Northrop's N-196 - The Passed-Over Hound Dog

The number of missile and rocket proposals developed by the various aerospace companies during the 1950s and early 1960s was truly staggering. Northrop was among them with at least a dozen different types under study, not including the Radioplane division's efforts. The N-196 was one of them. It was Northrop's submission to the Hound Dog air-to-surface missile competition.

This article originally appeared in the Northrop Grumman Engineering Department's in-house, on-line magazine Airspace, Volume 3, number 23, October 2012. It is posted here with permission and has approved for public release number 12-2189.

Northrop’s N-196 – The Passed-Over Hound Dog

By Tony Chong

As noted in “Northrop’s N-191 Proposal and Its Design Evolution,” (airspace. Aug., 2012), things are not always what they seem. The silver model in that article is a case in point.

While it was discovered stored with two legitimate model versions of the N-191 and was very close in configuration to the middle of the three designs, as noted it did not conform entirely to the illustrated and described shape. At the time it was suspected it may have been an earlier variant, but further research has uncovered an even more fascinating truth. The model was of an entirely different and earlier proposal known as the N-196.¹

N-196 was the heritage Northrop Aircraft, Inc. bid on the U.S. Air Force’s urgently requested Weapon System-131B (WS-131B), which was to provide an air-to-surface missile that could be carried by the new Boeing B-52 Stratofortress, thus giving the increasingly vulnerable manned bomber force the ability to strike heavily protected targets at a survivable stand-off range.

WS-131B was the result of a March 1956 General Operations Requirement (GOR 148) that officially recognized the need for such a weapon and formalized the request to the industry. The requirements also included Mach 2 or greater speed at 55,000 feet with a range of 350 nautical miles. It was to be armed with a nuclear warhead.

Northrop’s bid was a missile made of conventional aluminum sheet metal for ease of assembly. Length was to be 38’9” long with a span of 15’. The design featured a moderately swept high-wing arrangement with a similarly-shaped tail with an all-moving ventral vertical fin. The vehicle had a dorsal inlet with boundary layer gutters between the inlet and fuselage body.

Power was to be provided by a General Electric J85 afterburning turbojet with a Fairchild J83 turbojet as an alternative engine. Solid-propellant rocket-powered engines were also considered by the Northrop design team but rejected as it was felt it would push the vehicle beyond currently established “state-of-the-art” speeds, delaying a rapid introduction into the operational inventory.²

Performance was projected to meet the Mach 2 speed and 350 nautical mile range requirement with a 60,000’ ceiling instead of the 55,000’ requested. Weight was to be 6,850 lbs. with a 1,800 lb. warhead. Projected accuracy of the operational missile, or Circular Error Probable (CEP), was to be 3,560 feet.

Interestingly, the N-196 featured a bomb bay located at the missile’s center of gravity instead of a nose-mounted integral warhead. Northrop’s vision was to allow the vehicle to perform a free-fall warhead drop which would keep the missile flying. After delivery it could then provide immediate bomb damage assessment reconnaissance and operate as a post-strike decoy for additional B-52 survivability.

In addition, alternative payloads would allow multiple target strike options. If the target area was low-threat, the bomb drop could be accomplished with the N-196 still attached to the B-52 wing pylon. Reusable missile launch training could also be accomplished by attaching a parachute recovery system to the vehicle to keep costs down.

Using a 10,000 lb. bomb load for the Stratofortress, Northrop estimated the increased stand-off strike radius using a single N-196 to be 192 nm for a B-52D model and 224 nm for the G model. If two N-196s were carried, the strike radius became 34 nm for the D and 98 nm for the G.³

The N-196 was to be the joint effort of the Northrop Aircraft Inc.’s Aircraft Division, Radioplane Division and Anaheim Division, with program lead by Aircraft Division. By this time (July 1957), William F. Ballhaus had succeeded Edgar Schmued as engineering V.P. while retaining the Chief Engineer title. Welko Gasich continued as Preliminary Design Chief (see airspace. Sept. 2012).

WS-131B was won by North America Aviation. Deployed in 1959, the resulting missile was known as the GAM-77 Hound Dog. Post-1962 it was known as the AGM-28A/B. By then the Air Force viewed the Hound Dog as an interim weapon until the Douglas GAM-87 (AGM-48) Skybolt air-launched ballistic missile became operational. Skybolt was cancelled in 1962, so the Hound Dog soldiered on, finally being retired in 1976.

As for the N-196, it would be logical to assume there might be a link between it and the PD-0806 N-191 design. But according to retired Northrop Grumman engineer Jerry Huben, who drew up both vehicles, there was no “relativity” between the two.⁴

As the N-191 version was nearly three times the size of the N-196, that is probably so. Yet it does illustrate that the design options for a given set of parameters (e.g. Mach 2+ speed with dorsal inlet) often produce strikingly similar results; much to the chagrin of future historians trying to piece together the past from out-of-context information and artifacts.

But then again, the thrill of the hunt and the excitement of discovery are part of the allure of historical research.

Tony Chong is a historian, photographer and a contributing editor to Airspace. He leads activities in the Aerospace Systems Display Model Shop and works in El Segundo.

Footnotes

1.  Northrop N-numbers show a lot of non-chronological assignments in that period, as if some batches of projects were numbered out of sequence at a later date. It is not positively known whether this was a deliberate act of disinformation or merely the result of internal bureaucracy, but the author suspects the latter.

2.   Report No. NAI-57-790 Management Proposal for Weapon System 131-B (Northrop Model N-196) July 1957, Northrop Corp., Hawthorne, CA, July 1957, 2, declassified per DOD DIR 5200.10. July 1967.

3.   Ibid, 5

4.   Email from Jerry Huben to author, 16 October 2012.

 References

1.  Report No. NAI-57-790 Management Proposal for Weapon System 131-B (Northrop Model N-196) July 1957, Northrop Corp., Hawthorne, CA, July 1957, declassified per DOD DIR 5200.10. July 1967.

2.   The Evolution of the Cruise Missile, by Kenneth P. Werrell, Air University Press, Maxwell AFB, 1985. It can be found in pdf. format here: http://aupress.au.af.mil/digital/pdf/book/werrell_cruise.pdf

Photo Captions

1. 

 

This artist’s concept appears a lot rougher in finish than a lot of the other Northrop art of the period, but it is not totally out of the norm as a stylistic approach to product representation. The N-196 shows its ventral tail quite well in this piece. Unfortunately the artist’s name is not visible. Photo credit: Tony Chong collection

2.  

This 3-view drawing details the general arrangement and some scrap views of the N-196 design, including B-52 pylon and wing. Note the bomb bay in the missile body. Photo credit: Tony Chong collection

3. 

Compare this drawing of the PD-0806 to the previous 3-view. While strikingly similar, there are differences in the configuration, mostly in the cruciform tail and short body length aft of the horizontals of the N-191 versus the two horizontals with ventral fin and extended body aft of the tail surfaces of the N-196. Photo credit: Tony Chong collection

4. 

This upper left front quarter shot of the model shows the dorsal inlet in good detail. Photo credit: Tony Chong

5.

 

  
A look at the upper right rear quarter shot of the model shows the smooth finish on the dorsal tail area. As noted in the N-191 article, the quality of the finish indicated that the either the repair was spectacularly well done or that the vehicle only had three tail surfaces to begin with, meaning it was an earlier variant or a different vehicle. The answer seems pretty conclusive now. Photo credit: Tony Chong

6.

 

This top view shows the wing leading and trailing edge shapes and the corresponding similar tail surface shape. Again, note the length of the aft body with exhaust nozzle. Photo credit: Tony Chong

7.

A shot of the belly of the model reveals the broken ventral tail fin. Unfortunately no control surface lines or bomb bay doors were draw onto the model. Photo credit: Tony Chong

8.

 

A North American Aviation GAM-77/AGM-28 Hound Dog in flight shows off the missile’s configuration. The large belly pod housed the Pratt & Whitney J52-P-3 turbojet engine. Photo credit: U.S. Air Force

9.

 

This photo shows a Boeing B-52F Stratofortress taking off with two GAM-77/AGM-28 Hound Dogs, one under each wing. N-196 carriage would have been similar. Note the amount of smoke produced by the eight Pratt & Whitney J57-P-43W turbojet engines. B-52 minimum interval take-offs (MITOs) were quite spectacular to see in large part because of the smoke. Photo credit: U.S. government 

Approved for Public Release: Northrop Grumman Case 12-2189, 12/18/12