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Pet Peeve Alert
Re: "YF-23 Designer" assertion...
Anyone see this? I can't access the full article because it is paywalled.
YF-23 Designer Offers His Take On Boeing’s F-47 NGAD Configuration
I read the article, nothing fantastic there. We will have to wait and see what the true configuration is.
Looks exceedingly unimpressive. 0 wow factor.
The patent (see attached) doesn't list Darold Cummings. Yet his LinkedIn says he was the YF-23 Chief Configuration Designer from 1982 to 1988, coming over from Rockwell/NAA.
Accd'g to Wikipedia, in late 1981 Bob Sandusky and his small team came up with the basic YF-23 configuration. I know Yu Ping Liu was the observables guy and Merle Jager was the aerodynamicist. They and the others on the patent are shown in the reunion photo (ex. Walt Fellers, who passed in 1988).
Is this a case of "success has many fathers, but failure is an orphan”?
 

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Have checked Metz book. Interesting. No single mention of Cummings. Still ... I know how 'fathers' circle being made sometimes (especially in the complicated case of Northrop LO projects), but in this case just noticing the fact. Of course you'd remember recent Cummings article/memories for LeFana.
 
Accd'g to Wikipedia, in late 1981 Bob Sandusky and his small team came up with the basic YF-23 configuration. I know Yu Ping Liu was the observables guy and Merle Jager was the aerodynamicist. They and the others on the patent are shown in the reunion photo (ex. Walt Fellers, who passed in 1988).
I think that "design" ends up being a broad church, from program manager down to a subcontractor that designed some specific flange or seal.

In this case the 1981 configuration was pretty bare bones and would nicely tie in with Cummings' bio dates for coming in as air vehicle configuration design chief to go through preliminary and detail design and get a bunch of parts released to be built.
 
I did not see Cummings name in other publications as well including Metz's book. He does not show up in the two volume set of The Aircraft Designers which chronicles the Northrop, Grumman and NG programs, their principle design personnel and history, I do recommend the two books, very good reading.
 
I scrolled through John Cashen's second interview with Peter Westwick, where he discusses the early days of the YF-23. He makes no mention of Cummings. I've never before heard the job title "Configuration Designer". I suspect it has more to do with producing drawings for configuration management than designing the air vehicle itself.
 
Cummings wrote two-page memo illustrated with his take on evolution steps of 1981 Northrop pre-ATF design (attached in nano resolution) with ventral intake that Sandusky 'gave to him' to final design for 'Pioneers of Stealth'. Basically much extended version of memo was published in Le Fana with the same schematics, but Metz book doesn't describe Northrop ATF development path like this (I can mistaken with my impression though). Just noticed that book rather economical with engineering staff names except very few well known.
 

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Cummings wrote two-page memo illustrated with his take on evolution steps of 1981 Northrop pre-ATF design (attached in nano resolution) with ventral intake that Sandusky 'gave to him' to final design for 'Pioneers of Stealth'. Basically much extended version of memo was published in Le Fana with the same schematics, but Metz book doesn't describe Northrop ATF development path like this (I can mistaken with my impression though). Just noticed that book rather economical with engineering staff names except very few well known.
Cummings presented material in 2016 on his YF-23 configuration work. He also says he created the novel Christmas Tree concept. He mentioned Sandusky hired him from Rockwell/NAA to design the next Air Force fighter.

A 5-min segment starting at 22:04
www.youtube.com/watch?v=V6G8jk8GYdY

BillRo's understanding is that Tom Dobrenz came up with Christmas Tree "but Darold Cummings' (Config Manager) name is on the drawing."

In my experience, all initial aircraft designs had a configurator, defined as the person who literally draws the vehicle -- typically its general arrangement and inboard profile -- using a pencil on vellum, or on a CAD system. I've worked with some who were/are true aeronautical conceptualizers, synthesizers, even inventors ... but many were/are glorified draftsman. Nonetheless it's always a team effort, no matter who seeks the headline credit.

Edit: made reference to an earlier posting pertinent to this discussion.
 
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Cummings' YF-23 contributions, as described in the article and entry in 'Pioneers of Stealth' book concern the very initial stages of the YF-23. He joined Northrop in August 1982 then had to wait while he got the clearance needed. Left in 1988.

Some other material in "Pioneers of Stealth" suggests the very early 'stealth fighter' design was drawn by Tom Dobrenz I think.

Bob Sandusky in the role of Chief Engineer would not in any way be responsible for drawing the actual aircraft configuration. He hired Darold Cummings as Chief Configurator, which implied Cummings maybe has some other configurators under him?

Its possible that Sandusky described something to Cummings, Cummings as Chief Configurator drew a basic layout sketch on a scrap of paper and handed it to his guy Tom Dobrenz who actually drew up the official drawing with Cummings and then Sandusky approving it.

Who "designed" this shape?

Using the example of the Su-27, Oleg Samoilovich told the young engineer Vladimir Antonov to draw something using the basic idea of the T-4MS lifting body and the sinusoidal wing described in a British tech report from 1960. Antonov did drawings.

The initial Su-27 configuration T-10-1 was the result of a weekend get-together of Antonov, Samoilovich, and two other senior designers. It looked very pretty, but they couldn't figure out where the landing gear should go.

The design then passed to several other Chief Designers in turn, and hundreds/thousands of engineers refined all the details to get to the Su-27,

Who designed the Su-27?
 
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.Just noticed that book rather economical with engineering staff names except very few well known.
The "preliminary design phase" was from about 1979 to about 1984-5. It should be noted that Mr. Metz hired in to Northrop in 1980, and became fully occupied with the F-20 flight test and demonstration effort from before the first flight until the end of that program in 1986/7. It was not until later that he was assigned to the ATF program and had little or no exposure to the cloistered design staff prior to the time that he was "read in".
 
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According to Darold the DP- prefix stands for "Darold's Project", but I've heard "Dobrenz's Project" suggested too (could be misremembering which engineer it was named for).
 
Pet Peeve Alert
Re: "YF-23 Designer" assertion...

The patent (see attached) doesn't list Darold Cummings. Yet his LinkedIn says he was the YF-23 Chief Configuration Designer from 1982 to 1988, coming over from Rockwell/NAA.
Accd'g to Wikipedia, in late 1981 Bob Sandusky and his small team came up with the basic YF-23 configuration. I know Yu Ping Liu was the observables guy and Merle Jager was the aerodynamicist. They and the others on the patent are shown in the reunion photo (ex. Walt Fellers, who passed in 1988).
Is this a case of "success has many fathers, but failure is an orphan”?
Well technically, Sandusky and his team began working on the ATF in earnest in 1981 when they were still part of the B-2 team, but the diamond-wing & ruddervator HSF configuration that would define the YF-23 didn't emerge until 1983 or so per Wikipedia (I may be the author who added all these details last year, with Metz's and Chong's books as references ;) ).
 
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