Fanged Butterfly - Northrop's First Vee-Tailed Fighter Proposal

It has been a long and very busy winter for me. Finding time to post has been extremely difficult during this period. Fortunately, it appears I now have some time to return to this forum and showcase some more of my articles that were published in the various in-house Northrop Grumman magazines over the last few years, in this case Airspace.

The Fang has always been an interesting project to me as it is a really cool design that seemed to come out of nowhere. But as we all know, things do not occur in a vacuum. The story of this proposal is a lot more complex than generally presented, and extremely pivotal to the future success of the Northrop company.

As a side note, irony has always been a mostly unintentional consequence of human behavior and action. This story is no different. The fact that Oliver Echols passed over Eugene Root, a Cal Tech graduate, noted Douglas Aircraft and RAND Corp. engineer for Edgar Schmued, who then proceeded to recruit his own Cal Tech grad, former Douglas and RAND engineer William Ballhaus, who in turn hired Welko Gasich (Stanford, Cal Tech, Douglas and RAND) and Tom Jones (Stanford, Douglas and RAND), is too delicious for words. It seems that the Cal Tech, Douglas and RAND influence was going to be at Northrop no matter what. 

Whether it would have produced the same results is another story. 

This article was originally published in the Northrop Grumman Engineering Department's in-house, on-line magazine Airspace, Vol. 3, No. 22, September 2012. It is re-posted here with permission and has approved for public release case number 12-1832.     

Fanged Butterfly – Northrop’s First Vee-Tailed Fighter Proposal

By Tony Chong

The appointment of Edgar O. Schmued to the position of Assistant Chief Engineer in November 1952 by then-Northrop Aircraft, Inc. General Manager Oliver P. Echols had two immediate and far-reaching consequences. The first was the hastened resignation and retirement of John K. “Jack” Northrop from the company he founded in 1939. The second was that the company’s engineering department would now undergo a major change in staffing and design philosophy which would eventually result in the T-38 and F-5 series of aircraft.

Echols picked Schmued, who built his reputation at North American Aviation as one of the designers of the P-51 Mustang and F-86 Sabre, over the objections of Jack Northrop. Northrop wanted to hire Eugene Root, a talented Douglas and RAND Corporation engineer, to be his assistant and eventual successor as Chief Engineer. Echols overruled him.

Northrop, realizing he had lost control of not only his company but his Engineering department as well, retired in disgust. After the bitter loss of the YB-49 and YRB-49 Flying Wing programs, and with his growing ill-health and other personal problems over the last three years, this was the final blow. The founder was out and a new regime took over.¹

Echols assumed the title of President of the company from Jack Northrop. He immediately elevated Schmued to Vice-President of Engineering.

Schmued, in turn, began to bring over engineers from North American to fill out the department’s ranks. However, he offered the job of Chief Engineer to Dr. William F. Ballhaus, a 34-year old Stanford and Cal Tech graduate who was then Chief of Preliminary Design at Convair in Ft. Worth, TX.²

Ballhaus accepted the offer and recruited two other Stanford graduates to join him: Welko E. Gasich and Thomas V. Jones. Gasich became Chief of Preliminary Design and Jones took the position of Assistant Chief Engineer to Ballhaus.³ Jones would later become President and CEO of Northrop Corporation and Gasich a corporate V.P. and General Manager of its Aircraft Division.

Veering away from the large, complex fighter designs Northrop was known for, Schmued initiated the N-102 program in response to a new U.S. Air Force General Operating Requirement for a light-weight supersonic interceptor. The N-102 was to be less-complex and less-costly than contemporary fighters and be multi-purpose in function as well. Due to his aversion to the arachnid names used on the company’s previous fighters (Black Widow and Scorpion), Schmued named the new aircraft “Fang.”⁴

The Preliminary Design Department issued report P.D. 152 on January 19, 1953 that detailed the new fighter. Considering Ballhaus came from Convair it is not surprising that the initial proposal was heavily influenced by that company’s design thinking. Specifically, the N-102 featured a delta-wing. More interestingly, the Fang also had a butterfly, or vee-tail, which was used on one of the precursor interceptor designs that eventually led to Convair’s XP-92.⁵

Delta-wings and vee-tails were not uncommon design elements in many aircraft company studies around the world during the war and post-war period. Besides Convair, U.S. firms such as Lockheed, McDonnell, Republic, Chance Vought and North American all had concepts that explored one or both of these features.⁶

The Fang, however, was one of the first designs to combine the two into one vehicle.

With a projected 23 foot span and a 41 foot length, the N-102 was also one of the smallest supersonic jet fighters proposed in the 1950s. It was essentially wings, tails and a man wrapped around a big, powerful turbojet engine.⁷

The Fang also featured a unique power-plant arrangement where a single airframe could accommodate four separate engines. The concept was to fit the engine and armaments package tailored for a specific mission into the aircraft when required.⁸

The initial offering was the Wright TJ31B3, a licensed-built Armstrong-Siddeley Sapphire turbojet with afterburner (U.S. military designation J65). Projected performance was Mach 1.85 at 35,000 feet, with a ceiling of 56,000 feet. Combat radius on internal fuel only was to be 255 nautical miles and up to 465 nm with external tanks.⁹

A non-afterburning TJ31B2 (also known as a dry J65) was an option, as was the Pratt & Whitney JT3M (military J57), both optimized for low-altitude missions such as close air support and supply line interdiction. A General Electric X-24A (military J79) turbojet gave the Fang a projected high-altitude Mach 2-plus performance.¹⁰

Baseline armament for the Fang consisted of between eighty to one-hundred 1.5 inch rockets carried in two wing-root trays that would swing down into the airstream for firing. Alternative loads included thirty 2-inch rockets, bombs (napalm or general purpose), two 20mm or two 30mm cannon, or a “special stores” (nuclear weapons) package.¹¹

Special attention was given to ease of maintainability and avionics growth, presaging the company’s emphasis on extended life-cycle costs as important factors to be considered in future warplane procurement and operation.

The vee-tailed feature of the N-102 was short-lived, however. By 1954 the butterfly was gone, replaced by a more conventional empennage with a single-vertical fin and two horizontal tail surfaces. Northrop would not revisit the idea again for decades, coming into the hardware stage at last via the wide-tailed vee of the YF-23.¹²

The conventional-tailed Fang was also larger that the initial design, growing to 30’6” in span and 45’10” in length. The swappable engine capability was retained, with the addition of the Wright J67 license-built Bristol Olympus turbojet as one of the power-plant choices. The increase in size coupled with the baseline GE J79 gave a mission radius of 365nm on internal fuel in the high-altitude day-fighter role.¹³

The modified Fang would not progress to the prototype or production stage, either. As the Air Force had already awarded a contract to Lockheed for its XF-104 lightweight supersonic interceptor in March, 1953, the N-102 was passed over. The mock-up was eventually given to the Northrop Institute in 1956 for use by its engineering students.¹⁴

The delta-wing would remain a major Northrop design feature for most of the 1950s, recurring on the proposed N-94 Navy carrier-borne day-fighter and the N-126/N-144/N-149 Delta Scorpion and Long Range Interceptor concepts, among others.¹⁵By the end of the decade, however, Schmued had left Northrop and Ballhaus became General Manager of the new Nortronics Division, taking with them the emphasis on that feature.

But the changes in design philosophy were taken to heart by the engineering department at Northrop, specifically the incorporation of the basic N-102 concepts of simplicity, light-weight size and ease of maintenance married to a platform featuring solid, supersonic performance.

This would see fruition in the Gasich version of the N-156F and T.¹⁶ Wrapped around a pair of small General Electric J85 turbojets, the N-156T would become the legendary T-38 Talon and the N-156F would sire the F-5 line of low-cost, high-performance fighters.

While his tenure was only six years long, the appointment of Edgar Schmued was critical to the company’s history as his decisions changed the look of Northrop products for decades to come. Without him, Welko Gasich and Tom Jones would not have been recruited to Northrop by William Ballhaus and it is doubtful the T-38 and F-5 series would have been successful without the efforts of these two men and the team they led.

Indeed, the influence lasts to this day as the YF-17 was a direct descendant of the F-5 and it, in turn, begat the F/A-18 stable of Hornets, Super Hornets and Growlers, the mainstay of today’s U.S. Navy carrier aviation.

While it is easy to wonder what Eugene Root would have done had he become Jack Northrop’s successor, in retrospect the choice of Edgar Schmued was not a bad one.

Footnotes

1.  Details of these events are related in the John K. Northrop Oral Interview Transcripts, University of California, Santa Barbara, Richard “Dick” A. Thurston, interviewer, 27 April 1972, 68-69; also in Jack Northrop and the Flying Wing – The Real Story Behind the Stealth Bomber, by Ted Coleman, with Robert Wenkam, 1988, Paragon House Publishers, NY, 188-191.

2.  Mustang Designer – Edgar Schmued and the Development of the P-51, by Ray Wagner, 1990, Crown Publisher, NY, 195.

3.  Ibid. Gasich, also a Cal Tech graduate, worked at Douglas Aircraft and spent some time with the NACA. Jones was with the RAND Corporation, a research and development unit sponsored by Douglas in the mid-1940s. Ballhaus also worked at Douglas before he went to Convair. Check this link for further RAND Corp. history: http://www.rand.org/about/history.html

4.  Ibid

5.  American Secret Projects – Fighters & Interceptors 1945-1978, Tony Buttler, 2007, Midland Publishing, England, 23-24.

6.  Ibid, 15-16 (Lockheed), 17-18 & 39 (McDonnell), 25-27 & 44-45 (Republic), 36-37 (Chance Vought), 49, 60-61 (North American).

7.  Lightweight supersonic fighter – Northrop Fang, Northrop Preliminary Design Department Report Number P.D. 152, Archive number TL 55,297 c.173, 19 January 1953, Hawthorne, CA. Declassified per DoD Dir. 5200.10 1 June 1965, 1.

8.  Ibid, 11.

9.  Ibid, 3.

10. Ibid, 11. 

11. Ibid, 12-13.

12. Some early Northrop A-X concepts during the 1960s featured a Y-tail configuration which could be confused for a V-tail at first glance. The small Acme Aircraft Company (Sierradyne Inc.) S-1 Sierra Sue was utilized as a flying proof-of-concept demonstrator by Northrop Corp. during that period. Designed and built by Northrop engineers Ron Beattie and Walt Fellers, Sierra Sue is now displayed at the Western Museum of Flight at Zamperini Field/Torrance Airport, Torrance, CA. For further information check this link: http://www.wmof.com/Serria%20Sue.html

13. Fang – High Altitude Day Fighter, Northrop brochure NAI-54-321, CY 110, 15 July 1954, Hawthorne, CA. Declassified per DD 254, 27 July 1964, 13.

14. Northrop – An Aeronautical History, by Fred Anderson, 1976, Northrop Corp., Century City, Los Angeles, CA, 172.

15. Complete scans of two different N-94 company brochures can be found at this great site: http://retromechanix.com/article/fighters/northrop-model-n-94-class-vf-day-fighter/. Information on the N-126/N-144/N-149 can be found in American Secret Projects, 89 and 95-101.

16. A huge and very heated internal debate occurred in Advanced Design between Gasich’s version, which had the two engines carried within the fuselage, and Schmued’s proposal, which featured under-wing mounted engine pods. Schmued’s perspective on the resolution of the N-156T configuration fight is found in Mustang Designer, 201.

References

A great book on U.S. concepts, proposals, prototypes and production aircraft is: American Secret Projects – Fighters & Interceptors 1945-1978, by Tony Buttler, 2007, Midland Publishing, England.

The standard reference for Northrop Aircraft, Inc. products and history is: Northrop – An Aeronautical History, by Fred Anderson, 1976, Northrop Corp., Century City, Los Angeles, CA.

Despite being full of errors and flawed memories, Coleman’s book is fascinating. Especially interesting is his undisguised animosity toward Oliver Echols, Edgar Schmued and Whitley Collins, the man to succeed Echols as President of Northrop in 1954. Jack Northrop and the Flying Wing – The Real Story Behind the Stealth Bomber, by Ted Coleman, with Robert Wenkam, 1988, Paragon House Publishers, NY

Edgar Schmued’s opinions of Jack Northrop are equally acerbic as related in his biography. It makes for a classic case of opposite points of view with the rising specter of clashing loyalties and self-interest: Mustang Designer – Edgar Schmued and the Development of the P-51, by Ray Wagner, 1990, Crown Publisher, NY

Another fascinating read is Jack Northrop’s oral interview, despite the self-acknowledged faulty memories and deliberately forgotten painful events: John K. Northrop Oral Interview Transcripts, University of California, Santa Barbara, Richard “Dick” A. Thurston, interviewer, 27 April 1972

The following Northrop report and brochure were especially helpful:

Lightweight supersonic fighter – Northrop Fang, Northrop Preliminary Design Department Report Number P.D. 152, Archive number TL 55,297 c.173, 19 January 1953, Hawthorne, CA. Declassified per DoD Dir. 5200.10 1 June 1965

Fang – High Altitude Day Fighter, Northrop brochure NAI-54-321, CY 110, 15 July 1954, Hawthorne, CA. Declassified per DD 254, 27 July 1964

Photo Captions

1.  The cover to the Northrop Preliminary Design Report P.D. 152 features a nice artist’s concept of the butterfly-tail Fang. This is probably one of the more pleasing angles of the aircraft. Note the size of the pilot and shape of the canopy relative to the rest of the vehicle. Tony Chong collection

 

2.  Another artist’s impression, this time of three Fangs in formation peeling off into action. As noted by his signature, the image was done by Jack Leynnwood, who was also a noted box-top artist whose work was featured on many Revell and Aurora plastic model kits. Tony Chong collection  

3.  This 3-view of the butterfly-tail Fang shows how the razor-back canopy arrangement combines with the prominent engine housing to give the vehicle a hulking appearance in profile despite its diminutive size. Note the nose gear location in front of the inlet. Foreign object ingestion from normal gear cycling would be a concern if the N-102 was ever put into operation. Tony Chong collection

 

4.  The inboard profile with cross-sections reveals how much of the lower part of the airplane is taken up by the engine, in this case a Wright TJ31B3, or J65 with afterburner. Tony Chong collection

5.  Ease of maintenance was a prime driver in the N-102 design. The mid-fuselage wing arrangement helped facilitate engine removal. The forward-hinged windscreen would show up in the N-156F and T designs later in the decade. Tony Chong collection

6.  The production breakdown of the N-102 vee-tail is illustrated in this image. Aluminum 75ST would be used extensively throughout the vehicle, with steel and titanium envisioned for high-load areas. The drawing also shows the different wing construction methods. The lower cut-away details the standard production structure of forged spars and ribs with honeycomb skin, while the upper art represents the mass production structure using integral spars, ribs and cover. Tony Chong collection

 
7.  The upper art shows the two-gun T-182 30mm cannon placement and the lower the two-gun T-160 20mm cannon option. The T-182 would carry 160 rounds per gun while the T-160 had 200 rounds per gun. The link and case ejection chutes were positioned a little aft of the inlet.  Tony Chong collection  

8.  The various scrap views above show the different rocket armament options on the N-102. The flip-down trays are installed near the wing root and close to the inlet, but hopefully far enough away that the rocket motor exhaust plumes or any launch debris would not be ingested into the engine. Tony Chong collection
  

9.  Small pen & ink drawings are typically sprinkled throughout the reports and manuals dating from that period. This one shows the Fang launching a rocket salvo at an unseen enemy. A typical salvo was projected to be forty rockets. One suspects the fire and smoke of forty rockets leaving the aircraft would be far more spectacular than the benign environment shown in the art above. Tony Chong collection

 

10. Rocket salvo “probability of kill” patterns in the report featured the MiG-15 as the target. The appearance of this Soviet-made fighter during the Korean War made a huge impression on Allied air forces and became the focus of contemporary air-engagement studies. Tony Chong collection

11. It appears that the only surviving Fang in-house model still inside the company is this vee-tail example. Originally in the old Heritage Hall on the Hawthorne site, it now resides in the Building 202 ASDC Lobby (Lobby 10) in El Segundo. The visible split lines indicate the model had interchangeable parts, perhaps a possible two-seat forward fuselage option. Photo credit: Tony Chong

12. As with most models of the period, some damage has occurred over the years. The tips of both tails are chipped and the decals are crackled. All things considered, though, it is in relatively good shape. Again, elevated angles that disguise the large engine housing make the vee-tail Fang much more pleasing in appearance.  Photo credit: Tony Chong

13. This underside view shows the large inlet and huge engine housing. It appears the housing is a separate section from the nose and upper fuselage as well. The damage to the port tail is quite apparent in this shot. The writing on the engine housing says: “X-24A – Max Mach 2.0+ – Combat Ceiling 67,000’.” The X-24A was a G.E. engine that carried the military designation of J79. Photo credit: Tony Chong

14. By 1954 the butterfly-tail gave way to the more familiar and sleeker version of the Fang with the conventional empennage. The aircraft also grew in length and span. Other changes included a cambered wing, pointed wingtips, a shift of the wing to the upper part of the fuselage, a slimming of the upper and lower fuselage and the addition of a bubble canopy for increased pilot visibility. Note the new bifurcated inlet. Tony Chong collection

15. Probably the prettiest of the variants was the two-seat conventional-tailed Fang. Length and span remained the same as the single-seat conventional-tail version. Tony Chong collection

16. Though difficult to see, the Fang patent was assigned to Edgar Schmued and Welko Gasich in May, 1957. Credit: U.S. Patent Office

 

17. This final piece of in-house Northrop concept art, signed by Todd, is from the company’s NAI-54-321 brochure on the Fang High-Altitude Day-Fighter. It appears to be the basis for the patent art in the previous illustration. This is an especially pleasing angle of view on the vehicle and a dramatic piece of art as well. Tony Chong collection

Approved for Public Release: Northrop Grumman Case 12-1832, 10/22/12