Wednesday, October 31, 2012

The Might-Have-Been Mercury - The Grumman G-214

Researching little-known heritage Grumman projects and proposals for articles is always a challenge for me as most of the really good primary source materials are on the East Coast. Since I rarely travel back there, finding other ways to access that data becomes important. The Internet and local libraries are great, but they have their limitations in what they offer.

Fortunately for historians there is the Northrop Grumman History Center in Bethpage, NY. While I prefer to poke around archives myself looking for interesting material when I can, in this case I relied on the good graces of the staff at the History Center to fulfill my request. Run by Grumman retiree Larry Feliu, he and his crew did a great job in finding and copying many of these images for me. 

I will definitely have to visit there some day.

This article was originally published in the Northrop Grumman Engineering Department in-house, on-line magazine Airspace, Vol. 2, No. 11, August 2010. It is re-posted here with permission and has approved for public release case number 12-1475.


The Might-Have-Been Mercury –
The Grumman G-214

By Tony Chong

Grumman’s bid for the Manned Space Capsule competition, also known as Project Mercury, was not a total surprise despite the company’s lack of participation in previous space vehicle studies and proposals.  Indeed, every major aircraft company not already participating in the X-20 Dynasoar program eagerly sought a piece of the new civilian space pie.  What was surprising was the fact that they nearly won.

But while Grumman’s entry into the competition was new, their bid was not a spur-of-the-moment effort, but a calculated and evolutionary step in the company’s long-range plans.

The initial stepping stones were their work on advanced avionics and on the Rigel and Eagle missile programs.  After Sputnik, Grumman formed the Long Island Space Team with rivals Republic and Fairchild.  While nothing much emerged from this team, it did let NASA know Grumman was interested in becoming a serious contender on future space programs.

Internally Grumman created the Space Steering Group in 1958 headed by a preliminary design engineer named Al Munier.  It was this group that created the in-house designated G-214, Grumman’s bid for the Mercury Capsule.

Unfortunately, the proposal and related data on the G-214 are very hard to find now, over fifty years after the program submission.  The only information retrieved thus far comes from Larry Feliu of the Northrop Grumman History Center in Bethpage, Long Island, New York. 

What is available is tantalizing.  Like the Northrop N-227 (see previous entry) and the winning McDonnell Mercury proposal, the Grumman G-214 is based on the blunt-body ballistic capsule with high aerodynamic drag. 

No dimensions were available as of this writing, but the accompanying scanned images provide some hints.  The drawing shows what appears to be the North American Aviation “Little Joe” rocket built specifically as a low-cost, sub-orbital booster to prove out the Mercury capsule hardware and its proposed launch-abort sequence.

The Little Joe had a diameter of 80 inches.  The N-227’s diameter was also 80 inches.  The McDonnell capsule was only 74.5 inches.  In photos the taper on the adapter ring between the McDonnell capsule and Little Joe body appears slightly greater than the taper on the G-214 drawing.  The obvious inference is that the G-214 had a diameter between the two, probably somewhere around 77 or 78 inches.

More intriguing are the deployable panels on the forebody of the Grumman design.  Appearing somewhat like the tail retarding device used on the Mk. 82/Snakeye bomb, which slowed the ordnance down rapidly when dropped at low altitude so the carrier aircraft could clear the blast pattern, this feature perhaps performed a similar function in concert with the already high-drag blunt-body shape of the capsule.  Or perhaps, if the panels could open separately, it could provide differential drag to give the capsule a limited cross-range capability, something lacking on the purely ballistic Northrop and McDonnell vehicles.

Then again, given the weight penalty of such a device on the real spacecraft, perhaps they were attached only to the model to emulate the drag effects of the parachute system in the tunnel.  Without the actual technical data to tell, the true nature of the angled panels is difficult to ascertain.

In any event, the Grumman proposal scored exceptionally well in the technical and management categories.  Indeed, the NASA selection board felt there were only two highly qualified competitors: Grumman and McDonnell.  But there were other factors to consider beyond that, and they proved fatal to the G-214.  On January 12, 1959, McDonnell was awarded the Mercury Capsule contract.

As the first NASA Administrator, T. Keith Glennan, later explained to Congress:

“The reason for choosing McDonnell over Grumman was the fact that Grumman was heavily loaded with Navy projects in the conceptual stage.  It did not appear wise to select Grumman in view of its relatively tight manpower situation at the time, particularly since that situation might be reflected in a slow start on the capsule project regardless of priority.  Moreover, serious disruption in scheduling Navy work might occur if the higher priority capsule project were awarded to Grumman.”(1)

In short, Grumman’s own A2F Intruder (later A-6) and W2F Hawkeye (E-2) programs scuttled their bid.  Yet, all was not lost.  Grumman had proven to NASA it was a formidable player in the space game and NASA had taken notice.  Less than three years later, after the A-6 and E-2 programs were on track to the Navy’s satisfaction, NASA awarded perhaps the greatest prize of all to Grumman: the Lunar Module, the vehicle that would take men to and from the surface of the Moon.

(1):  Swenson, Grimwood and Alexander, “This New Ocean – A History of Project Mercury,” NASA SP-4201 in the NASA Historical Series, U.S. Government Printing Office, 1966, page 137.

Larry Feliu of the Northrop Grumman History Center contributed to this article.

Any further information on the Grumman Mercury proposal would be greatly appreciated by the author for incorporation in a possible future follow-on article.

For further reading, check out:

“This New Ocean – A History of Project Mercury” by Swenson, Grimwood and Alexander, NASA SP-4201 in the NASA Historical Series, U.S. Government Printing Office, 1966.

“The Grumman Story” by Richard Thruelsen, Praeger Publishers, Inc., New York, New York, 1976.

Photo Captions

1.                                                                         This isometric exploded drawing of the Little Joe and G-214 shows a Grumman boiler-plate capsule with adapter ring.  The slight taper indicates the diameter is smaller than the 80 inch barrel of the Little Joe body.  Credit: Northrop Grumman History Center.

2.                                                           The last in the series of Little Joe tests was LJ-5, which used a real McDonnell Mercury capsule rather than the McDonnell boiler-plate test articles.  Note the difference in adapter ring taper from the G-214 drawing.  The adapter ring is the burnished metal section below the dark band of the capsule and just above the “U” in United States.  Ironically, the LJ-5 launch on November 8, 1960 was a failure and resulted in the destruction of the capsule.  Photo credit: NASA

3.                                                        Grumman built a full-scale mock-up of the G-214.  Like all the other Mercury contenders the capsule was a small vehicle.  The circular hatch and figure give scale to the size of the G-214.  Credit: Northrop Grumman History Center.

4.                                                                          The mock-up had a cut-away section to reveal the inside of the vehicle.  The figure in the seat/couch and the size of the instrument panel shows the tight quarters inherent in the G-214, and indeed all the capsule designs.  Credit: Northrop Grumman History Center.

5.                                             A shot of a wind tunnel model of the G-214 with the NASA-prescribed launch-escape rocket tower structure.  Like the Northrop N-227, the structure attached to the nose of the capsule.  Credit: Northrop Grumman History Center.

6.                                               Another view of the tunnel model with the launch-escape rocket tower structure removed from the nose of the capsule.  Credit: Northrop Grumman History Center.

7.                                         The combined G-214 capsule and launch-escape rocket tower structure are shown on a sting in the wind tunnel either before or after a test.  The capsule appears to be made of laminated wood.  Note the paneled segments on the forebody with insert holes.  Credit: Northrop Grumman History Center.

8.                                              Another shot of the capsule in the tunnel, but without the launch-escape rocket tower structure.  The purpose of the flanges around the base of the capsule is unknown.  The insert holes on the forebody are more clearly shown here.  Credit: Northrop Grumman History Center.

9.                                          Angled panels are attached to the holes in the forebody of the G-214 tunnel model in this photo.  It is unclear whether these panels were to mimic actual parts on the real spacecraft or were test features only.  Credit: Northrop Grumman History Center.

10.                                           A view of the attachments from the blunt end of the capsule shows the extent of the deflection from the forebody.  The white and dark patterns on the section between the bottom of the capsule and the panels are the reflections of the panels on the conical surface of the model, giving the illusion of a notched structural feature where none actually exists.  Credit: Northrop Grumman History Center.

11.                                          As a comparison, this shot of a Mk. 82/Snakeye model in the NASA Langley wind tunnel shows the aerodynamic braking panels on the bomb.  The difference is the panels open in the direction of travel on the Snakeye and opposite the direction of travel on the G-214.  If the angled panels were meant to represent real features on the spacecraft, the much higher speed of the capsule during reentry would likely rip the panels off if they were opened in the same direction as the Snakeye.  Credit: NASA.

12.                                                            The scanned cover page is of interest for two reasons: First it spells out the official titles and number designations for the three volume G-214 proposal along with the cross-referencing key words.  Secondly, the added notation contains the phrase “…Just won the A-6(.) Navy ‘we told NASA not to pick you.’”  Since “A-6” was used and not “A2F,” the note was added after the Defense Department’s 1962 mandated change in the military’s aircraft designation system and at least three years after the Mercury contract award.  Credit: Northrop Grumman History Center.

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