View Single Post
  #21  
Old January 7th 04, 10:07 AM
Scott Ferrin
external usenet poster
 
Posts: n/a
Default

On Wed, 7 Jan 2004 04:17:23 -0500, "John Keeney"
wrote:


"Scott Ferrin" wrote in message
.. .
Anyway of those seven designs they chose 1 and 2 to build prototypes,
which would become the YF-22 and YF-23. The design *as presented* by
Lockheed at that time was the one that couldn't fly. After they
teamed with General Dynamics GD told them essentially "look, your
design won't even be able to fly". Needless to say THAT went over
real well with Lockheed but GD was right. If you look and the
original LM & GD designs and compare them with the YF-22, the YF-22
resembles the GD proposal almost as much as it does LM's. The
production F-22 is even more so.


Can you point me to sketches of the Lockheed proposal?
And what was General Dynamic's objection to its air-
worthiness?



Right here

http://www.codeonemagazine.com/archi...8/apra_98.html

Go down to the "Lockheed Design"

Then go down to the GD design. If you ignore the vertical tail, the
GD proposal and the final F/A-22 are remarkably similar.

GD's reasoning on the original Lockheed design was that it had so much
area on the LERXs that in order for it to be anywhere near stable it
would have to have an impractically large horizontal stab.




http://www.codeonemagazine.com/archi.../oct2a_98.html




"The transformation of 090P into Configuration 1132, what is better
known as the F-22 prototype or YF-22, involved some of the most
concentrated work in the history of aircraft design. The
transformation got off to a strained start as the team members sized
up their relative strengths and weaknesses and argued for and against
a variety of design features. "The period was intense," says Paul
Martin, Lockheed’s deputy chief engineer for technology and design
during the period. "We spent a lot of time convincing each other what
great he-men engineers we all were."

The posturing was fed by the sheer amount of material available to
scrutinize as all three companies placed their work on the table.
Every one of the designs proposed by the three teaming companies had
its share of problems and advantages. As the official starting point,
however, Lockheed’s design was open to the most scrutiny and
criticism.

"After studying the design of Configuration 090P," recalls Murff, "we
soon realized that the airplane would not fly. Its huge forward glove
made the design uncontrollable in the pitch axis. The internal
arrangement would not go together. The large rotary weapon bay pushed
engines and inlets outward, which produced an excessive amount of wave
drag. And the rear-retracting landing gear design was not suited for a
fighter."



"After the General Dynamics team had been out in Burbank for about two
weeks, they sent home a set of drawings of the winning design,"
remembers Kevin Renshaw, the configuration design lead for General
Dynamics. "The first task for the engineers in Fort Worth was to put
the aircraft drawings into the computer to provide a base for
analysis. The immature status of the Lockheed design became
immediately apparent. The plan view, profile view, and sections on the
drawings had only a rough relationship to each other. After analyzing
the design, it became obvious that the aerodynamic and weights data in
the proposal had been ‘goal’ levels with little actual relationship to
the drawings. The design turned out to be a series of unconnected
sections drawn around individual portions of the aircraft’s
subsystems. Lockheed had a concept for an aircraft, not a point
design. However, that approach won the competition.""