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.
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
