"For the Snark was a Boojum, you see."

 I really enjoyed writing this piece. How often does one get to quote Lewis Carroll in the title? Plus Boojum is a really cool name to say.

This article was originally published in Airspace vol. 2 no. 11, September 2011. It is posted here with permission and has approved for public release case number 12-1433.

“For the Snark was a Boojum, you see.”*

By Tony Chong

Perhaps no two companion aerospace projects have had a more whimsical set of names given to them than the heritage Northrop Snark and Boojum.  Yet, like the fantastical creatures featured Lewis Carroll’s nonsensical poem, the Snark and Boojum were meant to be deadly as well.

In 1945 the U.S. Army Air Force’s Air Material Command issued a block of ten MX-designated research and study contracts to several companies for various advanced missile designs.  Half of them were allotted for subsonic and supersonic Surface-to-Surface Missiles, of which three were to be ultimately built as air-breathing cruise missiles.

Northrop was awarded one of these contracts, MX-775, in March of 1946.  MX-775A was for a subsonic intercontinental cruise missile, which eventually became the Snark.  The MX-775B was for a supersonic intercontinental cruise missile.  It was christened by the company as Boojum.

In December of 1946, the funding for Snark was deleted from the budget, but the more technically difficult Boojum survived.  After lobbying by Jack Northrop himself, Snark was reinstated in 1947 with the promise that it would only take two and one-half years to develop.  Boojum was retained as well, but now as the follow-on system to Snark.

1947 saw the formation of the U.S. Air Force as its own branch and the Snark was designated SSM-A-3 and the Boojum SSM-A-5.  “X” was added as a prefix to indicate the experimental nature of the programs at this stage.

The early version of the Boojum bears a distinct similarity to the early Snark.  Both had in-house N-25 designations, with N-25A for Snark and N-25B for Boojum (each would acquire new N-numbers later on, the Boojum in particular being noted as N-217 in some internal documents).  Both also carried thin, highly swept-wings on a long, semi-tailless fuselage.  A small vertical fin adorned each vehicle’s aft end.  However, Snark had a high-mounted wing with a flush belly inlet, while Boojum sported a mid-fuselage wing and an annular inlet. 

The final Boojum version would show a radical departure from the early configuration.  Ultimately the missile was to be a semi-tailless, delta-winged vehicle that would reach 85.33 feet in length and have a span of 50.85 feet.  

Missile construction was to feature a conventional semi-monocoque fuselage with aluminum alloy-faced, honeycomb core bulkheads.  The skin of the Boojum was to be made from a non-strategic magnesium alloy.

An “ultimate short-life” afterburning General Electric J47 turbojet was to be mounted near the tips of the wings, each providing 13,620 pounds of static thrust.  Engine life was estimated to be 25 hours, but the life of the continuous-use afterburners was only required to be 4.5 hours – the duration of a typical mission at Mach 1.8 with expendable drop tank. 

Estimated top speed was Mach 2.0 at 66,600 feet, with a range of nearly 3,400 miles clean and 4,980 miles with drop tank.  Maximum ceiling and range were 70,000 feet and 3,510 miles clean or 5,080 miles with tank at Mach 1.8.  All figures factored in the 3,000 lb. “special” (nuclear) warhead as the payload.

Alternate engines were available for use, with the primary one being the proposed General Electric XJ53.  Other types, including the General Electric/Allison J35 and Westinghouse J40 were considered as well, but more as a stop-gap measure if the J47 or XJ53 were unavailable for the test phase.

Like the Snark, the Boojum was to be guided to its target by the Northrop-designed Automated Celestial Navigation (ACN) system.  This system, which marked the start of Northrop’s Electronics “Nortronics” Division, utilized an automatic day/night star-tracking sextant and associated avionics that weighed nearly one ton. 

Boojum could be rail-launched in either a single or two-stage configuration.  The first stage component was a large 80.5 foot span straight-wing attachment with wingtip-mounted fuel tanks.  The wing mounted to the belly of Boojum via a massive pylon that remained with the first stage when it detached.

Boojum was also designed to be air launched from a large carrier aircraft.  Mounted on the top of the mothership because of its size, it resembled the recently retired 747/Space Shuttle combo.

Wind tunnel and rocket-boosted atmospheric models tests of the Boojum proceeded through the late 1940s, but by the start of the new decade customer confidence in the viability, accuracy and performance of the supersonic cruise missile waned.  The program was cancelled in 1951.

Snark would continue, but its path was long, difficult and marginally successful.  While the system did eventually attain operational status with the 702^nd Strategic Missile Wing in February, 1961, its life was short.  The first U.S. intercontinental ballistic missile went operational months earlier in September 1959, rendering the in-coming Northrop vehicle obsolete.  The 702^nd SMW was deactivated four months later.  Like the Baker in Carroll’s poem, Northrop’s aptly named cruise missiles softly and suddenly vanished away, never to be met with again.

*The Hunting of the Snark by Lewis Carroll. http://books.google.com/books?id=TLoNAAAAYAAJ&printsec=frontcover&dq=The+Hunting+of+the+Snark#v=onepage&q&f=false

Additional information about the Boojum can be found at the following links:

http://www.designation-systems.net/dusrm/app1/ssm-a-5.html

http://en.wikipedia.org/wiki/SSM-A-5_Boojum

http://www.secretprojects.co.uk/forum/index.php/topic,11635.msg111121.html#msg111121

An interesting book called The Evolution of the Cruise Missile, by Kenneth P. Werrell, Air University Press, Maxwell AFB, 1985, can be found in pdf. format here:

http://aupress.au.af.mil/digital/pdf/book/werrell_cruise.pdf

Photo Captions

1.      img779 – This scan of the N-25 3-view drawing comes from the in-house publication Northrop: An Aeronautical History, by Fred Anderson, Northrop Corp., 1976, (the “Brown Book”) and shows the early Snark configuration.  Note the flush inlet and high-mounted wings.  Tony Chong collection.
2.     xssm-a-5 – A drawing of the early Boojum configuration shows the similarities with the early Snark.  The main external differences are with the mid-mounted wings and annular inlet.  Image credit USAF
3.     100_0007_3 – Northrop issued a brochure in 1950 in an attempt to highlight the advantages of the Boojum to the customer.  This is a photo of the very dynamic cover art.  The artist is unknown, but it is very reminiscent of Jack Leynnwood, who occasionally worked for Northrop, but who also worked for the Revell and Aurora model kit companies, where he did a lot of their boxtop artwork.  Photo credit: Tony Chong
4. img736 – The brochure contained this baseline 3-view drawing of the Boojum.  As noted in the text, the vehicle was over 85 feet long; a very impressive size even today.  While the engines are far apart, Northrop projected minimal control disruption with asymmetric thrust and was supposed to retain enough engine-out performance on take-off to direct the vehicle to a safe ditching point away from the base or populated areas.  Tony Chong collection.
5.     img735 – This scan from the brochure shows the 3-view drawing of the Boojum and its large expendable fuel tank.  The tank slips over the bottom fuselage of the missile and extends beyond the nose and tail, increasing the length nearly 20 feet.  The sidebar art shows the tank being dropped in flight.  Tony Chong collection.
6.    img734 – Another artist’s concept shows a larger image of the Boojum, two with tanks and one in the midst of dropping a tank.  In real life separation would have been an interesting issue at Mach 2 for an unmanned vehicle carrying a conformal tank longer than itself.  Tony Chong collection.
7.   img771 – This plan-view drawing shows the Boojum with it straight-wing first stage.  Like the basic missile, the two-stage configuration was rail-launched.  Note the size of the wing and the tip tanks.  The sidebar shows the first stage dropping away from the missile.  Tony Chong collection.
8.    img772 – The profile and front view of the two-stage configuration shows the massive size of the pylon attaching the vehicles together.  The acceleration stresses during rail launch are interesting to consider.  All of the thrust appears to come from the Boojum’s two J47 engines.  No mention is made anywhere in the brochure of expendable rocket or jet assisted devices.  Tony Chong collection.
9. img773 – Another, larger artist’s concept showing a couple of Boojums in operation, one with its first stage attached and the other dropping its stage.  The art shows the drop taking place over land, which seems rather unlikely in real life.  In all probability Boojum basing would be near coastal areas and the drop points would be over water.  Tony Chong collection.
10.   img777 – This image shows some of the interior structure of the first stage.  The inset art appears to highlight one of the pylon attach points.  What looks like wiring could be part of an explosive bolt triggering mechanism for first stage separation.  Unfortunately the various launch configuration drawings appear to be from a second brochure, not all of which was copied, so details are elusive.  Tony Chong collection.
11. img778 – Ironically, one of the launch aircraft considered for the Boojum was the Convair B-36 Peacemaker.  This is a later version of the B-36 as it has the twin-engine jet pods outboard of the buried main piston engines.  The jets are non-afterburning General Electric J47-GE-19s, from the same family as the Boojum’s engines.  Tony Chong collection.
12.       img776 – The final image is intriguing not just for the Boojum on the back of the mothership, but for the mothership itself.  It is a swept-wing, swept-tail, four engine turboprop version of the B-36 with counter-rotating blades.  This is likely an early concept for what eventually became the jet-powered, eight-engine YB-60.  Note the mushroom cloud in the background.  Since the aircraft are over land, and the two are still together, one can assume a strike has been made against the American homeland and a retaliatory launch is moments away.  Tony Chong collection

2012 Garden Party Art Show

It's that time of year again for our annual Garden Party Art Show. If you are in the area, please drop by for some good art, good food and good conversation! Hope to see you then.

Northrop's TAB for All Seasons

It's been a long time since I've posted regularly. The answer is partially revealed here tonight.

For the last few years I've been writing articles for a variety of in-house magazines attached to the Northrop Grumman Engineering Department.  Starting sporadically with "The Leading Edge," a traditional hard-copy magazine, to "VelocitE," a combination pdf/on-line journal, to the current "Airspace" and its pure, on-line format, I've been gradually writing more and more current and historically-themed pieces.

Earlier this year I was given my own column. While exciting, it's been very time consuming as there is a lot of research involved in some of the articles. Also I've now gone on a 9/80 schedule at work, making for longer days and tougher commutes. Since I do all of my writing on my own time at home, something had to give. Sadly, that included blogging (I think eBay stock dropped as a result, too).

While I've gotten a lot of good response to my articles, I couldn't share them with anyone outside of the company. Fortunately, Diane Hensley, my very generous editor, granted me permission to reprint these on my blog. 

However, before I could do so, I had to get them cleared for public release through the Northrop Grumman system. That has been an interesting experience and something of an eye-opener. In today's environment, everyone is being extra cautious. It's understandable, but very frustrating at times.

I now have several articles that have cleared the process - photos included - with several more in the queue. I hope now that I will be able to post more regularly and you can see the results of my work. I hope you enjoy them.

This article was published in Airspace vol. 2 no. 7, May 2011. It is reprinted here with permission and has approved for release case number 12-1465.

Northrop’s TAB for All Seasons

By Tony Chong

Perhaps one of the most unusual designs proposed by the heritage Northrop Corporation was the Truck, Airplane, Boat (TAB) Vericraft triphibian, an ungainly looking vehicle that attempted to be the all-in-one answer to the U.S. Army’s looming tactical needs.

TAB was developed in the mid-1960s in an attempt to secure participation in an Advanced Research Projects Agency (ARPA) program called Project AGILE.  One of the issues under investigation was the problem of mobility and logistical supply to remote bases and outposts in inaccessible environments.  With the U.S. increasingly involved in the Vietnam conflict this was a major concern for military planners.

Northrop envisioned a rugged, easy to build, low-cost aircraft that had the ability to operate effectively not just in the air, but on the water and on land as well.  While primarily designed for the short-range utility cargo mission, it was to be easily adaptable for use as a troop transport, weapons carrier, mobile command post or medical evacuation vehicle.

The proposed craft featured a rectangular box of a fuselage outfitted with a catamaran hull, retractable wheels and rotatable wings and tail.  Twin Pratt & Whitney PT6-B15 turboprop engines, mounted in a single pod nacelle, provided power to a 7.5 foot shrouded propeller.  Engineered with a constant-chord wing with a span of 60 feet, the TAB was to be 40 feet long, with a folded wing width of 9.5 feet and a height of 13.5 feet.  The cargo compartment was to be 6 feet high, 6 feet wide and 15 feet long.  Gross weight, complete with up to 4,000 lbs of cargo, was projected at 12,000 lbs.

Conversion to any operational mode was anticipated to take approximately 10 minutes.  Additionally, all mode conversions could be done onboard the TAB during water operations.  The vehicle was also scaled to fit into the cargo hold of a Lockheed C-130 Hercules transport for long, overseas deployments.

Northrop expended considerable time and effort in this design.  A multi-volume proposal brochure was developed that included cost and operations comparisons to other proposed Army vehicles, including the fixed-wing de Havilland of Canada CV-2 (later C-7) Caribou and the rotary-wing Boeing-Vertol CH-47 Chinook and Bell UH-1 Iroquois (Huey).

Performance was projected to be modest.  The 130 mph air speed would be slightly faster than the Huey but much slower than the Caribou or Chinook.  Truck speed would top out at 50 mph.  Ironically the boat mode would provide the best performance with calm water speeds up to 35 kts.

A detailed scale model was built toward this effort, along with a larger scale radio controlled model of the basic TAB design.  Interestingly enough, no formal N-number was attached to the program.  While a Preliminary Design (PD) number was likely given to the TAB, its identity has proved elusive thus far.

In any event, the program did not go forward.  ARPA declined to offer funding, perhaps in part because the newly implemented 1966 agreement between the Army and U.S. Air Force mandated that the Army give up all fixed-wing tactical airlift capabilities in exchange for unrestricted development and acquisition of rotary-wing assets.  TAB’s primary customer was now obliged to go with the UH-1 and CH-47.  The end result was the coming of age of the helicopter-borne air-mobile Army during combat operations in the Vietnam War.

Kristi Harding contributed to this article.

For further reading on Project AGILE, go to: http://en.wikipedia.org/wiki/Project_AGILE

A look into the scope of Project AGILE can be found in this July to December 1963 semiannual report by ARPA, including Subproject III to which TAB was tailored: http://www.nal.usda.gov/speccoll/findaids/agentorange/text/00340.pdf

A review of the Army/Air Force 1966 agreement can be found here: http://en.wikipedia.org/wiki/Johnson-McConnell_agreement_of_1966

Photo Captions

1.                                                       100_0001_rlw: The TAB proposal brochure included this artist’s conception of the vehicle in a scenario that showcased all three modes.  Boat operations could take place on rivers, estuaries, coastal areas, lakes and, revealingly, rice paddies.  Clearly Southeast Asian environments were in mind.   Image credit: Tony Chong collection
2.                                     img662:  This 3-view shows the basic dimensions of the vehicle.  Note the split inlet on the nacelle for the twin P&W PT6-B15 turboprop engines.  As a point of reference, Northrop Grumman’s new X-47B UCAS-D is a couple of feet greater in span and about a foot shorter in length than the proposed TAB.  Image credit: Tony Chong collection
3.                                                     img665w:  All three modes of transportation are shown in this image.  The stowed wings would have shielded the shrouded prop, possibly dampening the noise for bystanders.  Image credit: Tony Chong collection
4.                                              img666w:  The wing and tail folding operations appear to be simple and straightforward, a plus for use by draftees in rough conditions.  Image credit: Tony Chong collection
5.                                                   img675w:  This detailed view, with cross-sections, shows the catamaran hull design of the TAB.  Image credit: Tony Chong collection
6.                                                      img676w:  The cockpit would have been a fairly basic affair.  Instrumentation was only installed on the “driver’s” side even though a second wheel was provided for the right seat.  Image credit: Tony Chong collection
7.                                  img667w:  TAB was designed to fit inside the Lockheed C-130 Hercules, albeit rather snuggly.  Note the Hercules outline is of the early C-130A “Roman-nose” configuration.  Image credit: Tony Chong collection
8.                                                   img670w:  The projected aircraft performance specs were very modest compared to other fixed wing aircraft, and even to some helicopters.  Obviously the selling point was the versatility of the land and water options.  Image credit: Tony Chong collection
9.                                                         img673w:  Projected truck performance was better, despite a top speed of only 50 mph and the ungainly addition of large exposed surfaces from the stowed wings.  One wonders how vehicle mobility would have been affected by this, much less their susceptibility to road damage and small arms fire.  Image credit: Tony Chong
10.                                   img671w:  Water performance would be rather good, all things considered, especially in speed.  Note the sea state operations/survivability figures.  Image credit: Tony Chong collection
11.                          Northrop TAB bw:  Old Polaroid photos found in the Display Model Shop archives show a rather nicely detailed scale model of the TAB in profile with cargo ramp down.  The angle of the nacelle and shroud is more pronounced in the model than in the 3-view, suggesting a different design iteration.  Photo credit: Northrop Grumman Display Model Shop
12.                           Northrop TAB cw:  Another Polaroid showing a high-angle view of TAB.  The size of the model is apparent when seen with the tabletop.  Photo credit: Northrop Grumman Display Model Shop
13.                                       TAB model lf frt:  This appears to be a studio shot of the TAB model with the wings and tail folded into the stowed position.  The shrouded propeller is effectively shielded by the wings.  They also appear to channel airflow to the prop.  Ground and water operations would seem to be similar to Airboat vehicles.  Since TAB was supposed to be able to handle 45% longitudinal slopes on a hard surface, propulsion via prop would’ve been interesting to see in those conditions.  Photo credit: Tony Chong collection
14.                                  TAB model lf rr:  The TAB cargo bay was designed to hold either a standard Jeep, Army Mule, M-102 105mm Howitzer or other like equipment.  The model shows two such payload options.  Photo credit: Tony Chong collection
15.                                Northrop RC cw:  Northrop authorized a Radio Control (RC) model for concept testing.  This is a shot of a straight-tail version under construction.  Note the catamaran hull and wood body.  Photo credit: Northrop Grumman Display Model Shop
16.                             14060-104Aw:  It is unclear if only one RC model was made or if there were more than one.  This image shows a variant with a pronounced dihedral to the tail.  There are endplates to the tail as well and a tricycle-type landing gear arrangement.  The propeller shroud also appears different in configuration, although that may be an illusion due to the large side support structure of the model.  Note the size compared to the cameraman.  Photo credit: Northrop Grumman
17.                              14063-104Bw:  This photo shows the model taking off for a flight.  It is unknown how many flight were made, or where.  It does not appear to be Hawthorne.  One thought is that it might be the old Rancho Conejo Airport, where the former Northrop Ventura Division facility was located near the southern end of the runway in Newbury Park, CA.  Photo credit: Northrop Grumman

Neil Armstrong

Neil Armstrong died today.

For those of us who vividly remember watching the ghostly t.v. images of him and Buzz Aldrin kangaroo-hopping on the Moon, this moment is a staggering and sobering reminder of the inexorable passage of time. An icon of an era is gone and our age and mortality are brought to the forefront of our consciousness like the blinking, blinding neons of Las Vegas. We are old, too, and feeling older by the moment.

But what a life he led, and what an amazing accomplishment! Yet he fully realized that what he did was on the shoulders of thousand and thousands of people working diligently and over long hours to make that mission a success. We like our heroes; we like them even better when they are modest and appreciative.

I had the chance to see and hear Neil Armstrong give a talk at the Society of Experimental Test Pilots convention a few years ago. The talk was on the flight tests and performance characteristics of the Lunar Landing Research Vehicle, the spindly bedpost of a machine that nearly killed him on one flight. It was a spellbinding talk. I'm glad I got to see it and him.

The Lunar Module, like the one that I shot above during our visit to the Kennedy Space Center in 2002, is a stark reminder of the audacity of that program. To think that Americans went to the Moon in that ungainly and fragile-looking vehicle is awe-inspiring. That it worked six times and saved the crew on the one other attempt is even more stunning. I hope America will be that audacious again.

Neil Armstrong will forever be the first human to walk on the Moon. As Charles Bolden, head of NASA said, as long as history books are written, he will be remembered. And he should be.

Godspeed, Neil Armstrong.  Well Done.

*Whew*  Life has sure been busy lately.  As you can see, Tina and I are going to be showing our art at the Sierra Madre Art Fair on May 5-6 at Memorial Park, 222 W. Sierra Madre Blvd., Sierra Madre, CA.  Come by and see us at booth 50!


I'll try to post a real blog soon!

Dart Two Dart

I've always liked the Convair F-106 Delta Dart. It is one of the sleekest, prettiest designs every made and a classic 1950s speed demon. While the single-seat interceptor is more angular and muscular, I must admit the two-seat trainer adds a pleasing curve to the Dart form.

I was happy to see the F-106B parked outside when we went to a model kit show this past January at the Yanks Air Museum at Chino Airport. Last year when we were there the Dart was crammed in amongst the other airplanes and a clean, overall shot was nigh-well impossible. While not the best angle, I was able to capture the whole bird on an overcast morning during our visit.

This particular aircraft was one of the Rockwell B-1 chase aircraft during the Lancer's flight test operations at Edwards AFB. It is definitely one very colorful marking for a very beautiful bird, and it was great fun to shoot it, even in marginal weather.

As I have mentioned before, the thing about "bad" weather is that you can still get some great images. Nature and landscape photographers know that well, but aviation shooters, especially the dedicated documentary slide traders, insist on sun-at-your-back, clear foreground and background, side-view or quarter-view, no mid-day or golden-hour images as capturing accurate colors and marking information is paramount.

But setting aside documentary parameters, great aircraft shooting can be had, particularly on tight images or unusual angles. I especially like the above shot with the light reflecting off the large canopy and fuselage. It's very dramatic and atmospheric. While it doesn't capture information, it does capture mood.

This last image is also one I really like. Since I knew we would be in the midst of a model show and sale, and since I didn't think anything would be outside, I left my tripod in the car. Fortunately the range on the Eos 40D allowed me to hand-hold all the shots that day with surprisingly good results. The head-on view was one of those happy moments. Again, poor on information, but a very dramatic and pleasing result. It was a very good day!