Boeing Model Numbers

[olbob]

I'm new here and struggling a bit to learn how this forum is operated but I would like to correct a statement that I ran across earlier today. The statement that Boeing did not have an official model number 717 is erroneous. After the 367-80 was flown came the contract for a military tanker on which I worked, The model number was 717 and I still have some layouts with that model number in the title block, dated 1954. The 367-80 was actually Model 707 and was given a spurious model number to confuse the competition. The model 717 became the KC -135.

[India Four Two]

Hi olbob,

Welcome to PPRuNe.

That's very interesting information, but it spoils my fantasy. I had thought that perhaps there was a Model 717 tucked away in a hangar somewhere, that was a dreadful failure, never to be spoken of on pain of death! ;)

That certainly doesn't apply to the KC-135.

Then of course, Boeing marketers couldn't stomach the thought of selling an aircraft called the MD-80 and attached the 717 label to it. Has anyone actually used the 717 name in the real world?

[DaveReidUK]

The 367-80 was actually Model 707 and was given a spurious model number to confuse the competition.No, the 367-80 wasn't the Model 707 but it led to two separate developments: the 707 (which bore only a superficial resemblance to the Dash 80) and the C-135 (which had more in common with its predecessor, such as the circular fuselage section, albeit wider).

The model 717 became the KC -135.Also the C-135 Stratolifter.

Has anyone actually used the 717 name in the real world? You mean like in the Type Certificate, for example ? :ugh:

[barit1]

There was a funny exchange of letters in AW&ST about 1984. I am not making this up.

One writer noted that you could deduce the number of engine on a Boeing jet from its designation: The 747 has 4 engines, the 737 has three, and the 727 has two.

Next week there was a response: "All right, wise-a**, how many engines on a 707??"

:E

[barit1]

So the question is: Does 717 apply to the C-135, or to the MD-95?

And the answer is "yes" - both types have carried the 717 designation.

Further - check out the DC-10 type certificate. You'll find there a DC-10-20, but NOT a DC-10-40. Just before NWA took delivery of their P&W-powered ships, Don Nyrop pressured McD-D into making all the marketing brochures read "DC-10-40" to imply their ship was more advanced than the -30 airplane.

But the nameplate still read DC-10-20, and its fuel burn was always greater than the -30. :ugh:

[DaveReidUK]

So the question is: Does 717 apply to the C-135, or to the MD-95?

And the answer is "yes" - both types have carried the 717 designation.Specifically, the various marks of C-135 and KC-135 were all designated 717-1xx (e.g. a 717-148 is a KC-135A) and the MD-95 became the 717-200.

[olbob]

Mr. Ried UK. Since I worked on the 367-80 I feel that I might have some knowledge about it. The Boeing model number was 707 and the prototype had that designation pasted all over the exterior. If the -80 wasn't model 707, what was it?
The I wish that I could print the some of the drawings that I have to show the progressive changes in the configuration of the 367-80 to the 717 and the 717 to the production version of the 707. The biggest change was the increased diameter in the upper lobe of the 707 to accommodate more seats abreast to compete with the DC-8 . The planform of the -80 is almost identical to the 707 but slightly smaller. The structural centerlines are identical as is the wing sweep. The -80 fuselage is slab sided where the 717 upper lobe is semi-circular, the 707 upper lobe is a larger circle that produced a crease line that does not exist on the -80 or 717. The 717 (KC-135) weighed 248,000 pounds and the 707 was something like 224,000 but the planforms were identical.
The recent "717" was a marketing gimmick, the originators paying no heed to the existence of one 717 already on the books.

[olbob]

I dug into my archives and came up with a three view of a study for the model 707-6. It is dated April of 1952. To add a bit more info. The fuselage diameter of the 367-80 is 132 inches; 717 is 144 inches; 707, 720,727,737 and 757 is 148 inches.

[India Four Two]

olbob,

I've sent you a PM. Click on Private Messages at the top right of the page.

[India Four Two]

You mean like in the Type Certificate, for example ?

Dave,

No, I meant in the "real" world. For example, did controllers say "Follow the 717" or did they say "Follow the MD-80"?

[olbob]

Forgive me but I cannot find anything regarding PM's in the upper right corner .

[DaveReidUK]

The I wish that I could print the some of the drawings that I have to show the progressive changes in the configuration of the 367-80 to the 717 and the 717 to the production version of the 707.That was my point - the 367-80 was developed into the 707 via the changes you describe.

That's rather different from the original assertion that the Dash 80 was the 707 - it wasn't, at least not the 707 as we have come to know it.

[DaveReidUK]

No, I meant in the "real" world. For example, did controllers say "Follow the 717" or did they say "Follow the MD-80"?I suspect that airworthiness professionals might take exception to the suggestion that they don't live in the real world, but I take your point.

For ATC purposes, the aircraft would be flightplanned as a B712 i.e. Boeing 717-200 and referred to by controllers as a 717.

[olbob]

I would be interested in your describing to me how the 707 " evolved" from the 367-80 and what changes occurred during this " evolution".

[DaveReidUK]

I would be interested in your describing to me how the 707 "evolved" from the 367-80 and what changes occurred during this "evolution".Well, according to an earlier post:

The biggest change was the increased diameter in the upper lobe of the 707 to accommodate more seats abreast to compete with the DC-8 . The planform of the -80 is almost identical to the 707 but slightly smaller. The structural centerlines are identical as is the wing sweep. The -80 fuselage is slab sided where the 717 upper lobe is semi-circular, the 707 upper lobe is a larger circle that produced a crease line that does not exist on the -80 or 717.I couldn't put it any better than that ...

[Brian Abraham]

olbob is quite correct.

The Boeing model number 367 was applied to a number of different studies. See flying fortress | 1954 | 1103 | Flight Archive (http://www.flightglobal.com/pdfarchive/view/1954/1954%20-%201103.html?search=turboprop+aircraft+project+1940)

Boeing always referred to the Dash 80 as the 707 prototype, the aircraft even carrying the registration N70700 to so designate it.

The KC-135 went by a number of 717 designations, and 739.

Model 717-100A KC-135A 29 built
Model 717-146 KC-135A 68
Model 717-148 KC-135A 635
Model 717-157 C-135A 15
Model 717-158 C-135B 30
Model 717-164 C-135F 12
Model 717-166 KC-135B 17
Model 739-700 RC-135A 4
Model 739-445B RC-135B 10

Grand Total: 820

[DaveReidUK]

I've also seen it suggested elsewhere that the French Air Force C-135FRs consist of 6 x 717-164 and 6 x 717-165.

I don't know if that's true, although if it is it could explain why they are serialled in two different FY63 batches: 470-475 and 735-740.

I've also seen it suggested that when the MD-95 became the 717-200, Boeing redesignated all the earlier C-135s as 739-1xx (as per the RC-135s), although again that's unconfirmed.

[olbob]

I have a picture of the general arrangement of Boeing model number 707-7-24, identified as the 367-80. I tried to post an attachment but it appears that I am not permitted. I'll keep trying.

[barit1]

I too have seen the Boeing progression drawings; I particularly recall the fuselage cross-section differences. The -80, C-135, and 707/720 were all unique in response to differing market desires. The 727 IIRC was same as the 707, but the 737 had a smaller lower (cargo) lobe.

Further, early on the 707 was available in different cabin lengths, to the extent even of a special model (707-138) for QANTAS long thin routes.

The point that was made in that presentation was that Boeing was responsive to market forces, whereas competitors - not so much.

[olbob]

You are correct. The basic configuration of the 707 was not changed but the fuselage dia. was refined and adjusted to meet customer requirements. The 707,720,727, and 737 all had the same upper fuselage dia. but the 727 and 737 had a shallower lower lobe. The KC-135 had a smaller upper fuselage dia. than the commercial 707 but the VC-137 was the same.