A Jet VTOL Airplane (Catalog #L-382)

http://gis.larc.nasa.gov/documents/643/historic/films/L-382.mpg
 

Triton

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Artist's impression of Bell D-188A (unofficial military designations XF-109/XF3L) in flight.
 

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saturncanuck

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Orionblamblam said:
boxkite said:
saturncanuck said:
("Clipped Wings -- The History of Aborted Aircraft Projects", AeroFile Publications, 2007, ISBN: 978-0-9732020-4-5)

Please, could you tell us more about this book? I've never heard of this publication.

Me neither. But Google showed me this:

http://www.aerofile.ca/clipped.html

Clipped Wings -- The History of Aborted Aircraft Projects is designed to explore 85 aircraft prototypes
that have failed to go into production from 1945 until present day.
It is a chronicle of these aircraft, and explores the development of the aircraft, their histories and the reasons for their demise.

The book is arranged by aircraft role, and features aircraft of the following types:
Fighters; Bombers; Airliners; Jet Flying Boats; VTOL; Helicopters; Flying Wings; Mixed-Power Interceptors;
Un-Winning Competitors; and Developments.
In addition, two Appendices are included at the end of the work � one dealing with aircraft projects that went as far as the mock-up stage, but were not built, and another detailing the aircraft included in the book that are preserved today.


Clipped Wings � The History of Abortive Aircraft Prototypes arranges each of the aircraft chronologically within the sections by the first flight date of each aircraft. Each aircraft listing features the following sections:
History; Summary; Disposition and Specifications.

The History section is the main body of the listing, and details the aircraft�s development from its inception and design, the contracts
(if any) and up through the building of the prototype(s) and the first flight. The details of the flight testing is also described here, and the events that led to the aircraft�s cancellation. In the Summary section, the reasons for the aircraft's cancellation are described in more detail and theories are also put forth. This section may also describe the aircraft�s designations and/or names, as well as any related technology or other aircraft that were the result of the featured aircraft�s development. The next section is Disposition, and this details the aircraft�s history after cancellation. Each aircraft that was built � or, in some cases, almost completed � is chronicled, and its final whereabouts (if known) is displayed. This section also details each of the aircraft�s serial numbers and/or constructor numbers, where known. The final section is Specifications. Here, the aircraft�s dimensions, powerplant, crew, passengers (if any), armament (if any) and performance are listed. As a standard, imperial measurements are used throughout. Where multiple types of aircraft were built, the designation and type is listed, as is the particular aircraft listed.

Isn't Google great.

Email me if anyone wants more info....
 

Tailspin Turtle

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From documents in the National Archives:

In January 1959 the Navy decided to terminate its financial support of the Bell Model 2000 program upon completion of Phase I of its contract with Bell, which would occur shortly after the mockup review scheduled for 17-19 February. At the time, the Navy thought that the Air Force was considering continuing the program and building two stripped, flyable prototypes. In late February 1959, the Navy met with Bell Aircraft to discuss the status of experimental programs connected with the Navy's contract will Bell. The Navy-sponsored tests at David Taylor and the Naval Missile Center would only be continued through June 1959. After that, Bell would have to find other funding. It was assumed that the Air Force would assume cognizance of the program in late March 1959. On 18 March 1959, the USAF Project Officer at WADC told the Navy that the USAF had dropped plans to continue development of the Bell D-188A.
 

Triton

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Full-size mockup of Bell D-188A.

Source: "Supersonic VTOL Jet" Popular Mechanics April 1961
 

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AeroFranz

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Can someone identify the tilt-duct in the background?
 

The Artist

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I'm going to have to do some digging for the exact title, but I remember seeing either this mock up or a sound stage copy used in a low grade sci-fi film. I want to say that it was called "X - The Man With X-Ray Eyes"

The main character develops the ability to see through things so he is recruited into a government agency then sent behind the iron curtain. While being extracted, his contact led him to a tarp covered shape which was revealed to be this aircraft when they dragged away the tarps. You saw them climb into the thing then they cut to cheesy animation for the flying sequence.

I saw this movie only once or twice back in the late 60s or early 70s.

Mike

Update:
I've checked IMDB and Wikipedia for information on this title and what I've found does not suggest that this is the right film. I'm still fairly sure that the letter X was somewhere in the title and that's how I ended up watching Man With X-Ray Eyes - I thought it was going to be that other movie. I'll keep looking because some additional footage of this mock up would be cool to find.
 

The Artist

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Maybe not so good.

I just checked that title in IMDB and Wikipedia and saw no mention of the events I remember.

I'm going to keep searching.

Mike
 

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Triton said:
Full-size mockup of Bell D-188A.

Source: "Supersonic VTOL Jet" Popular Mechanics April 1961

Jeez, do I have to do *all* of the blatant self-promotion around here?

Get yer fix of D-188 mockup photos here: http://www.up-ship.com/eAPR/ev2n4.htm

 

AeroFranz

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Orionblamblam said:
AeroFranz said:
Can someone identify the tilt-duct in the background?

Bell D-190:
http://www.secretprojects.co.uk/forum/index.php/topic,1222.msg10280/highlight,d-190.html#msg10280

Thanks for finding the relevant thread :)
 

The Artist

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The Artist said:
I'm going to have to do some digging for the exact title, but I remember seeing either this mock up or a sound stage copy used in a low grade sci-fi film. I want to say that it was called "X - The Man With X-Ray Eyes"

The main character develops the ability to see through things so he is recruited into a government agency then sent behind the iron curtain. While being extracted, his contact led him to a tarp covered shape which was revealed to be this aircraft when they dragged away the tarps. You saw them climb into the thing then they cut to cheesy animation for the flying sequence.

I saw this movie only once or twice back in the late 60s or early 70s.

Mike

Update:
I've checked IMDB and Wikipedia for information on this title and what I've found does not suggest that this is the right film. I'm still fairly sure that the letter X was somewhere in the title and that's how I ended up watching Man With X-Ray Eyes - I thought it was going to be that other movie. I'll keep looking because some additional footage of this mock up would be cool to find.

I believe I've identified the movie but it may take a bit to confirm this as the movie is not currently available.

"Project X" Directed by William Castle and released in 1968. Don't confuse it for the later movie about chimpanzee pilots.

You can find the IMDB page here

www.imdb.com/title/tt0063465/

I knew it had something to do with scientists and an agent going behind enemy lines.

I'll keep looking to see if I can find anything else from this movie.
Mike
 

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By reading this thread and a couple of other sources, it would seem like Bell's D-188 was the planned F3L while the D-188A was the planned XF-109. This official Bell diagram somehow contradicts this view very clearly, showing a very different D-188, while D-188A applies in fact to the would be F3L. The XF-109 is not designated, though it in turn derives from the D-188A. Any explications for this?
 

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Tailspin Turtle

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It's complicated and made somewhat more so by the fact that people, including me, have been sloppy about differentiating between the D-188 and the D-188A. The short version is that the D-188 was powered by a bank of nine J85 lift engines in the fuselage and two J79s for forward thrust. The somewhat more sensible D-188A was a very different configuration, with two afterburning J85s on each wing tip. The first iteration only had two lift/thrust J85 engines in the fuselage for a total of six engines; the second, still designated the D-188A by Bell which adds a bit to the confusion, had two additional lift engines in the forward fuselage with the original two lift/thrust moved farther back in the fuselage. The Navy and Air Force were sort of working jointly on this, with the Navy provided most if not all of the funding. The Navy and Air Force mockups were somewhat different in configuration, but both featured the later D-188A eight-engine layout.
 

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Tailspin Turtle

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With respect to the two different mockups, there was a joint Navy/Air Force review of the D-188A mockup in February 1959, by which time Bell had given the design the model number 2000 and the Navy had given notice that it were withdrawing its support of the program. My guess is that Bell had modified the D-188A mockup presented to the Navy the previous year and changed the service markings from Navy to Air Force in an attempt to get the Air Force to pick up the funding for the program.
 

Tailspin Turtle

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For much more detail and to make Scott's Christmas merrier, order his APRs that cover the Bell D109, 139, 188, and 188A projects:

Part 1: http://www.up-ship.com/eAPR/ev2n3.htm

Part 2: http://www.up-ship.com/eAPR/ev2n4.htm
 

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Tailspin Turtle said:
It's complicated and made somewhat more so by the fact that people, including me, have been sloppy about differentiating between the D-188 and the D-188A. The short version is that the D-188 was powered by a bank of nine J85 lift engines in the fuselage and two J79s for forward thrust. The somewhat more sensible D-188A was a very different configuration...

The thing I don't get:
1) the D-188 is a direct development of the D-139, which used the complex and apparetnly unsuccessful "Vertiburner" system for VTOL thrust. OK, so a major change in propulsion system merits a D-number change. Fine.
2) The D-188A seem to bear no realtionship to the D-188 whatsoever; instead it's far closer to the even earlier twin-engined D-109.

So a complete overhaul of the design *didn't* merit a change in the D-number. Buh?
 

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Apparently not. But then Bell was not so bad in terms of design and model numbers on the whole. Take Boeing for instance. Multiple designs under the same model number (I'm thinking of Model 759, for instance) that have NOTHING to do with each other whatsoever... And to complicate things more, designs with different numbers are almost exactly the same (take Model 759-211 and Model 907).

Back to the Bell D-188/A, the fact that there is no design number for the proposed "XF-109" or Model 2000 complicates the matter further. Was it still refered to as D-188A in-house? Did it get a different D-number altogether (which would not be logical, but...)? Or did the allocation of a proper model number take away the need for a D-number?
 

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I'm surprised that nobody was energetically defenestrated from the briefing room the second that the words "eight engined fighter bomber" appeared on the screen...
 

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Eight engines? I can see why the program was canceled. Imagine: In-flight refuelings every 30 minutes or so...
 

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XB-70 Guy said:
Eight engines? I can see why the program was canceled. Imagine: In-flight refuelings every 30 minutes or so...

Eight little engines or one big one. SFC and lbs of thrust is what determines fuel burn not how many engines are burning X amount of fuel.
 

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sferrin said:
Eight little engines or one big one. SFC and lbs of thrust is what determines fuel burn not how many engines are burning X amount of fuel.

Very true, although we should add that smaller engines tend to have higher values of SFC (has to do with Reynolds effects mostly). So for a total thrust output, a smaller number of engines would burn smaller quantities of fuel. This is not much of an issue for a vehicle that spends a small fraction of its mission time in hover. Furthermore, the multiple engines are essential in an OEI scenario (unless you count the bang seat as your 'plan B'). However, what does matter is the increased mass and volume of the propulsive package, which leaves little allowance for anything else (fuel). The only saving grace for this arrangement is that it gives a nice elongated shape for supersonic flight.
 

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