VSX -- If Grumman did it Right

[KJ_Lesnick]

What are the advantages of the type of tailplane the S-2 uses, versus a more conventional single-tail? 


KJ

[Lawman]

Sorry guys, it wasn't some carefully thought design detail by me, I just forgot to move the wheels on the graphic! 

[KJ_Lesnick]

Sorry guys, it wasn't some carefully thought design detail by me, I just forgot to move the wheels on the graphic! 

No biggie. 


KJ

[elmayerle]

interesting lawman, the the main u/c would really have to go in the fuselage don't you think.

More likely it needs the engine nacelles carefully designed so that the gear can retract into the underside, most likely with a 90 degree rotation of the wheels (see, for ex. the P-40 and F4U main gear) to lie flat in the gear well.

Boeing would have liked that, another set of licensing fees. 

I'm not so sure they'd have gotten any, that's close enough to prior state of the art in main landing gear design (even the F-14's rotates to lay flat) that I don't think they could claim much, if anything.

[jcf]

interesting lawman, the the main u/c would really have to go in the fuselage don't you think.

More likely it needs the engine nacelles carefully designed so that the gear can retract into the underside, most likely with a 90 degree rotation of the wheels (see, for ex. the P-40 and F4U main gear) to lie flat in the gear well.

Boeing would have liked that, another set of licensing fees. 

I'm not so sure they'd have gotten any, that's close enough to prior state of the art in main landing gear design (even the F-14's rotates to lay flat) that I don't think they could claim much, if anything.

The landing gear used on the P-40 was designed to a Boeing patent (filed in 1933, granted in 1936) and originally licensed to Curtiss in 1934.
Boeing themselves did not use the design until the XF8B.
http://www.google.com/patents?id=pppPAAAAEBAJ&printsec=abstract&zoom=4&dq=boeing+landing+gear#PPA1,M1
Jon

[KJ_Lesnick]

JCF,

But I thought patents expire after a certain amount of time?  If it was designed in the 1930's by the late 1960's or early 1970's it should have been long-expired.


KJ Lesnick

[Metatron]

So it was kind of an excessive work-load kind of thing?  They weren't capable of cooking up a reasonable design?

There's also a little something called "industrial statesmenship" where the Navy will not award back to back large contracts to the same contractor.  So a contractor who just won a large bid will not put too much effort into the process if they don't think they have a good chance of winning.

[KJ_Lesnick]

So Grumman had no chance of winning anyway?  I thought Grumman assumed they were going to win and as a result simply went with a simple design as such?

KJ

[jcf]

JCF,

But I thought patents expire after a certain amount of time?  If it was designed in the 1930's by the late 1960's or early 1970's it should have been long-expired.


KJ Lesnick

Yes Kendra,
patents expire, my original post 'twas by way of being a joke.

Jon

[Jschmus]

Not to blow my own horn or anything, but I think I may have inadvertently kicked this thread off by some messages that KJ Lesnick and I exchanged vis-a-vis the F-14.  I've always been a fan of the big 'Cats, and when the Carolinas Aviation Museum acquired a de-milled "D" a couple of years ago, it kicked my interest into overdrive.  I bought a lot of magazines a couple of years ago, when the F-14 was retired.  I picked up every issue of Flight Journal, Air and Space, Combat Aircraft and a few other publications that had the least little blurbs about F-14s.  I even bought some way-back issues of Air Progress.  I remembered reading somewhere about how fouling the VSX proposal had jeopardized Grumman's chances with the F-14, but I couldn't remember a definitive, quotable source.  The June 2008 issue of Flight Journal contains such a source.

The article is entitled "Grumman's Guardian", by Corwin H. Meyer.  "Corky" Meyer was a Grumman test pilot from the 40s to the 70s, and later went on to work the business end of the company.  I've been reading his stuff for a few years, and he knows what he's talking about.  The article details the development of the AF Guardian, Grumman's first purpose-built ASW aircraft.  He traces the program from its origins in modified TBF Avengers, to the aircraft's eventual replacement by the S2F Tracker.  An epilogue to the story talks a little about the VSX proposal.

"Arrogance ends the Grumman ASW monopoly
After building 11,489 Anti-Submarine Warfare Avengers, Guardians and its follow-on S2F twin-engine Trackers, Grumman lost the next ASW carrier aircraft competition on August 1, 1969, to the Lockheed S-3A Viking.  Although I was no longer director of business development, I was sent by the Grumman president to Washington to find out why.  A former Navy friend allowed me to read the decision paperwork.  It stated, "The Navy expected Grumman to win after their continuous 28 years of supplying the Navy with excellent ASW aircraft.
Because of Grumman's pompous attitude expressed in their very skimpy proposal, they were rated 25th in a five-company competition!"  I went home and read our proposal.  It was a "Send us the money and we will make you the next ASW aircraft" - a real ego-trip dud by Grumman.  This team from engineering was never allowed to do a preliminary design again."

[KJ_Lesnick]

Okay, so it was arrogance that ended up costing Grumman the contract...

So, how *should* Grumman have gone about it?

[Hobbes]

What are the advantages of the type of tailplane the S-2 uses, versus a more conventional single-tail? 

You mean as shown here?:


the basic S-2 had a conventional tailplane.

Twin vertical tailplanes can be lower than a single item, so it's easier to conform to height constraints (hangar height) than with a single tail.
The drawback is that the construction of the horizontal tailplanes must be stronger and heavier, and you may end up with more surface area and weight for the vertical tailplanes as well (two smaller surfaces are less efficient than one large tailplane).

They do offer more control authority (more torque for a given deflection).

[KJ_Lesnick]

Okay, let's get down to business with a good idea.  What should their design have been like? 

I'm guessing, more like the S-3 Viking?


Kendra Lesnick
BTW:  To Jschmus, did the S-3, and the other competitors all use the same electronics equipment (or at least equipment with similar capabilities), assuming it's not classified or something?

[dy031101]

It was a "Send us the money and we will make you the next ASW aircraft" - a real ego-trip dud by Grumman.

That was such a bad sales pitch...... now I have a better understanding of the topic.....

[KJ_Lesnick]

That was such a bad sales pitch...... now I have a better understanding of the topic.....

Yeah, that was the most arrogant, cocky advertisement pitch I've ever heard... 

KJ